ML090340105

NPDES Permit No. TN0026450 - Application for Renewal, Cover Letter Through WR2009-1-45-151, Figure 11

ML090340105
Person / Time
Site:	Sequoyah
Issue date:	01/27/2009
From:	Cleary T Tennessee Valley Authority
To:	Urban R Office of Nuclear Reactor Regulation, State of TN, Dept of Environment & Conservation
References
TN0026450
Download: ML090340105 (296)

Text

{{#Wiki_filter:TVA SEQUOYAH NUCLEAR PLANT NPDES PERMIT RENEWAL APPLICATION JANUARY 27, 2009 NRC Copy

Tennessee Valley Authority, Post Office Box 2000, Soddy Daisy, Tennessee 37384-2000 January 27, 2009 State of Tennessee Department of Environment and Conservation Chattanooga Environmental Field Office Division of Water Pollution Control State Office Building, Suite 550 540 McCallie Avenue Chattanooga, Tennessee 37402-2013-Attention: Richard Urban, Ph.D., Environmental Field Office Manager

Dear Dr. Urban:

TENNESSEE VALLEY AUTHORITY (TVA) - SEQUOYAH NUCLEAR PLANT (SQN) - NPDES PERMIT NO.-TN0026450 - APPLICATION FOR RENEWAL Enclosed are two copies of the National Pollutant Discharge Elimination System (NPDES) renewal packet for SQN consisting of NPDES Permit Application Addresses Form, EPA Form 1 with an attachment for additional permits, site map, flow schematic, and EPA Form 2C (one form for each Outfall - 101, IMP 103, IMP 107, 110, 116, 117, and 118). For Ouffalls IMP 107, 110, 116, 117, and 118, Part V-A, B, and Care not included since the outfalls were not sampled. A note has been made on Part II of the 2C forms for all five outfalls indicating why the outfalls were not sampled. TVA would appreciate consideration of the following in the renewed permit. Outfall 101

1. Enclosed is a summary of the Reasonable Potential (RP) evaluation and toxicity test results since January 2003. As discussed in the enclosure, TVA requests the following changes:.

a. TVA requests that the current permit's requirement for the B/CTP to govern the frequency of biomonitoring remain (i.e., once per year when oxidizing biocides are used, and once per year when non-oxidizing biocides are used).

b. TVA requests that the current permit limit. be replacedwith an IC25 Monitoring Trigger = 42.7%/o, which is based on revised effluent flow, and is consistent with the TSD guidance for effluents demonstrating No Reasonable Potential.

Toxicity at the instream wastewater concentration (IWC) would serve only as a hard trigger for accelerated biomonitoring, and not as a permit violation as indicated in the current permit.

Dr. Urban Page 2 January 27, 2009

c. TVA requests that all permit language referencing the "Permit Limit" be changed to "Monitoring Limit", and all references to "a violation of this permit" be removed. Suggested language for exceedance of the monitoring limit might include:

          "Toxicity demonstrated by the tests specified herein shall serve as a trigger for accelerated biomonitoring." (page 20 of 25, paragraph4, sentence 2, currentpermit)
          "Effluent toxicity that is not consistent with the intake, toxicity conditions specified above shall serve as a trigger for accelerated biomonitoring." (page 20 of 25, paragraph4, sentence 5, current permit)
          "In addition, the failure of a follow-up test shall serve as a trigger for accelerated biomonitoring." (page 21 of 25, paragraph1, sentence 4, current permit)
          "Toxicity demonstrated in any of the effluent samples as specified above shall serve as a trigger for accelerated biomonitoring." (page R-23 of R-49, paragraph 1, sentence 2, current permit)

d. TVA requests changes from the current "Permit Limit" to the appropriate "Monitoring Limit" as follows:

Page 20 of 25, table following paragraph2: Serial Dilutions for Whole E.'fflu.ent:Toxicity (WET) Testing 100% + Monitoring Limit 0.5 X ML 0.25 X ML Control Effluent (100+ML)/2 (ML) I I

                                                %Yeffl~uent 100         71.4               42.7           I     21.4        10.7     0 Page 20 of 25, paragraph4, sentence 1:
          "Toxicity will be demonstrated if the IC25 is less than the monitoring limit indicated in the above table."

e. TVA also requests that the Wastewater Flow in the table found in Section XI of the permit rationale be changed to 1491 MGD, with the DF = 2.3 and the revised IC025_ 42.7.

f. TVA recommends that all other text in Section E of the permit and Section XI of the permit rationale remain unchanged.

Dr. Urban Page 3 January 27, 2009

2. TVA requests continuation of the 316(a) alternative thermal limit and water temperature monitoring requirements as incorporated in the current permit.

Based on the results summarized in the enclosed ?'Biological Monitoring of the Tennessee River Near Sequoyah Nuclear Plant Discharge 2004, 2005, 2006, 2007, and 2008" reports, TVA believes that thermal discharges from SON have not had a negative effect on the maintenance of a.balanced indigenous fish population in Chickamauga Reservoir. Also enclosed are additional reports for studies related to evaluation of Clean Water Act Section 316 as required by Part III, Section F of the current NPDES permit and the study to confirm the calibration of the numerical model as required by Part III, Section G. Outfall 103 (Internal Monitoring Point) TVA requests a reduction in the monitoring frequencyfor Oil and Grease (O&G) and Total Suspended Solids (TSS) from weekly to monthly. Of the over 700 analyses performed since October 1996, Oil and Grease concentrations have generally been below detectable limits.. The maximum concentration of any O&G sample for this period was 11 mg/L, which is still well below the daily maximum limit of 20 mg/L. In addition, multiple barriers are in place to prevent discharges of oil from IMP 103 into the Diffuser Pond (Outfall 101) such as best management practices and the operational characteristics of the turbine building sump. Over this same time period, the results for TSS have generally been less than 20 mg/L. The maximum concentration of any TSS sample for this period was 43 mg/L, which is still well below the daily maximum limit of 100 mg/L. Outfalls 116 and 117 TVA requests that the reporting requirement for observations of these discharges be deleted. Historically, there have been no problems with visible sheen or floating matter. Also, BMPs are in place to control trash and debris as required by the permit: Deletion of the reporting requirement would be consistent with the NPDES permits for TVA fossil plants located in Tennessee which have similar intake screen backwash systems. Miscellaneous

1. On the cover page of the current NPDES Permit the Tennessee River Miles were swapped for Outfall 116 and Outfall 117. Outfall 116 should be TRM 485.2 and Outfall 117 should be TRM 484.85.

2. SON requests to add pressure washing and vehicle rinsing to our Yard Drainage

• flow.

3. In a letter "Sequoyah Nuclear Plant (SON) Diesel Fuel Oil Interceptor System:

Trail Closure" dated February 28, 2006 addressed to Dr. Richard Urban, TVA SON requested approval of a proposal to initiate trial closure activities. TVA SON never received correspondence from TDEC on this issue and is now. requesting closure of this issue. Original letter is included with the application renewal.

Dr. Urban Page 4 January 27, 2009

• If you have any questions or need additional information, please contact Ann Hurt at (423) 843-6714 or Stephanie Howard at (423) 843-6700 of Sequoyah's Environmental staff.

Sincerely, Timothy P. C1ea Site Vice President Sequoyah Nuclear Plant Enclosures cc (Enclosures): U.S. Nuclear Regulatory Commission ATTN: Document'Control Desk Washington, D.C. 20555 9

DEPARTMENT OF ENVIRONMENT AND CONSERVATION NPDES PERMIT APPLICATION ADDRESSES All addresses must be completed even if the same address is used: NPDES PERMIT NUMBER: TN0026450 CORPORATE HEADQUARTERS (where permit should be sent): CONTACT PERSON: Stephanie Howard Environmental Engineer TELEPHONE: 423-843-6700 Name Title COMPANY NAME: Tennessee Valley Authority - Sequoyah Nuclear Plant STREET AND/OR P.O. BOX: SB 2A. Sequoyah Access Road, P.O. Box 2000 CITY: 'Soddy-Daisy STATE TN ZIP CODE: 37384 PERMIT BILLING ADDRESS (where invoices should be sent): CONTACT PERSON: Stephanie Howard Environmental Engineer TELEPHONE: 423-843-6700 Name Title FACILITY NAME: Tennessee Valley Authority - Sequoyah Nuclear Plant STREET AND/OR P.O. BOX: SB 2A, Sequoyah Access Road, P.O. Box 2000

• CITY: Soddy-Daisy STATE: TN ZIP CODE: 37384 FACILITY LOCATION (actual location of permit site):

CONTACT PERSON: .- Stephanie Howard Environmental Engineer Name Title FACILITY NAME: Tennessee Valley Authority - Sequoyah Nuclear Plant STREET AND/OR P.O. BOX: SB 2A. Sequoyah Access Road, P.O. Box 2000 CITY: Soddy-Daisy STATE: TN ZIP CODE. 37384 COUNTY: Hamilton County TELEPHONE: 423-843-6700 DMR MAILING ADDRESS (where preprinted Discharge Monitoring Reports should be sent): CONTACT PERSON: Stephanie Howard Environmental Engineer TELEPHONE: 423-843-6700 Name Title FACILITY NAME: Tennessee Valley Authority - Sequoyah Nuclear Plant STREET AND/OR P.O. BOX: SB 2A, Sequoyah Access Road, P.O. Box 2000 W CITY: Soddy-Daisy STATE: TN ZIP CODE: 37384 CN-1090 RDAs 2352 AND 2366

Please print or type in the unshaded areas only (fill-in areas are spaced for elite type, I.e., 12 characters/inch). Form Approved. OMB No. 2040-0086. Approval expires 5-31-92 FORM U.S ENVIRONMENTAL PROTECTION

o. r n AGENCYnO, EPA I.  :ý - 11 ý-

GE L EPCosldtdPrisPormFI "LITEMS If a preprinted label has been provided, affix in the designated space. Review the information care-fully; if any of it is incorrect, cross through it and enter the correct data in the appropriate fill-in aree below. Also, if any of the preprinted data is absent (the area to the left of the label space lists the intormation that should appear), please provide it

      .F    1L                                                                                                                               in the proper till-in area(s) below. It the label is
           ýL G D            E                                                                                                               complete and correct, you need not complete Items 1, i, V, and Vt (except VI-B which must be completed regardless). Complete all items it no label has been provided. Refer to the instructions for detailed item descriptions and for the legal authorizations under which this data is collected.

II. POLLUTANT CHARACTERISTICS UT I omplete t roug to etermine whether you nee tsbtapcaon tn y sorm's 7 must submit this form and the supplemental form listed in the parenthesis following the question. Mark "X" in the box in the third column if the supplemental form i! attached. If you answer "no" to each question, you need not submit any of these forms. You may answer "no" if your activity is excluded from permit requirements; se Section C of the instructions. See also, Section D of the instructions tor detinitions otbold-faced terms. MARK 'X' MARK 'X' SPECIFIC QUESTIONS YES NO FORM SPECIFIC QUESTIONS YES NO FORM ATTACHED ATTACHED B. uoes or will tnis tacility (either existing or proposed) A. Is this tacility a publicly owned treatment works X include a concentrated animal feeding operation or X which results in a discharge to waters of the U.S'? aquatic animal production facility which results in (FORM 2A) 16 17 18 a discharge to waters of the U.S.? (FORM 2B) 19 20 21 C. Is this a tacility which currently results indIschlarges O. is tins a proposed tacility (other than those descneed to waters of the U.S. other than those described in X in A or b above) which wilt result in a discharge to X A or B above? (FORM 2C) waters of the U.S.? (FORM 2D) . 22 23 24 25 26 27 F. Do you or will you inject at this facility industrial oi E. Does or will this facility treat, store, or dispose 1 . X municipal effluent below the lowermost stratum con- X hazardous wastes? (FORM 3) taining, within one quarter mile of the well bore, 28 29 30 underground sources of drinking water? (FORM 4' 31 32 33 U. L or will you finect at this facility any producei: ww r other fluids which are brought to the sur. H. Do you or will you inject at this facility fluids for specia face in connection with conventional oil or natural X processes such as mining of sulfur by the Frasch X gas production, inject fluids used for, enhanced process, solution mining of minerals, in situ combus-recovery of-oil or natural gas, or inject fluids lot tion of fossil fuel, or recovery of geothermal energy,

    -storage of liquid hydrocarbons? (FORM                                    36                            (FORM44)                                                                 3           38         39

1. IS this facility a proposed stationary source wnich is J_ is this facility a proposed stationarysource which is one of the 28 industrial categories listed in the in- NOT one of the 28 industrial categories listed in the structions and which will potentially emit 100 ton X instructions and which will potentially emit 250 tom X per year of any air pollutant regulated under thE per year of any air pollutant regulated under the Clear Clean Air Act and may affect or be located in an Air Act and may affect or be located in an attainment attainment area'? (FORM 5) 4 " 42 area'? (FORM 5) , 44 45 11.NAME OF FACILITY ý,A P - ~.I c' J

                                              . 01 M. k..11 U,      ui  T . mi Mi   i Ni Ui U      L    C. M. M.       . r- I L , M 1 114. 1 .       . II   .    .   . I      .    . I   I   I 151 16-29 130                                                                                                                                                                                               691 IV. FACILITY CONTACT B. PH N         area code &no.)

A EA JIEIat FTig&I i'e I III HO W A!R IDI !ST:EIPIHANII E: E N.V., ENGI N EE ,R_ 4 2: 3 8: 4 3] 16! 7 0, 1516 4546-48 49 -51 52- 55 V. FACILITY MAILING ADDRESS A. STREET OR3P.P 0BOX 3 SB 2!A, PR!.O. BO 1X. 2 10 10 10 1111111F 15116 _ 45 4 SO. D1 DY! D: DA:I:SIY [IN 3171384 16 16 VI. FACILITY LOCATION 15 16 45D. IS. CI~TY N9ATOp D.UT ZIý CODE F.~CO UNTIn)COD HI )161 1! LIT 01 N .,' ", I 1 I 1-I 1 1 1 C. .CITY OR TOWN 701 .STATE E. ZIP CODE F. )NY CODEJ 6 SOD D!Y -iDAI !S!Y! TN 137 138141 151 1ýI I I I I I I I I I I 140 41142 1 471 - 1 51 15 54 E:PA Form 3510-1 (8-90) CONTINUE ON PAGE 2

CONTINUED FROM PAGE 1 VII. SIC CODES (4-digit, in orderof priority) A. FIRST B.SECOND F"I I (specify c (specify) c Electric Services 7 isJ 1115 Ni 16 -1 C. THIRD D. FOURTH c I I I speciy) c specily) 7 7 15 16 19 N15 16 - 91 Vill. OPERATOR INFORMATION A. NAME - B. Is the name listed as

...-                          -I"I                        l I     II  I    I    I   I   I    I I I        I    I    I     I    I    I  1    1                               1   1    1   1  1         Item VIII-A also the T     E N               E S S E E                V A L L E Y                    A U T H O R                 I T Y                                                                               owner?

81 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 I1 1 1 1 EYES [-]NO 1,5] 16, 551 66 C. STATUS OF OPERATOR (Enter the appropriateletter into the answer box; if "Other",specify.) D: PHONE (area code & no. F = FEDERAL M = PUBLIC (otherthan federal or state)j (specify) LcJIII I II I I S = STATE 0 OTHER (specify) [81

                                                                                                                                                                        .F      1 241                     3        61 71010 P    = PRIVATE                                                                                           615.                                                            116    -81       119. 211    122     -   25 E. STREET OR P.O. BOX I    I     I    I      I     I 'I    I   I   I   I    I I I I I I I                 I    I   I    I   I    I    I     I    I    I  I P.O.,             BOX, 12,01010,                        1   1   1    1    1   1   1        1 26                                                                                                                                       55 F. CITY OR TOWN                                                           G. STATE           H. ZIPCODE                 .INDIANLAND I IFI              Is the facility located on Indian lands?

B S,O,D D,Y,-,D,AI,SyY T, N 3,7,3,8,4 DYES E]NO 15 16 40 41 42 47 51 52 X. EXISTING ENVIRONMENTAL PERMITS A. NPDES (Discharqesto Surface Water) D. PSD Air Emissions from ProposedSources) Cf T 1 I I I_ rIr _T I 7 T 1 4 I _T _Operating permit, Cooling Tower, Unit 1 91NI JT,N,0,0,2,6,4,50, . I41,50r3q60p7Q1-p1Q P ,I I 151 161471 18 30 15 16 17 18 .30 See Next page for other air permits B. UIC (UndergroundInjection of Fluids) E. OTHER cieci C _T I I I I II T C1_ I I EI O I _ s_ e l I ( sp e c ify ) 9 6U 913a ~1 IDM ~ L Is333 181 Ie 1710,50, 00 2, 1, SQNnertLandfillPermit 15161_17118 ý30 15116117118 .301 __________________________ C RCRA(Hazrdous Wases) E. OTHER s eci I _ rC I .I_ T. I I I _ . I (specity) 94 R T ,N, 5, 6, 4,0 0, 2, 01 51 0, 4, 91 ITN,RR, 0, 5, 0, 0, 1, 5. . . . General Storm Water Permit 15 16 17 18 30 15 1.-MAP Nun I-ýZ Attach to this application a topographic map of the area extending to at least one mile beyond property boundaries. The map must show the outline of th, facility, the location of each of its existing and proposed intake and discharge structures, each of its hazardous waste treatment, storage, or disposal facilities, and each well where it injects fluids underground. Include all springs, rivers and other surface water bodies in the map area. See instruction! for precise requirements. XII. NATURE OF BUSINESS (provide a brief description) Production of electric power by thermonuclear fission and other associated operations. XIII. CERTIFICATION (see instructions) ... I certify under penalty of law that I have personally examined and am familiar with the information submitted in this application and all attachments an( that, based on my inquiry of those persons immediately responsible for obtaining the information contained in the application, I believe that the information is true, accurate and complete. / am aware that there are significantpenalties for submitting false information, including the possibilityo1 fine and imprisonment. A. NAME & OF-ICIAL 1 ITLE (type or print) B. SIGNATURE C. DATE SIGNED Timothy P. Cleary Site Vice President, Sequoyah Nuclear Plant AM S IC COW rR 0--CA--7-OL77,7 C_, F, EPA F-orm .3510A (Ut-90)

Form 1 General Section X Existing Environmental Permits 0 Chattanooga-Hamilton County Air Pollution Control Bureau 4150-30600701-03C Operating Permit, Cooling Tower, Unit 2 4150-30700804-06C Operating Permit, Insulation Saw A and Saw B 4150-10200501-08C Operating Permit, Auxiliary Boilers A and B 4150-30703099-09C Operating Permit, Carpenter Shop 4150-30900203-1OC Operating Permit, Abrasive Blasting Operation 4150-20200102-11 C Operating Emergency Generators IA, IB, 2A, and 2B and Permit, .Blackout Generators I and 2

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                                                                                                                                                                                                                                'r"*        Ht                                    SystetLeans Raw Cooling andRaw Se-ce Wat(er 0.87491                                                      -                     .OeMode                                                40.41361"                        --         * *I                        Yardl Dra'inage I                        rdminoma..     .. lealk
                              "~~~0                                                                0 1                    III                                                          I         Y, a r --         I I   . . S .y    t e. . .                I e ss ure       ah im &V e hicle Rins ing*

Raw Service Water Syste A / o al -e ow o be u b a l at m n g e2.1u tN Pon Drainage ISRu14o0f1FLOW SCHEMATI J ) Pond System.NDPEfuser

                                            ~~Component                      I       *e          I*0541I.                                                              ,         4.        19*06                 Lo Voum                          No.

0,12 Ouaste0 P1490.79.2 R e n I fCooling System F i 2 gal/yr Flow Outfall 103is0wgal/yr eesenprcipiatio ' Repress eaastio I e WTreatment 0.1767 _ Pond I Miscellaneous I -q. 0.052 0002* ý:o= ... 0.0009" I I Equipment Cooling -- "-' ' -

• _* .. . .q *j 1 *1 I* c-."- = -

I

• I Il~ccs Waste Tu.rbine

                                                                                                                    *         .                      <T      <1          *    *      -oeo

_lTurbine Building Floor &l*.' 0.0011 0o.o00618 I W ater Treatm ent * ' I I -I L0.l, , 160oo0 Equip ment Or:0 Plant " 0096 * *

• Building Sum p .,o** 4 - 1/*

                                                          '1        *-'".i'   *Primry  ,°°°°                                    *.,,.

• Lin~ed Metal Unlline~d Metal I Steam I IJ \ yt mI- * **Liquid Radwaste L ,Cleaning , -*_ ,Cle~aning ,

IIGenerator I -I"Ic-[-* P~ond *'Waste Pond Fll 1o" - 02 1 , +. *iTreatment

                                                                                                                                                                                    ' . +,               System 17IWaste
                                                                                                                                                                                                                     '+;                                     ' '

• 1 I -- I"* R adioactive Floo~r
• IR esin/Fiter " 7o lSteamGeneratorBElowaovn Codnst 0.1ooo0 Condensate IDrains &Sumps Dis// posal ,

                  ]      ,JSecondary Systeml                Deielzr                                             eieaie                                                     i                                                                                            Metal Cleaninle
              .I *Iak
                                ,b *I Lea~s
                                              &II ol

• I I Syste m I I e en r t o Wa e ,,

RegenerationIW aste Radioactive l I IW est Valve Vault, l[ Laundry, Hot

. . . .Ig 0.000"* , AI:.

Laboratory IRI I loom Drains b ow er., & . W astv e Secondary [ ISystem Iposa

             ¥l      ll

[. DIra ln aow ns-

                                                                            -                                       +Waste                              water    IChemical                                                Sh Drains.

SEQUOYAH NUCLEAR PLANT All flows in MGD A - denotes alternate flow path to be used by authority of plant management NPDES FLOWi SCHEMTIC265

  -,. Represents intermittent flow

• Flow is 200 gallyr "*Flow is 0 gallyr 1121Prmt2o.TN0 26450 t;@ Represents precipitation Q Represents evaporation . Represents Storm Water1/720

SEQUOYAH NUCLEAR PLANT WATER TREATMENT PLANT Raw Service Water All flows in MGD

        *Flow is 200 gal/yr

EPA I.0. NUMBER (copyfrom Item I ofForm 1) Form Approved. OMB No. 2040-0086. Please print or type in the unshaded areas only. TNS 64 002 0504 Approval expires 3-31-98. 4 FORM NPIDES

                  *# C 480E
               'Consolidated PAEXISTING p

APPLICAT ON FOR PERMIT TO DISCHARGE WASTEWATER MANUFACTURINIG, U.S. ENVIRONMENTAL COMMERCIAL,PROTECTION MINING AND Permits Program AGENCY SILVICULTURE OPERATIONS I. OUTFALL LOCATION For each outfall, list the latitude and longitude of its location to the nearest 15 seconds and the name of the receiving water. A. OUTFALL NUMBER B. LATITUDE _ __ C. LONGITUDE (list) 1. DEG. 2. MIN. 3. SEC. 1. DEG. 2. MIN. 3. SEC. 0. RECEIVING WATER (name) D 101 35.00 12.00 35.00 85.00 .5.00 14.00 Tennessee River 11.FLOWS, SOURCES OF POLLUTION, AND TREATMENT TECHNOLOGIES A. Attach a line drawing showing the water flow through the facility. Indicate sources of intake water, operations contributing wastewater to the effluent, and treatment units labeled to correspond to the more detailed descriptions in Item B. Construct a water balance on the line drawing by showing average flows between intakes, operations, treatment units, and outfalls. If a water balance cannot be determined (e.g., for certain mining activities), provide a pictorial description of the nature and amount of any sources of water and any collection or treatment measures. B For each outfall, provide a description of: (1) All operations contributing wastewater to the effluent, including process wastewater, sanitary wastewater, cooling water, and storm water runoff; (2) The average flow contributed by each operation; and (3) The treatment received by the wastewater. Continue on additional sheets if necessary.

1. OUT- 2. OPERATION(S) CONTRIBUTING FLOW 3. TREATMENT FALL b. AVERAGE FLOW b. LIST CODES FROM NO. (lst) a. OPERATION (list) (include units) a. DESCRIPTION TABLE 2C-1 101 Discharges include drainage from: 490.7923 WOO Discharge to Surface Water 4

                                                                    .                                                                                                         A Low volume waste treatment pond                                                         Sedimentation   (settling)

(ou atale r03) a (1.1906 MWD) U Discharge from metal cleaning 4 waste ponds (IMP outfall 107) Turbine building sump Storm water runoff Neutral Waste Sump CCW Discharge channel: (1447.0140 MODI Raw cooling water system Disinfection lother) 2 Diesel fuel recovery trench groundwater & high pressure fire protection potable water Storm water runoff cooling tower blowdown basin: 140. 413 61 ERCW system Disinfection (other) 2 a cooling towers(closed/helper mode) Store war r r::noff Liquid radwaste treatment system Ion Exchange. 2 Multimedia Filtration 1Q Yard drainage pond: Sedimentation (settling) 12.125 MGlD) 1 U Constr./Demo.landfill storm water runoff Switchyard runoff Various building heat loads Auxillary building heat loads Yard drainage system Storm water runoff (0.0218 MGD) Precipitation minus evaporation (0.0273 Monl 4EP FtCIAL USE ONLY (effluent guidelines sub-categories) om31-C(-9)PG* f4-COTNEO EES EPA Form 3510-2C (8-90) PAGE 1 of 4 CONTINUE ON REVERSE

CONTINUED FROM THE FRONT C. Except for storm runoff, leaks, or spills, are any of the discharges descnbed in Items Il-A or B intermittent or seasonal? YES (complete thefollowing table) NO (go to Section 111)

3. FREQUENCY 4. FLOW 4 1. OUTFALL

2. OPERATION(s)

CONTRIBUTING FLOW

a. DAYS PER WEEK (speify

b. MONTHS PER YEAR

a. FLOW RATE (in mgd)

1. LONG TERM 2. MAXIMUM B. TOTAL VOLUME (Qecifywith unito)

1. LONG TERM 2. MAXIMUM C. DURATION NUMBER (lit) (lio) aoerage) (specify a-e-age) AVERAGE DAILY AVERAGE DAILY (in days) 101 Metal Cleaning Waste Ponds 0 .0022 0 .0504 When rainwater collects in the metal cleaning waste ponds, the ponds are discharged (IMP outfall 107) into the low volume waste treatment ILVWT) pond which discharges through IMP outfall 103 into the diffuser pond (outfall 101). The metal cleaning waste ponds discharge an average of 10-12 hours per day, approximately 21 days out of the year with an ave.

flow of 39 gpm. NOTE: The metal cleaning waste pond has not discharged into the LVWT pond since 5/31/2006. Ill.PRODUCTION-A. Does an effluent guideline limitation promulgated by EPA under Section 304 of the Clean Water Act apply to your facility? W] YES (complete Item 111-B) E NO (go to Section IV) B. Are the limitations in the applicable effluent guideline expressed in terms of production (or other measure of operation)? LI YES (complete Item 11-C) . NO (go to Section IV) C. If you answered "yes" to Item Ill-B, list the quantity which represents an actual measurement of your level of production, expressed in the terms and units used in the applicable effluent guideline, and indicate the affected outfalls.

1. AVERAGE DAILY PRODUCTION 2. AFFECTED OUTFALLS

a. QUANTITY PER DAY b. UNITS OF MEASURE c. OPERATION, PRODUCT, MATERIAL, ETC. (list outfall numbers)

(specify) 4 IV. I EMENTS A. Are you now required by any Federal, State or local authority to meet any implementation schedule for the construction, upgrading or operations of wastewater treatment equipment or practces or any other environmental programs which may affect the discharges described in this application? This includes, but is not limited to, permit conditions, administrative or enforcement orders, enforcement compliance schedule letters, stipulations, court orders, and grant or loan conditions. DYES (complete thefolio wing table) [] NO (go to item IV-B) 1 IDENTIFICATION OF CONDITION, 2. AFFECTED OUTFALLS 4. FINAL COMPLIANCE DATE AGREEMENT, ETC. 3. BRIEF DESCRIPTION OF PROJECT

a. NO, b. SOURCE OF DISCHARGE a. REQUIRED b. PROJECTED 4 TI-'O iUNAL: You may attach additional sneets descrioing any additional water pollution control programs (or otner environmental projects which may affect your discharges) you now have underway or which you plan. Indicate whether each program is now underway or planned, and indicate your actual or planned schedules for construction.

               -  MARK "X" IF DESCRIPTION OF ADDITIONAL CONTROL PROGRAMS IS ATTACHED PAGE 2 of4                                                                 CONTINUE ON PAGE 3 EPA Form EPA    Form 3510-2C     (8-90) 3510-2C (8-90)                                                      PAGE 2 of 4                                                                CONTINUE.ON PAGE 3

EPA I.D. NUMBER (copyfrom Item I ofForm 1) CONTINUED FROM PAGE 2 I TrN5 64 0 02 DS 04 1 INTAKE AND EFFLUENT CHARACTERISTICS

           & C: See instructions before proceeding - Complete one set of tables for each outfall - Annotate the outfall number in the space provided.

I NOTE: Tables V-A, V-B, and V-C are included on separate sheets numbered V-1 through V-9. D. Use the space below to list any of the pollutants listed in Table 2c-3 of the instructions, which you know or have reason to believe is discharged or may be discharged from any nutfall For everyj nolhiitant von list briefly dlesrndhe the rasonns von helieve itto he nre~sent and report anY analtiC~al data in your n~ossession

1. POLLUTANT 2. SOURCE 1. POLLUTANT 2. SOURCE Dimethylamine Steam Generator. Layup (The use of dimethylamine will not result in detectable quantities at outfall 101 for the following reason:

The maximum dimethylamine concentration in the steam generators is 10ppm during layup. The capacity of each unit's four steam generators is approximately 80,000 gallons. Steam generators can be drained down at a rate of 400 gpm.. Both units' steam generators are not drained down simultaneously. Therefore, the maximum concentration of dimethylamine at outfall 101 would be 7 0.00 ppm. The MDL for dimethylamine is 0.1ppm) V1. POTENTIAL DISCHARGES NOT COVERED BY ANALYSIS Is any pollutant listed in Item V-C a substance or a component of a substance which you currently use or manufacture as an intermediate or final product or byproduct? dn [E] YES (list all such pollutants beloiv ) . ] NO (go to Item V7-B) Urn p I EPA Form 3510-2C (8-90) PAGE 3 of 4 CONTINUE ON REVERSE

CONTINUED FROM THE FRONT VII. BIOLOGICAL TOXICITY TESTING DATA Do you have any knowledge or reason to believe that any biological test for acute or chronic toxicity has been made on any of your discharges or on a receiving water in relation to your discharge within the last 3 years? A"& 21 YES (identify the test(s) and describe their purposes below) D NO (go to Section Vil1) d IIw-Per the requirements of the SQN NPDES Permit No. TN 0026450, IC25 toxicity testing has been conducted. on discharges from Outfall 101 once per year when oxidizing biocides are being used and once per year when non-oxidizing biocides are being used. Results are submitted to the Division of Water Pollution Control on the appropriate Discharge Monitoring Reports. VIII. CONTRACT ANALYSIS INFORMATION Were any of the analyses reported in Item V performed by a contract laboratory or consulting firm? YES (list the name, address, and telephone n.urmber of andpollutants analyzed by, NO (go to Section IX) each such laboratoryorfirnm below) A.NAMEC. TELEPHONE D. POLLUTANTS ANALYZED (areacode & no.) (list) Environmental Science Corp. 12065 Lebanon Road (615)758-5858 All except total residual (ESC) Mt. Juliet, TN 37122 (600)767-5859 chlorine, pH, mercury, and sulfite Mercury One, Ltd. 2241 Pinnacle Parkway, Suite B (330)963-0843 mercury Twinsburg, OH 44087 IL. CERTIFICATION-I certify under penalty of law that this document and all attachments were preparedunder my direction or supervision in accordance with a system designed to assure that qualified personnel property gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate,and complete.'l am aware that there are significant penaltiesfor submitting false information, including the possibility of fine and imprisonmentfor knowing violations. A. NAME & OFFICIAL TITLE (type orprint) B. PHONE NO. (area code & no.) Timothy P. Cleary, Site Vice President, Sequoyah Nuclear Plant (423) 843-7001 D. DATE SIGNED 21 .*pAo9 I PAGE 4 of 4

PLEASE P TYPE IN THE UNSHADED AREAS ONLY You may report some or all of this information I.D. NUMBER (copyfrom Item I of Form 1) on separate 's (use the same format) instead of completing these pages. 'TN5640020504 SEE INSTRUCTIONS. TN60000

                                                                                                                                                                                                                                 )UTFALL NO.

V. INTAKE AND EFFLUENT CHARACTERISTICS (continued from page 3 of Form 2-C) 101 PART A -You must provide the results of at least one analysis for every pollutant in this table. Complete one table for each outfall. See instructions for additional details.

3. UNITS 4. INTAKE

2. EFFLUENT (specify ifblank) (optional)

b. MAXIMUM 30 DAY VALUE c. LONG TERM AVRG, VALUE .. a. LONG TERM

a. MAXIMUM DAILY VALUE (ifavailable) (i/available) AVERAGE VALUE P (1) (1) . d. NO. OF a. CONCEN- (1 b. NO. OF 1.-POLLUTANT. CONCENTRATION (2) MASS CONCENTRATION 1(2) MASS (1) CONCENTRATION (2) MASS ANALYSES TRATION b. MASS CONCENTRATION 12)

MASS ANALYSES I _ _ _ __ COCETATO 1_ (2)_MASS__ ANALYSES__

a. Biochemical Oxygen

                                       <5.0                                                                                                                         1           . mg/L Demand (HOD)                                                                                                                                                                                                      <5.0                              I

b. Chemical Oxygen Demand (COD) <20 1 mg/L <20

c. Total Organic Carbon (TOC) 1.95 1 mg/L 3.2 1

d. Total Suspended Solids (TSS) 5.3 7.65 17 mrg/L 2.9 1

e. Ammonia (ayN) <0.10 1 mg/-L <0 . 10 1 VALUE VALUE VALUE VALUE

f. Flow 1663 1654 1491 366 MGD 1595 1

g. Temperature VALUE. VALUE VALUE VALUE (winter) 2B.3 15 .4 15.5 183 °C N/A

h. Temperature VALUE VALUE VALUE VALUE (summner) 37 .6 26.1 26.1 184 29.75 1 MINIMUM MAXIMUM M)NIMUM MAXIMUM

i. pH ' 6.8S 8.38 N/A N/A STANDARD UNITS 67 PART B- Mark "X" in column 2-a for each pollutant you know or have reason to believe is present. Mark "X" in column 2-b for each pollutant you believe to be absent. If you mark column 2a for any pollutant which is limited either directly, or indirectly but expressly, in an effluent limitations guideline, you must provide the results of at least one analysis for that pollutant. For other pollutants for which you mark column 2a, you must provide quantitative data or an explanation of their presence in your discharge. Complete one table for each outfall. See the instructions for additional details and requirements. I

2. MARKVX" 3. EFFLUENT 4. UNITS

   .POLLUTANT                                                                      r                                     r                                    T                t                   I          1

b. MAXIMUM 30 DAY VALUE c. LONG TERM AVRG. VALUE a. LONG AND a. MAXIMUM DAILY VALUE (i/available) (ifavailable)

a. b..

CAS NO. BELIEVED BELIEVED d. NO. OF a. CONCEN-(1) CONCENTRATION (21 MASS (1) (1) (1) (/available) PRESENT ABSENT CONCENTRATION (21 MASS CONCENTRATION 1 (2) MASS ANALYSES TRATION b. MASS CONCENTF

a. Bromide 1 (24959-67-9) <1.O 1 1 g/L< 1.0

b. Chlorine, Total Residual x <0 .07 <0 .05 296 mg/L <0 .05

c. Color 7 .5 1 pCU 3 .0

d. Fecal Colitorm <244. 1 /100mL <12

e. Fluoride (16984-48-8) <0. 10 1 mg/L <0.10

f. Nitrate-Nitrite

• 1 (asN) 0.165 1 mg/L <0 .1 0 EPA Form 3510-2C (8-90) PAGE V-1 CONTINUE ON REVERSE

ITEM V-B UED FROM FRONT k

2. MARK "X" 3. EFFLUENT 4. UNITS 5. INTAKE

1. POLLUTANT b. MAXIMUM 30 DAY VALUE c. LONG TERM AVRG. VALUE a. LONG TERM AND a, b. a. MAXIMUM DAILY VALUE (ifavailable) .(ifavailable) AVERAGE VALUE CAS NO. BELIEVED BELIEVED (1) (1) (1) d. NO. OF a. CONCEN- (1) b. NO. OF (ifavailable) PRESENT ABSENT CONCENTRATION (2) MASS CONCENTRATION (2)IMASS CONCENTRATION (2) MASS ANALYSES TRATION b. MASS CONCENTRATION (2) MASS ANALYSES

g. Nitrogen, Total Organic (as <0.36 1 mg/L <0.44 1 N) I

h. Oil and <5.24 16 mg/L <5.0 1 Grease <5.0 I Phosphorus 0

(as P), Total 0.10 1 mg/L <0. 10 (7723-14-0), _1 1

j. Radioactivity .

(1) Alpha. Total X <4.08 1 pCi/L <4 .00 1 (2) Beta, Total X 3.34 pCi/L 1 2.58 1 (3) Radium, Total X (4) Radium 226, Total

k. Sulfate (as SO,)

(14808-79-8) 12.5 1 ag/L 13.0 1

1. Sulfide (asS) 0

                                           <0 . 050                                                                                 1        mg/L                    <0.050                             1

m. Sulfite (as So,)

(14265-45-3) 22.25 1 mg/L 1.5 1

n. Surfactants X '<0.10 mg/L <0.10 1

o. Aluminum, Total (7429-90-5) 0. 20 5 lg/L 0.10 1

p. Barium, Total X (7440-39-3) x 0.036 1 mg/L 0.024 1

q. Boron, Total (7440-42-8). . <0.20 <0.20 7 mg/L <0.20 1

r. Cobalt, Total (7440484) <0.0010 1 mg/L <0. 0010 1

s. Iron, Total (7439-89-6) 0.18 "1 mg/L <0.10 1

t. Magnesium, Total (7439-95T) 5.05 1 mg/L 4.7 1

u. Molybdenum, Total X (7439-98-7) <0. 0050 mg/L <.0. 0050

v. Manganese, Total 0 . 8015 1 mg/L 0.038 1

w. Tin, Total (7440-31-5) <0. 0010 . 1 mg/L 0.0024 1

x. Titanium, Total X3<0.010 1 mg/L <0.010 1 EPA7For 321-6) (890 PAE<2CNIU NPG -

EPA Form 3510-2C (8-90) PAGE V-2 CONTINUE ON PAGE V-3

EPA I.D. NUMBER (copyfrom Iern I of Form 1) OUTFALL NUMBER CONTINUED FROM PAGE 3 OF FORM 2-C TN5640020504 101 I PART C - If you are a primary industry and this outfall contains. process wastewater, refer to Table 2c-2 in the instructions to determine which of the GC/MS fractions you must test for. Mark "X" in column 2-a for all such GC/MS fractions that apply to your industry and for ALL toxic metals, cyanides, and total phenols. If you are not required to mark column 2-a (secondary industries, nonprocess wastewater outfalls, and nonrequired GC/MS fractions), mark "X" in column 2-b for each pollutant you know or'have reason to believe is present. Mark "X" in column 2-c for each pollutant you believe is absent. If you mark column 2a for any pollutant, you must provide the results of at least one analysis for that pollutant. If you mark column 2b for any pollutant, you must provide the results of at least one analysis for that pollutant if you know or have reason to believe it will be discharged in concentrations of 10 ppb or greater. If you mark column 2b for acrolein, acrylonitrile, -2,4 dinitrophenol, or 2-methyl-4, 6 dinitrophenol, you must provide the results of at least one analysis for each of these pollutants which you know or have reason to believe that you discharge in concentrations of 100 ppb or greater. Otherwise, for pollutants for which you mark column 2b, you must either submit at least one analysis or briefly describe the reasons the pollutant is expected to be discharged. Note that there are 7 pages to this part: please review each carefully. Complete one table (all 7 pages) for each outfall. See instructions for additional details and requirements.

2. MARK "X" 3. EFFLUENT 4. UNITS 5. INTAKE (optional)

1. POLLUTANT b. MAXIMUM 30 DAY VALUE c. LONG TERM AVRG. a. LONG TERM ANb. c. a. MAXIMUM DAILY VALUE (i[available) VALUE (ifavailable) AVERAGE VALUE CAS NUMBER- TESTING BELIEVED BELIEVED d. NO. OF a. CONCEN- (t) NO. OF (i[available) REQUIRED PRESENT -ABSENT CONCENTRATION (2)MASS CONCENTRATION (2)MASS CONCENTRATION (2)MASS ANALYSES TRATION b.-MASS CONCENTRATIO ANALYSES METALS, CYANIDE, AND TOTAL PHENOLS 1M. Antimony, Total <0.0010 (7440-36-0) . . <0.0010 1 mg/L <

2M. Arsenic, Total 1 (7440-38-2) X 0.0010 5 mg/L <0 ,0010 3M. Beryllium, Total (7440-41-7) <0. 0010 1

• mg/L <0,0010 1 4M. Cadmium, Total (7440-43-9) X <0. 00050 mg/L <0 .00050 1 1

5M. Chromium, Total (7440-47-3) < 0 . 00 !'0 1 mg/L <0 . 00 10 1 6M. Copper, Total (7440-50-8)0.0018 1 mg/L 0.0016 1 7M. Lead, Total (7439-92-1) . <0 . 0010 10 mg/L <0. 0010 ' 1 8M. Mercury, Total 1 (7439-97-6) /\ 1:17 ng/L 133 9M. Nickel, Total X<0.00245 (7440-02-0)<1 mg/L 0.0010 1 10M. Selenium, Total (7782-49-2) X <0.0010 1 mg/L <0.0010 1 11M. Silver, Total (7440-22-4) . <0.00050 1 mg/L <0.00050

                                                                                                                                                                                                        <                                 1 12M. Thallium, Total (7440-28-0)           /N                               <0.0010                                                                                              1-       mg/L                          <0. 0010                         1 13M. Zinc, Total                                              <<

(7440-66-6) ,<0.0105 1 mg/L <0.010 1 14M. Cyanide, Total (57-12-5) <0.0050 5 1 mg/L <0. 0050 1 15M. Phenols, Total <0.040 1 mg/L <0. 040 1 DIOXIN 2,3,7,8-Tetra- " \ 7 DESCRIBE RESULTS chlorodibenzo-P-Dioxin (1764-01-B) EPA Form 3510-2C (8-90) PAGE V-3 CONTINUE ON REVERSE

COTNUENAIM THE FRONT _____

12. MARK 'X 3, EFFLUENT 4. U. INTAKE4.UNIT 1..POLLUTANT MAX MUM 30 DAY VALUE c. LONG TERM AVRG. a. LONG TERM AND a. b. I . a. MAXIMUM DAILY VALUE (ifavailable) VALUE (ifavailable) AVERAGE VALUE COuNCEN- I

a. CONCEN- I I b. NO. OF CAS NUMBER TESTING [BELIEVED BELIEVED I[ - d. NO. .OOF)a.

d.N MASS NO OF (iavailable) REQUIRED PRESENT ABSENT CONCENTRATION (2 MASS CONCENlCNETRTO ASS CNCENT ()MSSCNETRTO7()MS ANALYSES TRATION b. MbA CONCENT:RATION (2) MASS ANALYSES GC/MS FRACTION - VOLATILE COMPOUNDS IV. Accrolein m (107-02-8) / 0.050 Mg/L <0.050 0 2V. Acrylonitrile (107-13-1) / 1<0 .010 1 mg/L <0.010 0 3V. Benzene (71-43-2) <0 . 0010 1 mg/iL <0 . 0010 4V. Bis (Chvoro- - meihy/) Ether (542-88-1) x 5V. Bromoform 75-25-2) <0. 0010 1 rng/L <0. 0010 6V. Carbon Tetrachloride, <0 .0010 1 56-23-5) mg/ 0.0010 7V. Chlorobenzene X ci0.01 1 Iv <0.0010 (108-90-7) < 0 mg/. 1 8V. Chlorodi-bromomethane < 0 . 0010 0 1 mg/L < 0.0 010 (124-48-1) 9V. Chloroethane (75-00-3) <0. 0050 1 mg/L <0 .0050 1 1OV. 2-Chloro-ethylvinyl Ether <0.050 1 mgL <0.0501 (110-75-8) - <0. 050 mg/L <0. 050 1 1 V. Chloroform (67-66-3) <0. 0050 1 mg/L -< <0. 0050 1 12V. Dichloro-bromomethane < (75-27-4) <0. 0010 1 mg/L <0 .0010 13V. Dichioro-difluoromethane <0.0050 1 mgiL <0.0050

                                                                                                                                                                                  .0 5                      1 (75-71-8)                                                    5_____.<         __00 14V. 1,1-Dichloro-     \,

ethane (75-34-3) /N <0 . 0010 - 1 mg/L <0 . 0010 1 15V. 1,2-Dichloro- \ ethane (107-06-2) <0.0010

                                                   </                                                                                      1          mg/L                    <0 . 0010                     1 16V. 1, 1-Dichloro-ethylene (75-354)      /                           <0 .0010                                                                                 1          mg/L                    <0 . 0010                     1 17V. 1,2-Dichloro-    X propane (78-87-5)                                  <0    0 01                                                                                           rmg/L                  < 0.0 010                     1 18V. 1,3-Dichloro-propylene                                           <0 . 0010                                                                                          Mg/L                    <0 . 0010                     1 (542-75-6) 1 19V. Ethylbenzene                                  <

(I00-41-4) < 0.0010 1 mg/L <0.0010 1 20V. Methyl Bromide (74-83-9) /\ <0.0050 1 mg/L <0. 0050 1 1 21V. Methyl Chloride (74-87-3) <0. 0025 1g/0 2 EPA Form 3510-2C (8-90) PAGE V-4 CONTINUE ON PAGE V-5

GC/MS FRACTION - VOLATILE COMPOUNDS (confinueaj 22V. Methylene Chloride (75-09-2) < 0 . 0050 05 0 1 1 23V. 1,1,2,2-Tetrachloroethane <0 (79-34-5) <0 0010 1 mg/L <0.0010 1 24V. Tetrachloro- < 1 ethylene (127-18-4) ,<0.0010 <0.0010 1 1/ 25V. Toluene 0 1 mg/L <0 . 0050 (108-88-3) <0 0050 26V. 1,2-Trans-Dichloroethylene <0 0 0 10 1 mg/L <0.0010 1 (158-60-5) x 0 27V. 1,1,1-Trichloro-ethane (71-55-6) /* <0.0010 1 mg/L <0, 0010 1 28V. ethane1,1,2-Trichloro-(79-00-5) X < 00. 00 0 10 <0.0010 1 1 rag

                                                                               /L<0          0 0 1 01 29V Trichloro-                                  0 ethylene (79-01-6)        /<0.0010                                        1  rg/L      <0.0010                      1 30V. Trichloro-fluoromethane           x                   <0.0050                       1  mg/L      <0.0050                      1 (75-69-4)                        _                                                                 -7     --

31V. Vinyl Chloride X <0.0010 1 00 (75-01-4) <0 .00101 mg/L < 0.0010 1 GC/MS FRACTION - ACID COMPOUNDS 1A. 2-Chlorophenol 0 (95-57.8) <0 . 0 10 1 mg/L <0. 011 1 2A. 2,4-Dichloro- 01 Mg/L <0.011 1 phenol (120-83-2) x<0010 3A. 2,4-Dimethyl- \a phenol (105-67-9) <0.010 1 mg/TL <0.011 1 4A. 4,6-Dinitro-O-Cresol (534-52-1) ) <0.010 1 mg/L <0.011 1 5A. 2,4-Dinitro- <0 0 01/L<

                                                                                             .1 phenol (51-28-5)        .<0.010                                          1  mg/L       <0.011                      1 6A. 2-Nitrophenol                            <

(88-75-5) x<0.010 1 mg/L <0.011 1 7A. 4-Nitrophenol 0 (100-02-7) \<0 0 10 1 mg/L <0 . 011 1 8A. P-Chloro-M- 1 <0011 1 Cresol (59-50-7) <0 . 010 Img 9A. Pentachloro- <0.010 1 mr/L <0.011 1 phenol (87-86-5) < 0___0_l 0_  ! mg/L <_0___11_ 10A. Phenol (108-95-2) <00 1 mg/L . <0.011 1 '11A. 2,4,6-Trichloro- 0 1 11 phenol (88-05.2) x<0.010 1 mg/L <0.011 1 EPA Form 3510-2C (8-90) PAGE V-5 CONTINUE ON REVERSE

CONTJNUfftM THE FRONT

1. POLLUTANT "a 2. MARK "X" 3. EFFLUENT'

b. MAXIMUM 30 DAY VALUE a

c. LONG TERM AVRG.

1 4. UNITS a

5. INTAKE (o7W.)

a. LONG TERM 1d.

AND a. b. c. a. MAXIMUM DAILY VALUE (ifavailable) VALUE (ifavailable) AVERAGE VALUE CAS NUMBER TESTING BELIEVED BELIEVED (1) (1) (1) NO. OF a. CONCEN- (1) I b. NO. OF (if available) REQUIRED PRESENT ABSENT CONCENTRATION (2) MASS CONCENTRATION (2) MASS "_CONCENTRATON_(2)MASS ANALYSES TRATON _ b. MASS CONCENTRATON_(2) MASS ANALYSES GC/MS FRACTION - BASE/NEUTRAL COMPOUNDS 103 Acenaphthene (83-32-9) x <0.0010

                                                        <.0 1        mg/L                  <0.0011                         1 gL0                          01

28. Acenaphtylene (208-96-8) 50 .0010

                                                        <                                                                                1        mg/L                  <0.0011                         1 3B. Anthracene                                           <     0                                                                          1                              <0.o0i1                          1 (120-12-7)                                               <0.0010                                                                          1,       mg/                   <0.0011_1

48. Benzidine (92-87-5) <0. 051 1 mg/L <0.054 1 5B. Benzo (a)

Anthracene X 0.0010 1 mg/L <0.0011 1 (56-55-3) <0. 010i m/L 011 _. 6B. Benzo (a) Pyrene (50-32-8) <0.0010

                                                        <                                                                                1        mg/L                  <0.0011                          1 7B. 3,4-Benzo-fl(o2anth9ee            X                                <0 .0010                                                                         1        mg/L                  <0.0011                          1 8B. Benzo (ghi)

Perylene (191-24-2) <0.0010

                                                        <-                                                                               1        mg/L                  <0.0011                          1 9B. Benzo (k)

Fluoranthene 1 (207-08-9) <0.0010 1 mg/L <0.0011 108. Bis (2-Chloro-ethoxy) Methane 0 (111-91-1) <0.010 1 mg/L <0. 011 1 11B. Bis (2-Chloro-ethyl) Ether 0 111-44) <0.010 1 mg/L <0.011 1 12B. Bis (2. Chloroisopropyl) <0.010 1 m/L <0.011 1 Ether (102-80-1) __0_1_mg/L_<0_. < 0x Oli_1 13B, Bis (2-Elhyl-he-8yl)hhalate <0.00125 1 mg/L <0.0011 1 14B. 4-Bromophenyl Phenyl Ether < 101-55-3) <0010 1 mg/L <0 11 1 15B. Butyl Benzyl 1 Phthalate (85-68-7) x <0 . 0010 1 rg/L < 0 . 0 0 11 1 168.2-Chloro-naphthalene < (91-58-7) <0 . 01a 1 mg/L <0.0l1 1 17B, 4-Chloro-phenyl Phenyl Ether X (7005-72-3) <0. 010 1 mg/L < 0.0 11 1 18B. Chrysene h (218-01-9) <0.0010 1 mg/L <0.0011 1 19B. Dibenzo (ah) Anthracene 0 (53-70-3) x<0.0010 mg/ <0._0011_1 20B. 1,2-Dichloro- < benzene (95-50-1) <_0.0_0_10 1_l mg_/_L <_0_._0_0_1_0 1 218, 1,3-Di-chloro- 1 benzene (541-73-1) <0.0010

                                                        <                                                                                1        mg/L                  <0.0010                         1 EPA Form 3510-2C (8-90)                                                                                 PAGE V-6                                                                       CONTINUE ON PAGE V-7

CONTINUEJMW PAGE V-6

2. MARK 'X" 3. EFFLUENI 4. UNITS 5. INTAKE 1.POLLUTA T b. MAXIMUM 30 DAY VALUE I c.LONG TERMAVRG a. LONG TERM AND a. b. c. a. MAXIMUM DAILY VALUE (Vfa'aabe) VALUE (ifavailable) AVERAGE VALUE CAS NUMBER TESTING BELIEVED BELIEVED (1) (1) (1) d. NO. OF a CONCEN M S b. NO. OF (ffavailable (iavilbl) EQIRDPRESENT REQUIRED PRESENT ABSENT CONCENTRATION1 (2) MASS ABSENTMASS(AS)GMNSE CONCEN(TRATION1 (2) MS OCNRTOMASS ASINLSS!RTO ANALYSES TRATION .MS b.MS CONCENTRATION 1(2) MASSANLSS ANALYSES GC/MS FRACTION - BASE/NEUTRAL COMPOUNDS (continued) 228. 1,4-Dichloro- <0 ;i01 1 m'L <0.0010 1 benzene (106-46-7) < 0 0g, 23B. 3.3-Dichloro- <0.011 benzidine (91-94-1) 1

                                                      *0.010                                                                              1         mg/L 24B. Diethyl                                                                                                                               1                               <0.0011 Phthalate (84-66-2)                                                                                                                                                                                    1
                                                    <I0.0010                                                                              1g/

25B. Dimethyl Phthalate <0.0010 1 mg/L <0.0011 (131 3) 1

                                                     <0. 0010                                                                             i         mg/L                  <0. 0011                     i 26B. Di-N-Butyl Phthalate (84-74-2)        /<0.0011                                                                                                       1         mg/L                  <0.0011                      1 278. 2,4-Dinitro-                                         00                                                                               1         m 1

L <0.011 toluene (121-14-2) 1

                                                      <0                                                          .010 28B. 2,6-Dinitro-                                        00                                                                                1           g/.L                 <0011                       1 toluene (606-20-2)                                     <0 . 0 1 0                                                                          1 29B. Di-N-Octyl 1

Phthalate (117-84-0) <0 . 0010 1 mg/L <0.0011 1 30B. 1,2-Diphenyl-hydrazine (as Azo- 0 1 mg/L <0.011 1 benzene) (122-66-7) <0 . 010 31B. Fluoranthene <I 1 mc/L <0.0011 1 (206-44-0) <0.0010 32B. Fluorene (86-73-7) <0. 0010 1 mg/L <0.0011 1 33B. Hexachloro- I benzene (118-74-1) <0 .010 1 Mg/L <0.011 1 3346.Hexachloro- . butadiene (87-68-3) <0.010

                                                       <                                                                                  1         mg/L                   <0 . 011                    1 35B. Hexachloro-(77-47A) cyclopentadiene           X<0.010                      <0001x/                                                                             1         mg/L                     0
                                                                                                                                                                           <0.011  1                   1 36B Hexachloro-        .

ethane (67-72-1) <0 0 10 1 mg/L < 0 . 0 11 1 376. Indeno (1,2,3-cd) Pyrene <0 0010 <0.0011 1 (193-39-5) <0 .0010 1 . m g /L < 0 .0011 I 386. Isophorone 0 (78-59-1) <0 0 10 1 mg/L <0.011 396. Naphthalene < 0.00 10 1 <0.0011 (91-20-3) 1

                                                    <0 . 0010                                                                             1         mg/L                  <0. 0011                     1 40B. Nitrobenzene (98-95-3)                                              <0.010                                                                              1 1         mg/L                   <0 . 0ll                    1 41B. N-Nitro-sodimethylamine                                        <0. 0                                                                               1 (62-75-9)                                                                                                                                            mg/L                   <0 . 054                    1
                                                      <0,051                                                                              1         mg/L                   <0. 054                     1 426. N-Nitrosodi-N-Propylarnine            X                                 .010 E621-64-7)                                             <orm 1g/L-<0(6-10 1

EPA Form 3510-2C (8-90) CONTINUE ON REVERSE PAGE V-7

SINU M THEFRONT

2. MARK X" 3. EFFLUENT 4. UNITS 5. INTAKE

1. POLLUTANT b. MAXIMUM 30 DAY VALUE c. LONG TERM AVRG.

AND CAS NUMBER a TESTING b. BELIEVED c. BELIEVED

a. MAXIMUM DAILY VALUE favailable) 71-- -(

VALUE (ifavailable)

d. NO. OF Ia. CONCEN-

a. LONG TERM AVERAGE VALUE (1) b NO OF (ifavailable) REQUIRED PRESENT ABSENT CONCENTRATION (2) MASS CONCENTRATION (2) MASS CONCENTRATION] (2)MASS ANALYSES TRATION b. MASS CONCENTRATION (2) MASS JANALYSES GC/MS FRACTION - BASE/NEUTRAL COMPOUNDS (continued) 438. N-Nitro-sodiphenylamine (86-30-6) - <0.010 0 1 1 mg/L g/ <0.011 0 1 1 448. Phenanthrene (85-01-8)

X <0. 0010 1 mg/L <0.0011 1 45B. Pyrene (129-00-0) <0.0010 1 mg/L <0. 0011 1 46B. 1,2,4-Ti-chlorobenzene " <0.010 (120-82-1) x <0.T01071 mg/L <0.011 1 GC/MS FRACTION - PESTICIDES 1P. Aldrin (309-00-2) x 2P. a-BHC (319-84-6) x 3P. P-BHC (319-85-7) X 4P. "-BHC

                                                                                                                                                                                                         /

(58-89-9) x 5P. 5-BHC (319-86-8) x 6P. Chlordane X (57-74-9) x 7P. 4,4'-DDT (50-29-3) X 8P. 4,4'-DDE (72-55-9) X 9P. 4,4'-DDD, (72-54-8) _ lOP. Dieldrin (60-57-1) 11P. a-Enosulfan (115-29-7) x 12P. 3-Endosullan (115-29-7) x 13P. Endosulfan Sulfate (1031-07-8) x 14P. Endrin (72-20-8) 15P. Endrin Aldehyde (7421-93-4) X 16P. Heptachlor (76-44-8) X EPA Form 3510-2C (8-90) PAGE V-8 CONTINUE ON PAGE V-9

EPA ID. NUMBER (cop) fromn I/em] ffForn* I) W UTFALL NUMBER TN5640020504 . 101 CONTINUED FROM PAGE V-8 I

2. MARK "X". 3. EFFLUENT 4. UNITS 5. INTAKE (optional)

1. POLLUTANT AND a. b. c. b. MAXIMUM 30 DAY VALUE C.VALUE LONG TERM AVRG. a. LONG TERM

a. MAXIMUM DAILY VALUE (if available) (if available) AVERAGE VALUE CAS NUMBER TESTING BELIEVED BELIEVED 1 d, NO. OF a. CONCEN- (1)b. NO. OF (f available) REQUIRED PRESENT ABSENT CONCENTRATION (2) MASS CONCEN TRATION1 (2)MASS CONCENTRATION (2)MASS ANALYSES TRATION b. MASS (2) MASS ANALYSES GC/MS FRACTION - PESTICIDES (continued) 17P. Heptachlor Epoxide (1024-57-3) 18P. PCB-1242 (53469-21-9) <0. 005i 1 mg/L <0. 0054 1 19P. PCB-1254 <

(11097-69-1) x<0.o005 1 mg/L <0.0054 1 20P. PCB-1221 0 (11104-28-2) <0.0051 1 mg/L <0. 0054 1 21P. PCB-1232 (11141-16-5) <0 . 0051 1 mg/L <0 . 0054 1 22P. PCB,1248 (12672-29-6) x <0. 0051 1 mg/L <0. 0054 1 23P. PCB-1260 (11096-82-5) <0. 0051 1 mg/L <0. 0054 1 24P. PCB-1016 (12674-11-2) <0.0051 1 mg/L <0. 0054 1 25P. Toxaphene (8001-35-2) _ EPA Form 3510-2C (8-90) PAGE V-9

EPA I.D. NUMBER (copy from Item I of.Form 1) Form Approved. OMB No. 2040-0086. Please print or type in the unshaded areas only. TN5640020504 Approval expires 3-31-98. 4 NPIDES

                                   ~APPLICATION C E PAEXISTING                                  MANUFACTURING, FOR PERMIT TO DISCHARGE WASTEWATER COMMERCIAL, MINING AND SILVICULTURE OPERATIONS ConsolidatedPermits Program

1. OUTFALL LOCATION For each outfall, list the latitude and longitude of its location to the nearest 15 seconds and the name of the receiving water.

A. OUTFALL NUMBER B. LATITUDE C. LONGITUDE (list) 1. DEG. 2. MIN. 3. SEC. 1. DEG. 2. MIN. 3. SEC. D. RECEIVING WATER (name) 103 IMP 35.00 8.00 17.00 85.00 8.00 1.00 Diffuser Pond II.FLOWS, SOURCES OF POLLUTION, AND TREATMENT TECHNOLOGIES A. Attach a line drawing showing the water flow through the facility. Indicate sources of intake water, operations contributing wastewater to the effluent, and treatment units labeled to correspond to the more detailed descnptions in Item B. Construct a water balance on the line drawing by showing average flows between intakes, operations, treatment units, and outfalls. If a water balance cannot be determined (e.g., for certain mining activities), provide a pictorial description of the nature and amount of any sources of water and any collection or treatment measures. B For each outfall, provide a description of: (1) All operations contributing wastewater to theeffluent, including.process wastewater, sanitary wastewater, cooling water, and storm water runoff; (2) The average flow contributed by each operation; and (3) The treatment received by the wastewater. Continue on additional sheets if necessary.

1. OUT- 2. OPERATION(S) CONTRIBUTING FLOW 3. TREATMENT FALL b. AVERAGE FLOW NO. (list) a OPERATION (list) (include units) a. DESCRIPTION

            +                                                                    .

Dischargeo include drainage from: 1.1906 MGD Sedimentation setrtlino) I. I. Neutralization 4 Fsischurge from met~alcleaing waste pnords (outfall 1071 (0.0022 MCDI T urbine buildin q sum p: (1.0067 MGD) Turbine building floor and enuieent drains Condensate demineralizer regen, waste Neuttalizatior Secondary system leaks and draindowns Steam Generator blowdown CCS waste Miscellaneous equipment cooling Ice condenser waste Alum sludge ponds (WTP) Sedimentatiorn (settling) Gravity Thickenin2 Landfill Neutral waste sump (WTP) 10.1767 MCDI Storm water runoff (0.0008 MCDI _Precipitation minus evaporation 10.0042 MCDI 4 1 WICIAL USE ONLY (effluent guidelines sub-categories) EPA Form 3510-2C (8-90) PAGE 1 of 4 CONTINUE ON REVERSE

CONTINUED FROM THE FRONT C. Except for storm runoff, leaks, or spills, are any of the discharges described in Items II-A or B intermittent or seasonal? II YES (complete thefollowing table) Ej NO (go to Section I1I)

3. FREQUENCY 4. FLOW I 2. OPERATION(s)

a. DAYS PER WEEK b. MONTHS a. FLOW RATE (in mgd)

B. TOTALVOLUME (specoywith units)

1. OUTFALL CONTRIBUTING FLOW (Ipecify PER YEAR 1. LONG TERM 2. MAXIMUM 1. LONG TERM 2. MAXIMUM C. DURATION NUMBER (lit) (tit) aver)ge (specf average) AVERAGE DAILY AVERAGE DAILY (ia days)

Discharges from the metal cleaning 0.0022 0.0504 103 (IMP) waste treatment ponds (outfall 107 IMP) which includes batch discharges of chemical cleaning wates from various plant systems and accumulated storm water. NOTE: The metal cleaning waste ponds (outfall 107 IMP) has not discharged since 5/31/2006. Prior to this date, the metal cleaning wastes ponds discharged an average of 10-12hrs/day, approximately 21 days of the year at an average of 39 gpm. Ill. PRODUCTION- - - A. Does an effluent guideline limitation promulgated by EPA under Section 304 of the Clean Water Act apply to your facility? I t YES (complete fer I -I-B) [] NO (go to Section IV) B. Are the limitations in the applicable effluent guideline expressed in terms of production (or other measure of operation)? El YES (complete Item Ill-C) NO (go to Section IV) C. If you answered "yes" to Item Ill-B, list the quantity which represents an actual measurement of your level of production, expressed in the terms and units used in the applicable effluent guideline, and indicate the affected outfalls:

1. AVERAGE DAILY PRODUCTION 2. AFFECTED OUTFALLS

a. QUANTIT Y PER DAY b. UNITS OF MEASURE c. OPERATION, PRODUCT, MATERIAL, ETC. (Ati outfall numbers)

(specify) 4 I IROVEMENTS. A. Are you now required oy any Federal, Sitate *or local authority to meet any implementation scnedulIe ror the construction, upgrading or operations of wastewater treatment equipment or practices or any other environmental programs which may affect the discharges described in this application? This includes, but is not limited to, permit conditions, administrative orenforcement orders, enforcement compliance schedule letters, stipulations, court orders, and grant or loan conditions. E] YES (complete thefollowing table) Z NO (go to Item IV-B)

1. IDENTIFICATION OP CONDITION, 2, AFFECTED OUTFALLS 3 RE ECITO FPOET4. FINAL COMPLIANCE DATE AGREEMENT, ETC.3.BIFDSRPONFPOJC a.NO. b SOURCE OF DISCHARGE a. REQUIRED b.PROJECTED 4 ftOPTIONAL: You may attach additional sheets describing any additional water pollution control programs (or other environmental projects which may affect your ischarges) you now have underway or which you plan. Indicate whether each program is now underway or planned, and indicate your actual or planned schedules for construction.

LI MARK "X" IF DESCRIPTION OF ADDITIONAL CONTROL PROGRAMS IS ATTACHED EPA Form 3510-2C (8-90) PAGE 2 of 4 CONTINUE ON PAGE 3

S EPA I.D. NUMBER (copyfrom Item I of Form 1) ITN5640020504 ]I CONTINUAE AD FROMPAEN 2HRCEITC EVINTAKE AND EFFLUENT CHARACTERISTICS 4 I B, & C: See instructions before proceeding - Complete one set of tables for each outfall - Annotate the outfall number in the space provided. NOTE: Tables V-A, V-B, and V-C are included on separate sheets numbered V-1 through V-9. D. Use the space below to list any of the pollutants listed in Table 2c-3 of the instructions, which you know or have reason to believe is discharged or may be discharged erloutant rou list briefly descrihe the reasons vel hbelieve it to he nroreent and repnnrt anv analtical data in vour nossession from any oiltfall Fnr nerv

1. POLLUTANT 2. SOURCE 1. POLLUTANT 2. SOURCE Dimethylamine Steam Generator Layup (The use of dimethylamine will not result in detectable quantities at IMP outfall 103 for the following reason: The maximum dimethylamine concentration in the steam generators is 10 ppm during layup. The capacity ofeach unit's four steam generators is approximately 80,000 gallons. Steam generators can be drained down at a rate of 400 gpm. Both units' steam generators are not drained down simultaneously.

Therefore, the maximum concentration of dimethylamine at IMP outfall 103 would be 0.007 ppm. The MDL for dimethylamine is 0.1 ppm) VI. POTENTIAL DISCHARGES NOT COVERED BY ANALYSIS Is any pollutant listed in Item V-C a substance or a component of a substance which you currently use or manufacture as an intermediate or final product or byproduct? 1[] YES (list all such polltants belo, ) 10 NO (go to Item VJ-B) n.m. I EPA Form 3510-2C (8-90) PAGE 3 of 4 CONTINUE ON REVERSE

CONTINUED FROM THE FRONT VII. BIOLOGICAL TOXICITY TESTING DATA Do you have any knowledge or reason to believe that any biological test for acute or chronic toxicity has been made on any of your discharges or on a receiving water in

 &ion to your discharge within the last 3 years?

E] YES (identify the test(s) and describe their purposes below) NO (go to Section VIII) VIII. CONTRACT ANALYSIS INFORMATION Were any of the analyses reported in Item V performed by a contract laboratory or consulting firm? 0 YES (list the name, address, and telephone number of andpollutantsanalyzed by, [] NO (go to Section 1') each such laboratoryorfirm below) C. TELEPHONE D. POLLUTANTS.ANALYZED A(area code & no.) (list) Environmental Science Corp. 12065 Lebanon Road (615)758-5858 All except total residual Mt. Juliet, TN 37122 (800)767-5859 chlorine, pH, and sulfite IX CERTIFICATION I ceruly under penaty ol taw that[ itis documentn and l atitacnments were prepared underf my dullcuon o u!*.pefi-tlun it, accofuance wit"I a1 systemr designed to assure hlat qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief,, true, accurate, and complete. I am aware that there are significantpenalties for submitting false information, including the possibility of fine and imprisonment for knowing violations. A. NAME & OFFICIAL TITLE (type orprint) B. PHONE NO. (area code & no.) Timothy P. Cleary, Site Vice President, Sequoyah Nuclear Plant (423) 843-7001 I IGNATURE D. DATE SIGNED I EPA Form 3510-2C (N-90) .PAGE 4 of 4

PLEASE FRI TYPE IN THE UNSHADED AREAS ONLY. You may report some or all of this information UMBER (copy from Item I of Form 1) on se (use the same format) instead of completing these pages. NME SEE INSTRU TIONS. TN56400205044 IUTFALL NO. V. INTAKE AND EFFLUENT CHARACTERISTICS (continued from page 3 of Form 2-C) 103 PART A -You must provide the results of at least one analysis for every pollutant in this table. Complete one table for each outfall. See instructions for additional details.

3. UNITS 4. INTAKE

2. EFFLUENT (specify i/blank) .(optional)

b. MAXIMUM 30 DAY VALUE c. LONG TERM AVRG. VALUE a. LONG TERM

a. MAXIMUM DAILY I* VALUE l (iiavailable) (i/available)

(1) (1) d NO .OF a. CONCEN- AVERAGE (1) VALUE b.NOI OF

1. POLLUTANT CONCENTRATION (2) MASS CONCENTRATION (2)MASS (1) CONCENTRATION (2) MASS ANALYSES TRATION b. MASS CONCENTRATION (2) MASS ANALYSES

a. Biochemical Oxygen 5 Demand (BOD) <5. 0., 1 mg/L

b. Chemical Oxygen Demand (COD) <20 1 rg/L

c. Total Organic Carbon (TOC) 3.6 1 mg/L Fd. Total Suspended Solids (TSS) 16 16.1 8.9 77 mg/L

e. Ammonia (asN) <0 .10 1 mg/L VALUE VALUE VALUE VALUE

f. Flow 1.237 1.549 1.191 367 MGD

g. Temperature VALUE VALUE VALUE VALUE (Winter) N/A N/A N/A

h. Temperature VALUE VALUE VALUE VALUE (summer) 31 . 7 N/A N/A 1 C MINIMUM MAXIMUM MINIMUM MAXIMUM ,,N

i. pH 6.45 8.96 N/A N/A . : 179 STANDARD UNITS PART B - Mark "X" in column 2-a for each pollutant you know or have reason to believe is present. Mark "X" in column 2-b for each pollutant you believe to be absent. If you mark column 2a for any pollutant which is limited either directly, or indirectly but expressly, in an effluent limitations guideline, you must provide the results of at least one analysis for that pollutant. For other pollutants for which you mark column 2a, you must provide quantitative data or an explanation of their presence in your discharge. Complete one table for each outfall. See the instructions for additional details and requirements.

2. MARK "X" "3. EFFLUENT 4. UNITS 5. INTAKE (optional)

1. POLLUTANT b. MAXIMUM 30 DAY VALUE c. LONG TERM AVRG. VALUE a. LONG TERM AVERAGE AND a. b. a. MAXIMUM DAILY VALUE (ifavailable) (ifavailable) VALUE CAS NO. BELIEVED BELIEVED (1) 1) (1) d. NO. OF a. C1NCEN- (1) .10. OF (if available) , PRESENT ABSENT CONCENTRATION . .(2) MASS CONCENTRATION (2) MASS CONCENTRATION (2) MASS ANALYSES TRATION b. MASS CONCENTRATION (2) MASS ANALYSES

a. Bromide (24959-67-9) <1.0 1 mg/L

b. Chlorine, Total Residual <0 . 05 1 mg/L

c. Color X 3.0 1 PCU

d. Fecal Coliform <332 1 /100ML

e. Fluoride (16984-48-8) <0.10

                                                      <                                                                                                             1              mg/L I. Nitrate-Nitrite (as N)                                                <0 . 10                                                                   "1                                                 mg/L EPA Form 3510-2C (8-90)                                                                                                       PAGE V-1                                                                                           CONTINUE ON REVERSE

ITEM V-B CA klWUED FROM FRONT

2. MARK "X" 3. EFFLUENT 4. UNITS 5. INTAKE (oW

1. POLLUTANT . b. MAXIMUM 30 DAY VALUE c. LONG TERM AVRG. VALUE a. LONG TERM AND a. b. a. MAXIMUM DAILY VALUE (ifavailable) (ifavailable) AVERAGE VALUE CAS NO. BELIEVED BELIEVED (1) d(1)

d. NO. OF a. CONCEN- (1I b NO. OF (ifavailable) PRESENT ABSENT CONCENTRATION (2) MASS CONCENTRATION (2) MASS CONCENTRATION (2) MASS ANALYSES TRATION b. MASS CONCENTRATION (2) MASS ANALYSES

g. Nitrogen, Total Organic (w - $.7 1 mg/L N) _

h. Oil and Grease <5.0 <6. <5.6 81 mg/L Phosphorus (as P), Total 0.14 1 mg/L (7723-14-0) 1

j. Radioactivity

1) Alpha, Total X <5 .83 1 pCi/L (2) Beta, Total X 3.22 1 pCi/L (3) Radium, TotalI (4) Radium 226, Total x__ __ _ _

k. (as Sulfate SQ,( X .74 .

1 mag/ L (14808-79-8) I. Sulfide (asS) <0. 050 1 mg/L

m. Sulfite (asSO,) X 2.5 1 rftg/L (14265-4 5-3) " "

n. Surfactants X 0.20 1 mg/L

o. Aluminum, (7429-90-5)

Total x 0.52 1 mg/L

p. Barium, Total X (7440-39-3) 0.03 5 1 mg/L

q. Boron, Total (744042-8) <0.20 I mg/L

r. Cobalt, Total (7440-48-4) <0. 0010 1 mg/L

s. Iron, Total (7439_89.6) 0. 19 1 mg/L

t. Magnesium, Total (7439-95-4) X 5. 9 1 mg/L

u. Molybdenum, Total X1 m/ ___

(7439-98-7) <0.0050 1_mg/_._L

v. Manganese, Total (7439-96-5) 0.4 8 1 mg/L

w. Tin, Total (7440-31-5) < 0.0010 1 mg/L

x. Titanium, Total 1 mg/L (7440-32-6) - <0.A01N0 EPA Form 3510-2C (8-90)

PA.GE V-2 CONTINUE ON PAGE V-3

EPA ID. NUMBER (copy from temnI of Form 1) OUTFALL NUMBER CONTINUED FROM PAGE 3 OF. FORM 2-C TNS640020504 103 PART C - If you are a primary industry and this outfall contains process wastewater, refer to Table 2c-2 in the instructions to determine which of the GC/MS fractions you must test for. Mark "X" in column 2-a for all such GC/MS fractions that apply to your industry and for ALL toxic metals, cyanides, and total phenols. If you are not required to mark column 2-a (secondary industfies, nonprocess wastewater outfalls, and nonrequired GC/MS fractions), mark "X" in column 2-b for each pollutant you know or have reason to believe is present. Mark "X" in column 2-c for each pollutant you believe is absent. If you mark column 2a for any pollutant, you must provide the results of at least one analysis for that pollutant. If you mark column 2b for any pollutant, you must provide the results of at least one analysis for that pollutant if you know or have reason to believe it will be discharged in concentrations of 10 ppb or greater. If you mark column 2b for acrolein, acrylonitrle, 2,4 dinitrophenol, or 2-methyl-4, 6 dinitrophenol, you must provide the results of at least one analysis for each of these pollutants which you know or have reason to believe that you discharge in concentrations of 100 ppb or greater. Otherwise, for pollutants for which you mark column 2b, you must either submit at least one analysis or briefly describe the reasons the pollutant is expected to be discharged. Note that there are 7 pages to this part; please review each carefully. Complete one table'(all 7 pages) for each outfall. See instructions for additional details and requirements.

2. MARK "X" 3. EFFLUENT 4. UNITS S. INTAKE (optionail)

1. POLLUTANT b, MAXIMUM 30 DAY VALUE c. LONG TERM AVRG. a. LONG TERM AND a. b. c. a. MAXIMUM DAILY VALUE (if aailable) VALUE (ifavailable) AVERAGE VALUE CAS NUMBER TESTING BELIEVED BELIEVED d. NO. OF a. CONCEN- b. NO. OF (if available) REQUIRED PRESENT ABSENT CONCENTRATION (2) MASS CONCENTRATION (2) MASS CONCENTRATION (2)MASS ANALYSES TRATION b. MASS CONCENTRATIO 2MAS NALYSES METALS, CYANIDE, AND TOTAL PHENOLS 1M. Antimony, Total (7440-36-0) . <0.0010 1 mg/L 2M. Arsenic, Total (7440-38-2) .X\ <0.0010 1 mg/L 3M. Beryllium, Total (7440-41-7) X <0.0010 11 g/L 4M. Cadmium, Total (7440-439) <0.00050 1 mg/L 5M. Chromium, 1 mg/L Total (7440-47-3) /<0 .0 010 6M. Copper, Total X 1 mg/L (7440-50-8) . 0X0045g 7M. Lead, Total (7439-92-1) X <0 0 0 10 1 1./ rg/L 8M. Mercury, Total 1 (7439-97-6) X <0 0002 1g/L 9M. Nickel, Total 0 1 rag / L (7440-02-0) . 0 .0 016 10M. Selenium, Total (778249-2) X <0 . 0010 0g/L 1

11M. Silver, Total (7440-22-4) X <0.00050 1 mg/L 12M. Thallium, Total (7440-28-0) -< 0.010 1 g/L 13M. Zinc, Total (7440-66-6) <0.010 1 mg/L 14M. Cyanide, 1_ Total (57-12-5) <0.0050 1 rg/L 15M. Total Phenols, X<0040 X < a/ mg/L DIOXIN 2,3,7,8-Tetra- DESCRIBE RESULTS chlorodibenzo-P-Dioxin (1764-01-6) EPA Form 3510-2C (8-90) PAGE V-3 CONTINUE ON REVERSE

MMNUE THE FRONT _________ 2 MARK X" 3. EFFLUENT 4. UNITS 5, INTAKE

1. POLLUTANT b MAXIMUM 30 DAY VALUE c. LONG TERM AVRG. a. LONG TERM AND a. b. c. a. MAXIMUM DAILY VALUE (ifavailable) VALUE (ifavailable) AVERAGE VALUE CAS NUMBER TESTING BELIEVED BELIEVED (1) I 1 1 d. NO. OF a CONCEN- (1) b NO OF TESTING~~N BEIVEBLEVDAALSS(RTO (ifavailabe) REQUIRED PRESENT ABSENT

                                             ... CONCENTRATION          (2) MASS CONCE     N 2)      (2)MASS   CONCERATION              ANALYSES     TRATION       b MASS

b. AS CONCENTRATON OCETAIOA2 MASS MS ANALYSES NAYE GC/MS FRACTION - VOLATILE COMPOUNDS 1V. Accrolein (107-02-8) <O.05/

2V. Acrylonitrile (107.13-1) X <0. 010 1 mg/L 3V. Benzene (71-43-2) <0.0010 1 mg/L 4V. Bis (Chloro-methyl) Ether (542-88-1) x 5V. Bromoform (75-25-2) <0.0010 "1 mg/L 6V. Carbon Tetrachloride <0 .0010 1. mg/L (56-23-5) x 7V. Chlorobenzene < (108-90-7) <0. 0010 1 8V. Chlorodi- - bromomethane <0 0 0 10 1 mg/L (124-48-1) __ 9V. Chloroethane < (75-00-3) < 0.0050 - 1 ag/L 10V. 2-Chloro-ethylvinyl Ether <0 . 05 0 1 mg/L (110-75-8) x 11V. Chloroform (67-66-3) <0. 0050 1 mg/L 12V. Dichloro-bromomethane <0.0010 1 mg/L (75-27-4) <0. 0010]1 mg/L 13V. Dichloro-difluoromethane X <0 . 0050 (75-71-8)"- 1 Mg/L 14V. 1,1-Dichloro- 0 ethane (75-34-3) _<_0._0_0_t_0 I mg_/_L 15V. 1,2-Dichloro- < ethane (107-06-2) <0.0010 1 "mg /L 16V. 1,1-Dichloro- \0 0/ 10 mg/L ethylene (75-35-4) x<0. Ol 1 _/ 17V. 1,2-Dichloro- " < propane (78-87-5) x < 0 .0 0 1_0 1 Mg/L 18V. 1,3-Dichloro-propylene <X0. 0010 1 mg/L (542-75-6) X 19V. Ethylbenzene (100-41-4) <0 . 0010

                                                       <0x001                                                                                    1        mg/L m/

20V. Methyl 01 mg/ Bromide (74-83-9) /< .0050 l mg/L 21V. Methyl mg/L Chloride (74-87-3) <0 0 02 5 EPA Form 3510-2C (8-90) PAGE V-4 CONTINUE ON PAGE V-5

GC/MS FRACTION - VOLATILE COMPOUNDS (continued) 22V. Methylene Chloride (75-09-2) I <

                                           <0 . 0050 23V. 1,1,2;2-Tetrachloroethane                           <0     0010 (79-34-5)               x                                                                    mg/L 24V. Tetrachloro-                            <

ethylene (127-18-4)/<0.0010 1 mg/L 25V. Toluene 1 mg/L (108-88-3) <0.0050. 26V. 1,2-Trans-Dichloroethylene <00 .0010 1 mg/L (156-60-5) 27V. 1,1,1-Trichloro- X ethane (71-55-6) <0 . 0010 1 mg/L 28V. 1,1,2-Trichloro- < ethane (79-00-5) < 0.0010 1 mg/L 29V Trichloro-ethylene (79-01-6) x < 0 . 0 010 1 mg/L 30V. Tdchloro-fluoromethane 0.0050 mg/L (75-694) x < 50 _.0 mg/ L 31V. Vinyl Chloride < (75-01-A) <0. 0010 1mg/L GC/MS FRACTION - ACID COMPOUNDS 1A. 2-Chlorophenol X<0 .010 1 Mg/L (95-57-8) < 0.0 1 0 l _ g/ L 2A. 2,4-Dichloro- 0 0 phenol (120-83-2) < .010 1 mg/L 3A. 2,4-Dimethyl- <0.010 1 phenol (105-67-9) <_O_.__0 1 _0_1__g/_L 4A. 4,6-Dinitro-O- <0.010 1 mg/L Cresol (534-52-1) < 5A. 2,4-Dinitro- 0 phenol (51-28-5) <0 . 0 10 1 / 6A. 2-Nitrophenol <0 010 1 (88-75-5) < 0.0<_0_____/_ 7A. 4-Nitrophenol <0 . 0 10 1 (100-02-7) mg/L 8A. P-Chloro-M- 0 Cresol (59-50-7) <0 . 010 1 9A. Pentachloro- 0m L phenol (87-86-5) <0.. 010 1 10A. Phenol (108-95-2) , <0 . 010 1 mg/L 1IA. 2,4,6-Trichloro-phenol (88-05-2) 0

                                            < 0 . 0  10T                             1      mg/L EPA Form 3510-2C (8-90)

PAGE V-5 CONTINUE ON REVERSE

C NU THE FRONT _____

2. MARK X 3. EFFLUENT

1. POLLUTANT 4. UNITS 5. INTAKE(

AND a. b. b. MAXIMUM 30 DAY VALUE :c. LONG TERM AVRG.

c. a. MAXIMUM DAILY VALUE (iJfavailable) VALUE (ifavailable) -a. LONG TERM.

CAS NUMBER TESTING BELIEVED AVERAGE VALUE BELIEVED

d. NO. OF a. CONCEN- b. NO. OF (iCavailable) REQUIRED PRESENT ABSENT CONCENTRATION (2)MASS CONCENTRATION (2)MASS CONCENTRATION (2)MASS ANALYSES TRATION b. MASS CONCENTRATIONJ (2)MASS ANALYSES GC/MS FRACTION - BASE/NEUTRAL COMPOUNDS 1B. Acenaphthene (83-32-9) X x< 0 .0 010 1mg/L.

2B. Acenaphtylene (208-96-8) X <_0.0_0_ __0_1 mg/L

36. Anthracene <0.0010 (120-12-7) mg/L

                                                               <0. 0010     *

46. Benzidine 1 mg/L (92-87-5) X <0.052 mg/L 5B. Benzo (a)

Anthracene ,(56-55-3) mg/L I<0.0010

66. Benzo (a) 1 mg/L Pyrene (50-32-8) / . __<0.0010_1__

__/L

76. 3,4-Benzo-fluoranthene x <0.0010 mg/L (205-99-2).

8B. Benzo (ghi) Perylene(191-24-2) x - <0.0010 1 _ng/L 96.Benzo (k). Fluoranthene

                                                              <0.0010 (207-08-9)                                                    <0.0010                                                                                  1         mg/L.

10B. Bis (2-Chloro-elhoxy) Methane N <0.010 1 Mg/L (111-91-1) ,x. 2 116. Bis ( -Chloro-ethyl) Ether <0 . 010 (111-44-) Ether 1 mg/L 12B. Bis (2-Chloroisopropyl) 00 1 mg/L Ether (102-80-1 ) x<0.010 136. Bis (2-Ethyl-hexyl) Phthalate <0.00101 (117-81.7) mg/L

                                                              <0 ,I0010
                                                                                                                                                       !         mg/L 146. 4-Bromophenyl Phenyl Ether                                                     0.010 (101-55-3)              x1                .                    <g/L                                                                                              mg/L 1

15B. Butyl Benzyl < 0 .0011g/L Phthalate (85-68-7) < 0 16B. 2-Chloro-naphthalene (91-58-7) <<0. 010 1mg/L 17B. 4-Chloro-phenyl Phenyl Ether <0.01 0 (7005.72-3) 1 g/ 188. Chrysene (218-01-9) <0.0010

                                               ..                   .                                                                                            mg/L a/                                           I 19B. Dibenzo (a,h)

Anthracene (53-70-3) < 0. 0 0 1 0 i mg/L - 20B. 1,2-Dichloro- < .00010 benzene (95-50-1) 1

                                                              <0 . 00 10 1         mg/ L 216. 1,3-Di-chloro-benzene(541-73-1) (                                            <0.0010                                               -               J                            mg/L EPA Form 3510-2C (8-90)                                                                                        PAGE V-6                                                                             CONTINUE ON PAGE V-7

CONTINUFAA9MON& PAGE V-6 2ý MARK "X" 3. EFFLUENTW 4. UNITS 5. INTAKE

1. POLLUTANT b, MAXIMUM 30 DAY VALUE c. LONG TERM AVRG. a. LONG TERM AND a. b. c. a. MAXIMUM DAILY VALUE (if available) VALUE (favailable) AVERAGE VALUE CAS NUMBER TESTING BELIEVED BELIEVED (1) (1) (1) d. NO. OF a. CONCEN- (1) 1 bMNO. OF o(f available) REQUIRED PRESENT ABSENT CONCENTRATION (2) (. MASS CONCENTANALYSES TRATION MASS CONCENTRATION (2) MAS ANALYSES GC/MS FRACTION - BASE/NEUTRAL COMPOUNDS (continued) 22B. 1,4-Dichloro-benzene (106-46-7) x < 0 . O0 1.0 1 mg/L 23B. 3,3-Dichloro- 0 benzidine (91-94-1) <0 .010 1 mg/L 248. Diethyl 0 Phthalate (84-66-2) < 0. 0010 1 mg/L 256. Dimethyl Phthalate <0.0010 1 (131 3) <0. 0 0 _m /

26B. Di-N-Butyl < Phthalate (84-74-2) <0.0010 1 mg/L 27B. 2,4-Dinitro-toluene (121-14-2) <0 . 0 10 1 mg/L 28B. 2,6-Dinitro- 0 toluene (606-20-2) <0 .010 1 mg/L 29B. Di-N-Octyl Phthalate (117-84-0) < 0 . 0 0 10 1 mg/L 30B. 1,2-Diphenyl-hydrazine (as Azo- 00/ 1 benzene) (122-66-7) /, <0 .0 10 31B. Fluoranthene (206-44-0) < 0.0010 1 mg/L 326. Fluorene (86-73-7) . <0.0010 1 mg/L 336. Hexachloro- X benzene (118-74-1) <0.010 1 mg/L 34B. Hexachloro- <0 butadiene (87-68-3) x<0 .010 1 mg/L 35B. Hexachloro-cyclopentadiene <0.010 1 mg/L (77-474) < .0i0 _g_ 366 Hexachloro- <0 ethane (67-72-1) <0 .010 1 mg/L 37B. Indeno " (1,2,3-cd) Pyrene < (193-39-5) <0.0010 1 mg/L 38B. Isophorone 0 1 mg/L (78-59-1) <0. O01 39B. Naphthalene < (91-20-3) <0.0010 1 mg/L 40B. Nitrobenzene 0 (98-95-3) x<0.010 1 mg/L 41B. N-Nitro-sodimethylamine X <0. 52 1 mg/L (62-75-9) x 42B. N-Nitrosodi-N-Propylamine <0 . 010 mg/L (621-64-7) x I I EPA Form 3510-2C (8-90) PAGE V-7 CONTINUE ON REVERSE

£2T2L4M THE "FRONT "X" 3. FFARK A. 4. UNITS IN AKýW

5. INTAKE 1 1.POLLUTANT b MAXIMUM 30 DAY VALUE C.LONG TERM AVRG. a. LONG TERM AND a. b. c. a. MAXIMUM DAILY VALUE (ifavailable) VALUE (ifavailable) AVERAGE VALUE CAS NUMBER (if available)

TESTING BELIEVED BELIEVED (1) (1)(2M(1) d NO, OF a. CONCEN- (1) b. NO. OF REQUIRED PRESENT ABSENT CONCENTRATION (2) MASS CONCENTRATION (2) MASS CONCENTRATION (2) MASS. ANALYSES TRATION b. MASS CONCENTRATION (2) MASS ANALYSES GC/MS FRACTION - BASE/NEUTRAL COMPOUNDS (continued) 43B. N-Nitro-sodiphenylamine (86-30-6) X <00.010 l 11 m/ mg/L 44B. Phenanthrene (85-01-8) <0.0010 1 mg/L 45B. Pyrene (129-00-0) <0. 0010 1 mg/L 46B. 1,2,4-Tri-chlorobenzene 0 (120-82-1) __0.0 10_1_rag/L GC/MS FRACTION - PESTICIDES 1P. Aldrin (309-00-2) 2P. a-BHC (319-84-6) X 3P. P-BHC (319-85-7) x 4P. y-BHC (58-89-9) X 5P. 5-BHCIC (319-86-8) 6P. Chlordane X (57-74-9) x 7P. 4,4'-DDT (50-29-3) x 8P. 4,4'-DDE (72-55-9) x 9P. 4,4'-DDD (72-54-8) x 10P. Dieldrin (60-57-1) x 11P. a-Enosulfan (115-29-7) x 12P. P-Endosuifan (115-29-7) X 13P. Endosulfan Sulfate (1031-07-8) x 14P. Endrin (72-20-8) 15P. Endrin Aldehyde (7421-93-4) x 16P. Heptachlor (76-44-8) x EPA Form 3510-2C (8-90) PAGE V-8 CONTINUE ON PAGE V-9

EPA I.D. NUMBER (copyfrom Item I ofForm I) UTFALL NUMBER TN5640020504 103 CONTINUED FROM PACE V-B

2. MARK "X" 3. EFFLUENT 4. UNITS 5. INTAKE (optional)

1. POLLUTANT b. MAXIMUM 30 DAY VALUE c. LONG TERM AVRG. a. LONG TERM ANa. b. c. a. MAXIMUM DAILY VALUE (ifavailable) VALUE (i[available)

CAS NUMBER AVERAGE VALUE TESTING BELIEVED BELIEVED d. NO. OF a. CONCEN- (1) b. NO. OF (i[available) REQUIRED PRESENT ABSENT CONCENTRATION (2) MASS CONCENTRATION (2) MASS CONCENTRATIONT(2) MASS ANALYSES TRATION b. MASS CONCENTRATION (2) MASS ANALYSES GC/MS FRACTION - PESTICIDES (continued) 17P. Heptachlor Epoxide (1024-57-3) 18P. PCB-1242 < (53469-21-9) <0 0052 1 mg/L 19P. PCB-1254 (11097-69-1) x <0. 0052 1 mg/L 20P. PCB-1221 (11104-28-2) <0. 0052 1 mg/L 21P. PCB-1232 (11141-16-5) X <0.0052 1 mg/L 22P. PCB-1248 (12672-29-6) , <0.0052 1 mg/L 23P. PCB-1260 (11096-82-5) _<0.0052 1 mg/L 24P. PCB-1016 (12674-11-2) <0.0052 1 mg/L -. 25P. Toxaphene (8001-35-2) ___. EPA Form 3510-2C (8-90) PAGE V-9

EPA I.D. NUMBER (copy froz Item I ofFo-,m ) Form Approved. OMB No. 2040-0086. Please print or type in the unshaded areas only. TN5 64 0020 504I Approval expires 3-31-98. Id ORCMP NPDES C E PAEXISTING APPLICATION FOR PERMIT TOPROTECTION U.S. ENVIRONMENTIAL WASTEWVATER DISCHARGE AGENCY MANUFACTURING, COMMERCIAL, MINING AND SILVICULTURE OPERATIONS ConsolidatedPermits Program

1. OUTFALL LOCATION For each outfall, list the latitude and longitude of its location to the nearest 15 seconds and the name of the receiving water:

A. OUTFALL NUMBER B. LATITUDE C. LONGITUDE (list) 1.1DEG. 2. MIN. 3. SEC. . 1.DE0 . 2. MIN. 3.SEC. D. RECEIVING WATER (name) 107 IMP 35.00 8.00 24.00 85.00 8.00 3.00 Low Volume Waste Treatment Pond II. FLOWS, SOURCES OF POLLUTION, AND TREATMENT TECHNOLOGIES A. Attach a line drawing showing the water flow through the facility. Indicate sources of intake water, operations contributing wastewater to the effluent, and treatment units labeled to correspond to the more detailed descnptions in Item B. Construct a water balance on the line drawing by showing average flows between intakes, operbtions, treatment units, and outfalls. If a water balance cannot be determined (e.g., for certain mining activities), provide a pictorial description of the nature and amount of any sources of water and any collection or treatment measures. B. For each outfall, provide a description of: (1) All operations contributing wastewater to the effluent, including process wastewater, sanitary wastewater, cooling water, and storm water runoff; (2) The average flow contributed by each operation; and (3) The treatment received by the wastewater. Continue on additional sheets if

1. OUT- 2. OPERATION(S) CONTRIBUTING FLOW 3. TREATMENT FALL b. AVERAGE FLOW b. LIST CODES FROM NO. (list) a. OPERATION (list) (include units) . a. DESCRIPTION TABLE 2C-1 Discharges include drainage from: 0.0022 MOD Sedimentation (settling) 107 Neutralization 2 K IMP Chemical Precipitation chemical Oxidation 5

                                              .2 Slow Sand Filtration V

Metal Cleaning Waste Floculation (0.0000-- MOD) 1 O Storm water runoff (0.0012 MGD) Precipitation minus evaporation (0.0010 Moo)

             -- Flow is   0 gal/year (0.0000 MCD)

NOTE: The metal cleaning waste pond Outfall 107 was not sampled during the 24-hour event due to the fact that it is an internal monitoring _ oint and was not discharging during the monitoring event. FIOIAL USE ONLY (effluent guidelines sub-cotegories) EPA Form 3510-2C (8-90) PAGE 1 of 4 CONTINUE ON REVERSE

CONTINUED FROM THE FRONT C. Except for storm runoff, leaks, or spills, are any of the discharges described in Items Il-A or B intermittent or seasonal? 1] YES (complete the following table) - L1 NO (go to Sýection 111)

3. FREQUENCY 4. FLOW I 2. OPERATION(s) *

a. DAYS PER WEEK b. MONTHS a. FLOW RATE (inmgd B. TOTAL VOLUME (gde) with -its)

1. OUTFALL CONTRIBUTING FLOW ((l) PER YEAR 1. LONG TERM 2. MAXIMUM 1. LONG TERM 2. MAXIMUM C. DURATION NUMBER (h(t) .list) .oerage) (sw5 verage) AVERAGE DAILY AVERAGE DAILY ( days) 107 IMP . Metal Cleaning waste as necessary; Frequency various plant systems.are cleaned/ and flushed using any of the following:. duration sulfuric acid, phosphate cleanings, of cleanings caustic, sodium hypochlorite, sodium acid, hydrazine, determined bromide, citric hydrogen peroxide, EDTA,. Metal dimethylamine,._ammonium hydroxide, cleaning nitric acid, hydrochloric acid, wastes are hydrofluoric acid, EDA, phosphoric infrequenC acid, and corrosion inhibitors. NOTE: ly The metal cleaning waste pond has not tO the ponds.

discharged since 5/31/2006. ponds Ill. PRODUCTION- --- - - A. Does an effluent guideline limitation promulgated by EPA under Section 304 of the Clean Water Act apply to your facility? 71 YES (complete Item 111-8) [] NO (go to Section It) B. Are the limitations in the applicable effluent guideline expressed in terms of production (or other measure of opertion)? [] YES (complete term IlI-C) . I[7] NO (go to Section It) C. If you answered "yes" to Item Il-B, list the quantity which represents an actual measurement of your level of production, expressed in the terms and units used in the applicable effluent guideline, and indicate the affected outfalls.

1. AVERAGE DAILY PRODUCTION 2 AFFECTED OUTFALLS

a. QUANTITY PER DAY b. UNITS OF MEASURE c. OPERAT(ON, PRODUCT, MATERIAL, ETC. (list outfall numbers) 4 IVOVEMENTS-A. Are you now required by any Federal, State or local authority to meet any implementation schedule for the construction, upgrading or operations of wastewater treatment equipment or practices or any other environmental programs which may affect the discharges described in this application? This includes, but is not limited to, permit conditions, administrative or enforcement orders, enforcement compliance schedule letters, stipulations, court orders, and grant or loan conditions.

U YES (complete the followoing table) [7 NO (go to Item IV-B)

1. IDENTIFICATION OF CONDITION, 2 AFFECTED OUTFALLS 4, FINAL COMPLIANCE DATE

3. BRIEF DESCRIPTION OF PROJECT AGREEMENT, ETC.

a. NO. b: SOURCEOF DISCHARGE a. REQUIRED b. PROJECTED 4 OPTIONAL: You may attach additional sheets describing any additional water pollution control programs (or other environmental projects which may affect your discharges) you now have underway or which you plan. Indicate whether each program is now underway or planned, and indicate your actual or planned schedules for construction.

U MARK "X" IF DESCRIPTION OF ADDITIONAL CONTROL PROGRAMS IS ATTACHED EPA Form 3510-2C (8-90) PAGE 2 of 4 CONTINUE ON PAGE 3

EPA ID. NUMBER (copyfron hem I of Form 1) CONTINUED FROM PAGE 2 I TN5640020504 V. INTAKE AND EFFLUENT CHARACTERISTICS d B, & C: See instructions before proceeding - Complete one set of tables for each outfall - Annotate the outfall number in the space provided. NOTE: Tables V-A, V-B and V-C are included on separate sheets numbered V-1 through V-9. FD. Use the space below to list any of the pollutants listed in Table 2c-3 of the instructions, which you know or have reason to believe is discharged or may be discharged from any outfall. For every pollutant you list. briefly descnbe the reasons you believe it to~be oresent and redori any analytical data in your possession,

1. POLLUTANT 2. SOURCE 1. POLLUTANT 2. SOURCE VI. POTENTIAL DISCHARGES NOT COVERED BY ANALYSIS Is any pollutant listed in Item V-C a substance or a component of a substance which you currently use or manufacture as an intermediate or final product or byproduct?

El YES (list all such pollutantsbelow ) [0 NO (go to Item VI-B) p I PAGE 3 of4 CONTINUE ON REVERSE EPA Form 3510-2C EPA Form (8-90) 3510-2C (8-90) PAGE 3 of 4 CONTINUE ON REVERSE

CONTINUED FROM THE FRONT VII. BIOLOGICAL TOXICITY TESTING DATA Do you have any knowledge or reason to believe that any biological test for acute or chronic toxicity has been made on any of your discharges or on a receiving water in relation to your discharge within the last 3 years?

&              1111 YES (identiyý the test(s) and describe their purposes below)                                     71NO (go to Section P7Lh1) w VIII. CONTRACT ANALYSIS INFORMATION Were any of the analyses reported in Item V performed by a contract laboratory or consulting firm?

[]YES (list the name, address, andtelephonenumber of andpollutants analyzed by, NO (go to Section LX) each such laboratory orfirm below) 4 A. NAME___________C. A.NAME B.ADDRESS TELEPHONE (area code & no.) D. POLLUTANTS ANALYZED (list) IX. CERTIFICATION I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based. on my inquiry of the person or persons who manage the system or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, -including the possibility of fine and imprisonment for knowing violations. A. NAME & OFFICIAL TITLE (type orprint) B. PHONE NO. (area code & no.) Timothy P. Cleary, Site Vice President, Sequoyah Nuclear Plant (423) 843-7001 D. DATE SIGNED I r NAUR PAGE 4 of4

                                                                                                              -2. AA- cA-t EPA Fort,,   3510-~C (8-90)

Form 3510VC PAGE 4 of 4 (8-90) r

EPA ID. NUMBER (copyfrom Item lofForm]) Form Approved. OMB No. 2040-0086. Please print or type in the unshaded areas only. TN5640020504 Approval expires 3-31-98. FORM 'U.S. ENVIRONMENTAL PROTECTION AGENCY 4 2C 2C I80EP EPAPCATION EXISTING MANUFACTURING, FOR PERMIT TO DISCHARGE WASTEWATER COMMERCIAL, MINING AND SILVICULTURE OPERATIONS NPDES ConsolidatedPermits Program

1. OUTFALL LOCTO For each outfall, list the latitude and longitude of its location to the nearest 15 seconds and the name of the receiving water.

A. OUTFALL NUMBER B. LATITUDE C. LONGITUDE (list) 1. DEG. 2. MIN. 3. SEC. 1. DEG. 2. MIN. 3. SEC. D. RECEIVING WATER (name) 110 35.00 13.00 23.00 85.00 *5.00 9.00 Intake Forebay II. FLOWS, SOURCES OF POLLUTION, AND TREATMENT TECHNOLOGIES M A. Attach a line drawing showing the water flow through the facility. Indicate sources of intake water, operations contributing wastewater to the effluent, and treatment units labeled to correspond to the more detailed descriptions in Item B. Construct a water balance on the line drawing by showing average flows between intakes, operations, treatment units, and outfalls. If a water balance cannot be determined (e.g., for certain mining activities), provide a pictorial description of the nature and amount of any sources of water and any collection or treatment measures. B. For each outfall, provide a description of: (1) All operations contributing wastewater to the effluent, including process wastewater, sanitary wastewater, cooling water, and storm water runoff; (2) The average flow contributed by each operation; and (3) The treatment received by the wastewater. Continue on additional sheets if necessary.

1. OUT- 2. OPERATION(S) CONTRIBUTING FLOW 3. TREATMENT FALL b. AVERAGE FLOW b. LIST CODES FROM NO. (list) a. OPERATION (liw) (include units) a. DESCRIPTION TABLE 2C-1 Discharges,include1487.4276 MOD Discharge to Surface Waters A 110 ERCW system Disinfection (other)

(40,3060 MOD) 2 H Cooling towers (closed mode) (14470140 MOD Liquid radwaste treatment. system (0.0501 MGD) Exchange Eon 2 Multimedia Filtration I Q Storm water runoff 10.0528 M4001 Precipitation minus evaporatiorn 10.0048 MOD0 (Recycled cooling water during

             -rma       m-H. is  drsrharedh      t. ro..ugh outfall      110.      Outfall     110 has been I... rive      f"r   14 years         l   remains                                                                                                               _""

in the event the plant goes ino closed mode.) Doutfall 110 was not sampled during the 24-hour samsling event because it is currently inactive. Therefore. there are no analytical results for this outfall. FICIAL USE ONLY (effluent guidelies sub-categories) EPA Form 3510-2C (8-90) PAGE 1 of 4 CONTINUE ON REVERSE

CONTINUED FROM THE FRONT C. Except for storm runoff, leaks, or spills, are any of the discharges deschbed in Items 11-Aor B intermittent or seasonal? 17 YES (complete tbe followmi table)

                                                      ,g                                                []NO (go to Section Ill) 3 FREQUENCY                                                       4. FLOW
.                                        2.OPERATION~s)           .

a. DAYS PER W EEK b. MONTHS a. PLOW RATE ( nm ild)

B. TOTAL VOLUME t u its) ( (specifyi

1. OUTFALL CONTRIBUTING FLOW (sp

                                                                                             . ify         PER YEAR          1. LONG TERM 2. MAXIMUM            1. LONG TERM 2. MAXIMUM           C. DURATION NUM BER (list)                              (list)                                     aveage)            (spec ave-i age)     AVERAGE             DAILY           AVERAGE            DAILY          (in da     s) 110               Cooling Tower Blowdown Basin (Cooling tower blowdown basin discharges recycled cooling water through outfall          110 while the plant is   in closed mode.             The plant has not entered closed mode for the -last                        14 years.      Therefore, outfall                 110 has remained inactive.                If the plant does go into closed mode the discharge flow through outfall                110 will be.

approximately'1487.4276 MGD.I Ill. PRODUCTION- - A. Does an effluent guideline limitation promulgated by EPA under Section 304 of the Clean Water Act apply to your facility? 17 YES (complete 1temr Ill-B) E] NO (go to Section I1) B. Are the limitations in the applicable effluent guideline expressed in terms of production (orother measure of operation)? El YES (complete Item Il1-C) 07 NO (go to Section IV) C. If you answered "yes" to Item IIl-B, list the quantity which represents an actual measurement of your level of production, expressed in the terms and units used in the applicable effluent guideline, and indicate the affected outfalls.

1. AVERAGE DAILY PRODUCTION 2FFECTED OUTFALLS

a. QUANTITY PER DAY b. UNITS I OF MEASURE . I(specify) c. OPERATION, PRODUCT, MATERIAL, ETC. list outfall numbers)

[ IVIPRVEMENTSI A. Are you now required by any Federal, State'or local authority to meet any implementation schedule for the construction, upgrading or operations of wastewater treatment equipment or practices or any other environmental programs which may affect the discharges described in this application? This includes, but is not limited to, permit conditions, administrative or enforcement orders, enforcement compliance schedule letters, stipulations, court orders, and grant or loan conditions. D ] YES (complete the follo wingtable) " NO (go to Item IV-B)

1. IDENTIFICATION OF CONDITION, 2. AFFECTED OUTFALLS BRIEF DESCRIPTION OF PROJECT 4. FINAL COMPLIANCE DATE AGREEMENT, ETC. a. NO. b. SOURCE OF DISCHARGE' 3 R DPRO a. REQUIRED b. PROJECTED SOPTIONAL: You now discharges)you construction.

mayhave attach additional underway or whichsheets youdescribing any whether plan. Indicate additionaleach water pollution program is nowcontrol programs underway (or other or planned, environmental and indicate your projects actual or which plannedmay affect your schedules for n MARK 'X' IF DESCRIPTION OF ADDITIONAL CONTROL PROGRAMS IS ATTACHED EPA Form 3510-2C (8-90) PAGE 2 of 4 CONTINUE ON PAGE 3

TN5640020504 CONTINUED FROM PAGE 2 INTAKE AND EFFLUENT CHARACTERISTICS II & C: See instructions before proceeding - Complete one set of tables for each outfall - Annotate the outfall number in the space provided. NOTE: Tables V-A, V-B, and V-C are included on separate sheets numbered V-1 through V-9. D. Use the space below to list any of the pollutants listed in Table 2c-3 of the instructions, which you know or have reason to believe is discharged or may be discharged from any outfall. For every pollutant you list. briefly describe the reasons you believe it to be present and report any analytical data in your possession.

1. POLLUTANT 2. SOURCE 1. POLLUTANT 2 SOURCE Dimethylamine Steam Generator Layup (The use of dimethylamine will not result in detectable quantities at outfall 110 for the following reason:

The maximum dimethylamine concentration in the steam generators is 10ppm during layup. The capacity of each unit's four steam generators is approximately 80,000 gallons. Steam generators can be drained down at a rate of 400 gpm. Both units' steam generators are not drained down simultaneously. Therefore, the maximum concentration of dimethylamine at outfall 110 would be 0.007ppm. The MDL for dimethylamine is 0.lppm) VI. POTENTIAL DISCHARGES NOT COVERED BY ANALYSIS Is any pollutant listed in Item V-C a substance or a component of a substance which you currently use or manufacture as an intermediate or final product or byproduct? _. YES (ais, all s.c. pollutants below ) .] NO (go to Item VI-B) I W II PACE 3 of4 CONTINUE ON REVERSE EPA Form EPA (8-go) 35.1 O-2C (8-90) Form 3510-2C PAGE 3 of 4 CONTINUE ON REVERSE

CONTINUED FROM THE FRONT VII BIOLOGICAL TOXICITY TESTING DATA Do you have any knowledge or reason to believe that any biological test for acute or chronic toxicity has been made on any of your discharges or on a receiving water in relation to your discharge within the last 3 years? Ai & El YES (identify the test(s) and describe their purposes below) [-1 NO (go to Section VI11) F VIII. CONTRACT ANALYSIS INFORMATION Were any of the analyses reported in Item V performed by a contract laboratory or consulting firm? [I YES (list the name, address, and telephone nrimber of andpollutantsanalyzed'by, [7 NO (go to Section 1Y) each such laboratory orfirm below) C. TELEPHONE (area code & D. POLLUTANTS ANALYZED no.) (list) IX. CERTIFICATION I certify under penalty of law that this document and all attachments were prepared under my direction or supervisionin accordance with a system designed to assure that qualified personnel property gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system or those persons directly responsiblefor gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submittingfalse information, including the possibility of fine and imprisonmentfor knowing violations. A. NAME & OFFICIAL TITLE (type orprint) B. PHONE NO. (areacode & no.) Timothy P. Cleary, Site Vice President, Sequoyah Nuclear Plant (423) 843-7001

.SIGNATURE                                                                                                . DATE SIGNED I

EPA Form 3510- C (8-90) PAGE 4 of4

EPA I.D. NUMBER (copy from Item 1 of Form 1) Form Approved. OMB No. 2040-0086. Please pnnt or type in the unshaded areas only. TN5640020504 Approval expires 3-31-98. FORM U.S. ENVIRONMENTAL PROTECTION AGENCY 4 tNPDES C1W Wi PAEXISTING APPLtCATION FOR PERMIT TO DISCHARGE WASTEWATER MANUFACTURING, COMMERCIAL, MINING AND SILVICULTURE OPERATIONS ConsolidatedPermits Program

or each outfall, list the latitude and longitude of its location to the nearest 15 seconds and the name of the receiving water.

A. OUTFALL NUMBER IB. LATITUDE C. LONGITUDE (list) 1. DEG. 2. MIN. 3. SEC. 1. DEG. 2. MIN. 3. SEC. D. RECEIVING WATER (natne) 116 35.00 13 .00 33 .00 85.00 5.00 13 .00 Tennessee River II. FLOWS, SOURCES OF POLLUTION, AND TREATMENT TECHNOLOGIES A. Attach a line drawing showing the water flow through the facility. Indicate sources of intake water, operations contributing wastewater to the effluent, and treatment units labeled to correspond to the more detailed descriptions in Item B. Construct a water balance on the line drawing by showing average flows between intakes, operations, treatment units, and outfalls If a water balance cannot be determined (e.g., for certain mining activities), provide a pictorial description of the nature and amount of any sources of water and any collection or treatment measures. B. For each outfall, provide a description of: (1) All operations contributing wastewater to the effluent, including process wastewater, sanitary wastewater, cooling water, and storm water runoff; (2) The average flow contributed by each operation; and (3) The treatment received by the wastewater. Continue on additional sheets if necessary. 1 OUT- 2. OPERATION(S) CONTRIBUTING FLOW 3. TREATMENT FALL b. AVERAGE FLOW b. LIST CODES FROM NO. (lit) a. OPERATION (list) (include units) a. DESCRIPTION TABLE 2C-1 CCW Intake Trash Sluice Discharge to surface water 0.0060 MGD 4 A 116

              'Outfall 116 was not sampled during the 24-hour sampling event because the CCW is not chemically treated, therefore the only water that is backwashed into the Tennessee River is raw river water.        Also, NPDES permit renewal applications for TVA coal-fired plants with similar intakes do not include analytical data for intake screen backwash and this has been acceptable to TDEC.

FICIAL USE ONLY (effluent guidelines sub-categories) EPA Form 3510-2C (8-90) PAGE 1of 4 CONTINUE ON REVERSE

CONTINUED FROM THE FRONT C. Except for storm runoff, leaks, or spills, are any of the discharges described in Items Il-A or B intermittent or seasonal? [j YES (complete thefollowing table) Ej NO (go to Section II1)

3. FREQUENCY 4. FLOW 4 1. OUTFALL NUMBER (list)

2. OPERATION(s)

CONTRIBUTING FLOW (list) a DAYS PER WEEK (specify a erage)

b. MONTHS PER YEAR (specify av rage)

a. FLOW RATE (in mngd)

1. LONG TERM AVERAGE

2. MAXIMUM DAILY B. TOTAL VOLUME (specify with units) 1.LONG TERM 2. MAXIMUM AVERAGE DAILY C. DURATION (in days) 116 CCW Intake Trash Sluice 12 0 .0060 0 .0450 0. 01 Ill. PRODUCTION --

A. Does an effluent guideline limitation promulgated by EPA under Section 304 of the Clean Water Act apply to your facility? W1I YES (complete Item 111-B) -- NO (go to Section IV) B. Are the limitations in the applicable effluent guideline expressed in terms of production (or other measure of operation)? LI YES (complete Item Ill-C) [] NO (go to Section I') C. If you answered "yes" to Item Ill-B, list the quantity which represents an actual measurement of your level of production, expressed in the terms and units used in the applicable effluent guideline, and indicate the affected outfalls.

1. AVERAGE DAILY PRODUCTION 2. AFFECTED OUTFALLS

a. QUANTITY PER DAY b. UNITS OF MEASURE c. OPERATION, PRODUCT, MATERIAL, ETC. (list outfall numbers)

(specify) II A. Are you now required by any F-ederal, lState or local authority to meet any implementation schedule for the construction, upgrading or operations of wastewater treatment equipment or practices or any other environmental programs which may affect the discharges described in this application? This includes, but is not limited to, permit conditions, administrative or enforcement orders, enforcement compliance schedule letters, stipulations, court orders, and grant or loan conditions. E] YES (complete the following table) Z NO (go to'Item IV-B)

1. IDENTIFICATION OF CONDITION, 2. AFFECTED OUTFALLS 4. FINAL COMPLIANCE DATE AGREEMENT, ETC. 3. BRIEF DESCRIPTION OF PROJECT

a. NO. b. SOURCEOF DISCHARGE a. REQUIRED b. PROJECTED Ik ischarges)you now have underway or which you plan Indicate whether each program is now underway or planned, and indicate your actual or planned schedules for u cl ul \IU I L ý TO CU construction.

E m a y a tta c h a d d it illo n a l s rhe e ts d e s c rib in Ig a n y a udli lcaa l w a te r p o allution ic o n~tro l pro g ra m s o to atthe MARK "X" IF DESCRIPTION OF ADDITIONAL CONTROL PROGRAMS IS ATTACHED r e n v iro m ~n rne n ta ttp etsa { w lu nma y a h uc tGyo u r EPA Form 3510-2C (8-90) PAGE 2 of 4 CONTINUE ON PAGE 3

EPA I.D. NUMBER (copy from Iem I of Form I) CONTINUED FROM PAGE 2 I1TN564 002 0 5 04 V. INTAKE AND EFFLUENT CHARACTERISTICS

       & C: See instructions before proceeding - Complete one set of tables for each outfall - Annotate the outfall number in the space provided.

AM. NOTE: Tables V-A, V-B, and V-C are included on separate sheets numbered V-i through V-9. Use the space below to list any of the pollutants listed in Table 2c-3 of the instructions, which-you know or have reason to believe is discharged or may be discharged from onv, ntltf~ll Fn~r*~ nnhlillfint vnrg Itt hritflv,,lovnhc tho rntcnnc V~ni, hc~itvo it tn h~tnrntnt ~nn, rtnnrl nnv mnnlvtir~I rLitm in.vnll nt" ntt*.*n

1. POLLUTANT 2. SOURCE 1. POLLUTANT 2. SOURCE VI POTENTIAL DISCHARGES NOT COVERED BY ANALYSIS Is any pollutant listed in Item V-C a substance or a component of a substance which you currently use or manufacture as an intermediate or final product or byproduct?

I [] YES (list all such pollutants belo' ) [1 NO (go to Item 7-B) 1 EPA Form 3510-2C (8-90) PAGE 3 of 4 CONTINUE ON REVERSE

CONTINUED FROM THE FRONT VII. BIOLOGICAL TOXICITY TESTING DATA Do you have any knowledge or reasonto believe that any biological test for acute or chronic toxicity has been made on any of your discharges or on a receiving water in relation to your discharge within the last 3 years? A1Mb 0i YES (identify the tevt(s) and describe their purposes below) Z NO (go to Section vu7i1 W VIII. CONTRACT ANALYSIS INFORMATION Were any of the analyses reported in Item V performed by a contract laboratory or consulting firm? EYES (list the name, address, and telephone number of andpollutants analyzed by, ] NO (go to Section LX) each such laboratoryorfirm below) k._NAME___________C. I TELEPHONE D. POLLUTANTS ANALYZED A NAME "B. ADDRESS (area code & no.) (list) IX CERTIFICATION I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. lam aware that there. are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations. A. NAME & OFFICIAL TITLE (type orprint) B. PHONE NO. (area code & no.) Timothy P. Cleary, Site Vice President, Sequoyah Nuclear Plant (423) 843-7001 D. DATE SIGNED SIGATREph I ZT7 ,#,Jo,= PAGE 4 ot4 II EPA Form35lO-2d'(8-90) EPA Form 3510-28(8-90) . I PAGE 4 of 4

• EPA I.D. NUMBER (copyfrom Item I of'Form 1) Form Approved.

OMB No. 2040-0086. Please print or type in the unshaded areas only. IITN56400205 04 Approval expires 3-31-98.

      °cOREP~APPLICATION C

U.S. ENVIRONMENTAL FOR PERMIT TOPROTECTION WigWEPAEXISTING MANUFACTURING, COMMERCIAL, MINING AND SILVICULTURE OPERATIONS DISCHARGE AGENCY WASTEWATER NPIDES ConsolidatedPermits Program I. OUTFALL LOCATION For each outfall, list the latitude and longitude of its location to the nearest 15 seconds and the name of the receiving water. A. OUTFALL NUMBER B. LATITUDE C. LONGITUDE (list) 1. DEG [ 2. MIN.[ 3. SEC. 1. DEG. 2. MIN. 3. SEC. D. RECEIVING WATER (name) 117 35 .00 13.00 32.00 85.00 5.00 3.00 Tennessee River

                         .4                4,            4.           4-              4           4            I.
                         .4                I.            l*           I-              4           4            I*
                         .4                4-            I.           4-              4           4            I.

II. FLOWS, SOURCES OF POLLUTION, AND TREATMENT TECHNOLOGIES A. Attach a line drawing showing the water flow through the facility. Indicate sources of intake water, operations contributing wastewater to the effluent, and treatment units labeled to correspond to the more detailed descriptions in Item B. Construct a water balance on the line drawing by showing average flows between intakes, operations, treatment units, and outfalls. If a water balance cannot be determined (e.g., for certain mining activities), provide a pictorial description of the nature and amount of any sources of water and any collection or treatment measures. B. For each outfall, provide a description of: (1) All operations contributing wastewater to the effluent, including process wastewater, sanitary wastewater, cooling water, and storm water runoff; (2) The average flow contributed by each operation; and (3) The treatment received by the wastewater Continue on additional sheets if

1. OUT- 2. OPERATION(S) CONTRIBUTING FLOW 3. TREATMENT FALL b. AVERAGE FLOW b. LIST CODES FROM NO. (list) a. OPERATION (list) (include units) a. DESCRIPTION TABLE 2C-1 ERCW.Screen and Strainer Backwash Discharge to surface water 0.0140 MGD 4 A 117

             -Outfall 117 was not sampled dtirng the 24-hour sampling evert tor the following reason, The ERCW is chemically treated; however, there are two injection locations. SON can iniect chemicals downstream of the stLiners and there is no pathwav for the chemicalS to be backwashed into the Tennessee River. However, SQN ias procedural controls in place t.o rerminate the chemical injection prior to back-washing. Also, NPDES p*rmit renewal o*nllinien f-r        TV. rn1-fire               _

plants with similar intakes do not imlnolo onelvr eel ,l*,'o tf f- r -ke screen backwash and this has been acceOtable to TOEt . FICIAL USE ONLY (effluent guidelinsc~sub-categories) EPA Form 3510-2C (8-90) PAGE I of 4 CONTINUE ON REVERSE

CONTINUED FROM THE FRONT C. Except for storm runoff, leaks, or spills, are any of the discharges described in Items I-A or B intermittent or seasonal? Z7 YES (complete thef[slowing table) FI NO (go to Section 11i)

3. FREQUENCY 4 FLOW 4 1. OUTFALL NUMBER (list)

2. OPERATION(s)

CONTRIBUTING FLOW (listý)eg WEEK (sp - i/y

b. MONTHS PER YEAR (spifyerge)

a. FLOW RATE (in mgd)

1. LONG TERM 2. MAXIMUM AVERAGE DAILY B. TOTAL VOLUME (specify with units)

1. LONG TERM 2. MAXIMUM AVERAGE DAILY C. DURATION (in dys) 117 ERCW Traveling Screen 4 12 0 .0100 0.0216 0.014 and ERCW Strainer Backwash 3 12 0 0040 0 .0096 0.0014 Ill.

PRODUCTION-A. Does an effluent guideline limitation promulgated by EPA under Section 304 of the Clean Water Act apply to your facility?- [Z YES (complete Item III-B) E] NO (go to Section IV) B. Are the limitations in the applicable effluent guideline expressed in terms of production (or other measure of operation)? El YES (complete Item II-C) 17 NO (go to Section IV) C. If you answered "yes" to Item Ill-B, list the quantity which represents an actual measurement of your level of production, expressed in the terms and units used in the applicable effluent guideline, and indicate the affected outfalls.

1. AVERAGE DAILY PRODUCTION 2. AFFECTED OUTFALLS

a. OUANTITY PER DAY b UNITS OF MEASURE c. OPERATION, PRODUCT, MATERIAL, ETC. (list outfall numbers)

a. b.QUANTITY UNITS OF PER MEASURE DAY (specify)

I IV.IMPROVEMENTS-A. Are you now required by any Federal, State or local authority to meet any implementation schedule for the construction, upgrading or operations of wastewater treatment equipment or practices or any other environmental programs which may affect the discharges described in this application? This includes, but is not limited to, permit conditions, administrative or enforcement orders, enforcement compliance schedule letters, stipulations, court orders, and grantor loan conditions. [] YES (complete the following table) [7 NO (go to Item IV-B)

1. IDENTIFICATION OF CONDITION, 2. AFFECTED OUTFALLS 3 BRIEF DESCRIPTION OF PROJECT 4. FINAL COMPLIANCE DATE AGREEMENT, ETC.

a. NO. b. SOURCE OF DISCHARGE. a. REQUIRED b. PROJECTED OPTIONAL: You may attach additional sheets describing any additional water pollution control programs (or other environmental projects which may affect your 4 ischarges) you now have underway or which you plan. Indicate whether each program is now underway or planned, and indicate your actual or planned schedules for construction.

LMARK "X" IF DESCRIPTION OF ADDITIONAL CONTROL PROGRAMS IS ATTACHED CONTINUE ON PAGE 3 Form 3510-2C EPA Form (8-90) 3510-2C (8-90) PAGE 22 of4 PAGE of 4 CONTINUE ON PAGE 3

EPA 1.D.NUMBER (copy from Item I of'Fo-rm 1) CONTINUED FROM PAGE 2 I TN5640020504 I V. INTAKE AND EFFLUENT CHARACTERISTICS I & C: See instructions before proceeding - Complete one set of tables for each outfall -Annotate the outfall number in the space provided. NOTE: Tables V-A, V-B, and V-C are included on separate sheets numbered V-1 through V-9. D. Use the space below to list any of the pollutants listed in Table 2c-3 of the instructions, which you know or have reason to believe is discharged or may be discharged from any outfall. For every pollutant you list. briefly describe the reasons you believe it to be present and report any analytical data in your possession.

1. POLLUTANT 2. SOURCE 1. POLLUTANT 2. SOURCE VI. POTENTIAL DISCHARGES NOT COVERED BY ANALYSIS Is any pollutant listed in Item V-C a substance or a component of a substance which you currently use or manufacture as an intermediate or final product or byproduct?

L.- YES (list all such pollutants below ) [] NO (go to Item VI-B) 4P 4 I CONTINUE ON REVERSE Form 3510-2C EPA Form

ý-:PA                  (8-90) 3510-2C (8-90)                                                      PAGE 3 PAGE   3 of4 of 4                                                          CONTINUE ON REVERSE

CONTINUED FROM THE FRONT TESTING DAT FVII. BIOLOGICAL TOXICITY Do you have any knowledge or reason to believe that any biological test for acute or chronic toxicity has been made on any of your discharges or on a receiving water in relion to yourdischarge within the last 3 years? I YES (identify the testis) and describe their purposes below) LUNO'(go to Section VIII) VIII. CONTRACT ANALYSIS INFORMATION Were any of the analyses reported in Item V performed by a contract laboratory or consulting firm? El YES (list the name, address, and telephone number of and pollutants analyzedby, 0 NO (go to Section IX) each such laboratoryor firm below) 4 A A. NAME B. ADDRESS C. TELEPHONE (areacode & no.) D. POLLUTANTS ANALYZED (list) IX.CERTIFICATI

   / certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel property gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significantpenalties for submitting false information, including the possibility of fine and imprisonmentfor knowing violations.

A. NAME & OFFICIAL TITLE (type orprint) I B. PHONE NO. (areacode & no.) Timothy P. Cleary, Site Vice President, Sequoyah Nuclear Plant (423) 843-7001

 &SIGNATURF                                                                                              D. DATE SIGNED IPIZWý P&01 PAGE 4 of 4 EPA Form 3510C (8-9)

EPA I.D. NUMBER (copy from Item I ofForm 1) Form Approved. OMB No. 2040-0086. Please print or type in the unshaded areas only. TN5640020504 Approval expires 3-31-98. APPLICATION FOR PERMIT TO DISCHARGE WASTEWATER I k N& EPAEXISTING c MANUFACTURING, COMMERCIAL, MINING AND SILVICULTURE OPERATIONS ConsoiidatedPermits Program NPIDES

1. OUTFALL LOCATION For each outfall, list the latitude and longitude of its location to the nearest 15 seconds and the name of the receiving water.

A. OUTFALL NUMBER B. LATITUDE C. LONGITLUDE (list) 1. DEG. 2.. MIN. 3: SEC. 1. DEG. 2. MIN. 3. SEC. D. RECEIVING WATER (name) 118 35.00 13 .00 .28.00 85.00 5.00 11.00 Intake Forebay II. FLOWS, SOURCES OF POLLUTION, AND TREATMENT TECHNOLOGIES A. Attach a line drawing showing the water flow through the facility. Indicate sources of intake water, operations contributing wastewater to the effluent, and treatment units labeled to correspond to the more detailed descriptions in Item B. Construct a water balance on the line drawing by showing average flows between intakes, operations, treatment units, and outfalls. If a water balance cannot be determined (e.g., for certain mining activities), provide a pictorial description of the nature and amount of any sources of water and any collection or treatment measures. B. For each outfall, provide a description of: (1) All operations contributing wastewater to the effluent, including process wastewater, sanitary wastewater, cooling water, and storm water runoff; (2) The average flow contributed by each operation; and (3) The treatment received by the wastewater. Continue on additional sheets if necessary.

2. OPERATION(S) CONTRIBUTING FLOW 3. TREATMENT FALL b. AVERAGE FLOW b. LIST CODES FROM NO. (list) a. OPERATION (list) (include units) a. DESCRIPTION TABLE 2C-1 ERCW Dredge Pond None Discharge to Surrface Water Noe4 .A 118 Sedimentation u IPond is not in service at this Filtration s18is i Q I time. Therefore, outfall inactive, only storrswater from surrounding vegetated area discharges. No industrial activity in area. If in service the pond would provide sedimentation during dredge activities ar-d filtration for lower depth waste waters.,

                -Outfall     l18 was not, sampled during he   24-hcý,',r naniie, eve,11     One                                                                        .-                               ____        ____

the inactivity. or the dredge pond. I 1 CIAL USE ONLY (effluent guidelines sub-categories) EPA Form 3510-2C (8-90) PAGE 1 of 4 CONTINUE ON REVERSE

CONTINUED FROM THE FRONT C. Except for storm runoff, leaks, or spills, are any of the discharges described in Items Il-A or B intermittent or seasonal? [] YES (complete the following table) ... NO (go to Section III)

3. FREQUENCY 4. FLOW

a. DAYS PER 8. TOTAL VOLUME

2. OPERATION(s) WEEK b. MONTHS a. FLOW RATE (i mgd) (specify with units)

1. OUTFALL CONTRIBUTING FLOW (spe ify PER YEAR 1. LONG TERM 2. MAXIMUM 1. LONG TERM 2. MAXIMUM C. DURATION NUMBER (list) (list) average) (specify average) AVERAGE DAILY AVERAGE DAILY (in days) 118 ERCW Dredge Pond (No dredging operations have been conducted SINCE July 1997. Flow cannot be predicted based on past.

Pond is presently vegetated and no industrial activity is conducted in the vicinity.

11. PRODUCTION ----

A. Does an effluent guideline limitation promulgated by EPA under Section 304 of the Clean Water Act apply to your facility? 0 YES (complete Item Ill-B) [:] NO (go to Section IV) B. Are the limitations in the applicable effluent guideline expressed in terms of production (or other measure of operation)? D] YES (complete Item Ill-C) NO (go to Section 1k) C. If-you answered "yes" to Item Ill-B, list the quantity which represents an actual measurement of your level of production, expressed in the terms and units used in the applicable effluent guideline, and indicate the affected outfalls.

1. AVERAGE DAILY PRODUCTION 2 AFFECTED OUTFALLS

a. QUANTITY PER DAY b. UNITS OF MEASURE c. OPERATION, PRODUCT, MATERIAL, ETC. . (list ouýfall numbers)

(specify) V IROVEMENTS PA. Are you now required oy any -ederal, State or local autnority to meet any implementation scneoule for me construction, upgrading or operations of wastewater treatment equipment or practices or any other environmental programs which may affect the discharges described in this application? This includes, but is not limited to, permit conditions, administrative or enforcement orders, enforcement compliance schedule letters, stipulations, court orders, and grant or loan conditions. DYES (complete the followving table) Z[] NO (go to Item IV-B)

1. IDENTIFICATION OF CONDITION 2. AFFECTED OUTFALLS 4. FINAL COMPLIANCE DATE 3 BRIEF DESCRIPTION OF PROJECT AGREEMENT, ETC.

a. NO. b. SOURCE OF DISCHARGE a. REQUIRED I b. PROJECTED 4 L I

OPTIONAL: You may attach additional sheets describing any additional water pollution control programs (or other environmental projects which may affect your I ischarges) you now have underway or which you plan. Indicate whether each program is now underway or planned, and indicate your actual or planned schedules for construction. [] MARK x IF DESCRIPTION OF ADDITIONAL CONTROL PROGRAMS IS ATTACHED EPA Form 3510-2C (8-90) PAGE 2 of 4 CONTINUE ON PAGE 3

EPA I.D. NUMBER (copy from Item I of Form])) TNN564 0020 504 I CONTINUED FROM PACE 2 [V.INTAKE AND EFFLUENT CHARACTERISTICS A b B, & C: See instructions before proceeding - Complete one set of tables for each outfall - Annotate the outfall number in the space provided. NOTE: Tables V-A, V-B, and V-C are included on separate sheets numbered V-i through V-9.

    "D. Use the space below to list any of the pollutants listed in Table 2c-3 of the instructions, which you know or have reason to believe is discharged or may be discharged from any outfall. For every pollutant you list, briefly describe the reasons you believe it to be present and report any analytical data in your possession.

1. POLLUTANT 2. SOURCE 1. POLLUTANT 2. SOURCE VI. POTENTIAL DISCHARGES NOT COVERED BY ANALYSIS Is any pollutant listed in Item V-C a substance or a component of a substance which you currently use or manufacture as an intermediate or final product or byproduct?

.. dhý III YES (lis oi su/ch pollutots below ) 117NO (go to Item V-B) I I EPA Form 3510-2C (8-90) PAGE 3 of 4 CONTINUE ON REVERSE

CONTINUED FROM THE FRONT VII. BIOLOGICAL TOXICITY' TESTING DATA Do you have any knowledge or reason to believe that any biological test for acute or chronic toxicity has been made on any of your discharges or on a receiving water in relation to your discharge within the last 3 years?

 &              ]   YES (identrfy the testt(v) and describe theirpurposes below)         .                     [7  NO (go to Section VI11) 1W VIII. CONTRACT ANALYSIS INFORMATION Were any of the analyses reported in Item V performed by a contract laboratory or consulting firm?
               -  1 YES (list the name, address, and telephone number of anrpollutanct analyzed by,                NO (go to Section IX).

each s-ch laboratory orfirm below) I B. ADDRESS C. TELEPHONE (areacode & no.) D. POLLUTANTS ANALYZED (list) IX.CERTIFICATION I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel property gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate,and complete. l am aware that there are significantpenalties for submitting false information, including the possibility of fine and imprisonmentfor knowing violations. A. NAME & OFFICIAL TITLE (type orprint) B. PHONE NO. (area code & no.) Timothy P. Cleary, Site Vice President, Sequoyah Nuclear Plant (423) 843-7001

   ~SIGNATURE                                                                                           D. DATE SIGNED I

EPA Form 3510-* 890, PAGE 4 of 4

TENNESSEE VALLEY AUTHORITY (TVA) SEQUOYAH NUCLEAR PLANT (SQN) - NPDES PERMIT NO. TN0026450 APPLICATION FOR RENEWAL . Current Whole Effluent Toxicity (WET) Requirements: Outfall 101 - 7-day or 3-brood IC25 ->45.2% [IWC = 45.2% effluent (2.2 TUc)] Monitoring Frequency Governed by B/CTP: 1/year when oxidizing biocides used 1/year when non-oxidizing biocides used Proposed WET Requirements: Outfall 101 - 7-day or 3-brood IC25 Monitoring Trigger 42.7% (2.3 TUc) Monitoring Frequency Governed by B/CTP: 1/year when oxidizing biocides used 1/year when non-oxidizing biocides used

Background:

The current permit, effective September 1, 2005, requires chronic toxicity biomonitoring at a frequency governed by the B/CTP and with a permit limit IC25 45.2%. Previous to the issuance of the current permit, Outfall 101 demonstrated No Reasonable Potential for excursions above the ambient water quality chronic (CCC) criterion using historical effluent data. This demonstration of No Reasonable Potential has been maintained throughout the current permit cycle as evidenced in the accompanying historical effluent data for the last 20 studies. Based on guidance in EPA's Technical Support Document (TSD) for Water Quality-based Toxics Control (EPA/505/2-90-001), a permit limit is not required when No Reasonable Potential exists for excursions above the CCC. In this situation, the TSD recommends that biomonitoring be conducted at a frequency of once every 5 years as part of the permit renewal process. Proposed Changes:.

1. TVA requests that the current permit's requirement for the B/CTP to govern the frequency of biomonitoring remain (i.e., once per year when oxidizing biocides are used, and once per year when non-oxidizing biocides are used).

2. TVA requests that the current permit limit be replaced with an IC25 Monitoring Trigger = 42.7%, which is based on revised effluent flow, and is consistent with the TSD guidance for effluents demonstrating No Reasonable Potential. Toxicity at the instream wastewater concentration (IWC) would serve only as a hard trigger for accelerated biomonitoring, and not as a permit violation as indicated in the current permit.

0

3. TVA requests that all permit language referencing the "Permit Limit" be changed to "Monitoring Limit", and all references to "a violation of this permit" be removed.

Suggested language for exceedance of the monitoring limit might include:

        "Toxicity demonstrated by the tests specified herein shall serve as a trigger for accelerated biomonitoring." (page 20 of 25, paragraph4, sentence 2, currentpermit)
        "Effluent toxicity that is not consistent with the intake toxicity conditions specified above shall serve as a trigger for accelerated biomonitoring."

(page 20 of 25, paragraph4, sentence 5, current permit)

        "In addition, the failure of a follow-up test shall serve as a trigger for accelerated biomonitoring." (page 21 of 25, paragraph1, sentence 4, current permit)
        "Toxicity demonstrated in any of the effluent samples as Specified above shall serve as a trigger for accelerated biomonitoring." (page R-23 of R-49, paragraph 1, sentence 2, current permit)

4. TVA requests changes from the current "Permit Limit" to the appropriate "Monitoring Limit" as follows:

Page 20 of 25, table ýfollowing paragraph2: Effluent 100% ML)/2 (100 +(ý11ý)2 (MoL)~?m Monitoring LimitL Z. X L 02.5 XL M Control] oto Effluent (NI fL) 0n 100 71.4 42.7 21.4 10.7 0 Page 20 of 25, paragraph4, sentence 1:

        "Toxicity will be demonstrated if the IC25 is less than the monitoring limit indicated in the above table."

5. TVA also requests that the Wastewater Flow in the table found in Section XI of the permit rationale be changed to 1491 MGD, with the DF = 2.3 and the revised IC25_ 42.7.

TVA recommends that all other text in Section E of the permit and Section Xi of the permit rationale remain unchanged. Dilution and Instream Waste Concentration Calculations Outfall 101: Average.Discharge = 1491 MGD Tennessee River 1Q10 = 3491 MGD Dilution Factor (DF): DF= Qs 3491 =2.34

                    -             Qw   .1491 IWC- Qw       14 9 1  x 00o 42.7%

Instream Wastewater Concentration (IWC): Qs 3491 2

Reasonable PotentialDetermination: The last 20 studies for Outfall 101 were used for determining Reasonable Potential, with all studies resulting in no observed toxicity (<1.0 TUc) and a coefficient of variation equal to zero. This outcome demonstrates that no Reasonable Potential for excursions above the CCC exists, based on data obtained from testing conducted under the current operating conditions. Historical data for the last 20 studies follows, and is followed thereafter with documentation of chemical additions which occurred during sampling for toxicity tests for Outfall 101. 3

SQN Documentation: Summary of SQN Outfall 101 WET Biomonitoring Results ** Acute Results Chronic (96-h Survival) Results

                                                                % Survival       Study     Study Toxicity   tocy in Units    Toxicity Undiluted Test Species             Sample          (TUa)   Units (TUc)

Test Date

55. Jan 14-21, 2003 Ceriodaphniadubia 100 <1.0 <1.0 Pimepnales promelas 10

56. Apr 8-15, 2003 Ceriodaphniadubia 100 <1.0

                                                                                  <1.0 Pimephales promelas            100

57. Jun 17-24, 2003 Ceriodaphniadubia 100 <1.0

                                                                                  <1.0 Pimephales promelas            100

58. Aug 5-12, 2003 Ceriodaphniadubia 100

                                                                                  <1.0      <1.0 Pimephales promelas            100

59. Oct 7-14, 2003 Ceriodaphniadubia 100 <1.0

                                                                                  <1.0 Pimephalespromelas             100

60. Feb 3-10,2004 Ceriodaphniadubia 100 <1.0 90 <1.0 Pimephales promelas

61. May 6-13,2004 Ceriodaphniadubia 100 <1.0

                                                                                  <1.0 Pimephalespromelas             100

62. Jul 7-14, 2004 Ceriodaphniadubia 100

                                                                                  <1.0      <1.0 Pimephales promelas            100

63. Nov 9-16, 2004 Ceriodaphniadubia 100 Pimmnnhoclno nrnmmino inn <1.0 <1.0 n 40 20 20 Maximum 100 <1.0 <1.0 Minimum 90 <1.0 <1.0 Mean 99 <1.0 <1.0 CV 0.00 0 **Last 20 studies only were included for determining RP.

0.03 Shaded area includes data collected under the current permit. 0.00 4

  *Sequoyah Nuclear Plant Diffuser (Outfall 101) Discharge Concentrations of Chemicals Used to Control Microbiologically Induced Corrosion and Mollusks, During Toxicity Test Sampling, March 12, 1998 -October 31, 2008 Date            S~lm               Towerbrom       PL22             PCL-401    C.3    .Cuprostat   P iy~c~rite       mg/L          m4mgL                   m/   MA         mg/L ILTRC            P8pt             Copolymer                 Azole 03/112/1 998           ',016                         ..........

03.13/199 . .... 03/143/1998 fl0,0 ........... .. ......... 3511 998 ...... .... ..... 03/16/199 - 03/17/1 998 ~02- 8 03/18/1998 .......... 09/170/1998 ........ ..... 0021. K 0911198 .03.- ........ .. 0019 09/182/1998 ~-~ 01 09/13/1 998 .~4:0015 0.01 09/14/1 998 3,0 0.015 n 9 /........

• I - .........

02/23/1 999 02/24/1 999 02/25/1 999 02/26/1 999 02/27/199 9 02/28/1999 08/18/19ý99 0.015 0.024 08/19/1999 0.012 0.024 08/20/1 999 0.023 0.024 0.120 08/21/1 999 0.022 0.024 08122/1 999 0.022 0.024 08/23/1999 0.025 0.024 08/24/1999 0.016 0.023 011/31/2000 < 0.002 0.009 02/01/2000 0.011 0.028 02/02/2000 0.028 0.009 02103/2000 0.008 0.009 02/04/2000 0.006 0.009 0.109 02/05/2000 < 0.002 0.009 02/06/2000 < 0.002 0.009 07/26/2000 *<0.0057 0.019 07/27/2000 0.019 0.019 07/28/2000 0.0088 0.018 0.108 07/29/2000 < 0.0088 0.019 07/30/2000 .<0.0076 0.019 07/31/2000

• 0.0152 0.019 08/01/2000 *<0.0141 0.019 12/11/2000 0.0143 0.020 12/12/2000 0.0092 0.020 12/13/2000 *<0.0120 0,020 12/14/2000 *<0.0087 0.020 12/15/2000 0.0120 0.020 12/16/2000 *<0.0036 0.020 12/17/2000 *<0.0036 0.020 08/26/2001 0.017 0.021 08/27/2001 <0.0096 0,021 08/28/2001 <0.0085 0.021 08/29/2001 <0.0094 0.020 08/30/2001 <0.01 23 0.021 08/31/2001 <0.005 0.020 11/25/2001 <0.0044 11/26/2001 <0.01 19 0.02 11/27/2001 0.0 137 0.019 11/28/200 1 <0.0089 0.019 11/29/200 1 0.0132 0.02 11/30/200 1 < 0.0043 0.02 5

Sequoyah Nuclear Plant Diffuser (Outfall 101) Discharge Concentrations of Chemicals Used to Control Microbiologically Induced Corrosion and Mollusks, During Toxicity Test Sampling, March 12, 1998 -October 31, 2008

• Date Sod**m:

Hpochi*ot*iX Towerbrom mg/L PCL-222 mL PCL-401 mg/L mg/L CL-*

Ii Cuprostat-PF mg/L 30M mT4L TRC

::: Phoi ht* ...... Copolymer

..................................... Azole  :,..............  :..:::::

TRC 12/09/2001 <0.0042 .... 12/10/2001 X:004 12/11/2001 <0.0104. 12/12/2001 0.0128 fl40.02 12/13/2001 <0.0088 0 02

                                                                                                                                                                    .04 12/114/2001                                       *   ~          ~ 0.0134~                              ~
                                                                                                           .. . . .. ...... ::                             :x : :::

0.02 ......... ... 1.............. ~*!  ! !i!!i*!~* 01/02/2002 < 0.0079 002 0.02 0.006 ".023 01/03/2002 - <0420.014 01/04/2002 0.0124 N024' 0..... 0 014 000 01/05/2002 < 0.0042 j 01/06/2002 . < 0.0042 .-... .. ...... 01/07/2002 *.<0 0.089 0.024' 0.014 006 02/26/2002 0.0143 00023 0.023 02/27/2002 <<00041 ......... 0.023 .......... 02/28/2002 <000041 0. 0 008 ... 03/01/2002 .< 0.0041 0.024:::: 0.008 05/05/2002--. 05/06/2002 ::  :.::: 0.02 . .......... 05/07/2002 . . .... .... .- 0.02 08/07/2002

                      ..          ....   .::::                                    <0.0107                                  0005..0019..0..

085/2/00 0 2 .. *:::ii:::**  ::!i*:::* ............. ..................................................

 *08/09/2002 O812OO i,~:,.....

08/08/2002 005

                                                                                                           *iii,',:i*i,!
                                                                                                                              * ...          i,*,*i*ii*i*         . 18 . . . . ..

0.0190.0061..0019 008200

                                                                                                                                                                                                       ....                         ';,:**i**i* 4 i,;**

10/0 /200 0.0049.... ....... 105/107/2002 - 05 04 0018900 108/08/2002 ~ <0002.040018 ......... 7.. 108/09/2002 08/09/2002 . - 0.0124

                                                                                  <0.01052                              D~6                                    0.018 0.012                     00
               *~~...                                                               0.13....00                                                               101/20      8.0         .... ..

108/11/2002 06/06/2002 . . ..: <0.0041

                                                                                 <200.0042                    ... ... . .0,058:
                                                                                                                            ......... ....     ;...0.05
                                                                                                                                          ;. ...    ...            018 . . . ... . . X. .:--..:i. ...                                : :: : :: : :: : :: :: : : :: : ::

01/1/203...........<0003 ..... 1 0 ...

                                   / 9.../2... 0 2...... .....                     0 .0 2 4                 ..........................                        0. 18............             ....1*!   ::::i;:::;i::!:i
                                                                                                                                                                                                             ...                     ...                i 10/109/2002                                   ii~iiiiXl~iiiiiii        0.0134                   .. iiii          i              ...... : 18 iiiiii~ii                         iii!i!i:i: i             i:ii:i:i 101/10/2002         *:**;!iiiiii!:i!i*:!i:*il                        <0.01 34 ~ ~~:::::::~~~~~~~~:::::::          .........     ........          0 0 18i:::::*                     :::::::::::::::::::::::::::         iii**!*!ii~!;!!i~~i~;

04/08/20032 <0.01170.1 04/108/20032 <0.01106001 0019

                                                                             ....................... ....... ...........                                                                                                            iii::i:]:;iiii

iiiii:.............:i~i

            ,0 1114 /2 0 0 3 i:ii*:i:;~i:i:3:*         i:i::ii;i:;:i!             < 10.0 0 71                      ::::::

18 0:.0:2...0

                                                                                                                                                       ;*;;:?.:i::::;::::*:::                    ::iiii:2i:E::ii::

01 0 / 00/15/2003 0 01 9

                                                                                  <0.0063                  ...............................                     0.020::*;:!i
                                                                                                                                                                  . 2         i:*:::i*iii~**ii*~i~!il;i~iiii!~iiii*i:**

0411 /2003 iii!ii!tiii*iiii*; ii*i:iiii:iitl <0.0073 *-iiiii-~*ii i[~ii~ii;i~ 0.009 i~i!iiiiiii*i*~ !i!!*ll~iiiiii

                                                                                                                                                                                                   .. .....                              :*;~::*~*:i*;:::i::i~

04/06/2 003  ::::::::::**::ii ii!::!:. :::: . <0.0073 ............... iiii~i  :**,,,*;** *,;*] 06/107/2003  ::iiiiiiiiiiiiiiii:;:i.i ii~i < 0.01089 i:: :i::~* i:i:i:i::i

                                                                                                                                              ....             0.021          w.,iiiiii lii*iiii ii ii:i;i:iii::;                                    i            :iii 04109/2003          i~:::~:::::::::::;!:-::                          < 0.01048                   .... .. ...                                      0.021                    o M om.*:::**::*:i:::i*::::ii::::*;:
                                                      ':':::'::::::::::::~..
                                                                                                                                   ......  ...                                                                                       ::*******::::~       ~:******

6

Sequoyah Nuclear Plant Diffuser (Outfall 101) Discharge Concentrations of Chemicals Used to Control Microbiologically Induced Corrosion and Mollusks, During Toxicity Test Sampling, March 12, 1998 -October 31, 2008 Date 0 S oditim, yoooitslý Towerbrom mg/L TRC mglL PhoCphate

2-22 PCL-401 mg/L Gopolymer

                                                                                                                                                                   'AJLMAC          . ....
                                                                                                                                                                                                 .:::iC   CuprostatPF mg/L Azole HS:OM i/L Qia
                                                                           <0.0050.                                                                                                                                         ........

08/03/2003 . 08/04/2003 <0.0050 0:058 0.020 ........ .. 0.020- .:.-.:..:.:..,....:... :. 08/05/2003 -<0.0051 0,057

.:..:.:.:.:......++ , ......... .+.,:

08/06/2003 - <0.0084 la.D57 0.020 ........ . ............ ... . 08/08/2003 08/07/2003  ::::::::::::::::::::::::::::::: 00.010 229 (tQ i i i0.0153 i 57 0.020 0000iii~* itt:::::::::::::::::::::::::::::::0:::::020::: 5 iiiii:i:;: * ;.i*: 010/06 2003 - 10/05/2003 <0:::::::::::::::::::::::::::::::::

                                                                                 .0043
                                                                            <0.043.....0.02                           0057:::::::

::::::::::::: 0.020  : ::::::::::::::::: ~i  ;;;0025:::::::::::::

                                                                                                                                                                                                                                ....      i iiiiiii 10/05/2003                        10/7/003.. <0.0043                                                 '           0                            0  020...

0.020 4.... .0.09 .5 ..... 0 ...... 108/08/2003 <0.01503 05 0.020 02 0..0...00.. <0.0090 00267.....0 009 10/08/2003 <0.0106 0.018. 0.020 0.019 .......... 0 0.. 10/09/2003 010/0/2004 105/0/2004 . .03 23. 0.014. .:... 0,57 0.014 0.0209..... ...... ...... - 02102/200.. 0.034 0...000 ... 010/0 /2004 0012.0...009...0 .. 07/08/2004 0.0223 0057 0019 0.009 ..................

                                                ...        .......                                         .,,..........+ .+ . . : . .                                                                                    :::::::% ::::::::::::

02105/2004 05/0720040.0227  : !;ii~i <!ii:*!**:!# 0.01034

... 6i::i::i::!: .08

• *::ii::i::i

...... 0.0202 0.009 ........ iiii!i~ii *i:::::i:i:::i~;;ii ::i:::i~::!

i~ .......... 105/109/2004 .<.. 0.018305 0.0204

. . .i i i i i.................

i iii ........ ..... 07/09/2004 <0.0180057042 0.009Ji;:*i* i!i!**!iiii~iii~ ** i!*~iii:*iii~~i~i .... ~~05105/2004  :::: ** *~ii:::i::

                                                                                                                                 ý6~~!?            0.014                                     .......
                                                  ........ <0.0085w
                                         .......                                                          ...............................................................                                                   iiiiii* * !ii 0 5 /0 6 /2 0 0 4         ::iii::::i::::::*:i:::::i::::::ii::i:::
                                        .....                              <::i 0 .0 14 6                    '                0 37 iiili:

13':iiiii~ 0 .0 13 ................................................. 070/0084/2 ~ ~i~i~;::-!!*i~iii;ii;*ii~ii~~

                                               ...    ....                       02 2 3                       :iiiiii i                                             ::::::::::::i*         ...:::::::::::
                                                                                                                                                                                 ..............                           i:i::ii:i::::i::!!i*:;i:i::::i:

05/07/2004 0 ..0227 18  :::iii:l:i:*_58 *i :i~ii:i:!i:i 0 020;*;!i 0 0  ::i:::[:i:::i::*::::::::::::::::::  ::::::::::*::*:*:::i:i::i:i:::

                                                                                                                                             .7

Sequoyah Nuclear Plant Diffuser (Outfall 101) Discharge Concentrations of Chemicals Used to Control Microbiologically Induced Corrosion and Mollusks, During Toxicity Test Sampling, March 12, 1998 -October 31, 2008 Date SodIum Towerbrom  :.pC:t:fl . PCL-401 CLS53 Cuprostat-PF H:ýOm1- Nalco ftpoobkdt mg/L mg/L mg/L mgkLQual 73551 mg/LI TRO Phsht opolymer .... Azole mg/L TR.... ....... /P 11/07/2004 -<0.01 87 .0.014 .............. 11/08/2004 - <0.0192 0.03 .. ..... 11/09/2004 11/10/120044>08:.. 11/11/2004 iiiiiii:iiiiiiiiiiiiii <0.0233

                                                               <0.0149
                                                               <0.0149.. ...........             .: A 047iii           !iiiiiiiii              0.016 0.016.

0017 . .. iiii~ 0<041 ~_-..i:ii:l 044$iiiiiiiii~iiiiiiiiiiili 1.................. 0.. 3... .. 1 ................ . 02106/20045 :ii:i:i:i::i::::*iiiii::;::i: 02/07~<0.01 i~i~:!:i*!.:!::!::::*::!:**:*::i::*

                                                               <0.0025                      ::':::+::':':::::::

0028tiiii~ i  ::: {iiiiiil 0.010 0~7......... ' " "" "'" " " "..-......--.-....-..-..-..-...-.

                                                                                                                                                                                                 ........                                      :!~~iii                      iiiii
                                                               <0.00806                                     0                                                                                                            -:::::::::::::::::::::::::::::::::::

02/108/2005 0028..0010... 02/09/2005 <0.01999

                                                               <0.0425038 0.010                         ...........    ..........

02/10/20054 0.010 ............... 06/06/2005 <0.0043 ........ 02/11/2005 0.0155 .

                                   -::::::::::::::::::::::::::::::                              iiii 0 02 ::::::::::::::::::::::::::::::::::::::%

8:i:ii:i:ii: 0.010  :::::::::::::::::::::::::::::::

                                                                                                                                                                                           -                             -                     :::::::::::::::::::::::::::::::        : 0.007 06/08/2005                                                    <0.0295.....

06/10/2005 000184

%:::::::::::::::::::::::::::::::.:.+:.: :+:..:.::.:..:+::.:. ... . "..::........::::.::........::

06/07/2005 <0.0103 16 , 0.007 06/09/2005 07/19/2005 0.0129 0.0163 02809 ... 0.0 0 ......... ............ 106/306/2005 0.0068 0.00 0.009 07/18/2005 0.01502 11/02/2005 0.0104 11/03/2005 0.0117 07/17/2005 0.0231

                                                                    .00 8 10/ 0/ 005:.:::i:!!i!:i:!i:::::i*:i::iii:i::::::i:i!           . ... ...

i:i:i:!:i:i::iiiiiiii~iiiii~iiiiiiiilii!!ii~ii~~iiiiii;;i::iiiiiiililiiiiiii ........*..........

                                                                                                                                                                                               .............. !:!i:i:::i:i::::::::.                                   .........

i::::i 11/04/2005 10/ 10.0165j,

                                                                  /2.0 051::iii:i:iii;:::::::i~i 2                   :::i:ili:i:i!ii:i:ii iiii~iii;iiiiiiliii  iiiiiiiiiiiiiiii;;iiii~ii*;iiiiiii~i~ii~iii               .... iii~i~i!iiiiiiiiiii~iiii                                     ; :::iii[::i:i:iiii::.:ii..........i:i:ii 11 0/ ii;::iii:i::il 05.i:;i:l:i:i;::i:~           .0 0                    ::::::::0 :ji:::::i::iiii:            i:;;i;i;::::::   .0 0 9                                     ::!iiiii;;:::                                     l:il::iii:ii* ::i::ii:;i::i 0 .0 14:::::

J 71/202 /2 0 0 5 -::* !!::!: :::::*:::i, 011/14/2005 . 1 94 00.0274  ::*:::i::!i::i:::::..:-.i:.020

                                                                                                   ....    ... .....                                                        :ii:i:i::i:i:::*::i:i::i:i:::i:!i:!::::[::::iii::::::*4::.....~*!::::::
                                                               " : : : :: :: :: :: :iiiiiii~i!!*iii!!!*

!i**!ii*!!*ii[!iii  :::::::::::::::::::::::::::::::::::

                                                                                                                                                                                             .....                                            [.....            :...:.::.:...:![:

111/20 0.0234 D. 000 011/18/2005 7 /2 2 /2 0 0 5 ! :::i:!! !i*: i:::::i~i::ii: 00.0200 .023 8 0 .0...........18........................................... 0 -. ........... 0 1.......... 11/19/2005 0.01163 0.0-

                                                                                                                                                                                  . - .......... . .                                             :x > x+ x > > :

1!1i:*

                        / i[i!!:.!:*::::i~ii::*i:;;:

9/ 00 001 6 .............................................. ................. 8

Sequoyah Nuclear Plant Diffuser (Outfall 101) Discharge Concentrations of Chemicals Used to Control Microbiologically Induced Corrosion and Mollusks, During Toxicity Test Sampling, March 12, 1998 -October 31, 2008 -we-11/12/2006 Towerbrom mg/L TRC 0.0055 PCL-401 mg/L Copolymer prostat-PF mg/L Azole Nalco 73551 mg/L EO/PO MSW 101 mg/L Phosphate 11/13/2006 0.0068 11/14/2006 0.0143 11/15/2006 0.0068 11/16/2006 0.0267 11/17/2006 0.0222 11/26/2006 0.0188 11/27/2006 0.0138 11/28/2006 0.0120 11/29/2006 0.0288 11/30/2006 0.0376 12/01/2006 0.0187 05/28/07 0.015 05/29/07 0.015 05/30/07 0.0084 0.017 0.015 05/31/07 0.0103

• 0.015 06/01/07 ý0.0164 0.017 0.015 06/02/07 0.0305 0.015 12/02/07 0.0241 12/03/07 0.0128 12/04/07 0.0238 12/05/07 0.0158 12/06/07 0.0162 12/07/07 0.0175 04113/08 0.0039 04/1 0.0124 04/1S 0.0229 04/11W 0.0143 04/17/08 0.0120 04/18/08 0.0149 10/26/08 0.0260 10/27/08 0.0151 0.017 10/28/08 0.0172 10/29/08 0.0154 0.018 0.030 10/30/08 0.030 10/31/08 0.0086 0.030 9

Biological Monitoring of the Tennessee River Near Sequoyah Nuclear Plant Discharge 2003 by Dennis S. Baxter Kenny D. Gardner Donny R. Lowery June 2004 Final Aquatic Biology Lab Norris, Tennessee

Table of Contents Pane Introduction 1 Methods 2 Fish Community 2 Benthic Macroinvertebrate Community 4 Sport Fishing Index 4 Spring Sport Fish Survey .5 Results and Discussion 5 Fish Community 5 Benthic Macroinvertebrate Community 6 Sport Fishing Index 6 Spring Sport Fish Survey 6 Literature Cited 8 List of Tables Table 1. Scoring Results for the Twelve Metrics and Overall Reservoir Fish Assemblage Index for Chickamauga Reservoir at the Sequoyah Downstream Sampling Station, 2003. 9 Table 2. Scoring Results for the Twelve Metrics and Overall Reservoir Fish Assemblage Index for Chickamauga Reservoir at the Upstream Sampling Station; 2003. 10 Table 3. Recent (1993-2003) RFAl Scores Collected as Part of the Vital Signs Monitoring Program Upstream and Downstream of Sequoyah Nuclear Plant. 11 Table 4. Species Listing and Catch Per Unit Effort for the Embayment and Sequoyah Transects During the Fall Electrofishing and Gill Netting on Chickamauga Reservoir, 2003 (Electrofishing Effort = 300 Meters of Shoreline and Gill Netting Effort = Net-Nights). 12 Table 5. Species Listing and Catch Per Unit Effort for the Transition and Inflow Transects During the Fall Electrofishing and Gill Netting on Chickamauga Reservoir, 2003 (Electrofishing Effort = 300 Meters of Shoreline and Gill Netting Effort = Net-Nights).. 13 1

List of Tables (continued) Page Table 6. Individual Metric Ratings and the Overall Benthic Community Index Score for Upstream and Downstream Stations near Sequoyah Nuclear Plant, Chickamauga Reservoir, November 2003. 15 Table 7. Average Mean Density Per Square Meter of Benthic Taxa Collected at Upstream and Downstream Stations near Sequoyah Nuclear Plant, Chickamauga Reservoir, November 2003. 16 Table 8. Recent (1994-2003) Benthic Index Scores Collected as Part of the Vital Signs Monitoring Program at Chickamauga Reservoir Transition (TRM 490.5 and TRM 482) and Forebay Zone (TRM 472.3) Stations. 19 Table 9. Sport Fishing Index Results for Chickamauga Reservoir, 2003. 19 Table 10. Sport Fishing Index Population Quantity and Creel Quantity and Quality Metrics and Scoring Criteria. 20 Table 11. Sport Fishing Index Population Quality Metrics and Scoring Criteria. 22 Table 12. Electrofishing Catch Rate, Mean Weight, Percent Harvestable, Numbers of Black Bass Greater than Five Pounds, Numbers of Black Bass Greater than Four Pounds and Largest Black Bass Collected, Chickamauga Reservoir Black Bass Surveys, 1995-2003. 22 Table 13. Black Bass Catch Per Hour Compared to Habitat Types by Location. 23 Table 14. Black Bass Catch Per Hour Compared to Habitat Types by Reservoir. 23 List of Figures Figure 1. Parameters used to calculate the Sport Fishing Index (SFI). 24 Figure 2. RFAI scores from sample years between 1993 and 2003. 25 Figure 3. Sport Fishing Index results for Chickamauga Reservoir between 1997 and 2003. 26 Figure 4. Chickamauga Reservoir length frequency histogram, (all sites) spring 2003. 27 Figure 5. Relative stock density values for Tennessee River Reservoirs. 28 ii

List of Figures (continued) Page Figure 6. Proportional stock density values for Tennessee River Reservoirs. 29 Figure 7. Chickamauga Reservoir mean relative Weights (Wr) for largemouth bass broken out by RSD category and fish numbers. 30 Acronyms BI Benthic Macroinvertebrate Index BIP Balanced Indigenous Population NPDES National Pollutant Discharge Elimination System PSD Proportional Stock Density QA Quality Assurance RFAI Reservoir Fish Assemblage Index RSD Relative Stock Density RSDM Relative Stock Density of Memorable-sized RSDP Relative Stock Density of Preferred-sized RSDT Relative Stock Density of Trophy-sized SAHI Shoreline Assessment Habitat Index SFI Sport Fishing Index SQN Sequoyah Nuclear Plant SSS Spring Sport Fish Survey. TRM Tennessee River Mile TVA Tennessee Valley Authority VS Vital Signs Wr Relative Weight iii

Introduction " Section 316(a) of the Clean Water Act specifies that industrial, municipal, and other facilities must obtain permits if their discharges go directly to surface waters. Industries responsible for point-source dischargers of heated water can obtain a variance from state water quality standards if the industry can demonstrate compliance with thermal criteria by documenting.the maintenance of Balanced Indigenous Populations (BIP) of aquatic life in the vicinity of its discharge. Sequoyah Nuclear Plant's (SQN) current National Pollutant Discharge Elimination System (NPDES) permit number TN0026450 states, "For Section 316(a), the permittee shall summarize previous data and indicate whether significant changes have occurred in plant operation, reservoir operations or in stream biology that would necessitate that significant changes to the permitted variance." The permittee shall use the Reservoir Fish Assemblage Index (RFAI) to assess Chickamauga Reservoir fish community health. Any apparent declines in the fish community health will be further investigated to discover whether the decline is a valid conclusion and if the decline is real to identify possible sources for the fish community decline. As part of the identification of potential sources for the decline, the instream effects of the discharges made under this permit will be investigated (TDEC 2000). In response to this requirement, Tennessee ValleyAuthority's (TVA's) Vital Signs (VS) monitoring program (Dycus and Meinert 1993) will be used to evaluate areas of Chickamauga Reservoir upstream and downstream of SQN discharge. The purpose of this document is to briefly summarize and provide Tennessee Department of Environment and Conservation the results of comparisons between current and historical monitoring data. Prior to 1990, TVA focused on reservoir ecological assessments to meet specific needs as they arose. In 1990, TVA instituted.a Valley-wide VS monitoring program which is a broad-based evaluation of the overall ecological conditions in major reservoirs. Data is evaluated with a multi-metric monitoring approach utilizing five environmental indicators: dissolved oxygen, chlorophyll, sediment quality, benthic macroinvertebrate community, and the fish community. When this program was initiated, specific evaluation techniques were developed for each indicator, and these techniques were fine-tuned to better represent ecological conditions. The outcome of this effort was development of multi-metric evaluation techniques for the fish assemblage (i.e., RFAI) and the benthic community, as described below. These multi-metric evaluation techniques have proven successful in TVA's monitoring efforts as well as other federal and state monitoring programs. Therefore, they will form the basis of evaluating these monitoring results. For consistency, only RFAI analyses between 1993 and 2003 will be utilized. The Benthic Macroinvertebrate Index (BI) is used primarily to support the RFAl analysis: In the past, the Sport Fishing Index (SFI) was used in support of a thermal variance request at SQN (TVA 1996). The SF1 was developed to quantify sport fishing quality for individual sport fish species. The SFI provides biologists with a reference point to measure the quality of a sport fishery. Comparison of the population sampling parameters and creel results for a particular sport fish species with expectations of these parameters from a high quality fishery (reference conditions) allows for the determination of fishing quality. Indices have been developed for 1

• black bass (largemouth, smallmouth and spotted bass), sauger, striped bass, bluegill, and channel catfish; Each SFI relies on measurements of quantity and quality aspects of angler success and.

fish population characteristics. In recent years, SFI information has been used to describe the quality of the resident fishery in conjunction with compliance monitoring, thermal variance requests, and other regulatory issues at TVA nuclear plants in Tennessee. Similar NPDES compliance monitoring programs using the methodologies described above are also being performed at Colbert and Widows Creek Fossil Plants in Alabama. The TVA Spring Sport Fish Survey (SSS) is conducted to evaluate the sport fish population of TVA Reservoirs. The results of the survey are used by state agencies to protect, improve and assess the quality of sport fisheries. Predominant habitat types in the reservoir are surveyed to determine sport fish abundance. In addition to accommodating TVA and state databases, this surveying method aligns with TVA Watershed Team and TVA's Reservoir Operations Study objectives. Sample sites are selected using the shoreline habitat characteristics employed by the Watershed Teams. The survey predominantly targets three species of black bass; (largemouth, smallmouth, and spotted bass) and black and white crappie. These species are the predominant sport fish sought after by fisherman. Methods . Fish Community Reservoirs are typically divided into three zones for VS Monitoring - inflow, transition and forebay. The inflow zone is generally in the upper reaches of the reservoir and is riverine in nature; the transition zone or mid-reservoir is the area Where water velocity decreases due to increased cross-sectional area, and the forebay is the lacustrine area near the dam. The Chickamauga Reservoir inflow zone is located at Tennessee River Mile (TRM) 529.0; the transition zone is located at TRM 490.5, and the forebay zone is located at TRM 472.3. The VS transition zone, which is located approximately 7.2 river miles upstream of the SQN discharge (TRM 483.3), will be used to provide upstream data for the 316(a) thermal variance studies performed in sample years between 1993 and 2003. An additional transition station was later added downstream of the SQN discharge to more closely monitor Chickamauga Reservoir aquatic communities in close proximity to the SQN thermal effluent. This station is located at TRM 482.0 and will be used for downstream comparisons of aquatic communities for the 1999 through 2003 sample seasons. The forebay zone, will serve as the downstream station for 1993 through 1995 and 1997 sample seasons. Fish samples consisted of fifteen 300-meter electrofishing runs (approximately 10 minutes duration) and ten experimental gill net sets (five 6.1 meter panels with mesh sizes of 2.5, 5.1, 7.6, 10.2, and 12.7 cm) per station. Attained values for each of the 12 metrics were compared to reference conditions for transition zones of mainstream Tennessee River reservoirs and assigned scores based upon three categories hypothesized to represent relative degrees of degradation: 2

least degraded -5; intermediate -3; and most degraded -1. These categories are based on Wexpected" fish community characteristics in the absence of human-induced impacts other than impoundment. Individual metric scores for a station are summed to obtain the RFAI score. Comparison of the attained RFAI score from the potential impact zone to a predetermined criterion has been suggested as a method useful in identifying presence of normal community structure and function and hence existence of a BIP. For multi-metric indices, two criteria have been suggested to ensure a conservative screening for a BIP. First, if an RFAI score reaches 70 percent of the highest attainable score (adjusted upward to include sample variability), and second; if fewer than half of RFAI metrics potentially influenced by thermal discharge receive a low (1) or moderate (3) score, then normal community structure and function would be present indicating that a BIP existed. Under these conditions, the heated discharge would meet screening criteria and no further evaluation would be needed. The range of RFAI scores possible is from 12 to 60. As discussed in detail below, the average variance for RFAI scores in TVA reservoirs is 6.(+ 3). Therefore, any location that attains an RFAI score of 45 (42 + our sample variance of 3) or higher would be considered to demonstrate a BIP. It must be stressed that scores below this endpoint do not necessarily reflect an adversely impacted fish community. The endpoint is used to serve as a conservative screening level; for example, any fish community that meets these criteria is obviously not adversely impacted. RFAI scQres below this level would require a more in-depth look to determine if a BIP exists. If a score below this criterion is obtained, an inspection of individual RFAI metric results would be

• an initial step to help identify if SQN operation is a contributing factor. This approach is appropriate if a validated niulti-metric index is being used and scoring criteria applicable to the zone. of study.are available.

Upstream/downstream stations comparisons can be used to identify if SQN operation is adversely affecting the downstream fish community as Well. A similar or higher RFAI score at the downstream station compared to the upstream (control) station is used as one basis for determining presence/absence of SQN operational impacts on the resident fish community. Definition of "similar" is integral to accepting the validity of these interpretations.- The Quality Assurance (QA) component of VS monitoring deals with how well the RFAI scores can be repeated and is accomplished by collecting a second.set of samples at 15-20 percent of the stations each year. Experience to date with the QA component of VS shows that the comparison of RFAI index scores from 54 paired sample sets collected over a seven year period ranged from 0 to 18 points, the 7 5th percentile was 6, the 901h percentile was 12. The mean difference between these 54 paired scores is 4.6 points with 95 percent confidence limits of 3.4 and 5.8. Based on these results, a difference of 6 points or less is the value selected for defining "similar" scores between upstream and downstream fish communities. That is, if the downstream RFAI score is within 6 points of the upstream score, the communities will be considered similar. It is important to bear in mind that differences greater than 6 points can be. expected simply due to method variation (25 percent of the QA paired sample sets exceeded that value). When this occurs, a metric-by-metric examination will be conducted to determine what

• caused the difference in-scores and the potential for the difference to be thermally related.

Benthic Macroinvertebrate Community 3

• Ten benthic grab samples were collected at equally spaced points along the upstream and downstream transects. A Ponar sampler was used for most samples but a Peterson sampler was used when heavier substrate was encountered. Collection and processing techniques followed standard VS procedures. Bottom sediments were washed on a 533u screen and organisms were then picked from the screen and remaining substrate and identified to Order or Family level in the field using no magnification. Benthic community results were evaluated using seven community characteristics or metrics. Results for each metric were assigned a rating of 1, 3, or 5 depending upon how they compared to reference conditions developed for VS sample sites. The ratings for the seven metrics were summed to produce a total benthic score for each sample site.

Each reservoir section (inflow, transition, or forebay) differs in their maximum potential for benthic diversity; thus, the criteria for assigning metric ratings were adjusted accordingly such that the total benthic.scores from sites on different reservoir sections are comparable. Potential scores ranged from 7 to 35. Ecological health ratings ("Poor," "Fair,'.' or "Good") are then applied to scores. A similar or higher benthic index score at- the downstream site compared to the upstream site is used as basis for determining if SQN's thermal discharge is having no effect on the Chickamauga Reservoir benthic community. The QA component of VS monitoring shows that the comparison of benthic index scores from 49 paired sample sets collected over a seven year period ranged from 0 to 14 points, the 75h. percentile was 4, the 9 0 th percentile was 6. The mean difference between these 49 paired scores is 3.1 points with 95 percent confidence limits of 2.2 and 4.1. Based on these results, a difference of 4 points or less is the value selected for defining "similar" scores between upstream and downstream benthic communities. That is, if the downstream benthic score is within 4 points of the upstream score, the communities will be considered similar and it will be concluded that SQN has had no effect. Once again, it is, important to bear in mind that differences greater than 4 points can be expected simply due to method variation (25 percent of the QA paired sample sets exceeded that value). When this occurs, a metric-by-metric examination will be conducted to determine what caused the difference in scores and the potential for the difference to be thermally related. Sport Fishing Index Calculations described by Hickman (2000) were used to compare SFI values for selected quantity and quality parameters from creel and population samples to expected values that would occur in a good or high quality fishery. Quantity parameters include angler success and catch per unit effort from standard population samples (electrofishing, trap and experimental gill netting). Population quality is based on measurement of five aspects of each resident sport fish community. Four of these aspects address size structure (proportional number of fish in each length group) of the community, Proportional Stock Density (PSD), Relative Stock Density of Preferred-sized fish (RSDP), Relative Stock Density of Memorable-sized fish (RSDM), and Relative Stock Density of Trophy-sized fish (RSDT) (Figure 1). Relative weight (Wr), a measure of the average condition of individual fish makes up the fifth population quality aspect. As described by Hickman (2000), observed values were compared to reference ranges and assigned a corresponding numerical value. The SFI value is calculated by adding up the scores for quantity and quality from existing data and multiplying by two when only creel or population

• data are available. Species received a low score when insufficient numbers of individuals were.

captured to reliably determine proportional densities or relative weights for particular 4

• parameters. SFI scores are typically compared to average Tennessee Valley reservoir scores; however, Valley-wide scores are unavailable from natural resource agencies. Therefore, Chickamauga Reservoir fish species scores will be compared to previous years.

Snrin2 Sport Fish Survey A SSS was conducted on Chickamauga Reservoir March 24-27, 2003. The summer pool level for Chickamauga is 682.5 msl and, the level during the sample period was measured at 676.4 msl. Twelve sites at three locations including Harrison Bay, Ware Branch and Sale Creek were sampled using boat-mounted electrofishers. TVA Fisheries Biologists use electrofishing equipment to sample fish at selected locations. In that process aný electric current is used to temporarily stun the fish so they float to the surface of the water. The fish are collected with nets, counted, weighed, measured, and released unharmed. Each run consisted of thirty minutes of continuous electrofishing, a total of eighteen hours, in the littoral zones of prominent habitat types represented in the reservoir. Results of the SSS monitoring were calculated using Shoreline Assessment Habitat Index (SAHI), Relative Stock Density (RSD), PSD, and Wr. Habitat type is evaluated using the SAHI metric and is a critical component incorporated into the spring sport fish survey. The resultant habitat designations (good, fair and poor) are correlated to black bass abundance (numbers/hour).

• RSD is the number of fish greater than a minimum preferred length in a stock divided by the number of fish greater than or equal to a minimum stock size.

PSD is the number of fish greater than or equal to a minimum quality length in a sample divided by the number of fish greater than or equal to a minimum stock length. Wr is an index that quantifies fish condition and the preferred range value is 90-105% for moderate density bass populations such as those found in the Tennessee Valley latitudes. Results and Discussion Fish Community In the autumn of 2003, the SQN downstream station scored 45 (Good) and the upstream station scored 42 (Good) using the RFAI analysis methodology (Tables 1 and 2). RFAI scores obtained from VS monitoring stations located upstream and downstream of the SQN discharge over the past several years have revealed consistently good fish community results (Table 3 and Figure 2). Regardless of which downstream station was used, the upstream station rating remained in the "Good" range and the downstream continued in the "Good" range, on average (Table 3 and Figure 2). As indicated in Table 3, between 1993 and 2003, the average RFAI score for the upstream station was 46 (76.6 percent of the maximum score). The two downstream stations (i.e., SQN transition and forebay) both averaged 46 (76.6 percent of the maximum score). Electrofishing and gill netting catch rates for individual species from the downstream station are O listed in Table 4 and 5. Based on the average upstream and downstream RFAI scores, 2003 macroinvertebrate community data, and the defining characteristics for a BIP, it can be 5

• concluded that SQN operati6n has had no impact on the Chickamauga Reservoir resident fish community, on average, for nine sampling seasons (Table 3).

Benthic Macroinvertebrate Community Table 6 provides ratings for each metric as well as the overall benthic index score for both monitoring sites. Table 7 summarizes density by taxon at the upstream (TRM 490.5) and' downstream (TRM 482) collection stations. In the 2003 samnpling season, the upstream station benthic index scores were similar indicative of a BIP. The upstream and downstream comparisons produced benthic index scores of 31 (Good) and 29 (Good), respectively. Therefore, it appears that SQN has had no adverse effect on the benthic macroinvertebrate community immediately downstream from the plant. Table 8 provides benthic index scores from VS monitoring at the forebay (TRM 472.3) and transition zone stations from 1994 to 2003. The Chickamauga forebay zone sample, station is of sufficient distance downstream (11 miles) that results would not be expected to reflect plant effects. The similar scores from TRM 472.3 and TRM 482 also indicate that SQN has had no effect on the macroinvertebrate community immediately downstream from the plant (Table 8). Sport Fishin2 Index In the autumn of 2003' Chickamauga Reservoir's sport fish population received similar SF1 scores compared to the seven year average. Black bass, largemouth bass, smallmouth bass, spotted bass, crappie and white bass received higher scores than their seven year averages (Table 9 and Figure 3). Both sauger and striped bass received lower scores in 2003 compared to scores in 2002. The score for sauger was the lowest it has been since 1997 when this analysis technique was implemented by TVA. This quality assessment is not necessarily indicative of a trend. Historical data indicates that SFI scores typically vary across years. However if future scores would continue to decline, further investigation would be warranted. Channel catfish, crappie and white bass received their highest SFI scores to date. Crappie and white bass scores increased from 38 to 42 and 30 to 40, respectively (Table 9 and Figure 3). Tables 10 and 11 illustrate sport fish index scoring criteria for population metrics and creel quantity and quality. Sauger, striped bass, and channel catfish are easily caught during their spring migration to preferred spawning habitats. Fishing creel surveys conducted in the spring would better describe and evaluate these species compared to only using autumn fisheries surveys. Sprin2 Sport Fish Survey The sampling yielded 1,118 black bass; of these, 65.8% were harvestable size (10" or greater). Of the total black bass collected, 847 were largemouth, 239 were spotted and 32 were smallmouth bass. Overall catch rate (62.0 fish/hr.) was slightly higher than the 2002 survey (57.4/hour) (Table 12). The average weight of harvestable sized black bass was 1.3 pounds. The largest black bass collected were two 6.4 pound largemouth bass taken from Harrison Bay and 6

• Sale Creek. Numbers of lunker bass increased substantially from last year's survey. A total of 23 bass over four pounds were collected and eight of these were over five pounds. In 2002, nine bass over four pounds were collected and four of them were five pounds plus.

Length frequency histograms illustrated a bimodal distribution with the dominant size classes being the 8-9 inch and 12-14 inch groups (Figure 4). A positive correlation of habitat type-to-black bass abundance was evident on Chickamauga Reservoir during the 2003 survey. Among the three areas sampled, the correlations at Harrison Bay and Skull Island were positive but Sale Creek showed some variability among habitat types (Table 13). Overall catch rates for the reservoir *were 78, 66 and 40 at the good, fair and.poor habitats, respectively (Table 14). The RSD and PSD value of 17 and 61 fell within the desirable or preferred ranges of 10-25 and 40-70, respectively (Figures 5 and 6). The values shown in Figure 7 are designated by inch groups which reflect the classical categories, i.e., 0-7 = substock, 8-11 = stock, 12-14 = quality, 15-19 = preferred, 20-24 = memorable and 25+ = trophy. All categories fell within the desired range, which reflects excellent condition of black bass in all size groups of the population. Field observations of large numbers of prey fish indicate an abundance of forage for'all size classes of black bass.

• A total of 288 crappie (249 black and 39 white crappie) were also collected during the survey.

The crappies were collected predominantly from tree tops, stumps and other physical structures in shallow water. 7

• Literature Cited Dycus, D. L. and D. L. Meinert. 1993. Reservoir Monitoring, Monitoring and Evaluation of Aquatic Resource Health and Use Suitability in Tennessee Valley Authority Reservoirs.

Tennessee Valley Authority, Water Resources, Chattanooga, Tennessee, TVA/WM-93/15. Hickman, G. D. 2000. Sport Fish Index (SFI), A Method to Quantify Sport Fishing Quality. Environmental Science & Policy 3 (2000) SI 17-S125. Tennessee Department. of Environment and Conservation. 2000. Draft NPDES Permit Number TN0026450. Tennessee Valley Authority.. 1996. A Supplemental 316(a) Demonstration for Alternative Thermal Discharge Limits for Sequoyah Nuclear Plant, Chickamauga Reservoir, Tennessee. Tennessee Valley Authority, Engineering Laboratory, Norris, TN. WR96-1-45-145. 87 pp. 0 0/ 8

Table 1. Scoring Results for the Twelve Metrics and Overall Reservoir Fish Assemblage Index for Chickamauga Reservoir at the Sequoyah Downstream Sampling Station, 2003. Forebay Trisitlon TRIM 472.3 TRM4S2J) Metric Obs Score A. Species richness and composition

1. Number of species 26 3

2. Number of centrachid 8 5 species

3. Number of benthic 2 1 invertivores

4. Number of intolerant 5 5 species

5. Percent tolerant species electrofishing 55.6 1.5 gill netting 27 1.5

6. Percent dominance by electrofishing 29.9 1.5 one species gill netting 21.4 1.5 I 7. Number non-native electrofishing 1.0 2.5 species gill netting 0.5 2.5

8. Number of top 10 5 carnivore species B. Trophic composition

9. Percent top carnivores electrofishing 9.5 1.5 gill netting 49.5 1.5

10. Percent omnivores electrofishing 11.2 2.5 gill netting. 35.2 0.5 C. Fish abundance and health

11. Average number per electrofishing 32.1 0.5 run gill netting 19.6 1.5

12. Percent anomalies electrofishing 0.8 2.5 gill netting 0.5 2.5 RFAI 43 Good 0

9

Table 2. Scoring Results for the Twelve Metrics and Overall Reservoir Fish Assemblage Index for Chickamauga Reservoir at the Upstream Sampling Station, 2003.

                                                    -                                   Inflow
                                                .......                   .....       TRM 529.0 Metric                                                              Obs           Score A. Species richness and composition

1. Number of species 30 5

2. Number of centrachid 8 5 species

3. Number of benthic 5 3 invertivores

4. Number of intolerant 5 5 species

5. Percent tolerant species electrofishing 57.7 3 gill netting 0 0

6. Percent dominance by electrofishing 34.2 3 one species gill netting 0.0 0 0.6 5

7. Number non-native electrofishing species gill netting 0 0

8. Number of top 10 5 carnivore species B. Trophic composition

9. Percent top carnivores electrofishing 10.2 1 gill netting 0 0

10. Percent ornnivores electrofishing 18.7 5 gill netting 0 3 C. Fish abundance and health

11. Average number per electrofishing 69.1 3 run gill netting 0 0

12. Percent anomalies electrofishing 0.7 5 gill netting 0 0 RFAI 48 Good 0

10

Table 3. Recent (1993-2003) RFAI Scores Collected as Part of the Vital Signs Monitoring Program Upstream and Downstream 0 of Sequoyah Nuclear Plant. Station Reservoir Location 1993 1994 1995 1997 1999 2000* 2001 2002* 2003 Upstream Chickamauga TRM 49 40 46 39 45 46 45 51 42 490.5 Sequoyah Chickamauga TRM 41 48 46 43 45 Transition 482.0 Forebay Chickamauga TRM 44 44 47 39 45 45 48 46 43 1_ 1__472.3 1

• The 2000, and 2002, sample years were not part of the VS monitoring program, however the same methodology was applied.

11

 £         Table 4. Species Listing and Catch Per Unit Effort for the Embayment and Sequoyah Transects During the Fall Electrofishing and Gill Netting on Chickamauga Reservoir, 2003 (Electrofishing Effort = 300 Meters of Shoreline and Gill Netting Effort = Net-Nights).

Forebay TRM 472.3 Transition TRM 482.0 Electrofishing Electrofishing Gill Netting Electrofishing Electrofishing Gill Netting Catch Rate Catch Rate Catch Rate Catch Rate Catch Rate Catch Rate Common Per Per Hour Per Per Per Hour Per Name Run Net Night Run Net Night Q,- , +4, OjJJtLL*~U *,a1 ( 1 '7 U.Z. I 1 A" I ."1J - fA' 1)

                                                                         '.Z.U 1 FlQ I 'JO         -

Longnose gar - - 0.10 Skipjack herring - 3.30 - 0.70 Gizzard shad 2.73 14.70 4.20 8.40 45.32 2.90 Threadfin shad 0.20 1.08 0.10 - - - Common carp 0.33 1.79 - 0.13 0.72 0.10 Golden shiner 0.53 2.87 0.10 0.40 2.16 0.10 Emerald shiner 6.33 34.05 - 6.20 33.45 - Spotfin shiner 0.13 0.72 - 1.33 7.19 - Spotted sucker 0.20 1.08 0.60 0.27 1.44 0.50 Blue catfish - 1.60 - - 1.20 Channel catfish - - 1.00 0.40 2.16 1.50 ,,,lathead catfish 0.33 1.79 0.20 0.13 0.72 0.30 ite bass - - 0.10 - - - Yellow bass 0.07 0.36 2.40 0.13 0.72 1.80 Warmouth 0.27 1.43 - Redbreast 3.33 17.92 1.93 10.43 Green sunfish 0.27 1.43 Bluegill 9.60 . 51.61 0.70 11.33 61.15 0.40 Longear sunfish 0.40 2.15 - 1.93 10.43 - Redear sunfish 3.67 19.71 1.00 6.40 34.53 1.60 Hybrid sunfish 0.07 0.36 - - - Smallmouth 0.20 1.08 0.10 0.13 0.72 1.20 Spotted bass 1.27 6.81 2.50 2.80 15.11 0.80 Largemouth 0.93 5.02 0.20 1.47 7.91 0.20 White crappie - - 0.10 .- 0.10 Black crappie - - 0.80 0.27 1.44 0.10 Yellow perch - - 0.10 - - Logperch - - - 0.60 3.24 - Sauger - - 0.20 Freshwater 0.27 1.43 0.50 0.33 1.80 1.00 Brook silverside 0.73 3.94 -- - Total 32.13 172.76 19.6 45.71 246.76 14.8 Number 15 10 15 10

• kumber 482 196 686 148 Wpecies 22 19 20 19 12

£ Table 5. Species Listing and Catch Per Unit Effort for the Transition and Inflow Transects During the Fall Electrofishing and Gill Netting on Chickamauga Reservoir, 2003 (Electrofishing Effort = 300 Meters of Shoreline and Gill Netting Effort = Net-Nights). Transition TRM 490.5 Inflow TRM 529.0 Electrofishing Electrofishing Gill Netting Electrofishing Electrofishing Catch Rate Catch Rate Catch Rate Catch Rate Catch Rate Common Name Per Per Per Per Per Run Hour Net Night Run Hour Longnose gar - -0.20 1.08 Lake sturgeon 0.10 -1.08 0.20 Spotted gar 0.07 0.34 Skipjack herring 2.10 Gizzard shad 5.60 28.38 7.00 11.87 63.8 Threadfin shad 1.13 5.74 0.10 17.67 94.98 Common carp 0.4 2.03 0.40 2.15 Golden shiner 1.67 8.45 0.20 1.08 Emerald shiner 1.00 5.07 0.20 1.08 Spotfin shiner 1.27 6.42 0.73 3.94 Steelcolor shiner 0.27 1.43 Bluntnose minnow 0.80 4.05 0.13 0.72 Spotted sucker 0.40 2.03 0.30 0.27 1.43 Black redhorse 0.40 2.15 Golden redhorse 0.40 2.15 Blue catfish 2.60 Channel catfish 0.13 0.68 1.40 0.33 1.79 Flathead catfish 0.33 1.69 0.40 0.33 1.79 White bass 0.13 0.72 Yellow bass 3.30 1.13 6.09 Warmouth 0.93 4.73 0.07 0.36 Redbreast sunfish 3.87 19.59 0.47 2.51 Green sunfish 0.20 L01 0.20 1.08 Bluegill 12.87 65.2 23.60 126.88 Longear sunfish 1.80 9.12 0.20 1.08 Redear sunfish 3.00 15.2 4.70 4.07 21.86 Hybrid sunfish 0.13 0.72 Smallmouth bass 0.80 4.05 0.67 3.58 Spotted bass 1.40 7.09 0.70 1.60 8.60 Largemouth bass 1.00 5.07 0.30 2.00 10.75 White crappie 0.10 0.07 0.36 Black crappie 1.27 6.42 0.80 0.87 4.66 Yellow perch, 0.07 0.34 0.20 13

0 Table 5. (continued) Transition TRM 490.5 Inflow TRM 529.0 Electrofishing Electrofishing Gill Netting Electrofishing Electrofishing Catch Rate Catch Rate Catch Rate Catch Rate Catch Rate Common Name Per Per Per Per Per Run Hour Net Night Run Hour Logperch 0.27 1.35 - 0.07 0.36 Sauger - 0.10 Walleye - 0.07 0.36 Freshwater drum 0.33 1.69 0.70 0.20 1.08 Brook silverside 0.67 3.38 - 0.13 0.72 Total 41.28 209.12 24.9 69.08 371.34 Number Samples 15 10 15 Number Collected 619 249 1036 Species Collected 25 17 32 0 14

• Table 6. Individual Metric Ratings and the Overall Benthic Community Index Score for Upstream and Downstream Stations near Sequoyah Nuclear Plant, Chickamauga Reservoir, November 2003.

TRM 490.5 TRM 482 Upstream Downstream Metric Obs Ratin Rating

1. Average number of taxa 7.4 5 5.7 5

2. Proportion of samples with long-lived organisms 90% 5 60% 3

3. Average number of EPT taxa 0.7 3 0.3 1

4. Average proportion of oligochaete individuals 10.7% 5 9.4% 5

5. Average proportion of total abundance comprised by the 71.0% 5 79.8% 5

• two most abundant taxa

6. Average density excluding chironomids and 341.7 3 580.0 5 oligochaetes Zero-samples - proportion of samples containing no 0 5 0 5 organisms Benthic Index Score 31 29 Good Good

 *Scored with transition criteria.

15

Table 7. Average Mean Density Per Square Meter of Benthic Taxa Collected at Upstream and Downstream Stations near Sequoyah Nuclear Plant, Chickamauga Reservoir, November 2003. TRM Chickamauga Reservoir 490.5 Upstream Mean Occurrence Species Density per site Phylum Annelida Subclass Oligocheata Family Tubificidae 120 8 Branchiurasowerbyi 2 1 Limnodrilus hoffineisteri 30 6 Class flirudinea Rhynchobdellida Family Glossiphoniidae 5 1 Helobdella stagnalis 18 4 Phylum Insecta Order Ephemeroptera Family Ephemeridae Hexagenia limbata <10rmm 17 6 Hexagenia limbata >10rnm 32 8 Order Trichoptera Family Polycentropodidae Polycentropussp. 2 1 Family ' Leptoceridae Oecetis sp. 2 1 Order Diptera Family Chironomidae Ablabesmyia annulata 8 3 Chironomussp. ,10 5 Phylum Mollusca Class Gastropoda Order Mesogastropoda Family Viviparidae Campeloma sp. 2 Viviparus Georgianus 33. 4 Viviparussp. 18 3 Class Bivalvia Veneroida Family Corbiculidae Corbiculafluminea<10rmm 38 7 Corbiculafluminea>10rmm 93 8 16

• Table 7. (continued)

TRM Chickamauga Reservoir 490.5 Upstream Mean Occurrence Species Density per site Family Sphaeriidae Musculiurn transversum 80 7 Number of samples 10 Sum 862 Number of taxa 15 Number of EPT taxa 3 Sum of area sampled 0.6 TRM Chickamauga Reservoir 482 Downstream Mean Occurrence Species Density per site Nematoda Turbellaria Tnrcladida Planariidae Dugesiatigrina 2 1 Phylum Annelida Subclass Oligocheata Family Lumbricidae 2 1 Family Tubificidae 42 5 Limnodrilus hoffineisteri 13 5 Class Hirudinea 2 1 Rhynchobdellida Family Glossiphoniidae 2 1 Helobdella stagnalis 20 5 Pharyngobdellida Family Erpobdellidae 7 1 Crustacea Amphipoda Crangonyctidae Crangonyx sp. 2 1 Phylum Insecta Order Ephemeroptera Family Ephemeridae 17

• Table 7. (continued)

TRM Chickamauga Reservoir 482 Downstream Mean Occurrence Species Density per site Hexagenia limbata <10mm 5 .2 Hexagenia limbata >I0rmm 25 3 Order Trichoptera Family Polycentropodidae Cyrnellus fraternus 8 3 Order Diptera Family Chironomidae Ablabesmyia annulata 10 4 Axarus sp. 2 1 Chironomussp. 7 3 Coelotanypus sp. 127 8 Phylum Mollusca Class Gastropoda Lymnophila Family Physidae Physella sp. 2 1 Order Mesogastropoda Family Viviparidae Viviparus Georgianus 62 3 Class Bivalvia Veneroida Family Corbiculidae Corbiculafluminea <10mm 195 9 Corbiculafluminea>10mm 98 9 Family Sphaeriidae Euperacubensis 3 1 Musculium transversum 200 10 Number of samples 10 Sum 833 Number of taxa 18 Number of EPT taxa 2 Sum of area sampled 0.6 0

                                            '18

Table 8. Recent (1994-2003) Benthic Index Scores Collected as Part of the Vital Signs Monitoring Program at Chickamauga Reservoir Transition (TRM 490.5 and TRM 482) and Forebay Zone (TRM 472.3) Stations. Year Site Reservoir Location 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 Average Upstream Chickamauga TRM 490.5 33 29 31 31 23 25 23 31 28.3 Downstream Chickamauga TRM 482 23 31 27 29 28.0 Downstream Chickamauga TRM 472.3 31 27 29 25 27 27 23 27 27.0

                                      -A Table 9. Sport Fishing Index Results for Chickamauga Reservoir, 2003 Year Species          1997       1998      1999       2000        2001        2002       2003       1997-2003 Average SF1 Score Black bass             35         41        25         35           31          34         34           34 Smallmouth bass        20         20        24         22           40          32         32           28 Spotted bass           20         37        24         40           26          32         32           30 Largemouth bass        34         37        34         32           28          36         36           34 Bluegill               30                   32         33           32          32         31           32 Channel catfish                             32         29           30          25         33           35 Crappie                32                   31         31           32          38         42           35 Sauger                 27         36        32         39           30          31         27           32 Striped bass           35                   30         30           40          34         31           33 White bass                                  31         30           30         .30         40           32 19

0 Table 10. Sport Fishing Index Population Quantity and Creel Quantity and Quality Metrics and Scoring Criteria. Metrics Scores 5 10 15 Black bass Population (quantity) TVA electrofishing catch/hour <15 .15-31 >31 State electrofishing (catch/hour) <62 62-124 > 124 Creel (quantity)a Anglers (catch/hour) <0.3 0.3-0.6 >.0.6 BAIT and BITE data <1.1 1.1-2.3 > 2.3 Creel (quality) Pressure (hours/acre) <8 8-16 > 16 Largemouth bass Population (quantity)b TVA electrofishing catch/hour <13 13-25 > 25 State electrofishing (catch/hour)

• 53 53-106 > 106 Creel (quantity)

Anglers (catch/hour) < 0.29 0.29-0.58 > 0.58

• Creel (quality)

Pressure (hours/acre) <8 8-16 > 16 Smallmouth bass Population (quantity) TVA electrofishing catch/hour <4 4-8 >8 State electrofishing (catch/hour) <8 8-15 > 15 Creel (quantity) Anglers (catch/hour) <0.1 0.1-0.3 > 0.3 Creel (quality) Pressure (hours/acre) <8 8-16 >16. Spotted bass Population (quantity) TVA electrofishing catch/hour <5 5-11 >11 State electrofishing (catch/hour) <14 14-27 > 27 Creel (quantity) Anglers (catch/hour) < 0.07 0.07-0.13 >0.13 Creel (quality) Pressure (hours/acre) <8 8-16 > 16 0 20

Table 10. (continued) Metrics Scores 5 10 15 Sauger Population (quantity) Experimental gill net (catch/net night) <9 9-17 > 17 Creel (quantity) Anglers (catch/hour) < 0.5 0.5-1 > I Creel (quality) Pressure (hours/acre) <5 5-10 > 10 Channel catfish Population (quantity) Experimental gill net (catch/net night) <2 2-4 >4 Creel (quantity) Anglers (catch/hour). < 0.3 0.3-0.7 > 0.7 Creel (quality) Pressure (hours/acre) <9 9-19 > 19 aEach worth 2.5, 5.0, and 7.5 points if both data sets are available. bTVA electrofishing only used when state agency electrofishing data is unavailable. 21

0 Table 11. Sport Fishing Index Population Quality Metrics and Scoring Criteria. Scores 5 10 15 Metrics Population (quality) 1 2 3 PSD < 20 or > 80 20-39 or 61-80 40-60 RSDP (preferred) 0 or> 60 1-9 or 41-60 10-40 RSDM (memorable) 0 or > 25 1-4 or 11-25 5-10 RSDT (trophy) 0 <1 1> W, (Stock-preferred size fish) < 90 > 110 90-110 Table 12. Electrofishing Catch Rate, Mean Weight, Percent Harvestable, Numbers of Black Bass Greater than Five Pounds, Numbers of Black Bass Greater than Four Pounds and Largest Black Bass Collected, Chickamauga ReservoirBlack Bass Surveys, 1995-2003. EF Catch Mean Largest Yea Rate Weight  % Bass >4 Bass >5 bass r (no./hr.) (lbs.) Harvestable lbs. lbs. (lbs.) 2003 62.0 1.3 65.8 23 8 6.4 2002 57.4 1.1 59.4 9 4 6.6 2001 34.5 0.8 45.2 0 0 2.8 2000 34.4 1 51.2 3 0 4.8 1999 10.6 1.3 60.7 3 1 6.1 1998 37.2 1.1 44.5 9. 2 6.6 1997 40.2 1 70.1 8 4 8.7 1996 51 1.2 42.6 13 9 7.9 1995 62 1.2 61.8 28 12 8.3 22

Table 13. Black Bass Catch Per Hour Compared to Habitat Types by Location. 0 H~Ihit2t f)P~wn2tinn Reservoir and Site Good Fair Poor Chickam auga Harrison Bay 99(4) 61(4) 31(4) Sale Creek 67(4) 76(4) 36(4) Skull Island 69(4) 63(5) 58(3) Watts Bar Blue Springs 69(3) 47(4) 46(5) Caney Creek 78(3) 61(5) 49(4) Kingston 59(4) 43(4) 43 (4) Watts Bar Dam 107(3) 43(5) 62(4) Catch per hour = number of fish collected per hour ( ) = number of transects sampled at each location Table 14. Black Bass Catch Per Hour Compared to Habitat Types by Reservoir. HABITAT DESIGNATION Reservoir Good Fair Poor Chickamauga 78 66 40 Watts Bar 77 49 50 Wheeler 57 54 5.6 Catch per hour = number of fish collected per hour 0 23

Quantity Parameters Quality Parameters Figure 1. Parameters used to calculate the Sport Fishing Index (SFI). 0 24

Chickamauga RFAI Scores 1993-2003 60 50 40 I.I.

      ~30 20 10 0

1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 Year Figure 2. RFAI scores from sample years between 1993 and 2003. 25

0 Chickamauga SF1 Scores 1997-2003 60 50 E3 Black bass 40 MLargemnouth bass O Smalmouth bass O Spotted bass ... 0 MCrappie 30

Sauger- '.. "

U,)

                                                                                                . Striped bass'.

0 Blu*egill 20 E Channel catfish MWhite bass 10 0 1997 1998 1999 2000 2001 2002 2003 Year Figure 3. Sport Fishing Index results for Chickamauga Reservoir between 1997 and 2003. 26

0 ~LEN\ýGTH FREQUENCY

                                         -ALL SITES
                                   ý:CHICKAMAUGA 2003 180 160 140 S120 100T                           87 1:!!::!!:!!:!2                        !::!!!            .: :::o

:2.!/ ::!: o!!!

S80 Z 60 4 42 40 20 1 0 t 35 7 9 11 13 15 17 19 21 23 25 INCH GROUP Figure 4. Chickamauga Reservoir length frequency histogram, (all sites) spring 2003. 27

RSD VALUES MAINSTEM RESERVOIRS SPRING 2003 50 45 40 35 30 - 28

                                * /1 c 25-C.)

20 17 / 18l 15 62 150 Desirable RSD 15 Range -*12 59 0 C) ~ 'I * ~z -0 -0 C: CD CD E. F), Do-C) a 0 CD CD rz 0 C A CD 0 1<C DC CD Reservoir Figure 5. Relative stock density values for Tennessee River Reservoirs. 0 28

0 PSID VALUES MANSTEM RESERVOIRS SPRING 2003 Ann . +.- .+.. 90-80-70 66)ý-6 614 S60-

50. Desirable PSO Range 4 40- --------

30-20 10-0 C*<) z -U

                               '1!~i                  CD      'D:

F; a --'n 1 ID

3) CO D: 0l.

                              ,. -.          *Lfli            0-'      Di        a CD:

0:¸i a<, Reservoir Figure 6. Proportional stock density values for Tennessee River Reservoirs. 0 29

0 CHICKAMAUGA Wr ALL SITES 2003 I= Percent -.-- # of Fish I 45 40

                                                                         .35 LL 30 25  0 a)                                                                20 U

I..

0) 15 E 0~

                                                                         *10 5

0 0I Figure 7. Chickamauga Reservoir mean relative weights (Wr) for largemouth bass broken out by RSD category and fish numbers. 0 30

Biological Monitoring of the Tennessee River Near Sequoyah Nuclear Plant Discharge 2004 by Dennis S. Baxter Donny R. Lowery June 2005 Final Aquatic Monitoring and Management Knoxville, Tennessee 0

Table of Contents Page Introduction I Methods 2 Fish Community 2 Benthic Macroinvertebrate Community 4 Sport Fishing Index 4 Spring Sport Fish Survey 5 Results and Discussion 5 Fish Community 5 Benthic Macroinvertebrate Community 6 Sport Fishing Index 6 Spring Sport Fish Survey 6 Literature Cited 8 List of Tables Table 1. Scoring Results for the Twelve Metrics and Overall Reservoir Fish Assemblage Index for Chickamauga Reservoir at the Sequoyah Downstream Sampling Station, 2004. 9 -Table2. Scoring Results for the Twelve Metrics and Overall Reservoir Fish Assemblage Index for Chickamauga Reservoir at the Upstream Sampling Station, 2004. 10 Table 3. Recent (1993-2004) RFAI Scores -Collected as Part of the Vital Signs Monitoring Program Upstream and Downstream of Sequoyah Nuclear Plant. 11 Table 4. Species Listing and Catch Per Unit Effort for the Embayment and Sequoyah Transects During the Fall Electrofishing and Gill Netting on Chickamauga Reservoir, 2004 (Electrofishing Effort = 300 Meters of Shoreline and Gill Netting Effort = 10 Net-Nights). 12 Table 5. Species Listing and Catch Per Unit Effort for the Transition and Inflow Transects During the Fall Electrofishing and Gill Netting on Chickamauga Reservoir, 2004 (Electrofishing Effort = 300 Meters of Shoreline and Gill Netting Effort 10 Net-Nights). 13 i

List of Tables (continued) Pa e Table 6. Individual Metric Ratings and the Overall Benthic Community Index Score for Upstream and Downstream Stations near Sequoyah Nuclear Plant, Chickamauga Reservoir, November 2004. 15 Table 7.. Average Mean Density Per Square Meter of Benthic Taxa Collected at Upstream and Downstream Stations near Sequoyah Nuclear Plant, Chickamauga Reservoir, November 2004. 16 Table 8. Recent (1994-2004) Benthic Index Scores Collected as Part of the Vital Signs Monitoring Program at Chickamauga Reservoir Transition (TRM 490.5 and TRM 482) and Forebay Zone (TRM 472.3) Stations. 19 Table 9. Sport Fishing Index Results for Chickamauga Reservoir, 2003. 19 Table 10. Sport Fishing Index Population Quantity and Creel Quantity and Quality Metrics and Scoring Criteria. 20 Table 11. Sport Fishing Index Population Quality Metrics and Scoring Criteria. 22 Table 12. Electrofishing Catch Rate, Mean Weight, Percent Harvestable, Numbers. of Black Bass Greater than Five Pounds, Numbers of Black Bass Greater than Four Pounds and Largest Black Bass Collected, Chickamauga Reservoir Black Bass Surveys, 1995-2004. 22 Table 13. Black Bass Catch Per Hour Compared to Habitat Types by Location. 23 Table 14. Black Bass Catch Per Hour Compared to Habitat Types by Reservoir. 23 List of Figures Figure 1. Parameters used to calculate the Sport Fishing Index (SFI). 24 Figure 2. RFAI scores from sample years between 1993 and 2004. 25 Figure 3. Sport Fishing Index results for Chickamauga Reservoir between 1997 and 2003. 26 Figure 4. Chickamauga Reservoir length frequency histogram, (all sites) spring 2004. 27 0 Figure 5. Relative stock density values .for Tennessee River Reservoirs. 28 ii

List of Figures

                                       -(continued)

Page Figure 6. Proportional stock density values .for Tennessee River Reservoirs. 28 Figure 7. Chickamauga Reservoir mean relative weights. (Wr) for largemouth bass broken out by RSD category and fish numbers. 28 Acronyms BI Benthic Macroinvertebrate Index BIP Balanced Indigenous Population NPDES National Pollutant Discharge Elimination System PSD Proportional Stock Density QA Quality Assurance RFAI Reservoir Fish Assemblage Index RSD Relative Stock Density RSDM Relative Stock Density of Memorable-sized RSDP Relative Stock Density of Preferred-sized . RSDT Relative Stock Density of Trophy-sized SAHI Shoreline Assessment Habitat'Index SFI Sport Fishing Index' SQN Sequoyah Nuclear Plant SSS Spring Sport Fish Survey TRM Tennessee River Mile TVA Tennessee Valley Authority VS Vital Signs Wr Relative Weight iii

Introduction Section 316(a) of the Clean Water Act specifies that industrial, municipal, andother facilities must obtain permits if their discharges go directly to surface waters. Industries responsible for point-source dischargers of heated water can obtain a variance from state water quality standards if the industry can demonstrate compliance with thermal criteria by documenting the maintenance of Balanced Indigenous Populations (BIP) of aquatic life in the vicinity of its discharge. Sequoyah Nuclear Plant's (SQN) current National Pollutant Discharge Elimination System (NPDES) permit number TN0026450 states, "For Section 316(a), the permittee shall. summarize previous data and indicate whether significant changes have occurred in plant operation, reservoir operations or in stream biology that would necessitate that significant changes to the permitted variance." The permittee shall use the Reservoir Fish Assemblage Index (RFAI) to assess Chickamauga Reservoir fish community health. Any apparent declines in the fish community health will be further investigated to discover whether the decline is a valid conclusion and if the decline is real to identify possible sources for the fish community decline. As part of the identification of potential sources for the decline, the instream effects of the discharges made under this permit will be investigated (TDEC 2000). In response to this requirement, Tennessee Valley Authority's (TVA's) Vital Signs (VS) monitoring program (Dycus and Meinert 1993) will be used to evaluate areas of Chickamauga Reservoir upstream and downstream of SQN discharge. The purpose of this document is to briefly summarize and provide the Tennessee Department of Environment and .Conservation results of comparisons between current and historical monitoring data. Prior to 1990, TVA focused on reservoir ecological assessments to meet specific needs as they arose. In 1990, TVA instituted a Valley-wide VS monitoring program which is a broad-based evaluation of the overall ecological conditions in major reservoirs. Data is evaluated with a multi-metric monitoring Approach utilizing five environmental indicators: dissolved oxygen, chlorophyll, sediment quality, benthic macroinvertebrate community, and the fish community. Wheh this program was initiated, specific evaluation techniques were developed for each indicator, and these techniques were fine-tuned to better represent ecological conditions. The outcome of this effort was development of multi-metric evaluation techniques for the fish assemblage (i.e., RFAI) and the benthic community, as described below. These multi-metric evaluation techniques have proven successful in TVA's monitoring efforts as well as other federal and state monitoring programs. Therefore, they will form the basis of evaluating these monitoring results. For consistency, only RFAI analyses between 1993 and 2004 will be utilized. The Benthic Macroinvertebrate Index (BI) is used primarily to support the RFAI analysis. In thepast, the Sport Fishing Index (SFI) was used.in support of a thermal variance request at SQN (TVA 1.996). The SFI was developed to quantify sport fishing quality for individual sport fish species. The SFI provides biologists with a reference point to measure the quality of a sport fishery. Comparison of the population sampling parameters and creel results for a particular sport fish species with expectations of these parameters from a high quality fishery (reference conditions) allows for the determination of fishing quality. Indices have been developed for I

black bass (largemouth, smallmouth and spotted bass), sauger, striped bass, bluegill, and channel

• catfish. Each SFI relies on measurements of quantity and quality aspects of angler success and fish population characteristics.

In recent years, SF1 information has been used to describe the quality of the resident fishery in conjunction with compliance monitoring, thermal variance requests, and other regulatory issues at TVA nuclear plants in Tennessee. Similar NPDES compliance monitoring programs usirng the methodologies described above are also being performed at Browns Ferry Nuclear, Colbert and Widows Creek Fossil Plants in Alabama. The TVA Spring Sport Fish Survey (SSS) is conducted to evaluate the sport fish population of TVA Reservoirs. The results of the survey are used by state agencies to protect, improve and assess the quality of sport fisheries. Predominant habitat types in the reservoir are surveyed to determine sport fish abundance. In addition to accommodating TVA and state databases, this surveying method aligns with TVA Watershed Team and TVA's Reservoir Operations Study objectives. Sample sites are selected using the shoreline habitat characteristics employed by the Watershed Teams. The survey predominantly targets three species of black bass (largemouth, smallmouth, and spotted bass) and black and white crappie. These species are the predominant sport fish sought after by fisherman. Methods

• 'Fish Community Reservoirs are typically divided into three zones for VS Monitoring - inflow, transition and forebay. The inflow zone is generally in the upper reaches of the reservoir and is rivenine in nature; the transition zone or mid-reservoir is the area where water velocity decreases due to.

increased cross-sectional area, and the forebay.is the lacustrine area near the dam. The Chickamauga Reservoir inflow zone sample site is located at Tennessee River Mile (TRM) 529.0; the transition zone sampling site is located at TRM 490.5 and the forebay zone sampling. site is located at TRM 472.3. The VS transition zone, which is located approximately 7.2 river miles upstream of the SQN discharge (TRM 483.3), will be used to provide upstream data for the 316(a) thermal variance studies performed in sample years between 1993 and 2004. An

 *additional transition station was later added downstream of the SQN discharge to more closely.

monitor Chickamauga Reservoir aquatic communities in close proximity to the SQN thermal effluent. This station is located at TRM 482.0 and will be used for downstream comparisons of aquatic communities for the 1999 through 2004 sample seasons. The forebay zone, will serve as the downstream station for 1993 through 1995. and 1997 sample seasons. Fish samples consisted of fifteen 300-meter electrofishing runs (approximately 10 minutes duration) and ten experimental gill net sets (five 6.1 meter panels with mesh sizes of 2.5, 5.1, 7.6, 10.2, and 12.7 cm) per station. Attained values for each of the 12 metrics were.compared to reference conditions for transition zones of mainstream Tennessee River reservoirs and assigned scores based upon three categories hypothesized to represent relative degrees of degradation: 2

least degraded -5; intermediate -3; and most degraded -1. These categories are based on

• "expected" fish community characteristics in the absence of human-induced impacts other than impoundment. Individual metric scores for a station are summed to obtain the RFAI score.

Comparison of the attained RFAI score from the potential impact zone to a predetermined criterion has been suggested as a method: useful in identifying presence of normal community structure and function and hence existence of a BIP. For multi-metric indices, two criteria have been suggested to ensure a conservative screening for a BIP. First, if an RFAI score reaches 70 percent of the highest attainable score (adjusted upward to include sample variability), and second, if fewer than half of RFAI metrics potentially influenced by thermal discharge receive a low (1) or moderate (3) score, then normal community structure and function would be present indicating that a BIP existed. Underthese conditions, the heated discharge would meet screening criteria and no further evaluation would be needed. The range of RFAI scores possible is from 12 to 60. As discussed in detail below, the average variance for RFAI scores in TVA reservoirs is 6 (+/- 3). Therefore, any location that attains an RFAI score of 45 (42 + our sample variance of 3) or higher would be considered to demonstrate a BIP. It must be stressed that scores below this endpoint do not necessarily reflect an adversely impacted fish community. The endpoint is used to serve as a conservative screening level; for example, any fish community that meets these criteria is obviously not adversely impacted. RFAI scores below this level would require a more in-depth look to determine if a BIP exists. If a score below this criterion is obtained, an inspection of individual RFAI metric results would be an initial step to help identify if SQN operation is a contributing factor. This approach is appropriate if a validated multi-metric index is being used and scoring criteria applicable to the zone of study are available. Upstream/downstream stations comparisons can be used to identify if SQN operation is adversely affecting the downstream fish community as well. A similar or higher RFAI score at the downstream station compared to the upstream (control) station is used as one basis for determining presence/absence of SQN operational impacts on the resident fish community. Definition of "similar" is integral to accepting the validity of these interpretations. The Quality Assurance (QA) component of VS monitoring deals with how well the RFAI scores can be repeated and is accomplished by collecting a second set of samples at 15-20 percent of the stations each year. Experience to date with the QA component of VS shows that the comparison of RFAI index scores from 54 paired sample sets collected over a seven year period ranged from 0 to 18 points, the 7 5 th percentile was 6, the 90'b percentile was 12. The mean difference between these 54 paired scores is 4.6 points with 95 percent confidence limits of 3.4 and 5.8. Based on these results, a difference of 6 points or less is the value selected for defining "similar" scores between upstream and downstream fish communities. That is, if the downstream RFAI score is within 6 points of the upstream score, the communities will be considered similar. It is important to bear in mind that differences greater than 6 points can be expected simply due to method variation (25 percent of the QA paired sample sets exceeded that Value). When this occurs, a metric-by-metric examination will be conducted to determine what caused the difference in scores and the potential for the difference to be thermally related. SBenthic Macroinvertebrate Community 3

Ten benthic grab samples were collected at equally spaced points along the upstream and

• downstream transects. A Ponar sampler was used for most samples but a Peterson sampler was used when heavier substrate was encountered. Collection and processing techniques followed standard VS procedures. Bottom sediments. were washed on a 533 t screen and organisms were then picked from the screen and remaining substrate and identified to Order or Family level in the field using no magnification. Benthic community results were evaluated using seven community characteristics or metrics. Results for each metric were assigned a rating of 1, 3, or 5 depending upon how they compared to reference conditions developed for VS sample sites. The ratings for the seven metrics were summed to produce a total benthic score for each sample site.

Each reservoir section (inflow, transition, or forebay) differs in their maximum potential for benthic diversity; thus, the criteria for assigning metric ratings were adjusted accordingly such that the total benthic scores from sites on different reservoir sections are comparable. Potential scores ranged from 7 to 35. Ecological'health ratings ("Poor," "Fair," or "Good") are then applied~to scores. A similar or higher benthic index score at the downstream site compared to the upstream site is used as basis for determining if SQN's thermal discharge is having no effect on the Chickamauga Reservoir benthic community. The QA component of VS monitoring shows that the comparison of benthic index scores-from 49 paired sample sets collected over a seven year period ranged from 0 to 14 points, the 75th percentile was 4, the 90th percentile was 6. The mean difference between these 49 paired scores is 3.1 points with 95 percent confidence limits of 2.2 and 4.1. Based on these results, a difference of 4 points or less is the value Selected for defining "similar" scores between upstream and downstream benthic communities. That is, if the downstream benthic score is within 4

• points of the upstream score, the communities will be considered similar and it will be concluded that SQN has had no effect. Once again, it is important to bear in mind that differences greater than 4 points can be expected simply due to method variation (25 percent of the QA paired sample sets exceeded that value). When this occurs, a metric-by-metric examination will be conducted to determine what caused the difference in scores and the potential for the difference to be thermally related.

Sport Fishina Index Calculations described by Hickman (2000) were used to compare SFI values for selected quantity and quality parameters from creel and population samples to expected values that would occur in a good or high quality fishery. Quantity parameters include angler success and catch per unit effort from standard population samples (electrofishing, trap and experimental gill netting). Population quality is based on measurement of five aspects of each resident sport fish community. Four of these aspects address size structure (proportional number of fish in each length group) of the community, Proportional Stock Density (PSD), Relative Stock Density of Preferred-sized fish (RSDP), Relative Stock Density of Memorable-sized fish (RSDM), and Relative Stock Density of Trophy-sized fish (RSDT) (Figure 1). Relative weight (Wr), a measure of the average condition of individual fish makes up the fifth population quality aspect. As described by Hickman (2000), observed values were compared to reference ranges and assigned a corresponding numerical value. The SFI value is calculated by adding the scores for quantity and quality from existing data and multiplying by two when only creel or population data are available. Species received a low score when insufficient numbers of individuals were

• • captured to reliably determine proportional densities or relative weights for particular 4

parameters. SFI scores are typically compared to average Tennessee Valley reservoir scores;

• however, Valley-wide scores are unavailable from natural resource agencies. Therefore, Chickamauga Reservoir fish, species scores will be compared to previous years. The 2004 State Fisheries gill netting and creel data were not available for analysis before-this report was submitted; therefore 2003 SFI data were used for analysis.

Sprin2 Sport Fish Survey A spring sportfish survey was conducted on Chickamauga Reservoir March 2004. Twelve sites at three locations including Harrison Bay, Ware Branch and Sale Creek were sampled using boat-mounted electrofishers. Each run consisted of thirty minutes of continuous electrofishing in the littoral zones of prominent habitat types represented in the reservoir. Summer pool level for Chickamauga is 682.5 msl and sampling was conductedat 676.6 msl. TVA Fisheries Biologists use electrofishing equipment to sample fish at selected locations. In that process an electric current is used to temporarily stun the fish so they float to the surface of the water. The fish are collected with nets, counted, weighed, measured, and released unharmed. Each run consisted of thirty minutes of continuous electrofishing, a total of twenty-four hours, in the littoral zones of prominent habitat types represented in the reservoir. Results of the SSS monitoring were calculated using Shoreline Assessment Habitat Index (SAHI), Relative -Stock Density (RSD), PSD, and Wr.. S -Habitattype is evaluated using, the SAHI metric and is a critical component incorporated into the spring sport fish survey. The resultant habitat designations (good, fair and poor) are correlated to black bass abundance (numbers/hour). RSD is the number of fish greater than a minimum preferred length in a stock divided by the number of fish greater than or equal to a minimum stock size. PSD is the number of fish greater than or equal to a minimum quality length in a sample divided by the number of fish greater than or equal to a minimum stock length. Wr is an index that quantifies fish condition and the preferred range value is 90-105% for moderate density bass populations such as those found in the Tennessee Valley latitudes. Results and Discussion Fish Community In the autumn of 2004, both the SQN downstream and the upstream station scored "Good" (41 and 49), respectively using the RFAI analysis methodology (Tables I and 2). RFAI scores obtained from VS monitoring stations located upstream and downstream of the SQN discharge over the past several years have revealed consistently "Good" fish community results (Table 3 and Figure 2). Regardless of which downstream station was used, the upstream station rating remained in the "Good" range and ihe downstream continued in the "Good" range, on average . (Table 3 and Figure.2). As indicated in Table 3, between 1993 and 2004, the average RFAI 5

score for the upstream station was 45 (75 percent of the maximum score). The two downstream

• stations (i.e., SQN transition and forebay) both averaged 44 "Good" (73 percent of the maximum score). Electrofishing and gill netting catch rates for individual species from the downstream station are listed in Table 4 and 5. Based on the average upstream and downstream RFAI scores, 2004 macroinvertebrate community data, and the defining characteristics for a BIP, it can be concluded that SQN operation has had no impact on the Chickamauga Reservoir resident fish community, on average, for ten sampling seasons (Table 3).

Benthic Macroinvertebrate Community Table 6 provides ratings for each metric as well as the overall benthic index score for both monitoring sites. Table 7 sufrmarizes density by taxon at the upstream (TRM 490.5) and downstream (TRM 482) collection stations. The upstream and downstream comparisons produced benthic index scores of.29 (Good) and 35 (Excellent), respectively, indicative of a BIP (Table 8). Therefore, it appears that SQN has had no adverse effect on the benthic macroinvertebrate community immediately downstream from the plant. Table 8 provides benthic index scores from VS monitoring at the forebay (TRM 472.3) and transition zone stations from 1994 to 2004. The Chickamauga forebay zone sample station is of sufficient distance downstream (I1 miles) that results would not be expected to reflect plant effects. The similar scores from TRM 472.3 and TRM 482 also indicate that SQN has had no effect on the macroinvertebrate community immediately downstream from the plant (Table 8). Sport Fishing Index In the autumn of 2003, Chickamauga Reservoir's sport fish population received similar SFI

• scores compared to the seven year average. Black bass, largemouth bass, smallmouth bass,,

spotted bass, crappie and white bass received higher scores than their seven year averages (Table 9 and Figure 3). Both sauger and striped bass received lower scores in 2003 compared to scores in 2002. The score for sauger was the lowest it has been since 1997 when this analysis technique was implemented by TVA. Historical data indicate that SFI scores typically vary among years. However if future scores would continue to decline, further investigation would be warranted. Channel catfish, crappie and white bass received their highest SFI scores to date. Crappie and white bass scores increased from 38 to.42 and 30 to 40, respectively (Table 9 and Figure 3). Tables 10 and 11 illustrate SFI scoring criteria for population metrics and creel quantity and quality. Sauger, striped bass, and channel catfish are easily caught during their spring migration to preferred spawning habitats. Fishing creel surveys conducted in the spring would better describe and evaluate, these species compared to only using autumn fisheries creel surveys. Sprin2 Sport Fish Survey A total of 18 hours of electrofishing resulted in 736 black bass collected; of these, 60.2% were harvestable size (10" or greater). Of the total black bass collected, 579 were largemouth, 120 were spotted and 37 were smallmouth bass. Overall catch rate (.40.9 fish/hr.) was less than the 2003 survey (62.0/hour)(Table 12). The average weight of harvestable sized black bass was 1.3 pounds. The largest black bass collected was a 6.6 pound largemouth bass taken from Skull Island. Numbers of lunker bass were well represented with a total of 21 bass greater than three A pounds, 13 greater than four pounds and 6 over five pounds. In 2003, 23 bass over fourpounds 6

were collected and eight of them were five pounds plus. Length frequency histograms illustrated a bimodal distribution with the dominant size classes being the 10-1 1 inch and 13-14 inch groups (Figure 4). Good representation of the memorable category sized fish was also evident. Habitat type is a critical component that has been incorporated into the spring sportfish survey. This metric is derived from the SAL-TI developed by Resource Stewardship Group. The resultant habitat designations (good, fair and poor) are correlated to black bass abundance (numbers/hour). A positive correlation of habitat type-to-black bass abundance was evident on Chickamauga Reservoir during the 2004 survey. Among the three areas sampled, the correlationis at Skull Island were positive but Sale Creek and Harrison Bay showed some variability among habitat types, i.e., the catch rates (abundance) did not align with the habitat designation types (Tables 13). Overall catch rates for the reservoir were 49, 41 and 34 at the good, fair.and poor habitats, respectively (Table 14).. RSD is the number of fish greater than a minimum preferred length in a stock divided by the number of fish greater than or equal to a minimum stock size. The RSD value (15). fell within the desirable range (10-25) (Figure 5). The PSD is the number of fish greater than or equal to a minimum quality length in a sample divided by the number of fish greater than or equal to a minimum stock length. The PSD value (53) was also within the preferred range (40-70) (Figure 6). Wr is an index that quantifies fish condition and the preferred range value is 90-105% for moderate density bass populations such as those found in the Tennessee Valley latitudes. The

• values shown in Figure 7 are designated by inch groups which reflect the classical categories, i.e., 0-7 = substock, 8-11 = stock, 12-14 = quality, 15-19 = preferred, 20-24 = memorable and 25+ = trophy., All categories fell within the desired range, which reflects excellent condition of black bass in all size groups of the population. Field observations of large numbers of prey fish indicate an abundance of available forage for all size classes of black bass.

A total of 106 crappie (88 black and 18 white crappie) was also collected during the survey. The crappies were collected predominantly from tree tops, stumps and other physical structures in shallow water. 7

Literature Cited Dycus, D. L. and D. L. Meinert. 1993. Reservoir Monitoring, Monitoring and Evaluation of Aquatic Resource Health and Use Suitability in Tennessee Valley Authority Reservoirs. Tennessee Valley Authority, Water Resources, Chattanooga, Tennessee, TVA/WM-93/15. Hickman, G. D. 2000. Sport Fish Index (SFI), A Method to Quantify Sport Fishing Quality. Environmental Science & Policy 3 (2000)S 117-S125. Tennessee Department of Environment and Conservation. 2000. Draft NPDES Permit Number TN0026450. Tennessee Valley Authority. 1996. A Supplemental 316(a) Demonstration for Alternative Thermal Discharge Limits for Sequoyah Nuclear Plant, Chickamauga Reservoir, Tennessee. Tennessee Valley Authority, Engineering Laboratory, Norris, TN. WR96-1-45-145. 87 pp. 0 0 8

Table 1. Scoring Results for the Twelve Metrics and Overall Reservoir Fish Assemblage Index for Chickamauga Reservoir at the Sequoyah Downstream Sampling Station, 2004. Forebay Transiion TRM 472.3 ..........

           .Metric                                 Obs          Score A. Species richness and composition

1. Number of species 25 3

2. Number of centrachid 7 5 species

3. Number of benthic 3 I invertivores

4. Number of intolerant 5 5 species

5. Percent tolerant species electrofishing 37.2 1.5 gill netting 30.6 0.5

6. Percent dominance by electrofishing 33.8 1.5 one species gill netting 27.8 1.5

7. Number non-native electrofishing 0.4 2.5 species gill netting 0 2.5

8. Number of top 8 5 carnivore species B. Trophic composition

9. Percent top carnivores electrofishing 10.9 2.5 gill netting 48.9 1.5

10. Percent omnivores electrofishing 9.5 2.5 gill netting 42.8 0.5 C. Fish abundance and health

11. Average number per electrofishing 51.3 0.5 run gill netting 18.0 1.5

12. Percent anomalies electrofishing 1.0 2.5 gill -netting 0 2.5 RFAI 43 Good 9

Table 2. Scoring Results for the Twelve Metrics and Overall Reservoir Fish Assemblage Index for Chickamauga Reservoir at the Upstream Sampling Station, 2004. Trii~io~i i2Inflow TRM 495TRiV 529.0 Metric Obs Score A. Species richness and composition I. Number of species 29 5

2. Number of centrachid 7 5 species

3. Number of benthic 4 3 invertivores

4. Number of intolerant 4 3 species

5. Percent tolerant species electrofishing 64.8 1.0 gill netting 0 0

6. Percent dominance by electrofishing 50.0 1 one species gill netting 0.0 0

7. Number non-native electrofishing 0.5 5 species gill netting 0 0

8. Number of top 10 5 carnivore species B. Trophic composition 9, Percent top carnivores electrofishing 16.9 3 gill netting 0 0

10. Percent omnivores electrofishing 51.2 3 gill netting 0 0 C. Fish abundance and health

11. Average number per electrofishing 99.9 3 run gill netting 0 0

12. Percent anomalies electrofishing 1.3 5 gill netting 0 0

 . RFAI                                                                                       42 m

Good 10

Table 3. Recent (1993-2004) RFAI Scores Collected as Part of the Vital Signs Monitoring Program Upstream and Downstream of Sequoyah Nuclear Plant. Station Reservoir Location 1993 1994 1995 1997 1999 2000* 2001 2002* 2003 2004 Upstream Chickamauga TRM 49 40 46 39 45 46 45 51 42 49 490.5 Sequoyah Chickamauga TRM 41. 48 46 43 45 41 Transition 482.0 Forebay Chickamauga TRM 44 44 47 39 45 45 48 46 43 43 472.3

*The 2000, and 2002, sample years were not part of the VS monitoring program, however the same methodology was applied.

11

Table 4. Species Listing and Catch Per Unit Effort for the Embayment and Sequoyah Transects During the Fall Electrofishing and Gill Netting on Chickamauga Reservoir, 2004 (Electrofishing Effort = 300 Meters of Shoreline and Gill Netting Effort = 10 Net-Nights). Forebay TRM 472.3 Transition TRM 482.0 Electrofishing Electrofishing Gill Netting Electrofishing Electrofishing Gill Netting Catch Rate Catch Rate Catch Rate Catch Rate Catch Rate Per Catch Rate Common Name Per Per Per Per Hour Per Run Hour Net Night Run Net Night Spotted gar - - - I Skipjack herring 3.30 1.50. Gizzard shad 3.13 16.73 5.00 9.80 49.16 4.70 Threadfin shad 3.40 18.15 1.07 5.35 Common carp 0.20 1.07 0.53 2.68 Golden shiner 0.80 4.27 0.10 0.20 1.00 1.50 Emerald shiner 17.33 92.53 12.20 61.20 Spotfin shiner 0.20 1.07 0.07 0.33 Bluntnose minnow 0.20 1.00 Smallmouth buffalo 0.07 0.33 Spotted sucker 0.40 2.14 0.20 0.40 2.01 0.10 Blue catfish 1.40 0.80 Channel catfish 0.73 3.91 1.20 1.00 5.02 0.70 A~athead catfish 0.40 2.14 0.50 0.20 White bass 0.07 0.36 0.10 Yellow bass 2.80 1.70 Striped bass 0.10 Warmouth 0.33 1.78 Redbreast sunfish 4.53 24.20 3.73 18.73 Green sunfish 0.33 1.78 Bluegill 7.47 39.86 0.2.0 18.47 92.64 0.50 Longear sunfish 0.27 1.42 0.47 2.34 Redear sunfish 2.13 11.39 0.40 5.07 25.42 0.80 Smallmouth bass 0.33 1.78 0.33 1.67 Spotted bass 2.07 11.03 0.50 1.93 9.70 1.80 Largemouth bass 2.40 12.81 0.20 2.73 13.71 0.40 White crappie 0.20 Black crappie 0.33 1.78 1.40 0.33 1.67 0.40 Logperch 0.40 2.14 0.07 0,33 Freshwater drum 1.27 6.76 0.70 0.87 4.35 0.50 Brook silverside 2.73 14.59 0.67 3.34 Chestnut lamprey - - - I . 'J.UI u.jj Total 51.25 273.69 18.00 60.81 304.99 15.9 Number Samples 15 10 15 10 Number Collected 769 180 912 159 Species Collected 26 15 23 16 12

Table 5. Species Listing and Catch Per Unit Effort for the Transition and Inflow Transects During the Fall Electrofishing and Gill Netting on Chickamauga Reservoir, 2004 (Electrofishing Effort = 300 Meters of Shoreline and Gill Netting Effort = 10 Net-Nights). Transition TRM 490.5 Inflow TRM 529.0 Electrofishing Electrofishing Gill Netting Electrofishing Electrofishing Catch Rate Catch Rate Catch Rate Catch Rate Catch Rate Common Name Per Per Per Per Per Run- Hour Net Night Run Hour Longnose gar - - 0.10 1.20 6.21 Spotted gar 0.53 2.73 - 0.07 0.34 Skipjack herring - - 2.80 - Gizzard shad 5.73 29.35 3.90 50.00 258.62 Threadfin shad 0.33 1.71 - 13.07 67.59 Largescale - - 0.07 0.34 Common carp 0.27 1.37 - 0.40 2.07 Golden shiner 0.40 2.05 0.10 0.07 0.34 Emerald shiner 4.13 21.16 - 0.60 3.10 Spotfin shiner 0.13 0.68 - 0.73 3.79 Bluntnose minnow 0.33 1.71 - 0.07 0.34

• Smallmouth buffalo - - 0.07 0.34 Spotted sucker 0.20 1.02 0.20 0.27 1.38 Golden redhorse 0.07 0.34 0.10 0.13 0.69 Blue catfish -- 1.50 -

Channel catfish 0.67 3.41 0.70 0.60 3.10 Flathead catfish 0.40 '2.05 0.40 0.60 3.10 White bass - - - 2.13 11.03 Yellow bass 0.07 0.34 3.10 1.73 8.97 Warmouth 0.53 2.73 0.20 - Striped bass - - 0.10 - Redbreast sunfish 2.87 14.68 - 1.27 6.55 Green sunfish 0.07 0.34 - 0.33 1.72 Bluegill 14.60 74.74 0.20 5.93 30.69 Longear sunfish 0.87 4.44 - 2.13 11.03 Redear sunfish 5.07 25.94 1.90 4.27 22.07 Hybrid sunfish - - - 0.07 0.34 Smallmouth bass 1.20 6.14 - 1.67 8.62 Spotted bass 3.27 16.72 1.80 3.27 16.90 Largemouth bass 2.67 13.65 - 4.33 22.41 White crappie 0.13 0.68 0.40 2.07 0 13

Table 5. (continued) S Transition TRM 490.5 Inflow TRM 529.0 Electrofishing Electrofishing Gill Netting Electrofishing Electrofishing Catch Rate Catch Rate Catch Rate Catch Rate Catch Rate Common Name Per Per Per Per Per Run Hour Net Night Run Hour Black crappie 1.53 7.85 1.00 1.53 7.93 Yellow perch 0.13 0.68 - 0.07 0.34 Logperch 0.20 1.02 - 1.20 6.21 Sauger 0.20 - Freshwater drum 1.27 6.48 0.50 1.13 5.86 Brook silverside 0.87 4.44 - 0.53 2.76 Inland silverside 0.67 3.41 - - Chestnut lamprey 0.13 0.68 - - Total 49.34 252.54 18.80 99.94 516.85 Number Samples 15 10 15 Number Collected 740 188 1,499 Species Collected 30 18 32 0 14

Table 6. Individual Metric Ratings and the Overall Benthic Community Index Score for 0 Upstream and Downstream Stations near Sequoyah Nuclear Plant, Chickamauga Reservoir, November 2004. TRM 490.5 TRM 482 Upstream Downstream Metric Obs Rating Ohs Rating

1. Average number of taxa 7.4 5 7.2 5

2. Proportion of samples with long-lived organisms 90% 3 90% 5

3. Average number of EPT taxa 1.3 3 1.4 5

4. Average proportion of oligochaete individuals 7% 5 13.7% 5

5. Average proportion of total abundance comprised by the 70.9% 5 64.9% 5 two most abundant taxa

6. Average density excluding chironomids and 480 3 505 5 oligochaetes Zero-samples - proportion of samples containing no 0 5 0 5 organisms Benthic Index Score 29 35-Good Excellent

 *Scored with transition criteria.

Benthic Index Scores: Very Poor 7-12, Poor 13-18, Fair 19-23, Good 24-29, Excellent 30-35 15

Table 7. Average Mean Density Per Square Meter of Benthic Taxa Collected at Upstream and Downstream Stations near Sequoyah Nuclear Plant, Chickamauga Reservoir, November 2004. TRM Chickamauga Reservoir 490.5 Upstream Mean Occurrence Species Density per site Annelida Oligocheata Tubificidae 45 6 Branchiurasowerbyi 13 1 Limnodrilus hoffmeisteri 17 5 Hirudinea Rhynchobdellida Glossiphoniidae Helobdella stagnalis 22 6 Insecta Ephemeroptera Ephemeridae Hexagenia limbata 10rmm 45 5 Hexagenia limbata >10mm 23 5 Trichoptera Polycentropodidae Cyrnellusfraternus 2 1 Cernotinasp. 3 1 Leptoceridae Oecetis sp. 2 1 Diptera Chironomidae' Ablabesmyia annulata 7 4 Chironomus sp. 38 5 Coelotanypus sp. . 305 10 Mollusca. Gastropoda Lymnophila Planorbidae Gyralus parvus 2 1 Mesogastropoda Pleuroceridae Pleuroceracanaliculata 2 1 Viviparidae Campeloma decisum 2 1 Viviparus Georgianus 75 9 16

Table 7. (Continued) TRM Chickamauga Reservoir 490.5 Upstream Mean Occurrence Species Density per site Bivalvia Veneroida Corbiculidae Corbiculafluminea<10rmr 20 3 Corbiculafluminea>10mm 103 9 Dreissenidae Dreissenapolymorpha 7 1 Sphaeriidae Musculium transversum 172 10 Number of samples 10 Sum 903 Number of taxa 17 Number of EPT taxa 4 Sum of area sampled 0.60 TRM Chickamauga Reservoir 482 Downstream Mean Occurrence Species Density per site Annelida Oligocheata Naididae 2 1 Tubificidae 110 5 Branchiurasowerbyi 8 4 Limnodrilus hofjineisteri 23 2 Hirudinea 7 3 Rhynchobdellida Glossiphoniidae Helobdella stagnalis 7 3 Pharyngobdellida Erpobdellidae 3 2 Crustacea Amphipoda-Gammaridae Gammarus sp. 5 3 17

Table 7. (Continued) w TRM Chickamauga Reservoir 482. Downstream Mean Occurrence Species Density per site Insecta Ephemeroptera Ephemeridae Hexagenialimbata<10mm 25 4 Hexagenia limbata >10mm 37 4 Trichoptera Polycentropodidae 2 1 Cyrnellusfraternus 13 5 Diptera Chironomidae Ablabesmyia annulata 12 3 Axarus sp. 2 1 Coelotanypus sp. 87 8 Mollusca Gastropoda Mesogastropoda Viviparidae Viviparus georgianus 13 2 Viviparus sp. 92 6 Bivalvia Veneroida Corbiculidae Corbiculafluminea.<10mm 77 4 Corbiculafluminea>10mm 100 9 Sphaeriidae 13 1 Musculium transversum 105 9 Number of samples 10 Sum 742 Number of taxa 14 Number of EPT taxa 2 Sum of area sampled 0.60 0 18

Table 8. Recent (1994-2004) Benthic Index Scores Collected as Part of the Vital Signs Monitoring Program at Chickamauga Reservoir Transition (TRM 490.5 and TRM 482) and Forebay Zone (TRM 472.3) Stations. Site Reservoir Location 1994 1995 1997 1999 2000 2001 2002 2003 2004 Average Upstream Chickamauga TRM 33 29 31 31 23 25 23 31 29 28 490.5 Downstream Chickamauga TRM 482 23 3f 27 29 35 29 Downstream Chickamauga TRM 31 27 29 25 27 27 23 27 27 27 472.3 Note: No data were collected for 1996 and 1998. Scores that are considered very poor range from 7-12, poor range from 13-18, fair range from 19-23, good range from 23-29 and excellent range from 30-35. Table 9. Sport Fishing Index Results for Chickamauga Reservoir, 2003. Year Species 1997 1998 1999 2000 2001 2002 2003 1997-2003 Average SF1 Score Black bass 3.5 41 .25 35 31 34 34 34 Smallmouth bass 20 20 24 22 40 32 32 27 Spotted bass 20 37 24 40 26 32 32 30 Largemouth bass .34 37 34 32 28 36 36 34 Bluegill 30 32 33 32 32 31 32 Channel catfish 32 29 30 25 33 35 Crappie 32 31 31 32 38 42 35 Sauger 27 36 32 39 30 31 27 32 Striped bass 35 30 30 40 34 . 31 33 White bass 31 30 30 30 40 32 19

Table 10. Sport Fishing Index Populatiori Quantity and Creel Quantity and Quality Metrics and Scoring Criteria. Metrics Scores 5 10 15 Black bass Population (quantity) TVA electrofishing catch/hour < 15 15-31 > 31 State electrofishing (catch/hour) < 62 62-124 > 124 Creel (quantity)' Anglers (catch/hour) < 0.3 0.3-0.6 > 0.6 BAIT and BITE data < 1.1 1.1-2.3 > 2.3 Creel (quality) Pressure (hours/acre) <8 8-16 > 16 Largemouth bass Population (quantity)b TVA electrofishing catch/hour < 13 13-25 > 25 State electrofishing (catch/hour) < 53 53-106 > 106 Creel (quantity) Anglers (catch/hour) < 0.29 0.29-0.58 > 0.58 Creel (quality)

• Pressure (hours/acre) <8 8-16 > 16 Smallmouth bass Population (quantity)

TVA electrofishing catch/hour <4 4-8 >8 State electrofishing (catch/hour) <8 8-15 > 15 Creel (quantity) Anglers (catch/hour) < 0.-1 0.1-0.3 > 0.3 Creel (quality) Pressure (hours/acre) <8 8-16 > 16 Spotted bass Population (quantity) TVA electrofishing catch/hour <5 5-11 > 11 State electrofishing (catch/hour) < 14 14-27 > 27 Creel (quantity) Anglers (catch/hour) < 0.07 0:07-0.13 > 0.13 Creel (quality) Pressure (hours/acre) <8 8-16 > 16. 0 20

Table 10. (continued) W Metrics Scores 5 10 15 Sauger Population (quantity) Experimental gill net (catch/net night) <9 9-17 > 17 Creel (quantity) Anglers (catch/hour) < 0.5 0.5-1 > 1 Creel (quality) Pressure (hours/acre) <5 5-10 > 10 Channel catfish Population (quantity) Experimental gill net.(catch/net night) < 2 2-4 >4 Creel (quantity) Anglers (catch/hour) < 0.3 0.3-0.7 > 0.7 Creel (quality)

  ;Pressure (hours/acre)                      <9                    9-19                 > 19 aEach worth 2.5, 5.0, and7.5 points if both data sets are available.

bTVA electrofishing only used when state agency electrofishing data is unavailable. 0 21

Table 11. Sport Fishing Index Population Quality Metrics and Scoring Criteria. Scores 5 10 15 Metrics Population (quality) 1 2 3 PSD < 20 or> 80 20-39 or 61-80 40-60 RSDP (preferred) 0 or > 60 1-9 or 41-60 10-40 RSDM (memorable) 0 or> 25 1-4 or 11-25 5-10 RSDT (trophy) 0 <1 1 Wr (Stock-preferred-size fish) < 90 > 110 90-110 Table 12. Electrofishing Catch Rate, Mean Weight, Percent Harvestable, Numbers of Black Bass Greater than Five Pounds, Numbers of Black Bass Greater than Four Pounds and Largest Black Bass Collected, Chickamauga Reservoir Black Bass Surveys, 1995-2004. EF Catch Mean Largest Yea Rate Weipht  % Bass >4 Bass >5 bass _r (no./hr.) (lbs.) Harvestable lbs. lbs. (lbs.) 2004 40.9 1.3 60.2 13 6 6.6 2003 62.0 1.3 65.8 23 8 6.4 2002 57.4 1.1 59.4 9 4 6.6 2001 34.5 0.8 45.2 0 0 2.8 2000 34.4 1 51.2 3 0 4.8 1999 10.6 1.3 60.7 3 1 6.1 1998 37.2 1.1 44.5 9 2 6.6 1997 40.2 1 70.1 8 4 8.7 1996 51 1.2 42.6 13 9 7.9 1995 62 1.2 61.8 .28 12 8.3 22

Table 13. Black Bass Catch Per Hour Compared to Habitat Types by Location. Habitat Designation Reservoir and Site Good Fair Poor _Chickamauga Harrison Bay 62(4) 30(4) 47(4) Sale Creek 35(4) 58(4) 30(4) Skull Island 50(2) 37(8) 17(2) Watts Bar Blue Springs 57(3) 42(4) 42(5) Caney Creek 61 (4) 56(4) 59(4) Kingston 70(4) 31(3) 28(5) Watts Bar Dam 87(3) 51(6) 54(3) Catch per hour = number of fish collected per hour (= number of transects sampled at each location Table 14. Black Bass Catch Per Hour Compared to Habitat Types by Reservoir. HABITAT DESIGNATION Reservoir Good Fair Poor Chickamauga 49 41 34 Watts Bar 68 47 44 Wheeler 99 75 43 Catch per hour number of fish collected per hour 0 23

Quantity Parameters Quality Parameters Akngle Success Sampling CPUE Ainging PressUre SPecies Populatio Figure 1. Parameters used to calculate the Sport Fishing Index (SFI). 0/ 0 24

S o Annual RFAI Scores for Chickamauga 60 50 40 0 30 L.L 20 10

                  .0 1993    1994    1995    1996    1997    1998      1999 2000 2001 2002 2003 2004 Year Figure 2. RFAI scores from sample years between 1993 and 2004.

25

Chickamauga SFI Scores 1997-2003 60 50 E Black bass 40 A Largemouth bass O Smalimouth bass 0 Spotted bass 0 U EMCrappie U) 30

                                                                                                ýM Sauger M,                                                                                             *MStriped bass 11Bluegill 20                                                                                         WChannel catfish U White bass 10 0

1997 1998 19,99 2000 2001 2002 2003 Year Figure 3. Sport Fishing Index results for Chickamauga Reservoir between 1997 and 2003. 26

LENGTH FREQUENCY ALL SITES CHICKAMAUGA 2004 120 100 80 60 977 40 20 0 3 5 7 9 11 13 15 17 19 21 23 25 INCH GROUP Figure 4. Chickamauga Reservoir length frequency histogram, (all sites) spring 2004. RSD VALUES (Quality) MAINSTEM RESERVOIRS S SPRING 2004 50 45 40.- ~'A.: i : l*40'*

                      .35-30 0) 25                 ----                                                           . . ----

20 15 93 Desirable RSD 15 Range 10 51 0-, . .. 0*.: Z: 0.f.: w

.,v. :0 -. ,.

                                                                                                       * *::./:::
                                                                                                            .S!i~ ~il::
                                                                                                            *L:S: ..
                                                                                                      -:3~~~~~~:=

0

                             'f:!i Reservoir Figure 5. Relative stock density values for Tennessee River Reservoirs.

0 27

S PSID VALUES MAINSTEM RESERVOIRS SPRING 2004 10o 90 80 7 ,

                 ------ ----                                     --------- ------------- --/ -------         -Ti --   ---------

I

          ..70                                     -------------

60

          !"50 D--bý,      PSD Rý- _4                                  48 40         ----------------------------------- -----------------------------------------------------------------

30

            .20
           .10
             *0.

I *I: I .1 I I Reservoir Figure 6. Proportional stock density values for Tennessee River Reservoirs. CHICKAMAUGA Wr ALL SITES 2004 I=Pe rcent #of Fish

                       .100                                                                               250 80                                                                             .200 Lr -

60 150' 40 100, 20 50 0 Il 1 0. 0-7 8-11 12-14 15-19 20-24 25 + Relative Stock Size by Inch 'Group Figure 7. Chickamauga Reservoir mean relative weights (Wr) for largemouth bass broken out by RSD category and fish numbers. 0 28

Biological Monitoring of the Tennessee River Near Sequoyah Nuclear Plant Discharge 2005 . by Dennis S. Baxter Donny R. Lowery Greg P. Shaffer May 2006 Final Aquatic Monitoring and Management Knoxville, Tennessee

Table of Contents Page Introduction 1 Methods 2 Fish Community 2 Benthic Macroinvertebrate Community 4 Sport Fishing Index 4 Spring Sport Fish Survey 5 Results and Discussion 5 Fish Community. 5 Benthic Macroinvertebrate Community 6 Sport Fishing Index 6 Spring Sport Fish Survey 7 Literature Cited 81 List of Tables Table 1. Scoring Results for the Twelve Metrics and Overall Reservoir Fish Assemblage Index for Chickamauga Reservoir at the Sequoyah Downstream Sampling Station, 2004. 9 Table 2. Scoring Results for the Twelve Metrics and. Overall Reservoir Fish Assemblage Index for Chickamauga Reservoir at the Upstream Sampling Station, 2004. 10 Table 3. Recent (1993-2004) RFAI Scores Collected as Part of the Vital Signs Monitoring Program Upstream and Downstream of Sequoyah Nuclear Plant. 11 Table 4. Species Listing and Catch Per Unit Effort for the Embayment and Sequoyah Transects During the Fall Electrofishing and.Gill Netting on Chickamauga Reservoir, 2004 (Electrofishing Effort = 300 Meters of Shoreline and Gill Netting Effort = 10 Net-Nights). 12 Table 5. Species Listing and Catch Per Unit Effort for the Transition and Inflow Transects During the Fall Electrofishing and Gill Netting on Chickamauga Reservoir, 2004 (Electrofishing Effort = 300 Meters of Shoreline and Gill Netting Effort = 10 Net-Nights). 13 i

List of Tables

• (continued)

Page Table 6. Individual Metric Ratings and the Overall Benthic Community Index Score for Upstream and Downstream Stations near Sequoyah Nuclear Plant, Chickamauga Reservoir, November 2005. 15 Table 7. Average Mean

                          /1    Density Per Square Meter of Benthic Taxa Collected at Upstream and Downstream Stations near Sequoyah Nuclear Plant, Chickamauga Reservoir, November 2005.                                   16 Table 8. Recent (1994-2005) Benthic Index Scores Collected as Part of the Vital Signs Monitoring Program at Chickamauga Reservoir Transition (TRM 490.5 and TRM 482) and Forebay Zone (TRM 472.3) Stations.          18 Table 9. Sport Fishing Index Results for Chickamauga Reservoir, 2004.                18 Table 10. Sport Fishing Index Population Quantity and Creel Quantity and Quality Metrics and Scoring Criteria.                                           19 Table 11. Sport Fishing Index Population Quality Metrics and Scoring Criteria. 21

• Table 12. Electrofishing Catch Rate, Mean Weight, Percent Harvestable, Numbers of Black Bass Greater than Five Pounds, Numbers of Black Bass Greater than Four Pounds and Largest Black Bass Collected, Chickamauga Reservoir Black Bass Surveys, 1995-2005. 21 Table 13. Black Bass Catch Per Hour Compared to Habitat Types by Location. 22 Table 14. Black Bass Catch Per Hour Compared to Habitat Types by Reservoir. 22 List of Figures Figure 1. Parameters used to calculate the Sport Fishing index (SFI). 23 Figure 2. RFAI scores from sample years between 1993 and 2005. 24 Figure 3. Sport Fishing Index results for Chickamauga Reservoir between 1997 and 2004. 25 Figure 4. Chickamauga Reservoir length frequency histogram, (all sites) spring 2005. 26 0 Figure 5. Relative stock density values for Tennessee River Reservoirs. 26 ii

List of Figures (continued) Figure 6. Proportional stock density values for Tennessee River Reservoirs. 27 Figure 7. Chickamauga Reservoir mean relative weights (Wr) for largemouth I bass broken out by RSD.category and fish numbers. .27 Acronyms BI Benthic Macroinvertebrate Index BIP Balanced Indigenous Population NPDES National Pollutant Discharge Elimination System PSD Proportional Stock Density QA Quality Assurance RFAI Reservoir Fish Assemblage Index RSD Relative Stock Density RSDM Relative Stock Density of Memorable-sized RSDP Relative Stock Density of Preferred-sized . RSDT Relative Stock Density bf Trophy-sized SAHI Shoreline Assessment Habitat Index SFI Sport Fishing Index SQN Sequoyah Nuclear Plant SSs Spring Sport Fish Survey TRM Tennessee River Mile TVA Tennessee Valley Authority VS Vital Signs Wr Relative Weight 0, ill

Introduction Section 316(a) of the Clean Water Act specifies that industrial, municipal, .and other facilities must obtain permits if their discharges go directly to surface waters. Industries responsible for point-source dischargers of heated water can obtain a variance from state water quality standards if the industry can demonstrate compliance with thenmal criteria by documenting the maintenance of Balanced Indigenous Populations (BIP) of aquatic life in the vicinity of its discharge. Sequoyah Nuclear Plant's (SQN) current National Pollutant Discharge Elimination System (NPDES) permit number TN0026450 states, "For Section 316(a), the permittee shall summarize previous data and indicate whether significant changes have occurred in plant operation, reservoir operations or in stream biology that would necessitate that significant changes to the permitted variance." The permittee shall use the Reservoir Fish Assemblage Index (RFAI) to assess Chickamauga Reservoir fish community health. Any apparent declines in the fish community health will be further investigated to discover whether the decline is a valid conclusion and if the decline is real to identify possible sources for the fish community decline. As part of the identification of potential sources for the decline, the instream effects of the discharges made under this permit will be investigated (TDEC 2000). In response to this requirement, Tennessee Valley Authority's (TVA's) Vital Signs (VS) monitoring program (Dycus and Meinert 1993) will be used to evaluate areas of Chickamauga Reservoir upstream and downstream of SQN discharge. The purpose of this document is to briefly summarize and provide the Tennessee Department of Environment and Conservation results of comparisons between current and historical monitoring data. Prior to 1990, TVA focused on reservoir ecological assessments to meet specific needs .as they arose. In 1990, TVA instituted a Valley-wide VS monitoring program which is a broad-based evaluation of the overall ecological conditions in major reservoirs. Data are evaluated with a multi-metric monitoring approach utilizing five environmental indicators: dissolved oxygen, chlorophyll, sediment quality, benthic macroinvertebrate community, and the fish community.. When this program was initiated, specific evaluation techniques were developed for each indicator, and these techniques were fine-tuned to better represent ecological conditions. The outcome of this effort was development of multi-metric evaluation techniques for the fish assemblage (i.e., RFAI) and the benthic community, as described below. These multi-metric evaluation techniques have proven successful in TVA's monitoring efforts as well as other. federal and state monitoring programs. Therefore, they will form the basis of evaluating these monitoring results. For consistency, only RFAI analyses between 1993 and 2005 will be

 .utilized. The Benthic Macroinvertebrate Index (BI) is used primarily to support the RFAI analysis.

In the past, the Sport Fishing Index (SFI) was used in support of a thermal variance request at SQN (TVA 1996). The SFI was developed to quantify sport'fishing quality for individual sport fish species. The SFI provides biologists with a reference point to measure the quality of a sport fishery. Comparison of the population sampling parameters and creel results for a particular sport fish species with expectations of these parameters from a high quality fishery (reference conditions) allows for the determination of fishing quality. Indices have been developed for 0 I

black bass (largemouth, smallmouth and spotted bass), sauger, striped bass, bluegill, and channel

• catfish. Each SF1 relies on measurements of quantity and quality aspects of angler success and fish population characteristics.

In recent years, SIl information has been used to describe the quality of the resident fishery in conjunction with compliance monitoring, thermal variance requests, and other regulatory issues at TVA nuclear plants in Tennessee. Similar NPDES compliance monitoring programs using the methodologies described above are also being performed at Browns Ferry Nuclear, Colbert and Widows Creek Fossil Plants in Alabama. The TVA Spring Sport Fish Survey (SSS) is conducted to evaluate the sport fish population of TVA Reservoirs. The results of the survey are used by state agencies to protect, improve and assess the quality of sport fisheries. Predominant habitat types in the reservoir are surveyed to determine sport fish abundance. In addition to accommodating TVA and state databases, this surveying method aligns with TVA Watershed Team and TVA's Reservoir Operations Study objectives. Sample sites are selected using the shoreline habitat characteristics employed by the Watershed Teams. The survey predominantly targets three species of black bass (largemouth, smallmouth, and spotted bass) and black and white crappie. These species are the predominant sport fish sought after by fisherman. Methods Fish Community Reservoirs are typically divided into three zones for VS Monitoring - inflow, transition and U forebay. The inflow zone is generally in the upper reaches of the reservoir and is riverine in nature; the transition zone or mid-reservoir is the area where water velocity decreases due to increased cross-sectional area, and the forebay is the lacustrine area near the dam. The Chickamauga Reservoir inflow zone sample site is located at Tennessee River Mile (TRM) 529.0; the transition zone sampling site is located at TRM 490.5 and the forebay zone sampling site is located at TRM 472.3. The VS transition zone, which is located approximately 7.2 river miles upstream of the SQN discharge (TRM 483.3), will be used to provide upstream data for the 316(a) thermal variance studies performed in sample years between 1993 and 2005. An additional transition station was later added downstream of the SQN discharge to more closely monitor Chickamauga Reservoir aquatic communities in close proximity to the SQN thermal effluent. This station is located at TRM 482.0 and will be used for downstream comparisonis of aquatic communities for the 1999 through 2005 sample seasons. The forebay zone, will serve as the downstream station for 1993 through 1995 and 1997 sample seasons. Fish samples consisted of fifteen 300-meter electrofishing runs (approximately 10 minutes duration) and ten experimental gill net sets (five 6.1 meter panels with mesh sizes of 2.5, 5.1, 7.6, 10.2, and 12.7. cm) per station. Attained values for each of the 12 metrics were compared to reference conditions for transition zones of mainstream Tennessee River reservoirs and assigned scores based upon three categories hypothesized to represent relative degrees of degradation: 2,

least degraded -5; intermediate -3; and most degraded -1. These categories are based on

• expected" fish community characteristics in the absence of human-induced impacts other than impoundment. Individual metric scores for a station are summed to obtain the RFAI score.

Comparison of the attained RFAI score from the potential impact zone to a predetermined criterion has been suggested as a method useful in identifying presence of normal community structure and function and hence existence of a BIP. For multi-metric indices, two criteria have been suggested to ensure a conservative screening for a BIP. First, if an RFAI score reaches 70 percent of the highest attainable score (adjusted upward to include sample variability), and second, if fewer than half of RFAI metrics potentially influenced by thermal discharge receive-a low (1) or moderate (3) score, then normal community structure and function would be present indicating that a BIP existed. Under these conditions, the heated discharge would meet screening criteria and no further evaluation would be needed. The range of RFAI scores possible is from 12 to 60. As discussed in detail below, the average variance for RFAI scores in TVA reservoirs is 6 (+ 3). Therefore, any location that attains an RFAI score of 45 (42 + our sample variance of 3) or higher would be considered to demonstrate a BIP. It must be stressed that scores below this endpoint do not necessarily reflect an adversely impacted fish community. The endpoint is used to serve as a conservative screening level; for example, any fish community that meets these criteria is-obviously not adversely impacted. RFAI' scores below this level would require a more in-depth look to determine if a BIP exists. If a score below this criterion is obtained, an inspection of individual RFAI metric results would be an initial step to help identify if SQN operation is a contributing factor. This approach is a ppropriate if a validated multi-metric index is being used and scoring criteria applicable to the zone of study are available. Upstream/downstream stations comparisons can be used to identify if SQN operation is adversely affecting the downstream fish community as well. A similar or higher RFAI score at the downstream station compared to the upstream (control) station is used as one basis for determining presence/absence of SQN operational impacts on the resident fish community. Definition of "similar" is 'integral to accepting the validity of these interpretations. The Quality Assurance (QA) component of VS monitoring deals with how well the RFAI scores can be repeated and is accomplished by collecting a second set of samples at 15-20 percent of the stations each year. Experience to date with the QA component of VS shows that the comparison of RFAI index scores from 54 paired sample sets collected over a seven year period ranged from 0 to 18 points, the 7 5 th percentile was 6, the 90th percentile was 12. The mean difference between these 54 paired scores is 4.6 points with 95 percent confidence limits of 3.4 and 5.8. Based on these results, a difference of 6 points or less is the value selected for defining "similar" scores between upstream and downstream fish communities. That is, if the downstream RFAI score is within 6 points of the upstream score, the communities will be considered similar. It is important to bear in mind that differences greater than 6 points can be expected simply due to method variation (25 percent of the QA paired sample sets exceeded that value). When this occurs, a metric-by-metric examination will be conducted to determine what caused the difference in scores and the potential for the difference to be thermally related. /* Benthic Macroinvertebrate Community 3

Ten benthic grab samples were collected at equally spaced poinits along the upstream and downstream transects. A Ponar sampler was used for most samples but a Peterson sampler was used when heavier substrate was encountered. Collection and processing techniques followed standard VS procedures. Bottom sediments were washed on a 533 t screen and organisms were then picked from, the screen and remaining substrate and identified to Order or Family level in the field using no magnification. Befithic community results.were evaluated using seven community characteristics or metrics. Results for each metric were assigned a rating of 1, 3, or 5 depending upon how they compared to reference conditions developed for VS sample sites. The ratings for the seven metnics were.summed to produce a total benthic score for each sample site. Each reservoir section (inflow, transition, or forebay) differs in their maximum potential for benthic diversity; thus,the criteria for assigning metric ratings were adjusted accordingly such that the total benthic scores from sites on different reservoir sections are comparable. Potential scores ranged from 7 to 35. Ecological health ratings ("Poor," "Fair," or "Good") are then applied to scores. A similar or higher benthic index score at the downstream site compared to the upstream site is used as basis for determining if SQN's thermal discharge is having no effect on the Chickamauga Reservoir benthic community. The QA component of VS monitoring shows that the comparison of benthic index scores from 49 paired sample sets collected over a seven year period ranged from 0 to 14 points, the 75th percentile was 4, the 90th percentile was 6. The mean difference between these 49 paired scores is 3.1 points with 95 percent confidence limits of 2.2 and 4.1. Based on these results, a difference of 4 points or less is the value selected for defining "similar" scores between upstream and downstream benthic communities. That is, if the downstream benthic score is within 4

• points of the upstream score, the communities will be considered similar and it will be concluded that SQN has had no effect. Once again, it is important to bear in mind that differences greater than 4 points can be expected simply due to method variation (25 percent of the QA paired sample sets exceeded that value). When this occurs, a metric-by-metric examination will be conducted to determine what caused the difference in scores and the potential for the difference to be thermally related.

Sport Fishin2 Index Calculations described by Hickman (2000) were used to compare SF1 values for selected

 -quantity and quality parameters from creel and population samples to expected Values that would occur in a good or high quality fishery. Quantity parameters include angler success and catch per unit effort from standard population samples (electrofishing, trap andexperimental gill netting). Population quality is based on measurement of five aspects of each resident sport fish community. Four of these aspects address size structure (proportional number of fish'in each length group) of the community, Proportional Stock Density (PSD), Relative Stock Density of Preferred-sized fish (RSDP), Relative Stock Density of Memorable-sized fish (RSDM), and Relative Stock Density of Trophy-sized fish (RSDT) (Figure 1). Relative weight (Wr), a measure of the average condition of individual fish makes up the fifth population quality aspect.

As described by Hickman (2000), observed values were compared to reference ranges and. assigned a corresponding numerical value. The SF1 value is calculated by adding the scores for quantity and quality from existing data and multiplying by two when only creel or population data are available. Species received a low score when insufficient numbers of individuals were A captured to reliably determine proportional densities or relative weights, for particular 4

parameters. SFI scores are typically compared to average>Tennessee Valley reservoir scores; however, Valley-wide scores are unavailable from natural resource agencies. Therefore, Chickamauga Reservoir fish species scores will be compared to previous years. The 2004 State Fisheries gill netting and creel data were not available for analysis before this report was submitted; therefore 2003 SFI data were used for analysis. Sprin2 Sport Fish Survey A spring sportfish survey was conducted on Chickamauga Reservoir March 2005. Twelve sites at three locations including Harrison Bay, Ware Branch and Sale Creek were sampled using boat-mounted electrofishers. Each run consisted of thirty minutes of continuous electrofishing in the littoral zones of prominent habitat types represented in the reservoir. Summer pool level for Chickamauga is 682.5 msl and sampling was conducted at 676.7 msl. TVA Fisheries Biologists use electrofishing equipment to sample fish at selected locations. In that process an electric current is used to temporarily stun the fish so they float to the surface of the water. The fish are collected with nets, counted, weighed, measured, and released unharmed. A total of twenty-four hours of electrofishing was conducted in the littoral zones of prominent habitat types represented in the reservoir. Results of the SSS monitoring were calculated using Shoreline Assessment Habitat Index (SALHI), Relative Stock Density (RSD), PSD, and Wr. Habitat type is evaluated using the SAHI metric and is a critical component incorporated into the spring sport fish survey. The resultant habitat designations ("Poor," "Fair," or "Good") are correlated to black bass abundance (numbers/hour). RSD is the number of fish greater than a minimum preferred length in a stock divided by the number of fish greater than or equal to a minimum stock size. PSD is the number of fish greater than or equal to a minimum-quality length in a sample divided by the number of fish greater than or equal to a minimum stock length. Wr is an index that quantifies fish condition and the preferred range value is 90-105% for moderate density bass populations such as those found in the Tennessee Valley latitudes. Results and Discussion Fish Community In the autumn of 2005, both the SQN downstream and the upstream station scored "Fair" and "Good" (39 and 48), respectively using the RFAI analysis methodology (Tables I and 2). RFAI scores obtained from VS monitoring stations located upstream and downstream of the SQN discharge over the past several years have revealed consistently "Good" fish community results (Table 3 and Figure 2). Regardless of which downstream station wasused, the upstream and downstream station rating remained in the "Good" range, on average (Table 3 and Figure 2). As indicated in Table 3, between 1993 and 2005, the average RFAI score for the upstream station was 47 (78 percent of the maximum score). The two downstream stations (i.e.; SQN transition 5

and forebay) both averag6d "Good" with scores of 43 and 45 (72 and 75 percent of the maximum

• score), respectively. Electrofishing and gill netting catch rates for individual species from the downstream station are listed in Table 4 and 5. Based on the average upstream and downstream RFAI scores, 2005 macroinvertebrate community data, and the defining characteristics for a BIP, it can be concluded that SQN operation has had no impact on the Chickamauga Reservoir resident fish community, on average, for eleven sampling seasons (Table 3).

Benthic Macroinvertebrate Community Table 6 provides ratings for each metric as well as the overall benthic index score for both monitoring sites. Table 7 summarizes density by taxon at the upstream (TRM 490.5) and downstream (TRM 482) collection stations. Both the upstream and downstream stations produced benthic index scores of 31 (Excellent), indicative of a BIP (Table 8). Therefore, it appears that SQN has had no adverse effect on the benthic macroinvertebrate community immediately downstream from the plant. Table 8 provides benthic index scores from VS monitoring at the forebay (TRM 472.3) and transition zone stations from 1994 to 2005. The Chickamauga forebay zone sample station is of sufficient distance downstream (11 miles) that results would not be expected to reflect plant effects. The similar scores from TRM 472.3 and TRM 482 also indicate that SQN has had no effect on the macroinvertebrate community immediately downstream from the plant (Table 8). Sport Fishin2 Index In the autumn of 2004, Chickamauga Reservoir's sport fish population received similar SFI scores compared to the eight year average. Largemouth bass, smallmouth bass, spotted bass,

• crappie, bluegill, and channel catfish received higher scores than their seven year averages (Table 9 and Figure 3). Sauger, crappie, and black bass received lower scores in 2004 compared to scores in 2003. The score f6r sauger was the lowest it has been since 1997 when this analysis technique was implemented by TVA. This quality assessment is not necessarily indicative of a trend. Historical data indicate that SFI scores typically vary among years. However if future scores would continue to decline, further investigation would be warranted. Channel catfish, largemouth bass, and bluegill received their highest SFI scores to date. Channel catfish scores increased from 33 to 38 (Table 9 and Figure 3). Tables 10 and 11 illustrate SFI scoring criteria for population metrics and creel quantity and quality.

Sauger, striped bass, and channel catfish are easily caught during their spring migration to preferred spawning habitats. Fishing creel surveys conducted in the spring would better describe and evaluate these species compared to only using autumn fisheries creel surveys. 0 6

Sprin2 Sport Fish Survey A total of 18 hours of electrofishing resulted in 1308 black bass collected; of these, 36.9% were harvestable size (10" or greater). This was a significant reduction in harvestable size bass compared to the 2004 survey results (60.2%). Of the total black bass collected, 1080 were largemouth, 178 were spotted and 50 were smallmouth bass. Overall catch rate (72.6 fish/hr.) was substantially greater than the 2004 survey (40.9/hour) (Table 12). The average weight of harvestable sized black bass was 1.3 pounds. The largest black bass collected was a 6.2 pound largemouth bass taken from Sale Creek. Numbers of lunker bass were well represented with a total of 19 bass greater than three pounds, 15 greater than four pounds and 9 over five pounds. In 2004, 13 bass over four pounds were collected and 6 of them were five pounds plus. Length frequency histograms illustrated a bimodal distribution with the dominant size classes being the 6-8 inch and 11-12 inch groups (Figure 4). Good representation of the memorable category sized fish was also evident. Habitat type is a critical component that has been incorporated into the spring sportfish survey. This metric is derived from the SAH-I- developed by Resource Stewardship Group. The resultant habitat designations ("Poor," "Fair," or "Good") are correlated to black bass abundance (numbers/hour). A positive correlation of habitat type-to-black bass abundance was evident on Chickamauga Reservoir during the 2004 survey. Among the three areas sampled, the correlations at Harrison Bay were positive but Sale Creek and Skull Island showed some variability among habitat types, i.e.,the catch rates (abundance) did not align with the habitat designation types (Tables, 13). Overall catch rates for the reservoir were 75, 84, and 52 at the "Good," "Fair," and "Poor" habitats, respectively (Table 14). RSD is the number of fish greater than a minimum preferred length in a stock divided by the number of fish greater than or equal to a minimum stock size. The RSD value (15) fell within the desirable range (10-25) (Figure 5). The PSD is the number of fish greater than or equal to a minimum quality length in a sample divided by the number of fish greater than or equal to a minimum stock length. The PSD value (48) was also within the preferred range (40-70) (Figure 6). Wr is an index that quantifies fish condition and the preferred range value is 90-105% for moderate density bass populations such as those found in the Tennessee Valley latitudes. The values shown in Figure 7 are designated by inch groups which reflect the classical categories, i.e., 0-7 = substock, 8-11 = stock, 12-14 = quality, 15-19 = preferred, 20-24 = memorable and 25+.= trophy. All categories fell within the desired range, which reflects excellent condition of black bass in all size groups of the population. Field observations of large numbers of prey fish indicate an abundance of available forage for all size classes of black bass. A total of 140 crappie (118 black and 22 white crappie) was also collected during the survey. The crappies were collected predominantly from tree tops, stumps and other physical structures in shallow water. 0 7

Literature Cited Dycus, D. L. and D..L. Meinert. 1993. Reservoir Monitoring, Monitoring and Evaluation of Aquatic Resource Health and Use Suitability in Tennessee Valley Authority Reservoirs. Tennessee Valley Authority, Water Resources, Chattanooga, Tennessee, TVA/WM-93/15. Hickman, G. D. 2000. Sport Fish Index (SFI), A Method to Quantify Sport Fishing Quality. Environmental Science & Policy 3 (2000) S1 17-S125. Tennessee Department of Environment and Conservation. 2000. Draft NPDES Permit Number TN0026450. Tennessee Valley Authority. 1996. A Supplemental 316(a) Demonstration for Alternative Thermal Discharge Limits for Sequoyah Nuclear Plant, Chickamauga Reservoir, Tennessee. Tennessee Valley Authority, Engineering Laboratory, Norris, TN. WR96-1-45-145. 87 pp. 8

Table 1. Scoring Results for the Twelve Metrics and Overall Reservoir Fish Assemblage Index for Chickamauga Reservoir at the Sequoyah Downstream Sampling Station, 2005. Forebay 7ransii J. TRIVI 472.3 ......... Metric Obs Score A. Species richness and composition

1. Number of species 30 5

2. Number of centrachid 7 5 species

3. Number of benthic 4 3 invertivores

4. Number of intolerant. 6 5 species

5. Percent tolerant species electrofishing 71 0.5 gill netting 32.2 0.5

6. Percent dominance by electrofishing 42.2 1.5 one species gill netting 30.5 0.5

7. Number non-native electrofishing 0 2.5 0 species gill netting 0.4 2.5

8. Number of top 12 5 carnivore species B. Trophic composition

9. Percent top carnivores electrofishing 6.4 1.5 gill netting 51.7 2.5

10. Percent omnivores electrofishing 11.3 2.5 gill netting 40.5 0.5 C. Fish abundance and health

11. Average number per electrofishing 37.3 0.5 run gill netting 26.9 2.5.

12. Percent anomalies electrofishing 0.5 2.5 gill netting 0 2.5 RFAI 46 Good 0

9

Table 2. Scoring Results for the Twelve Metrics and Overall Reservoir Fish Assemblage Index for Chickamauga Reservoir at the Upstream Sampling Station, 2005. aiY itiiWOM Inflow

                                                   .I.
                                                    ...... i::i~~ii~i::::::....
                                                   *ii!*i~i!*i~iiiiiiiiii~ii~iiii~iiiiiiiiiiii~iiiiiii~ii~~i TRM 529.0 Metric                                                                                                    Obs          Score A. Species richness and composition

1. Number of species 27 3

2. Number of centrachid 6 5 species

3. Number of benthic 6 3 invertivores

4. Number of intolerant 6 5 species

5. Percent tolerant species electrofishing 58.6 1.0 gill netting 0 0

6. Percent dominance by electrofishing 30.5 3 one species gill netting 0 0

• 7. Number non-native electrofishing 1 5 species gill netting 0 0

8. Number of top 7 5 carnivore species B. Trophic composition

9. Percent top carnivores electrofishing 16.7 3 gill netting 0 0

10. Percent omnivores electrofishing 33.3 3 gill netting 0 0 C. Fish abundance and health

11. Average number per electrofishing 67 3 run gill netting 0 0

12. Percent anomalies electrofishing 2.2 3 gill netting 0 0 RFAI " 42 Good 0

10

Table 3. Recent (1993-2005) RFAI Scores Collected as Paft of the Vital Signs Monitoring Program Upstream and Downstream of Sequoyah Nuclear Plant. Station Reservoir Location 1993 1994. 1995 1997 1999 1993- 2000* 2001 2002* 2003 2004 2005 1993-2005 1999- Average T_ _Average Upstream Chickamauga TRM 490.5 49 40 46 39 45 44 46 45 51 42 49 48 45 (Good) (Good) Sequoyah Chickamauga TRM 482.0 41 41 48 46 43 45 41 39 43 Transition  : (Good) (Good) Forebay Chickamauga TRM 472.3 44 44 47 39 45 44 45 48. 46 43 43 46 45 (Good) (Good)

        *The 2000, and 2002, sample years were not part of the VS monitoring program, however the same methodology .was applied.

11

Table 4. Species Listing and Catch Per Unit Effort for the Embayment and Sequoyah Transects During the Fall Electrofishing and Gill Netting on Chickamauga Reservoir, 2005 (Electrofishing Effort = 300 Meters of Shoreline and Gill Netting Effort = 10 Net-Nights). Forebay TRM 472.3 Transition TRM 482.0 Electrofishing Electrofishing Gill Netting Electrofishing Electrofishing Gill Netting Catch Rate Catch Rate Catch Rate Catch Rate Catch Rate Per Catch Rate Common Name Per Per Per Per Hour Per Run Hour Net Night Run Net Night

*r~~tt~A   oer                ( 14            fI              -....

Longnose gar 0.07 0.35 0.10 Skipjack herring 8.20 1.70 Gizzard shad 2.40 12.50 7.40 13.53 70.98 8.70 Threadfin shad 1.53 7.99 1.73 9.09 Common carp 0.10 0.13 0.70 Golden shiner 1.73 9.03 1.07 5.59 Emerald shiner 3.40 17.71 4.73 24.83 Bluntnose minnow 0.07 0.35 Northern hogsucker 0.13 0.69 Smallmouth buffalo 0.07 0.35 Spotted sucker 0.20 1204 0.10 0.20 1.05 0.10 Blue catfish 2.90 2.30 nanel 'catfish 0.50 0.40 2.10 1.30 head catfish 0.07 0.35 0.50 0.33 1.75 0.80 White bass 0.20 0.30 Yellow "bass 1.30 0.13 0.70 1.80 Warmouth 0.13 0.70 Redbreast sunfish 5.20 27.08 10.13 53.15 Green sunfish 0.67 3.47 0.13 0.70 Bluegill 15.73 81.94 0.60 14.67 76.92 0.20 Longear sunfish 0.53 2.78 0.80 4.20 Redear sunfish 1.87 9.72 0.50 5.40 28.32 0.90 Smallmouth bass 0.27 1.39 0.07 0.35 Spotted bass 1.07 5.56 2.50 2.0 10.49 2.10 Largemouth bass 0.67 3.47 0.20 1.33 6.99 0.20 White crappie 0.10 Black crappie 0.13 0.69 0.80 0.40 2.10 0.20 Logperch 0.33 .1.74 0.40 2.10 Sauger 0.10 Freshwater drum 0.33 1.74 0.90 0.20 1.05 0.50 Brook silverside 0.67 3.47 0.40 2.10 Inland silverside 0.07 0.35 0.13 0.70 Total 37.27 194.10 26.90 58.51 307.01 21.20 Number SamDles 15 10 15 10 Number Collected 559 269- 878 212 Snecies Collected 23 17 24 15 12

Table 5. Species Listing and Catch Per Unit Effort for the Transition and Inflow Transects During the Fall Electrofishing and Gill Netting on Chickamauga Reservoir, 2005 (Electrofishing Effort = 300 Meters of Shoreline and Gill Netting Effort = 10 Net-Nights). Transition TRM 490.5 Inflow TRM 529.0 Electrofishing Electrofishing Gill Netting Electrofishing Electrofishing Catch Rate Catch Rate Catch Rate Catch Rate Catch Rate Common Name Per Per Per Per Per Run Hour Net Night Run Hour Longnose gar _ WY7 1) q/ V..J* Spotted gar 0.13 0.70 Skipjack herring 0.70 Gizzard shad 8.07 42.61 2.40 20.47 105.86 Threadfin shad 0.47 2.46 3.73 19.31 Mooneye 0.10 Common carp 0.07 0.35 0.40 2.07 Golden shiner 0.07 0.35 0.20 1.03 Emerald shiner 1.40 7.39 2.93 15.17 Spotfin shiner 0.07 0.35 0.27 1.38 Striped shiner 0.13 0.69 -* Bluntnose minnow 0.13 0.70 G Northern hogsucker 0.07 0.34 Spotted sucker 0.33 1.76 0.20 0.53 2.76 Black redhorse 0.07 0.35 0.13 0.69 Golden redhorse 0.53 2.76 Blue catfish 1.70 0.13 0.69 Channel catfish 0.60* 1.00 5.17 Flathead catfish 0.20 1.06 0.20 1.13 5.86 Yellow bass 2.50 0.87 4.48 Warmouth 0.07 0.35 Redbreast sunfish 4.33 22.89 1.93 10.00 Green sunfish 0.33 1.76 2.00 10.34 Bluegill 16.47 86.97 0.50 11.80 61.03 Longear sunfish 0.80 4.23 3.07 15.86 Redear sunfish 2.13 11.27 0.80 5.67 29.31 Hybrid sunfish 0.13 0.70 Smallmouth bass 1.60 8.45 1.67 8.62 Spotted bass 1.47 7.75 1.80 3.73 19.31 Largemouth bass 2.33 12.32 2.00 10.34 0 13

Table 5. (continued) Transition TRM 490.5 Inflow TRM 529.0 Electrofishing Electrofishing Gill Netting Electrofishing Electrofishing Catch Rate Catch Rate Catch Rate Catch Rate Catch Rate Common Name Per Per Per Per Per Run Hour Net Night Run Hour Black crappie 0.20 1.06 0.40 1.73 8.97 Yellow perch - - - 0.27 1.38 Logperch 0.20 1.06 - 0.27 1.38 Sauger - - 0.10 - Freshwater drum 0.13 0.70 0.60 0.20 1.03 Brook silverside 0.33 1.76 - 0.07 0.34 Inland silverside 0.27 1.41 - - Total 41.80 220.76 12.60 67.00 346.51 Number Samples 15 10 15 Number Collected 627 126 1005 Species Collected 26 14 29 0 14

Table 6. Individual Metric Ratings and the Overall Benthic Community Index Score for Upstream and Downstream Stations near Sequoyah Nuclear Plant, Chickamauga Reservoir, November 2005. TRM 490.5 TRM 482 UPstream Downstream Metric Obs Rating Obs Rating

1. Average number of taxa 6.8 5 6.6 5

2. Proportion of samples with long-lived organisms 0.9 5 90% 5

3. Average number of EPT taxa 0.9 5 0.7 3

4. Average proportion of oligochaete individuals 4.4% 5 15% 3

5. Average proportion of total abundance comprised by the 79.79% 3 78.99% 5 two most abundant taxa

6. Average density excluding chironomids and 479.2 3 573.5 5 oligochaetes

• Zero-samples - proportion of samples containing no 0 5 0 5 organisms Benthic Index Score 31 31 Excellent Excellent
• Scored with transition criteria.

Benthic Index Scores: Very Poor 7-12, Poor 13-18, Fair 19-23, Good 24-29, Excellent 30-35 0 15

Table 7. Average Mean Density Per Square Meter of Benthic Taxa Collected at Upstream and

• Downstream Stations near Sequoyah Nuclear Plant, Chickamauga Reservoir, November 2005.

Chickamauga Reservoir TRM 490.5 TRM 482 Upstream Downstream Species Mean Density Mean Density Tubellaria Tricladida Planariidae 2 Oligocheata Oligochaetes 19 103 Hirudinea 9 78 Crustacea Amphipoda Isopoda Insecta Ephemeroptera May'flies Ephemeridae Hexagenia (<=10 mm) 23 8 Hexagenia (>I 0 mm), 28 17 Megaloptera Sialidae Sialis sp. Odonata Anisoptera Zygoptera Trichoptera Caddisflies. 2 12 Plecotera Stoneflies Coeleoptera Diptera Ceratopogonidae Chironomidae Chironomids 155 142 Gastropoda Snails 22 32 Basommatophora Ancylidae Ferrissia sp. Bivalvia Unionoida 0 16

Table 7. (continued) Chickamauga Reservoir TRM 490.5 TRM 482 Upstream Downstream Species Mean Density Mean Density Veneroida Corbiculidae Corbicula (<=10amm) 37 150 Corbicula (>10mm) 53 83 Sphaeriidae Fingernail clams 300 192 Dreissenidae Dreissena polymorpha Number of samples 10 10 Total Mean Density/SQMeter 653 818 Total area sampled 0.7 0.6 17

Table 8. Recent (1994-2005) Benthic Index Scores Collected as Part of the Vital Signs Monitoring Program at Chickamauga Reservoir Transition (TRM 490.5 and TRM 482) and Forebay Zone (TRM 472.3) Stations. Site

• Reservoir Location 1994 1995 1997 1999 2000 2001 2002 2003 2004 2005 Average Upstream Chickamauga TRM 490.5 33 29 31 31 23 25 23 31 29 31 29 Downstream Chickamauga TRM 482 23 31 27 29 35. 31 29 Downstream Chickamauga TRM 472.3 31 27 29 25 27 27 23 27 27 27 27 Note: No data were collected for 1996 and 1998.

Scores that are considered very poor range from 7-12, poor range from 13-18, fair range from 19-23, good range from 23-29 and excellent range from 30-35. Table 9. Sport Fishing Index Results for Chickamauga Reservoir, 2004 Species 1997 1998 1999 2000 2001 2002 2003 2004 1997-2004 Average SF1 Score Black bass 35 41 25 35 31 34 34 31 33 Smallmouthbass 20 20 24 22 40 32 32 32 28 Spotted bass 20 37 24 40 26 32 32 32 30 Largemouth bass 34 37 34 32 28 36 36 38 34 Bluegill 30 32 33 32 32 31 34 32 Channel catfish 32 29 30 25 33 38 31 Crappie 32 31 31 32 38 42 40 35 Sauger 27 36 32 39 30 31 27 26 31 Striped bass 35 30 30 40 34 31 33 White bass 31 30 30 30 40 32 18

Table 10. Sport Fishing Index Population Quantity and Creel Quantity and Quality Metrics and Scoring Criteria. Metrics Scores 5 10 15 Black bass Population (quantity) TVA electrofishing catch/hour < 15 15-31 > 31 State electrofishing (catch/hour) < 62 62-124 > 124 Creel (quantity)' Anglers (catch/hour) < 0.3 0.3-0.6 > 0.6 BAIT and BITE data < 1.1 1.1-2.3 >2.3 Creel (quality) Pressure (hours/acre) <8 8-16 > 16 Largemouth bass Population (quantity)b TVA electrofishing catch/hour < 13 13-25 > 25 State electrofishing (catch/hour) < 53 53-106 > 106 Creel (quantity) Anglers (catch/hour) < 0.29 0.29-0.58 > 0.58 Creel (quality)

• Pressure (hours/acre) <8 8-16 > 16 Smallmouth bass Population (quantity)

TVA electrofishing catch/hour <4 4-8 > 8 State electrofishing (catch/hour) <8 8-15 > 15 Creel (quantity) Anglers (catch/hour) < 0.1 0.1-0.3 > 0.3 Creel (quality) Pressure.(hours/acre) <8 8-16 > 16 Spotted bass Population (quantity) TVA electrofishing catch/hour <5 5-11 > 11 State electrofishing (catch/hour) < 14 14-27 > 27 Creel (quantity) Anglers (catch/hour) < 0.07 0.07-0.13 > 0.13 Creel (quality) Pressure (hours/acre) < 8 8-16 > 16 19

Table 10. (continued) Metrics Scores 5 10 15 Sauger Population (quantity) Experimental gill net (catch/net night) < 9 917 > 17 Creel (quantity) Anglers (catch/hour) < 0.5 0.5-1 > I Creel (quality) Pressure (hours/acre) < 5 5-10 > 10 Channel catfish Population (quantity) Experimental gill net (catch/net night) <2 2-4 >4 Creel (quantity) Anglers (catch/hour) <.0.3 0.3-0.7 > 0.7 Creel (quality) Pressure (hours/acre) <9 9-19 > 19 aEach worth 2.5, 5.0, and 7.5 points if both data sets are available. bTVA electrofishing only used when state agency electrofishing data is unavailable. 20

Table 11. Sport Fishing Index Population Quality Metrics and Scoring Criteria. Scores 5 10 15 Metrics Population (quality) 1 2 3 PSD < 20 or > 80 20-39 or 61-80 40-60 RSDP (preferred) 0 or > 60 1-9 or 41-60 10-40 RSDM (memorable) 0 or > 25 1-4 or 11-25 5-10 RSDT (trophy) 0 <1 1 W, (Stock-preferred size fish) < 90 > 110 90-110 Table 12. Electrofishing Catch Rate, Mean Weight, Percent H-arvestable, Numbers of Black Bass Greater than Five Pounds, Numbers of Black Bass Greater than Four Pounds and Largest Black Bass Collected, Chickamauga Reservoir Black Bass Surveys, 1995-2005. EF Catch Mean Largest Yea, Rate Weight  % Bass >4 Bass >5 bass r (no./hr.) (lbs.) Harvestable lbs. lbs. (lbs.) 2005 72.6 1.3 36.9 15 9 6.2 2004 40.9 1.3 60.2 13 6 6.6 2003 62.0 1.3 65.8 23 8 6.4 2002 57.4 1.1 59.4 9 4 6.6 2001 34.5 0.8. 45.2 0 0 2.8 2000 34.4 1 51.2 3 0 4.8 1999 10.6 1.3 60.7 3 1 6.1 1998 37.2 1.1 44.5 9 2 6.6 1997 40.2 1 70.1 8 4 8.7 1996 51 1.2 42.6 13 9 7.9 1995 62 1.2 61.8 28 12 8.3 21

Table 13. Black Bass Catch Per Hour Compared to Habitat Types by Location. 0 Habitat Designation Reservoir and Site Good Fair Poor. Chickamauga Harrison Bay 95(4) 57(4). 44(4) Sale Creek 45(4) 70(4) 49(4) Skull Island 93(2) 106(8) 76(2) Watts Bar Blue Springs 67(3) 50(4) 43(5) Caney Creek 61.(4) 47(4) 50(4) Kingston . 51(4) 37(4) 39(4) Watts Bar Dam 69(3) 42(6) 29(3) Catch per hour = number of fish collected per hour

     )= number of transects sampled at each location Table 14. Black Bass Catch Per Hour Compared to Habitat Types by Reservoir.

Habitat Designation Reservoir Good Fair Poor Chickamauga 75 84 52 Watts Bar 61 44 41 Wheeler 79 . 55 65 Catch per hour = number of fish collected per hour 0 22

( Quantity Parameters Quality Parameters Angler~~~

                 . Sucs Smln II PEAgling               Pressure             Species P1opulationl Figure 1. Parameters used to calculate the Sport Fishing Index (SFI).

0 0 23

0 Annual RFAI Scores for Chickamauga 60 50 40 0 30 LL. 20 10 0 1993 - 1994 1995 1996 1997 1998 1999 2000 2001- 2002 2003 2004 2005 Year Figure 2. RFAI scores from sample years between 1993 and 2005. 24

Chickamauga SF1 Scores 1997-2004 60 50 Black, bass 40 ,M Largemouth bass iDSmailmnouth bass, o Spotted bass 0

• Crappie U) 30 U) *Sauger

                                                                                                  .,..,      it  bass...

P Striped bass OBluegilI 20 U Channel catfish 10 0 1997 1998 1999 2000 2001 2002 \ 2003 2004 Year Figure 3. Sport Fishing Index results for Chickamauga Reservoir between 1997 and 2004. 25

0 LENGTH FREQUENCY ALL SITES CHICKAMAUGA 2005 300

• 2*5*

250 w 200

i 160 145-150 z 100 20 F:.':.

i  : ,.104:  : 50 .*i:i::!-:::.i *:i i  : : :* ::::::::::::::::::::

::::::::::::::::::::::::::::r::

0:: 2 4 6 8 10 12 14 16 18 20 22 24 INCH GROUP Figure 4. Chickamauga Reservoir length frequency histogram, (all sites) spring 2005. RSD VALUES (Quality,) MAINSTEM RESERVOIRS SPRING 2005 50 45 40 35 A40 30 25

                                       -*21                                         .          -

20 15 ,1 smbl .S 5Rag 1 10 5

                                        -n                           A      z

C: ,t ii*,i.i

{ Z_ w 0.:.:..:.:.: Reservoir Figure 5. Relative stock density values for Tennessee River Reservoirs. 0 26

0 PSD VALUES MAINSTEM RESERVOIRS SPRING 2005 100 90 80 70 60

%:I 50 40 30 20

                             .3    O~sir-bl PS RrD 10 I                                  f R.:.        r oi.::

ii Ii Figure 6. Proportional stock density values for Tennessee River Reservoirs. CHICKAMAUGA Wr ALL SITES 0 I= Perc.nt -- 2005 A fFs 100 500 80 400 Ii~iiiii

                    !    60 40 20 300 200 100 0
                                .0-..                    12-14

811 15-19 20-24 25 +

Relative Stock Size by Inch Group Figure 7. Chickamauga Reservoir mean relative weights (Wr) for largemouth bass broken out by RSD category and fish numbers. 27

0 Biological Monitoring of the Tennessee River Near Sequoyah Nuclear Plant Discharge 2006 by Dennis S. Baxter Jeffrey W. Simmons May 2007 Tennessee Valley Authority Aquatic Monitoring and Management

         . Knoxville, Tennessee S

Table of Contents S L is t o f T a b le s ............................................................................................................... ................. i List o f F ig u res .................... ............ ................... ............................ ........................ ................ ii A c ro n y m s ................................................................................................................................... iii Introduction .................................................................................................. Methods ...................................................................... 2 F ish C o m m u n ity ..................................................................................................... ................ 2 Benthic Macroinvertebrate Community ............................................................................. 3 Sport Fishing Index ...................................... ......... ... 4 Spring Sport Fish S urvey ............................... ......

                                                                                               .....                       ............................ ......... 4 Results and D iscussion .......................................................................................................                                         5 Fish Com m unity ............................................................................                         ...................................            5 Benthic Macroinvertebrate Community ........................................                                                                                         6
    .Sport Fishing Index ...... :...............................................................................                    .................                     7 Spring Sport Fish Survey .................................................................................................                                           7 L iteratu re C ited ........................................             ...............    ..................................................................          9 List of Tables Table 1.        Scoring Results for the Twelve Metrics and Overall Scores for all RFAI sites sampled in Chickamauga Reservoir, 2006 ..........................                                                                                     10 Table 2.        RFAI Scores Developed Using the RFAI Metrics from Samples Collected during 1993 to 2006, Upstream and Downstream of Sequoyah Nuclear Plant .......... 11 Table 3.        Scoring Criteria for For'ebay, Transition, and Inflow Sections of Upper Mainstem Reservoirs in the Tennessee River System. Upper Mainstem Reservoirs include Chickamauga, Fort Loudoun, Melton Hill, Nickajack, Tellico, and W atts B ar .......................................... I......................................................... 12 Table 4.        Species Listing and Catch Per Unit Effort for Forebay Transects on Chickamauga Reservoir during Fall Electrofishing and Gill Netting, 2006.

(Electrofishing Effort = 300 Meters of Shoreline, Gill Netting Effort = 10 Net-Nig h ts ) .................................................................................................................... 13 Table 5. Species Listing -and Catch Per Unit Effort for the Transition and Inflow Transects on Chickamauga Reservoir during Fall Electrofishing and Gill Netting, 2006. (Electrofishing Effort = 300 Meters of Shoreline, Gill Netting-Effort = 10 Net-Nights) ...................................................................................... 14 Table 6. Individual Metric Ratings and the Overall Benthic Index Field Scores for Upstream (TRM 490.5) and Downstream (TRM 482) Sampling Sites Near Sequoyah Nuclear Plant, Chickamauga Reservoir, 2006 ............................ 16 0Q 1

List of Tables (continued) Table 7. Average Mean Density Per Square Meter of Benthic Taxa Collected at Upstream (TRM 490.5) and Downstream (TRM 482) Sampling Sites Near Sequoyah Nuclear Plant, Chickamauga Reservoir, 2006 .............................. 17 Table 8. Benthic Index Field Scores from Data Collected during 1994-2006 at Chickamauga Reservoir Transition (TRM 490.5) and Forebay (TRM 482.0 and T R M 472.3) S ites . .............................................................................................. 19 Table 9. A Comparison of Benthic Index Scores from Field and Lab Processed Samples at the Upstream (TRM 490.5) and Downstream (TRM 482) Sites from Sequoyah

   -      Nuclear Plant. Scores are only Presented for Years when Field Samples were L ab P ro cessed .........................................................................................................         19 Table 10. Sport Fishing Index Scores for Chickamauga Reservoir, 1997-2005 ............                                                        20 Table 11. Sport Fishing Index Population Quantity, Creel Quantity, Quality Metrics, and Scoring Criteria ..............................................                                                                    21 Table 12. Sport Fishing Index Population Quality Metrics and Scoring Criteria .......                                                         22 Table 13. Electrofishing Catch Rates and Population Characteristics of Black Bass Collected during Spring Sport Fish Surveys on Chickamauga Reservoir,- 1995-2 0 0 6 . ...................................................................................................................... 22 Table 14. Black Bass Catch Per Hour Compared to Habitat Types by Location during Spring Sport-Fish Surveys on Chickamauga Reservoir, 2006 .....................                                                      23 List of Figures Figure 1. Parameters used to calculate the Sport Fishing Index (SFI) ........................ 23 Figure 2. Annual Chickamauga Reservoir RFAI scores for sample years between 1993 an d 2006 ...................................................................................................................       24 Figure3. Sport Fishing Index results for Chickamauga Reservoir between 1997 and 2 00 5 .. ........................................................................................................................ 25 Figure 4. Length frequency distribution for largemouth bass collected from Chickamauga Reservoir (all sites) during the Spring Sport Fish Survey, 2 0 0 6 ........................................................................................................................... 26 Figure 5. Relative stock density values for Tennessee River reservoirs calculated from 2006 Spring Sport Fish Survey samples ..........................................................                                    26 Figure 6. Proportional stock density values for Tennessee River reservoirs calculated from 2006 Spring Sport Fish Survey samples ........................                                                                 27 Figure 7. Chickamauga Reservoir mean relative weights (Wr) for largemouth bass by RSD category and number of fish during 2006 ....... ....................................... 27 ii

Acronyms _1BI Benthic Macroinvertebrate Index BIP Balanced Indigenous Population NPDES National Pollutant Discharge Elimination System PSD Proportional Stock Density QA Quality Assurance RFAI Reservoir Fish Assemblage Index RSD Relative Stock Density z RSDM Relative Stock Density of Memorable-sized RSDP Relative Stock Density of Preferred-sized RSDT Relative Stock Density of Trophy-sized SAHI Shoreline Assessment Habitat Index SFI Sport Fishing Index SQN Sequoyah Nuclear Plant SSS Spring Sport Fish Survey TRM Tennessee River Mile TVA Tennessee Valley Authority VS Vital Signs Wr Relative Weight 0 111

Introduction Section 316(a) of the Clean Water Act specifies that industrial, municipal, and other facilities must obtain permits if their thermal discharges go directly to surface waters. Industries responsible for point-source discharges of heated water can obtain a variance from state water quality standards if the industry can demonstrate compliance with thermal criteria by documenting the maintenance of Balanced Indigenous Populations (BIP) of aquatic life in the vicinity of its discharge. Sequoyah Nuclear Plant's (SQN) current National Pollutant Discharge Elimination.System (NPDES) permit number TN0026450 states, "For Section 316(a), the permittee shall analyze previous and new data to determine whether significant changes have occurred in the plant operation, reservoir operation, or in stream biology that would necessitate the need for changes in the thermal variance." The permittee shall use the Reservoir Fish Assemblage Index (RFAI) to assess Chickamauga Reservoir fish community health. Any apparent declines in the fish community health will be further investigated to discover whether the decline is a valid conclusion and if the decline is real to identify possible sources for the fish community decline. As part of the identification of potential sources for the decline, the instream effects of the discharges made under this permit will be investigated (TDEC 2000). In response to this requirement; Tennessee Valley Authority's (TVA's) Vital Signs (VS) monitoring program (bycus and Meinert 1993) will be used to evaluate areas of Chickamauga Reservoir upstream and downstream of SQN discharge. The purpose of this document is to briefly summarize and provide results of the Calendar Year 2006 monitoring and analyses to the Tennessee Department of Environment and Conservation and compare these results with historical monitoring data. Prior to 1990, TVA conductedreservoir ecological assessments to meet specific needs as they arose. In 1990, TVA instituted a Valley-wide VS monitoring program which is a broad-based evaluation of the overall ecological conditions in major reservoirs. Data are evaluated with a multi-metric monitoring approach utilizing five environmental indicators: dissolved oxygen, chlorophyll, sediment quality, the benthic macroinvertebrate community, and the fish community. When this program was initiated, specific evaluation techniques were developed for each indicator, and these techniques were fine-tuned to better represent ecological conditions. The outcome of this effort was development of multi-metric evaluation techniques for the fish assemblage (i.e., RFAI) and the benthic community (i.e., Benthic Macroinvertebrate Index [BI]). These multi-metric evaluation techniques have proven successful in TVA's monitoring efforts as well as for other federal and state monitoring programs. For consistency, only RFAI analyses between 1993 and 2006 will be utilized. The BI is used primarily to support the RFAI analysis. In the past, the Sport Fishing Index (SFI) was used in support of a thermal variance request at SQN (TVA 1996). The SFI was developed to quantify sport fishing quality for individual sport fish species. The SF1 relies on measurements of quantity and quality aspects of angler success and fish population characteristics. This provides biologists with a reference point to measure the quality of a sport fishery. Comparison of the population sampling parameters and creel results for a particular sport fish species with expectations of these parameters from a high quality fishery (reference conditions) allows for the determination of fishing quality. Indices have been developed for black bass (largemouth, smallmouth, and spotted bass), crappie, sauger, striped bass, bluegill, channel catfish, and white bass. 0 I

In recent years, SFI information has been used to describe the quality of the resident sport

• fishery in conjunction with compliance monitoring, thermal variance requests, and other regulatory issues at TVA nuclear plants in Tennessee. Similar NPDES compliance monitoring programs using the methodologies described above are also being performed at Browns Ferry Nuclear Plant, Colbert and Widows Creek Fossil Plants in Alabama.

The TVA Spring Sport Fish Survey (SSS) is conducted to evaluate sport fish populations in TVA Reservoirs. The results of the survey are used by state agencies to protect, improve, and assess the quality of sport fisheries. Predominant habitat types in the reservoir are surveyed to determine sport fish abundance. In addition to accommodating TVA and state databases, this surveying method aligns with TVA Watershed Team and TVA's Reservoir Operations Study objectives. Sample sites are selected using the shoreline habitat characteristics employed by the Watershed Teams. Thesurvey targets three species of black bass (largemouth, smallmouth, and spotted bass) and black and white crappie. These species are the predominant sport fish sought after by fisherman. Methods Fish Community Reservoirs are typically divided into three zones for VS monitoring - inflow, transition, and forebay. The inflow zone is generally in the upper reaches of the reservoir and is riverine in nature; the transition zone or*mid-reservoir is the area where water velocity decreases due to increased cross-sectional area; and the forebay is the lacustrine area near the dam. The Chickamauga Reservoir inflow zone sample site is located at Tennessee River Mile (TRM) 529.0, the transition zone sampling site is located at TRM 490.5, and the forebay zone sampling sites are located at TRM 482.0 and 472.3. The transition zone sampling site, which is located approximately 7.2 river miles upstream of the SQN discharge, is-used as a control site to provide upstream data for 316(a) thermal variance studies conducted during sample years from 1993 to 2006. The downstream station is located at TRM 482.0 and has been sampled each year from 1999 to 2006 to monitor Chickamauga Reservoir aquatic communities in close proximity to the SQN thermal effluent. Previously, the downstream station was located at TRM 472.3 during sample years from 1993 to 1997. Sampling effort consisted of fifteen 300-meter electrofishing runs (approximately 10 minute duration) and ten experimental gill net sets (five 6.1 meter panels with mesh sizes of 2.5, 5.1, 7.6, 10.2, and 12.7 cm) per site. Attained values for each of the 12 metrics were compared to reference conditions for transition zones of lower mainstream Tennessee River reservoirs and assigned scores based upon three categories hypothesized to represent relative degrees of . degradation: least degraded-- 5; intermediate - 3; and most degraded- 1. These categories are based on "expected" fish community characteristics in the absence of human-induced impacts other than impoundment. Individual metric scores for a site are summed to obtain the RFAI score. Comparison of the attained RFAI score from the potential impact zone to a predetermined criterion has been suggested as a method useful in identifying presence of normal community structure and function and hence existence-of a BIP. For multi-metric indices, two criteria ýhave been suggested to ensure a conservative screening for a BIP. First, if an RFAI score reaches 70 percent of the highest attainable score (adjusted upward to include sample variability), and second, if fewer than half of RFAI metrics potentially influenced by thermal discharge receive a 2

low (1) or moderate (3) score, then normal community structure and function would be present Q indicating that a BIP existed. Under these conditions, the heated discharge would meet screening criteria and no further evaluation would be needed. Potential RFAI scores range from 12 to 60. Ecological health ratings ("Very Poor" 12-21, "Poor" 22-31, "Fair" 32-40, "Good'.' 41-50, or "Excellent" 51-60) are then applied to scores.. As discussed in detail below, the average variance for RFAI scores inTVA reservoirs is 6 (+ 3). Therefore, any location that attains an RFAI score of 45 (42 + our sample variance of 3) or higher would be considered to demonstrate a BIP. It must be stressed that scores below this endpoint do not necessarily reflect an adversely impacted fish community. The endpoint is used to serve as a conservative screening level; for example, any fish community that meets these criteria is obviously not adversely impacted. RFAI scores below this level would require a more in-depth look to determine if a BIP exists. If.a score below this criterion is obtained, an inspection of individual RFAI metric results would be an initial step to help identify if SQN operation is a contributing factor. This approach is appropriate if a validated multi-metric index is being used and scoring criteria applicable to the zone of study are available. Additionally, upstream/downstream site comparisons can be used to identify if SQN operation is adversely

• affecting the downstream fish community. A similar or higher RFAI score at the downstream.

station compared to the upstream (control) station is used as one basis for determining presence/absence of SQN operational impacts on the resident fish community. Definition of "similar" is integral to accepting the validity of these interpretations. The Quality Assurance (QA) component of VS monitoring deals with .how well the RFAI scores can be repeated and is accomplished by collecting a second set of samples at 15-20 percent of the stations each year. Experience to date with the QA component of VS shows that the O comparison of RFAI index scores from 54 paired sample sets collected over a seven year period.ranged from 0 to 18 points, the 7 5 th percentile was 6, the 9 0 th percentile was 12. The mean difference between these 54 paired scores is 4.6 points with 95 percent confidence limits of 3.4 and 5.8. Based on these results, a difference of 6 points or less is the value selected for defining "similar", scores between upstream and downstream fish communities. That is, if the downstream RFAI score is within 6 points of the upstream score, the communities will be considered similar, It is important to bear in mind that differences greater than 6 points can be expected simply due to method variation (25 percent of the QA paired sample sets exceeded that value). When this occurs, a metric-by-metric examination will be conducted to determine what caused the difference in scores and the potential for the difference to be thermally related. Benthic Macroinvertebrate Community Ten benthic grab samples were collected at equally spaced points along a transect extending from the right descending bank to the left descending bank at each site. A Ponar sampler was used for most samples but a Peterson samplerwas used when larger substrate was' encountered. Collection and processing techniques followed standard VS procedures. Bottom sediments werewashed on a 533p screen; organisms were then picked from the screen and remaining substrate and identified to Order or Family level in the field using no magnification. Benthic community results were evaluated using seven community characteristics or metrics. Results for each metric were assigned a rating of 1, 3, or 5 depending upon how they compared to reference conditions developed for VS sample sites. The ratings for the seven metrics were summed to produce a total benthic score for each sample site. Each reservoir section (inflow, transition, or forebay) differs in their maximum potential for benthic diversity; thus, the criteria for assigning metric ratings were adjusted accordingly such that the total benthic scores from sites at different reservoir sections are comparable. Potential scores ranged from 7 to 35. Ecological 3

health ratings ("Very Poor" 7-12, "Poor" 13-18, "Fair" 19-23, "Good" 24-29, or "Excellent" 30-35) S are then applied to scores. A similar or higher benthic index score at the downstream site compared to the upstream site is used as basis for determining absence of impact on the Chickamauga Reservoir benthic macroinvertebrate community related to SQN's thermal discharge. The QA component of VS monitoring shows that the comparison of benthic index scores from 49 paired sample sets collected over a seven year period ranged from 0 to 14 points; the 75 h percentile was 4 and the 9 0 th percentile was 6. The mean difference between these 49 paired scores is 3.1 points with 95 percent confidence limits of 2.2 and 4.1. Based on these results, a difference of 4 points or less is the value selected for defining "similar" scores between upstream and downstream benthic communities: That is, if the downstream benthic score is within 4 points of the upstream score, the communities will be considered similar and it will be concluded that SQN has had no effect. Once again, it is important to bear in mind that differences greater than 4 points can be expected simply due to method variation (25 percent of the QA paired sample sets exceeded that value). When. this occurs, a metric-by-metric examination will be conducted to determine what caused the difference in scores and the potential for the difference to be thermally related. Sport Fishing Index Calculations described by Hickman (2000) were used to compare SF1 values for selected quantity and quality parameters from creel and population samples to expected values that would occur ina good or high quality fishery. Quantity parameters include angler success and catch per unit effort from standard population samples (electrofishing, trap, and experimental gill netting). Population quality is based on measurement of five aspects of each resident sport fish community. Four of these aspects address size structure (proportional number of fish in each length group) of the community, Proportional Stock Density (PSD), Relative Stock Density of Preferred-sized fish (RSDP), Relative Stock Density of Memorable-sized fish (RSDM), and : Relative Stock Density of Trophy-sized fish (RSDT) (Figure 1). Relative weight (Wr), a measure of the average condition of individual fish makes up the fifth population quality aspect. As described by Hickman (2000), observed values were compared to reference ranges and assigned.a corresponding numerical value. The SFI value is calculated by adding the scores for quantity and quality from existing data and multiplying by two when only creel or population data are available. Species received a low score when insufficient numbers of individuals were captured to reliably determine proportional densities or relative weights for particular parameters. SFI scores are typically compared to average Tennessee Valley reservoir scores;

   -however, Valley-wide scores are unavailable from natural resource agencies. Therefore, Chickamauga Reservoir fish species scores will be compared to previous years. The 2006 Tennessee Wildlife Resources Agency gill netting and creel data were not available for.

analyses before this report was submitted; therefore 2005 SFI data were used. Additionally, 2005 SFI values were only calculated for black bass species in Chickamauga Reservoir due to insufficient data for other sport fish species. Spring Sport Fish Survey A Spring Sport Fish Survey was conducted on Chickamauga Reservoir March 21-23, 2006. During the sampling period, water levels on Chickamauga Reservoir were 676.8 to 677.3 msl (summer pool level is 682.5 msl). Sampling was conducted using a boat mounted electrofishing unit at a total of twelve sites at, Harrison Bay, Ware Branch, and Sale Creek. Sampling effort at l each site consisted of thirty minutes of continuous electrofishing in the littoral zones of 4

prominent habitat types present. After being stunned, fish were collected with dip nets, counted, weighed, measured, and then released unharmed. Results of the SSS. monitoring were calculated using Shoreline Assessment Habitat Index (SAHI), Relative Stock Density (RSD), PSD, and Wr. Habitat type is evaluated using the SAHI metric and is a critical component incorporated into the SSS. The resultant habitat designations ("Good", "Fair", and "Poor") are correlated to black bass abundance (numbers/hour). RSD is the number of fish greater than a minimum preferred length in a stock divided by the number of fish greater than or equal to a minimum stock size. PSD is the number of fish greater than or equal to a minimum quality length in a sample divided by the number of fish greater than or equal to a minimum stock length. Wr is an index that quantifies fish condition and the preferred range value is 90-105% for moderate density bass populations such as those found in the Tennessee Valley latitudes. Results and Discussion Fish Community RFAI fish data collected during autumn 2006 from TRM 490.5 upstream from SQN resulted in a RFAI score of 47 ("Good"), while the downstream site at TRM 482 scored 37 ("Fair") (Table 1). Although the downstream site scored "Fair", this site has averaged "Good" over all sample years with a average score of 43 (72 percent of the maximum score) (Table 2). Because the downstream site scored ten points lower than the upstream site, individual RFAI metrics were examined to evaluate this difference and to determine if this score was indicative of thermal effects (refer to Table 3 for scoring criteria for the twelve RFAI metrics). Species richness and composition metrics constituted seven points of the ten point score difference (Table 1). The total number of species at the upstream site was 31, compared to 27 at the downstream site, which resulted in a two point scoring difference for the metric"Number of species". During 2006, six 'species were collected at the upstream site that were not found at the downstream site (smallmouth bass, warmouth, northern hog sucker, sauger, white bass, and chestnut lamprey) and two species were collected at the downstream site that were not encountered at the upstream site (western mosquitofish and longnose gar) (Tables 4 and 5). Although more species were collected at the upstream site, four of the six species found only at the upstream site were collected in low numbers (1 sauger, 1 northern hog sucker, 1 chestnut lamprey, and 8 white bass)! The single northern hog sucker collected at the upstream site resulted in this site scoring a total of four points higher than the downstream site for two metrics, "Number of benthic invertivores" and "Number of intolerant species", and influenced the higher score for the metric "Number of species". Three benthic invertivore species were collected at the downstream site while four species, including the northern hog sucker, were found at the upstream site, resulting in a two point score difference (Table 1). Three species considered intolerant were collected at the downstream site while 5 species were found at the upstream site, including smallmouth bass and'the single northern hog sucker, resulting in a two point difference. Although no smallmouth bass were collected at TRM 482 downstream from SQN, only 18 individuals were collected at the upstream site during 2006 RFAI sampling. Additionally, of the 708 black bass collected during the 2006 SSS in Chickamauga Reservoir, only 22 were smallmouth bass; two of the three SSS sample sites were located above SQN. The lack of smallmouth bass in the RFAI sample at TRM 482 is most likely related to the scarcity of physical habitat preferred by smallmouth bass rather than to thermal effects. 5

The downstream site (TRM 482) scored one point lower than the upstream site (TRM 490.5) for l each of the metrics "Percent tolerant individuals", "Percent omnivores", and "Average number W 'per run" because of a lower catch rate in gill net samples at the downstream site (Table 1). The electrofishing catch rate at the downstream site was higher than the upstream site, and overall, more fish were actually collected at the downstream site than at the upstream site (Tables 4 and 5). Higher numbers of tolerant individuals and omnivores were collected in gill nets at the upstream site, but since the gill net catch rate was higher, the percentage of tolerant individuals and omnivores in the sample was lower thanthe downstream site, giving it a higher score. As discussed above, primary factors influencing the higher upstream score were: the collection of a single northern hog sucker (which greatly influenced three metrics); the collection of a few additional species (each primarily consisting of one individual); and a higher gill net catch rate. Examination of the factors influencing individual metrics indicates that the fish community composition is not considerably different between the upstream and downstream sites even

      *though the scores are significantly different. Furthermore, six of the eight sample years have scored "Good" at the downstream site (Figure 2). If the score at the downstream site continues to decline in subsequent samples, further investigation may be required.

It is important to note that the upstream site is scored with transition criteria and the downstream site is scored using forebay criteria (Table 3). More accurate comparisons can be made between sites that are located in the same reservoir zone (i.e., transition to transition). Due to the location of SQN, it is not possible to have an upstream and downstream site within the same reservoir zone. SQN is located at the downstream end of the transition zone on Chickamauga Reservoir; therefore the downstream site is located in the upstream section of the forebay. The physical and chemical composition of a forebay is different than that of a

• transition; consequently, inherent differences exist among the aquatic communities (e.g.

species diversity is often higher ,in a transition than a forebay zone). RFAI scores (Table 1, Figure 2) and electrofishing and gill netting catch rates (Tables 4 and 5) are presented for Chickamauga Reservoir inflow and forebay sites (TRM 529 and 472.3) to provide an overview of ecological health throughout the reservoir; however, aquatic communities at these sites are not affected by SQN temperature effects and are not used to determine BIP in relation to SQN. Both of these-sites scored "Good" during 2006. Benthic Macroinvertebrate Community Benthic macroinvertebrate data collected during autumn 2006 from TRM 490.5 upstream from SQN resulted in a BI score of 27 ("Good"), while the downstream site at TRM 482 scored 31 ("Excellent") (Table 6). Table 7 provides density by taxon from the 2006 samples at these sites. With the exception of the 2000 sample, the BI scores have remained in the "Good" to "Excellent" ecological health range for all sampling seasons at both sites (Table 8). These data indicate that a healthy benthic macroinvertebrate community exists in both the upstream and downstream vicinity of SQN and that the plant is not adversely impacting this fauna. Data collected in Chickamauga Reservoir forebay (TRM 472.3) resulted in a BI score of 29 "Good". This site is located 11 river miles downstream of SQN and sampling results should not reflect temperature effects from the plant. This site is included to provide additional data. on the downstream health of the benthic macroinvertebrate community (Table 8). 6

To ensure data integrity, samples collected and identified in the field at-the SQN monitoring

• sites. (TRM 490.5 and TRM 482) were also identified in the laboratory by an independent consultant. The average Benthic Index scores during years when a sample was both field and lab processed were similar for both sites (Table 9). These results indicate that scores based on field-processed samples provide an acceptable representation of scores based on lab-processed samples. Therefore, during future monitoring, samples will be lab processed one out of every five years in a permit cycle instead of every year.

Sport Fishing Index SF1 scores for Chickamauga Reservoir during 2005 were only calculated for black bass species (largemouth, smallmouth, and spotted) due to insufficient data to accurately calculate SFI scores for other sport fish species. Largemouthand spotted bass scored higher than the 'nine year average during 2005, while smallmouth bass scored 2 points lower than the nine year average (Table 10, Figure 3). Overall, the nine year average score for black bass was the same as the 2005 score (Table 10). Tables 11 and 12 illustrate SFI scoring criteria for population metrics and creel quantity and quality. Spring Sport Fish Survey A total of 18 hours of electrofishing resulted in collection of 608 largemouth bass, 78 spotted bass, and 22 smallmouth bass; of these, 72 percent were harvestable size (>_10 inches). Overall catch rate (39.4 fish/hour) was substantially less than the 2005 survey (72.6 fish/hour), . but was similar to the average catch rate from all twelve sample years (Table 13). The largest black bass collected was a 7.1 pound largemouth bass taken from Sale Creek. Large bass were well represented with 39 bass greater than three pounds, 14 greater than four pounds, and 7 over five pounds. The three-pound category showed an increase of 50 percent over 2005 results, while the four and five-pound categories remained constant. Almost half of the largemouth bass collected were in the 10-13 inch size class (Figure 4). Fish >14 inches comprised 19 percent of the overall sample. All size classes up to 21 inches were represented in the population. Habitat type is derived from the Shoreline Assessment Habitat Index (SAHI) which was developed by TVA's Resource Stewardship Program. The resultant habitat designations (good, fair, and poor) are correlated to black bass abundance (numbers/hour). Among the three areas sampled during 2006, the correlations of habitat type to black bass abundance at Harrison Bay were positive while bass collected at Sale Creek and Skull Island showed some variability among'habitat types,, i.e., the catch rates (abundance) did not align with the habitat designation types (Table 14). The following results describe the quality and condition of black bass collected in Chickamauga Reservoir during'spring 2006: The RSD value (22) fell within the desirable range (10-25) (Figure 5). The PSD value (57) was also within the preferred range (40-70) (Figure 6). Wr values shown in Figure 7 are designated by inch groups which reflect the classical categories, i.e., 0-7 = substock, 8-11 = stock, 12-14 = quality, 15-19 = preferred, 20-24 = memorable and 25+ = trophy. All categories fell within the desired range, which reflects excellent condition of black bass in all size groups of the population. 7

Only 32 crappie (29 black crappie and 3 white crappie) were collected during the survey.

• h Crappie were collected predominantly from tree tops, stumps, and other physical structures in s

Shallow water. Optimum water temperatures for crappie spawning occurred earlier in the spring of 2006 which may have been a factor affecting the catch rate. 8

Literature Cited Dycus, D. L. and D. L. Meinert. 1993. Reservoir Monitoring, Monitoring and Evaluation of Aquatic Resource Health and Use Suitability in Tennessee Valley Authority Reservoirs. Tennessee Valley Authority, Water Resources, Chattanooga, Tennessee, TVA/WM-93/15. Hickman, G. D. 2000. Sport Fish Index (SFI), A Method to Quantify Sport Fishing Quality. Environmental Science & Policy 3 (2000) S117-S125. Tennessee Department of Environment and Conservation. 2000. Draft NPDES Permit Number TN0026450. Tennessee Valley Authority. 1996. A Supplemental 316(a) Demonstration for Alternative Thermal Discharge Limits for Sequoyah Nuclear Plant, Chickamauga Reservoir, Tennessee. Tennessee Valley Authority, Engineering Laboratory, Norris, TN. WR96-1 145. 87 pp. 9

0 0 Table 1. Scoring Results for the Twelve Metrics and Overall Scores for all RFAI sites sampled in Chickamauga Reservoir, 2006. Forebay Inflow TRM 482.0 TRM 529.0 Downstream SUe Metric Obs Score Obs Score A. Species richness and composition

1. Number of species 27 3 27 3

2. Number 6f centrarchid species 6 5 6 5

3. Number of benthic invertivores 3' 1 5 3

4. Number of intolerant species 3 3 6 5

5. Percent tolerant individuals electrofishing 72.4 0.5 65.3 1 gill. netting 29.6 0.5

6. Percent dominance by one species electrofishing 33.6 1.5 29.1 3 gill netting 22.5 1.5

7. Number non-native species electrofishing 0 2.5 0.1 5 gill netting 0 2.5

8. Number of top carnivore species 8 .5 9 5 B. Trophic composition

9. Percent top carnivores electrofishing 6.5 1.5 9 1 gill netting 40.8 1.5

10. Percent omnivores electrofishing 24.6 1.5 31.5 3 gill netting 47.9 0.5 10

Table 1. (continued) 0 0 Forebay Inflow TRM 482.0 TRM 529.0 Downstream Site Metric Obs Score Obs Score C. Fish abundance and health 1,1 Averag v~~ ,,,u beri*i~ u ru3lcro uuu

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critriaFAI Refe cors: to able3). V ry P or 1-*21 Poo 22-1, F ir 2-40 Goo.41- .,.Ecel. nt.5 -60 Table 2. RFAI Scores Developed Using the RFAI Metrics from Samples Collected during 1993 to 2006, Upstream and Downstream of Sequoyah Nuclear Plant. Station Reservoir Location 1993 1994 1995 1997 1999 2000* 2001 2002* 2003 2004* 2005 2006* 1993-2006 Average Upstream Chickamauga TRM 490.5 49 40 46 39 45 46 45 51 42 49 48 47 46 (Good) Downstrea Chickamauga TRM 482.0 41 48 46 43 45. 41 39 37 43 m (Good) Downstrea Chickamauga TRM 472.3 44 44 47 39 45 45 48 46 43 43 46 44 45 m (Good)

     *The 2000, 2002, 2004, and 2006             sample years were not part of the VS monitoring program, however the same methodology was applied.

1I

Table 3. Scoring Criteria for Forebay, Transition, and Inflow Sections of Upper Mainstem Reservoirs in the Tennessee River System. Upper Mainstem Reservoirs include Chickamauga, Fort Loudoun, Melton Hill, Nickajack, Tellico, and Watts Bar. Scoring Criteria Forebay Transition Inflow Metric Gear 1 3 5 1 3 5 1 3 5 A. Species richness and composition

1. Total species Combined <14 14-27 >27 <15 15-29 >29 <14 14-27 >27

2. TotalCentrarchid species Combined <2 2-4 >4, <2 2-4 >4 <3 3-4 >4

3. Total benthic invertivores Combined <4 4-7 >7 <4 4-7 >7 <3 3-6 >6

4. Total intolerant species Combined <2 2-4 >4 <2 2-4 >4 <2 2-4 >4

5. Percent tolerant individuals Electrofishing >62% 31-62% <31% >62% 31-62% <31% >58% 29-58% <29%

Gill netting >28% 14-28% <14% >32% 16-32% <16%

6. Percent dominance byl1 species Electrofishing >50% 25-50% <25% >40% 20-40% <20% >46% 23-46% <23%

Gill netting >29% 15-29% <15% .>28% 14-28% <14%

7. Percent non-native species Electrofishing >4% 2-4% <2% >6% 3-6% <3% >17% 8-17% <8%

Gill netting >1.6% 8-16% <8% >9% 5-9% <5%

8. Total top carnivore species Combined <4 4-7 >7 <4 4-7 >7 <3 3-6 >6 B. Trophic composition

9. Percent top carnivores Electrofishing <5% 5-10% >10% <6% 6-11% >11% <11% 11-22% >22%

Gill netting <25% 25-50% >50% <26% 26-52% >52%

10. Percent omnivores Electrofishing >49% 24-49% <24% >44% 22-44% <22% >55% 27-55% <27%

Gill netting >34% 17-34% <17% >46% 23-46% <23% C. Fish abundance and health

11. Averagernumber per run Electrofishing <121 121-241 >241 <105 105-210 >210 <51 51-102 >102 Gill netting <12 12-24 >24 <12 12-24 >24

12. Percent anomalies Electrofishing >5% 2-5% <2% >5% 2-5% <2% >5%. 2-5% <2%

Gill netting >5% 2-5% <2% >5% 2-5% <2% 12

Table 4. Species Listing and Catch Per Unit Effort for Forebay Transects on Chickamauga S Reservoir during Fall Electrofishing and Gill Netting, 2006. (Electrofishing Effort = 300 Meters of Shoreline, Gill Netting Effort = 10 Net-Nights) Forebay TRM 472.3 Forebay TRM 482.0 El ectrofishing Electrofishing Gill Netting Electrofishing Electrofishing Gill Netting Catch Rate Catch Rate Catch Rate Catch Rate Catch Rate Catch Rate Common Name Per Per Per Per Per Per Run Hour Net Night Run Hour Net Night Spotted aar - 0.13 0.58 Longnose gar 0.20 Skipjack herring 3.90 2.10 Gizzard shad 3.47 14.53 6.50 12.53 54.65 3.20 Threadfin shad 5.53 23.18 0.33 1.45 Hybrid shad 0.40 0.50 Common carp 0.27 1.12 0.10 Golden shiner 0.53 2.23 0.50 0.27 1.16 0.20 Emerald shiner 0.67 2.79 1.73 7.56 Spotfin shiner 0.47 1.96 2.53 11.05 Bluntnose minnow 2.00 8.72 Bullhead minnow 0.13 0.58 Spotted sucker 0.20 0.84 0.20 0.13 0.58 0.10 Blue catfish 0.50 1.50

/nnel    catfish-           0.33            1.40          0.20          0.20             0.87        1.40
*Iead catfish               0.07            0.28          0.40          0.13             0.58        0.30 Western mosquitofish                                                     0.07             0:29 Yellow bass                                                3.20                                       0.90 Warmouth                     0.27            1.12 Redbreast sunfish           14.33           60.06                        4.67           20.35 Green sunfish                0.47            1.96                        0.07             0.29 Bluegill                    20.60          ~86.31          0.10        20.47            89.24         0.50 Longear sunfish              0.67            2.79                        0.73             3.20 Redear sunfish               2.20            9.22          0.90          7.47           32.56         0.70 Hybrid sunfish               0.07            0.28 Smallmouth bass              1.00            4.19 Spotted bass                 1.13            4.75          4.10         2.00              8.72        0.90 Largemouth bass              1.00            4.19          0.30          1.53             6.69        0.10 White crappie                                              0.10 Black crappie.                                                          0.13              0.58        1.30 Logperch                                                                 1.00             4.36 Freshwater drum              0.40            1.68          0.50         0.13              0.58        0.30 Brook silverside             0.20           0.84 r, rvq                     -I,

• Inland silverside 1 Of)

I .LAJ .JA.J~J - I £...J.J 1 1 I I M; Total 55.15 231.03 26.60 60.91 265.69 14.20 Number Samples 15 10 15 10 Number Collected 827 266 914.00 142 ,ies Collected 23 17 23 16 13

Table 5. Species Listing and Catch Per Unit Effort for the Transition and Inflow Transects on Chickamauga Reservoir during Fall Electrofishing and Gill Netting, 2006. (Electrofishing Effort = 300 Meters of Shoreline, Gill Netting Effort = 10 Net-Nights) Transition TRM 490.5 Inflow TRM 529.0 Electrofishing Electrofishing Gill Netting Electrofishing Electrofishing Catch Rate Catch Rate Catch Rate Catch Rate Catch Rate Common Name Per Per Per Per Per Run Hour Net Night Run Hour Longnose gar - - 0.13 0.58 Spotted gar 0.07 0.32 - 0.13 0.58 Skipjack herring - - 3.10 - Gizzard shad 17.33 84.14 6.30 17.93 77.52 Threadfin shad 3.87 18.77 0.10 0.07 0.29 Common carp - - - 0.07 0.29 Golden shiner 0.60 2.91 - - Emerald shiner \ 1.53 7.44 - 1.27 .5.48 Spotfin shiner 0.40 1.94 - .2.93 12.68 Bluntnose minnow 0.07 0.32 - - Bullhead minnow 0.07 0.32 .--- Smallmouth buffalo - --- Black buffalo - -

• Northern hog sucker 0.07 0.32 Spotted sucker 0.33 1.62 0.10 0.20 0.86 Black redhorse -- - 0.40 1.73 Golden redhorse - 0.80 3.46 Blue catfish - - 0.10 0.07 0.29 Channel catfish 0.27 1.29 0.40 1.33 5.76 Flathead catfish 0.20 0.97 - 0.47 2.02 White bass - 0.80 -

Yellow bass 5.50 0.53 2.31 Striped bass - - Rock bass , - 0.07 0.29 Warmouth 0.07 0.32 Redbreast sunfish 4.33 21.04 1.27 5.48 Green sunfish 0.07 0.32 0.20 0.86 Bluegill 11.40 55.34 16.67 72.05 Longear sunfish 1.00 4.85 1.67 7.20 Redearsunfish 2.80 13.59 - 5.53 .23.92 Smallmouth bass 1.13 5.50 0.10 0.67 2.88 Spotted bass 1.60 7.77 1.00 2.13 9.22 Largemouth bass 0.27 1.29 0.40 1.07 4.61 White crappie -- - , Black crappie 0.80 3.88 1.80 0.33 1.44 14

Table 5. (continued) Transition TRM 490.5 Inflow TRM 529.0 Electrofishing Electrofishing Gill Netting Electrofishing Electrofishing Catch Rate Catch Rate Catch Rate Catch Rate Catch Rate Common Name Per Per Per Per Per Run Hour Net Night Run Hour Yellow perch - - Logperch 0.27 1.29 1.47 6.34 Sauger - - 0.10 -- Freshwater drum 0.20 0.97 0.60 1.27 5.48 Brook silverside -- - 1.00 4.32 Inland silverside 0.40 1.94 - 2.00 8.65 Chestnut lamprey - - 0.10 - Total 49.15 238.46 25 61.68 266.59 Number Samples 15 10 15 Number Collected 737 250 925 Species Collected 25 17 28 15

Table 6. Individual Metric Ratings and the Overall Benthic Index Field Scores for Upstream (TRM 490.5) and Downstream (TRM 482) Sampling Sites Near Sequoyah Nuclear Plant, Chickamauga Reservoir, 2006. TRM 490.5 TRM 482 Upstream Downstream Metric Obs Rating Obs Rating

1. Average number of taxa 5.4 5 5 5

2. Proportion of samples with long-lived organisms. 0.8 5 0.9 5

3. Average number of EPT taxa 0.5 3 0.7 3

4. Average proportion of oligochaete individuals 2.5 5 17.3 3

5. Average proportion of total abundance comprised by -83.1 3 *77.2 5 the two most abundant taxa

6. Average density excluding chironomids and 223.3 1 266.7 5 oligochaetes

7. Zero-samples- proportion of samples containing no 0 5 0 5 organisms Benthic Index Score 27 31 Good Excellent

• TRM 490.5 scored with transition criteria,,TRM 482 scored with forebay criteria.

Benthic Index Scores: Very Poor 7-12, Poor 13-18, Fair 19-23, Good 24-29, Excellent 30-35 16

Table 7. Average Mean Density Per Square Meter of Benthic Taxa Collected at Upstream S (TRM 490.5) and Downstream (TRM 482) Sampling Sites Near Sequoyah Nuclear Plant, Chickamauga Reservoir, 2006. Chickamauga Reservoir TRM 490.5 TRM 482 Upstream Downstream Species Mean Density Mean Density Tubellaria Tricladida Planariidae 3 Oligocheata Oligochaetes 15 85 Hirudinea 15 67 Crustacea Amphipoda 15 Isopoda Insecta Ephermeroptera Mayflies 2 Ephemeridae Hexagenia (<10 mrm) .3 2 Hexagenia (>10 mm) 15 22 Megaloptera Sialidae Sialis sp. 2 Odonata Anisoptera Zygoptera

            *Trichoptera Caddisflies                                       5 Plecotera Stoneflies Coeleoptera Diptera Ceratopogonidae Chironomidae Chironomids                    322               113 Gastropoda Snails                          10               20 Basommatophora Ancylidae Ferrissia sp..

Bivalvia Unionidae Mussels 17

Table 7. (continued) Chickamauga Reservoir TRM 490.5 TRM 482 Upstream Downstream Species Mean Density Mean Density Veneroida Corbiculidae Corbicula (<10mm) 28. 57 Corbicula (>10mm) 17 .57 Sphaeriidae Fingernail clams 133 17 Dreissenidae Dreissena polymorpha Number of samples 10 10 Total Mean Density/SQ Meter 560 465 Total area sampled (SQ Meters) 0.6 0.6 ( 18

Table 8. Benthic Index Field Scores from Data Collected during 1994-2006 at Chickamauga Reservoir Transition (TRM 490.5) and Forebay (TRM 482.0 and TRM 472.3) Sites. Site Reservoir Location 1994 1995 1997 1999 2000 2001 2002 2003 2004 2005 2006 Average Upstream Chickamauga TRM 490.5 33 29 31 31 23 25 25 31 31 31 27 29 Downstream Chickamauga TRM 482.0 23 31 29 29 33 31 31 30 Downstream Chickamauga TRM 472.3 31 27 29 25 27 27 21 27 29 27 29 27 Benthic Index Scores: Very Poor 7-12, Poor 13-18, Fair 19-23, Good 24-29, Excellent 30-35 Note: No data were collected for 1996 and 1998. Table 9. A Comparison of Benthic Index Scores from Field and Lab Processed Samples at the Upstream (TRM 490.5) and Downstream (TRM 482) Sites from Sequoyah Nuclear Plant. Scores are only Presented for Years when Field Samples were Lab Processed. Site TRM Score 2000 2001 2002 2003 2004 2005 2006 Average Upstream 490.5 Field 23 25 25 31 31 31 27. 28 Lab, 21 19 23 27 29 31 23 25 Downstream 482 Field 23 31 29 29 33 31 31 30 Lab 27 29 27 33 35 33 33 31 19

Table 10. Sport Fishing Index Scores for Chickamauga Reservoir, 1997-2005. Species 1997 1998 1999 2000 2001 2002 2003 2004 2005 1997-2005 Average SFI Score Black bass 35 41 25 35 31 34 34 31 33 33 Smallmouth bass 20 20 24 22 40 32 32 32 26 28 Spotted bass 20 37 24 40 26 32 32 32 36 31 Largemouth bass 34 37 34 32 28 36 36 38 36 35 Bluegill 30 - 32 33 32 32 31 34 - 32 Channel catfish - -32 29 30 25 33 38 31 Crappie 32 31 31 32 38 42 40 35 Sauger 27 36 32 39 30 .31 27 26 31 Striped bass 35 - 30 30 40 34 31 - 33 White bass . 31 30 30 30 40 32 20

Table 11. Sport Fishing Index Population Quantity, Creel Quantity, Quality Metrics, and

• Scoring Criteria.

Scores Metrics 5 10 15 Black bass Population (quantity) TVA electrofishing catch/hour < 15 15-31 > 31 State electrofishing (catch/hour) < 62 62-124 > 124 Creel (quantity)' Anglers (catch/hour) < 0.3 0.3-0.6 > 0.6 BAIT and BITE data < 1.1 1.1-2.3 > 2.3 Creel (quality) Pressure (hours/acre) <8 8-16 > 16 Largemouth bass Population (quantity)b TVA electrofishing catch/hour < 13 13-25 > 25 State electrofishing (catch/hour) < 5,3. 53-106 > 106 Creel (quantity) Anglers (catch/hour) < 0.29 0.29-0.58 > 0.58 Creel (quality) Pressure (hours/acre) <8 8-16 > 16 Smallmouth bass

• Population (quantity)

TVA electrofishing catch/hour <4 4-8 >8 State electrofishing (catch/hour) <8 8-15 > 15 Creel (quantity) Anglers (catch/hour) < 0.1 0.1-0.3 > 0.3 Creel (quality) Pressure (hours/acre) <8 8-16 > 16 Spotted bass Population (quantity) TVA electrofishing catch/hour < 5 5-11 > 11 State electrofishing (catch/hour) < 14 14-27 > 27 Creel (quantity) Anglers (catch/hour). < 0.07 0.07-0.13 > 0.13 Creel (quality) Pressure (hours/acre) < 8 8-16 > 16 Sauger Population (quantity) Experimental gill net (catch/net night) <9 9-17 > 17 Creel (quantity) Anglers (catch/hour) < 0.5 0.5-1 >1 Creel (quality) Pressure (hours/acre) <5 5-10 > 10 21

Table 11. (continued) 0 Metrics 5 Scores 10 15 Channel catfish Population (quantity) Experimental gill net (catch/net night) <2 2-4 >4 Creel (quantity) Anglers (catch/hour) < 0.3 0.3-0.7 .> 0.7 Creel (quality) Pressure (hours/acre) <9 9-19 > 19 aEach worth 2.5, 5.0, and 7.5 points if both data sets are available. bTVA electrofishing only used when state agency electrofishing data are unavailable. Table 12. Sport Fishing Index Population Quality Metrics and Scoring Criteria. Scores Metrics 5. 10 15 Population (quality) 1 2 3 PSD < 20 or > 80 20-39 or 61-80 40-60 RSDP (preferred) 0 or > 60 1-9 or 41-60 10-40 RSDM (memorable) 0 or > 25 1-4.or 11-25 5-10 RSDT (trophy) 0 < 1 _1 Wr (Stock-preferred size fish) < 90 > 110 90-110 Table 13. Electrofishing Catch Rates and Population Characteristics of Black Bass Collected during Spring Sport Fish Surveys on Chickamauga Reservoir, 1995-2006. Largest EF Catch Rate Mean Weight Bass >4 Bass >5 bass Year (no./hr.) (Ibs.)  % Harvestable lbs. lbs. (lbs.) 2006 39.4 1.3 71.7 14 7 7.1 2005 72.6 1.3 36.9 ,15 9 6.2 2004 40.9 1.3 60.2 13 6 6.6 2003 62.0 1.3 65.8 23 8 6.4 2002 57.4 1.1 59.4 9 4 6.6 2001 34.5 0.8 45.2 0 0 2.8 2000 34.4 1 51.2 3 0 4.8 199q 10.6 1.3 60.7 3 1 6.1 1998 37.2 1.1 44.5 9 2 6.6 1997 40.2 1 70.1 8 4 8.7 1996 51 1.2 42.6 13 9 7.9 1995 62 1.2 61.8 28 12 8.3 Averaae 45.2 1.2 55.8 11.5 5.2 6.5 22

Table 14. Black Bass Catch Per Hour Compared to Habitat Types by Location during Spring S Sport Fish Surveys on Chickamauga Reservoir, 2006. Habitat Designation Reservoir and Site Good Fair Poor Chickamauga Harrison Bay 58(4) 36(4) .41(4) Sale Creek 27(4) 45(4) 15(4) Skull Island 79(2) 42(8) 17(2) Catch per hour = number of fish collected per hour ( ) = number of transects sampled at each location Quantity Parameter Qulity Parameters Angler Succ Angling PressureS I I [ Figure 1. Parameters used to calculate the Sport Fishing Index (SFI). 0 23

S S 60 Excellent 50 40 i:..::.::.::.:.

                                .TRM490.5-Tiransitoi"                               ::          Fai ============I                                   ==             .         S: ores: : ::::::::::::::

0

                      *T -R-TRM

. R .IM - -4

:7 i ., . :- : :o: :e: : :a:

482-ForebayExeln516  : : ::: : :::::: :: ::::: :::::::::::::::::::: :::: : :: :: :::::::: G o o d 4 1..0 30 LL TRIM::529 Inlo  :*-*:::::::::::::: ...Poor .. :.......... ........ ..........  :. .,Fair . 32-40::::::::::::!:.i:::ii:/:

.i :3*.:F:.:*~ e: .::.:

                                                                  ~ i [::::**:::?::::*:i::::i:i M:i 7*                                                                                   ~ bo r 24 2:*-3 1l~

0 :G -~i.::i:*::**:i:.i*i: iPo i :::::i:;i:: 20 10 0 1993 1994 1995 1996. 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 Year Figure 2. Annual Chickamauga Reservoir RFAI scores for sample years between 1993 and 2006. 24

60 - --------- 50 40 0Black bass.

                             ,_*~~                                                                ~~~~~ ~~

i:Spo tted b:.6assii ::i*!iii: 0

    ) 30                                                                                         *.Sauger U.                                                                                              MStriped bass 5 Bluegill 20U    Channel catfish::

MWhite bass 10 1997 1998 :1999 2000 2001 2002 2003 2004 2005 Year Figure 3. Sport Fishing Index results for Chickamauga Reservoir between 1997 and 2005. 25

LENGTH FREQUENCY

                                                  .ALL     SITES CHICKAMAUGA 2006 z

[ 4164

                                                                      .'; '" ;"".'; '.'I , *"' , *"'. ,   i'."   ;" .'17". ,

3 5 7 9 11 13 15 17 19 21 23 25 INCH GROUP Figure 4. Length frequency distribution for largemouth bass collected from Chickamauga Reservoir (all sites) during the Spring Sport Fish Survey, 2006. 0 RSD VALUIES (Quality) MAINSTEM RESERVOIRS SPRING 2006 50 45 40 25, S20 15 Desirable RSD 15 Range 10= 414 0 5

                        =9                             3                                                W:*:::*::*.*. ::C.

Q1

                      ,=:L 0

Reservoir Figure 5. Relative stock density values for Tennessee River reservoirs calculated from 2006 Spring Sport Fish Survey samples. 0 26

PSD VALUES MAINSTEM RESERVOIRS SPRING 2006: 90 80 70 ** 1. .  ::-**:P*i

                                  .   ..      s   r i~~ : ::*: ::....:            ,\. . . . . . .. :.: .:.                       *.....   ... .. :     ...

60 Ci50 Desi'"ble PS. Range:.H.::: . U S40 -- 30 4-31 20 10

                  .0 Z

2*"3 .5i: 0 0 ......... R es ervoir Figure 6. Proportional stock density values for Tennessee River reservoirs calculated from 2006 Spring Sport Fish Survey samples. 0 CHICKAMAUGA Wr ALL S.ITES 2006 I=Percent -- # of Fish]

1:20: 250 100 0~i~iiiiiii~i~!ii:iiiiliiiiiiiiiiiiii 200

                              .80 150 C

6) 60 U

0100 6) a- 40 E 20 50 z 0 I 0-7 8-11 12.14 15-19 20.24 25+ Relative Stock Size by Inch Group Figure 7. Chickamauga Reservoir mean relative weights (Wr) for largemouth bass by RSD category and number of fish during 2006. 0 27

Biological Monitoring of the Tennessee River Near Sequoyah Nuclear Plant Discharge 2007 by Dennis S. Baxter Jeffrey W. Simmons May 2008 Tennessee Valley Authority Aquatic Monitoring and Management Knoxville, Tennessee

Table of Contents Lis t o f T a b le s ................................................................................................................................ i L ist o f F ig u re s ........................... ................................................................... ............................... ii A c ro n y m s ........................................................................................................... ....................... iii In tro d u ctio n .................................................................................................................................. I Me th o d s ....................................................................................................................................... 2 Fish C o m m u n ity ....................................................................................................................... 2 Benthic Macroinvertebrate Community ............................................................................ 3 S pring Sport Fish S urvey ........................................................................... ........................ 4 R esu lts and Discussio n ........................................................................ 4........................... F is h C o m m u n ity ....................................................................................................................... 4 Benthic Macroinvertebrate Community .................................... 5 Spring Sport Fish Survey .............................................. 5 Chickamauga Reservoir Flow ........................................... 6 L ite ratu re C ited ........................................................................................................................... 7 List of Tables Table 1. Scoring Results for the Twelve Metrics and Overall Scores for all RFAI Sites Sampled in Chickamauga Reservoir, 2007 .......................... 8 Table 2. RFAI Scores Developed Using the RFAI Metrics from Samples Collected During 1993 to 2007, Upstream and Downstream of Sequoyah Nuclear Plant ......... I........................................................................... ............... 9 Table 3. Scoring Criteria for Forebay, Transition, and Inflow Sections of Upper Mainstem Reservoirs in the Tennessee River System. Upper Mainstem Reservoirs include Chickamauga, Fort Loudoun, Melton Hill, Nickajack, Tellico, and Watts Bar ............................................................. 10 Table 4. Species Listing and Catch Per Unit Effort for Forebay Transects on Chickamauga Reservoir During Fall Electrofishing and Gill Netting, 2007. (Electrofishing Effort = 300 Meters of Shoreline, Gill Netting Effort = 10 Net-N ig h ts) ................................................................................................................... 11 Table 5. Species Listing and Catch Per Unit Effort for the Transition and Inflow Transects on Chickamauga Reservoir During Fall Electrofishing and Gill Netting, 2007. (Electrofishing Effort = 300 Meters of Shoreline, Gill Netting Effort = 10 Net-Nights) ................... ..................... 12 Table 6. Individual Metric Ratings and the Overall RBI Field Scores for Upstream (TRM 490.5) and Downstream (TRM 482) Sampling Sites Near Sequoyah Nuclear Plant, Chickamauga Reservoir, 2007 ............................................................... 14 0 i

List. of Tables (continued) Table 7. Average Mean Density Per Square Meter of Benthic Taxa Collected at Upstream (TRM 490.5) and Downstream (TRM 482) Sampling Sites Near Sequoyah Nuclear Plant, Chickamauga Reservoir, 2007 ............................... 15 Table 8. RBI Field Scores from Data Collected During 1994-2007 at Chickamauga Reservoir Transition (TRM 490.5) and Forebay (TRM 482.0 and TRM 472.3) S ites .................. .............................................................................................. . ..... 17 Table 9. Electrofishing Catch Rates and Population Characteristics of Black Bass Collected During Spring Sport Fish Surveys on Chickamauga Reservoir, 1995-2007 .......................... ....................... 17 Table 10. Black Bass Catch Per Hour Compared to HabitatTypes by Location During Spring Sport Fish Surveys on Chickamauga Reservoir, 2007 ...................... 18 List of Figures .Figure 1. Annual Chickamauga Reservoir RFAI scores for sample years between 1993 and 2007. .................................................................................................... 19 Figure 2. Length frequency distribution for largemouth bass collected from Chickamauga Reservoir (all sites) during the Spring Sport Fish Survey, 2 00 7 ................................................................ .......................................................... 20 Figure 3. Relative stock density values for Tennessee River reservoirs calculated from 2007 Spring Sport Fish Survey samples ........................................................... 20 Figure 4. Proportional stock density values for Tennessee River reservoirs calculated from 2007 Spring Sport Fish Survey samples ..................... .......................... 21 Figure 5. Chickamauga Reservoir mean relative weights (Wr) for largemouth bass by RSD category and number of fish during 2007 ............................................... 21 Figure 6. Weekly average flows in cubic feet per second from Watts Bar Dam during October 2006 through September 2007 with long term trend line from 1976 th ro ugh 2006 ............................................................................................................. 22 i1

Acronyms BIP Balanced Indigenous Population NPDES National Pollutant Discharge Elimination System PSD Proportional Stock Density QA Quality Assurance RBI Reservoir Benthic Macroinvertebrate Index RFAI Reservoir Fish Assemblage Index RSD Relative Stock Density RSDM Relative Stock Density of Memorable-sized RSDP Relative Stock Density of Preferred-sized RSDT Relative Stock Density of Trophy-sized SAHI Shoreline Assessment Habitat Index SQN Sequoyah Nuclear Plant SSS Spring Sport Fish Survey-TRM Tennessee River Mile TVA Tennessee Valley Authority VS Vital Signs Wr Relative Weight i1i

Introduction Section 316(a) of the Clean Water Act specifies that industrial, municipal, and other facilities must obtain permits if their thermal discharges go directly to surface waters. Industries responsible for point-source discharges of heated water can obtain a variance from state water quality standards if the industry can demonstrate compliance with thermal criteria by documenting the maintenance of Balanced Indigenous Populations (BIP) of aquatic life in the vicinity of its discharge. Sequoyah Nuclear Plant's (SQN) current National Pollutant Discharge Elimination System (NPDES) permit number TN0026450 states, "For Section 316(a), the permittee shall analyze previous and new data to determine whether significant changes have occurred in the plant operation, reservoir operation, or in stream biology that would necessitate the need for changes in the thermal variance." The permittee shall use the Reservoir Fish Assemblage Index (RFAI) to assess Chickamauga Reservoir fish community health. Any apparent decline in the fish community health will be further investigated to discover whether it is a valid conclusion and if it is real to identify possible sources for the fish community decline. As part of the identification of potential sources for the decline, the instream effects of the discharges made under this permit. will be investigated (TDEC 2000). In response to this requirement, Tennessee Valley Authority's (TVA's) Vital Signs (VS) monitoring program (Dycus and Meinert 1993) will be used to evaluate areas of Chickamauga Reservoir upstream and downstream of SQN discharge. The purpose of this document is to briefly summarize and provide results of the Calendar Year 2007 monitoring and analyses to the Tennessee Department of Environment and Conservation and compare these results with historical monitoring data. Prior to 1990,, TVA conducted reservoir ecological assessments to meet specific needs as they arose. In 1990, TVA instituted a Valley-wideVS monitoring program which is a broad-based evaluation of the overall ecological conditions in major reservoirs. Data are evaluated with a multi-metric monitoring approach utilizing five environmental indicators: dissolved oxygen, chlorophyll, sediment quality, the benthic macroinvertebrate community, and the fish community. When this program was initiated, specific evaluation techniques were developed for -each indicator, and these techniques were fine-tuned in order to better represent ecological conditions. The outcome of this effort was the development of a multi-metric evaluation to assess the fish assemblage and benthic community. The two indices, the RFAI and the Reservoir Benthic Macroinvertebrate Index (RBI), have proven successful in TVA's monitoring efforts as well as for other federal and state monitoring programs. Therefore, they will form the basis of evaluating these monitoring results. For consistency, only RFAI analyses between 1993 and 2007 will be utilized. The RBI is used primarily to support the RFAI analysis. The TVA Spring Sport Fish Survey (SSS) is conducted to evaluate sport fish populations in TVA Reservoirs. The results of the survey are used by state agencies to protect, improve, and assess the quality of sport fisheries. Predominant habitat types in the reservoir are surveyed to determine sport fish abundance. In addition to accommodating TVA and state databases, this surveying method aligns with TVA Watershed Team and TVA's Reservoir Operations Study objectives. Sample sites are selected using the shoreline habitat characteristics employed by the Watershed Teams. The survey targets three species of black bass (largemouth, smallmouth, and spotted bass) and black and white crappie. These species are the predominant sport fish sought after by fisherman. I

Methods Fish Community Reservoirs are typically divided into three zones for VS monitoring - inflow, transition, and forebay. The inflow zone is generally in the upper reaches of the reservoir and is riverine in nature; the transition zone or mid-reservoir is the area where water velocity decreases due to increased cross-sectional area; and the forebay is the lacustrine area near the dam. The Chickamauga-Reservoir inflow zone sample site is located at Tennessee River Mile (TRM) 529.0, the transition zone sampling site is located at TRM 490.5, and the forebay zone sampling sites are located at TRM 482.0 and 472.3. The transition zone sampling site, which is located approximately 7.2 river miles upstream of the SQN discharge, is used as a control site to provide upstream data for 316(a) thermal variance studies conducted during sample years from 1993 to 2007. The downstream station is located at TRM 482.0 and has been sampled each year from 1999 to 2007 to monitor Chickamauga Reservoir aquatic communities in close proximity to the SQN thermal effluent. Previously, the downstream station was located at TRM 472.3 during sample years from 1993 to 1997. Sampling effort consisted of fifteen 300-meter electrofishing runs (approximately 10 minute duration) and ten experimental gill net sets (five 6.1 meter panels with mesh sizes of 2.5, 5.1, 7.6, 10.2, and 12.7 cm) per site. Attained values for each of the 12 metrics were compared to reference conditions for transition zones of lower mainstream Tennessee River reservoirs and assigned scores based upon three categories hypothesized to represent relative degrees of degradation: least degraded - 5; intermediate - 3; and most degraded - 1. These categories are . based on "expected" fish community characteristics in the absence of human-induced impacts other than impoundment. Individual metric scores for a site are summed to obtain the RFAI score. Comparison of the attained RFAI score from the potential impact zone to a predetermined criterion has been suggested as a method useful in identifying presence of normal community, structure and function and hence existence of a BIP. For multi-metric indices, two criteria have been suggested to ensure a conservative screening for a BIP. First, if an RFAI score reaches 70% of the highest attainable score (adjusted upward to include sample variability), and second, if fewer than half of RFAI metrics potentially influenced by thermal discharge receive a low (1) or moderate (3) score, then normal community structure and function would be present indicating that a BIP existed. Under these conditions, the heated discharge would meet screening criteria and no further evaluation would be needed. Potential, RFAI scores range from 12 to 60. Ecological health ratings (12-21 ["Very Poor"], 22-31 ["Poor"], 32-40 ["Fair"], 41-50 ["Good"], or 51-60 ["Excellent"]) are then applied to scores. As discussed in detail below, the average variance for RFAI scores in TVA reservoirs is 6 (+ 3). Therefore, any location that attains an RFAI score of 45 (42 + our sample variance of 3) or higher would be considered to demonstrate a BIP. It must be stressed that scores below this endpoint do not necessarily reflect an adversely impacted fish community. The endpoint is used to serve as a conservative screening level; for example, any fish community that meets these criteria is obviously not adversely impacted. RFAI scores below this level would require a more in-depth look to determine if a BIP exists. If a score below this criterion is obtained, an inspection of individual RFAI metric results would be an initial step to help identify if SQN operation is a contributing factor. This approach is appropriate if a validated multi-metric index is being used and scoring criteria applicable to the zone of study are available. Additionally, Supstream/downstream site comparisons can be used to identify if SQN operation is adversely 2

affecting the downstream fish community. A similar or higher RFAI score at the downstream station compared to the upstream (control) station is used as one basis for determining presence/absence of SQN operational impacts on the resident fish community. Definition of similar" is integral to accepting the validity of these interpretations. The Quality Assurance (QA) component of VS monitoring deals with how well the RFAI scores can be repeated and is accomplished by collecting a second set of samples at 15%-20% of the stations each year. Experience to date with the QA component of VS shows that the comparison of RFAI index scores from 54 paired sample sets collected over a seven year period ranged from 0 to 18 points, the 7 5 th percentile was 6, the 9 0 th percentile was 12. The mean difference between these 54 paired scores is 4.6 points with 95% confidence limits of 3.4 and 5.8. Based on these results, a difference of 6 points or less is the value selected for defining "similar" scores between upstream and downstream fish communities. That is, if the downstream RFAI score is within 6 points of the upstream score, the communities will be considered similar. It is important to bear in mind that differences greater than 6 points can be expected simply due to method variation (25% of the QA paired sample sets exceeded that value). When this occurs, a metric-by-metric examination will be conducted to determine what caused the difference in scores and the potential for the difference to be thermally related. Benthic. Macroinvertebrate Community Ten benthic grab samples were collected at equally spaced points along a transect extending from the right descending bank to the left descending bank at each site. . A Ponar sampler was used for most samples but a Peterson sampler was used when larger substrate was encountered. Collection and processing techniques followed standard VS procedures. Bottom

• sediments were washed on a 533p.screen; organisms were then picked from the screen and remaining substrate and identified to Order or Family level in the field using no magnification.

Benthic community results were evaluated using seven community characteristics or metrics. Results for each metric were assigned a rating of 1, 3, or 5 depending upon how they compared to reference conditions developed for VS sample sites. The ratings for the seven metrics were summed to produce a total benthic score for each sample site. Each reservoir section (inflow, transition, or forebay) differs in their maximum potential for benthic diversity; thus, the criteria for assigning metric ratings were adjusted accordingly such that the total benthic scores from sites at different reservoir sections are comparable. Potential. scores ranged from 7 to 35. Ecological health ratings (7-12 ["Very Poor"], 13-18 ["Poor"], 19-23 ["Fair"], 24-29 ["Good"], or 30-35 ["Excellent"]) are then applied to scores. A similar or higher benthic index score at the downstream site compared to the upstream site is used as basis for determining absence of impact on the Chickamauga Reservoir benthic macroinvertebrate community related to SQN's thermal discharge. The QA component of VS monitoring shows that the comparison of benthic index scores from 49 paired sample sets collected over a seven year period ranged from 0 to 14 points; the 7 5th percentile was 4 and the 9 0 th percentile was 6. The mean difference between these 49 paired scores is 3.1 points with 95 percent confidence limits of 2.2 and 4.1. Based on these results, a difference of 4 points or less is the value selected for defining "similar" scores between upstream and downstream benthic communities. That is, if the downstream benthic score is within 4 points of the Upstream score, the communities will be considered similar and it will be concluded that SQN has had no effect. Once again, it is important to bear in mind that differences greater than 4 points can be expected simply due to method variation (25% of the 3

QA paired sample sets exceeded that value). When this occurs, a metric-by-metric examination will be conducted to determine what caused the difference in scores and the potential for the difference to be thermally related. Spring Sport Fish Survey A Spring Sport Fish Survey was conducted on Chickamauga Reservoir March 20-22, 2007. During the sampling period, water levels on Chickamauga Reservoir were 676.7 to 677.2 msl (summer pool level is 682.5 msl). Sampling was conducted using a boat mounted electrofishing unit at a total of twelve sites at Harrison Bay, Ware Branch, and Sale Creek. Sampling effort at each site consisted of thirty minutes of continuous electrofishing in the littoral zones of prominent habitat types present. After being stunned, fish were collected with dip nets, counted, weighed, measured, and then released unharmed. Results of the SSS monitoring were calculated using Shoreline Assessment Habitat Index (SAHI), Relative Stock Density (RSD), Proportional Stock Density (PSD), and Relative Weight (Wr). Habitat type is evaluated using the SAHI metric and is a critical component incorporated into the SSS. The resultant habitat designations ("Good", "Fair", and "Poor") are correlated to black bass abundance (numbers/hour). RSD is the number of fish greater than a minimum preferred length in a stock divided by the number of fish greater than or equal to a minimum stock size. PSD is the number of fish greater than or equal to a minimum quality length in a sample divided by the number of fish greater than or equal to a minimum stock length. Wr is an index that quantifies fish condition and the preferred range value is 90%-105% for moderate density bass populations such as those found in the Tennessee Valley latitudes. Results and Discussion Fish Community. RFAI fish data collected during autumn 2007 from TRM 490.5 upstream from SQN resulted in a RFAI score of 44 ("Good"), while the downstream site at TRM 482 scored 38 ("Fair") (Table 1). Although the downstream site scored "Fair", this site has averaged "Good'"over all sample years with a average score of 42 (70% of the maximum score) (Table 2).. Even though the downstream site scored six points and is considered similar, individual RFAI metrics were examined.to evaluate this difference and to determine if this score was indicative of thermal effects (Table 3). Species richness and, composition metrics constituted four points of the six-point score difference (Table 1). The total number of species at the upstream site was 31, compared to 26 at-the downstream site, which resulted in a two point scoring difference for the metric "Number of species". During 2007, seven species were collected at the upstream site that were not found at the downstream site (smallmouth buffalo, white bass, warmouth, white crappie, logperch, brook silverside, and chestnut lamprey) and one species was collected at the downstream site that was not encountered at the upstream site (golden redhorse) (Tables 4 and 5). Although more species were collected at the upstream site, all seven species mentioned above were collected in low numbers. The downstream site (TRM 482) scored one point lower than the upstream site (TRM 490.5) for each of the metrics "Percent tolerant individuals", "Percent top carnivores", and "Average number per run" because of a lower catch rate in gill net samples at the downstream site (Table ._ 1). 4

It is important to note that the upstream site is scored with transition criteria and the S downstream site is scored using forebay criteria (Table 3). More accurate comparisons can be made between sites that are located in the same reservoir zone (i.e., transition to transition). Due to the location of SQN, it is not possible to have an upstream and downstream site within the same reservoir zone. SQN is located at the downstream end of the transition zone on Chickamauga Reservoir; therefore the downstream site is located in the upstream section of the forebay. The physical and chemical composition of a forebay is different than that of a transition; consequently, inherent differences exist among the aquatic communities (e.g. species diversity is often higher in a transition than a forebay zone). RFAI scores (Table 1, Figure 2) and electrofishing and gill netting catch rates (Tables 4 and 5) are presented for Chickamauga Reservoir inflow and forebay sites (TRM 529 and 472.3) to provide an overview of ecological health throughout the reservoir; however, aquatic communities at these sites are not affected by SQN temperature effects and are not used to determine BIP in relation to SQN. Both of these sites scored "Good" during 2007. Benthic Macroinvertebrate Community Benthic macroinvertebrate data collected during autumn 2007 from TRM 490.5 upstream from SQN resulted in a RBI score of 21 ("Fair"), while the downstream site at TRM 482 scored 25 ("Good") (Table 6). Table 7 provides density by taxon from the 2007 samples at these sites. With the exception of the 2000 and 2007 sample, the RBI scores have remained in the "Good" to "Excellent" ecological health range for all sampling seasons at both sites (Table 8). These data indicate that. a healthy benthic macroinvertebrate community exists in both the upstream

• .and downstream vicinity of SQN and that the plant is not adversely impacting this fauna.

Data collected in Chickamauga Reservoir forebay (TRM 472.3) resulted in a RBI score of 19 "Fair". This site is located 11 river miles downstream of SQN and sampling results should not

• reflect temperature effects from the plant. This site is included to provide additional data on the downstream health of the benthic macroinvertebrate community (Table 8).

Spring Sport Fish Survey A total of 18 hours of electrofishing resulted in collection of 940 largemouth bass, 123 spotted bass, and 38 smallmouth bass; of these, 63.2% were harvestable size (>10 inches). Overall catch rate (61.1 fish/hour) was substantially more than the 2006 survey (39.4 fish/hour), but was similar tothe average catch rate from all thirteen sample years (Table 9). The largest black bass collected was a 6.7 pound largemouth bass taken from Harrison Bay. Large bass were well represented with 50 bass greater than three pounds, 20 greater than four pounds, and 8 over five pounds. The three andfour-pound categories showed an increase of 78% and 70% over 2006 results, while the five-pound category remained constant. Length frequency histograms illustrated a bimodal distribution of black bass with the dominant size classes being the 6-7 inch and 11-13 inch groups (Figure 3). Fish >14 inches comprised 18% of the overall sample. All size classes up to 21 inches were represented in the population and one was in the 27 inch class. Habitat type is derived from the SAHI which was developed by TVA's Resource Stewardship Program. The resultant habitat designations ("Good", "Fair", and "Poor") are correlated to black bass abundance (numbers/hour). Among the three areas sampled during 2007, the 5

correlations of habitat type to black bass abundance at Harrison Bay were positive while bass

• collected at Sale Creek and Skull.Island showed some variability among habitat types, i.e., the catch rates (abundance) did not align with the habitat designation types (Table 10).

The following results describe the quality andcondition of black bass collected in Chickamauga Reservoir during spring 2007: The RSD value (21) fell within the desirable range (10-25) (Figure 4). The PSD value (65) was also within the preferred range (40-70) (Figure 5). Wr values shown in Figure 6 are designated by inch groups which reflect the classical categories, i.e., 0-7 = substock, 8-11 = stock, 12-14 = quality, 15-19 = preferred, 20-24 memorable and 25+ = trophy. All categories except the trophy group fell within the desired range, which reflects excellent condition of black bass in all size groups of the population. In addition, field observations of large numbers of prey fish indicate an abundance of forage for all size classes of black bass. Only 149 crappie (11 black and 138 white crappie) were collected during the survey. Crappies were collected predominantly from tree tops, stumps, and other physical structures in shallow water. Optimum water temperatures for crappie spawning occurred earlier in the spring of 2007. Chickamauga Reservoir Flow Average weekly flows from Watts Bar Dam from October 2006 to September 2007 are shown in Figure 6. Weekly average flows were 83% less than the 30-year long-term weekly average

 -flows from 1976 through 2006. The Tennessee Valley has experienced an exceptional drought and it was the worst on record in the last 118 years. Even with the low flow conditions resulting from the drought, annual aquatic monitoring has not reflected, negative trends in the aquatic communities in Chickamauga Reservoir. Spawning success of fish or year-class strength would be apparent in subsequent years to come.

6

Literature Cited Dycus, D. L. and D. L. Meinert. 1993. Reservoir Monitoring, Monitoring and Evaluation of Aquatic Resource Health and Use Suitability in Tennessee Valley Authority Reservoirs: Tennessee Valley Authority, Water Resources, Chattanooga, Tennessee, TVA/WM-93/15. Tennessee Department of Environment and Conservation. 2000. Draft NPDES Permit Number TN0026450. 7

0 0 Table 1. Scoring Results for the Twelve Metrics and Overall Scores for all RFAI Sites Sampled in Chickamauga Reservoir, 2007. Forebay Inflow TRM 482.0 TRM 529.0 Downstream Site Metric Obs Score Obs Score A. Species richness and composition

1. Number of species 26 3 27 3

2. Number of centrarchid species 6 5 7 5

3. Number of benthic invertivores 3 1 6 3

4. Number of intolerant species 6 4 3 5

5. Percent tolerant individuals electrofishing 75.7 0.5 75.6 1 gill netting. 37.7 0.5

6. Percent dominance by one species electrofishing 36.3 1.5 51.9 1 gill netting 31.6 0.5

7. Number norn-native species .electrofishing 0.7 2.5 0.3 5 gill netting , 0.4 2.5

8. Number of top carnivore species 9 5 8 5 B. Trophic composition

9. Percent top carnivores electrofishing 6.4 1.5 12 3 gill, netting 40.4 1.5

10. Percent omnivores electrofishing 22 2.5 16.1 5 gill netting 51.3 0.5

8

0Table 1. (continued) Forebay .Inflow TRM 482.0 TRM 529.0 Downstream Site Metric Obs Score Obs Score C. Fish abundance and health

11. Average number per run electrofishing 37.3 0.5 51.6 3 gill netting 22.8 1.5

12. Percent anomalies electrofishing 1.4 2.5 3.2 3 gill netting 0.4 1.3 2.5 . ,i$ 2.6 - -

RFAI 38 444 Fair d..d Good

 *TRM 472.3 and 482 scored with forebay criteria, TRM 49C).5 scored with transition criteria, and TRM 529 scored with inflow criteria (Refer to Table 3). RFAI Scores: 12-21 ("Very Poor"), 22-31 ("Poor"), 32-40 ("Fair"), 41-50 ("Good"), or 51-60 ("Excellent")

Table 2. RFAI Scores Developed Using the RFAI Metrics from Samples Collected During 1993 to 2007, Upstream and Downstream of Sequoyah Nuclear Plant. Station Reservoir Location 1993 1994 1995 1997 1999 2000* 2001 2002* 2003 2004* 2005 2006 2007 1993-2007

• Average Upstream* Uptrea Chckamuga Chickamauga 490.5 TRM 49 40 46 39 45 46 45 51 42 49 48 47 44 45 TRM Downstream Chickamauga 482.0 41 48 46 43 45 41 39 37 38 42 Downtrea Downstream Chckamuga Chickamauga 472.3

47. 44 44 47 39- 45 45 48 46 43 43 46 44 41 `44

*The 2000, 2002, 2004, and 2006 sample years were not part of the VS monitoring program, however the same methodology was applied.

9

Table 3. Scoring Criteria for Forebay, Transition, and Inflow Sections of Upper Mainstem Reservoirs in the Tennessee River System. Upper Mainstem Reservoirs include Chickamauga, Fort Loudoun, Melton Hill, Nickajack, Tell ico, and Watts Bar. Scoring Criteria Forebay Transition Inflow Metric Gear 1 3 5 1 3 5 1 3 5 A. Species richness and composition

1. Total species Combined <14 14-27 >27 <15. 15-29 >29 <14 14-27 >27

2. Total Centrarchid species Combined <2 2-4 >4 <2 2-4 >4 <3 3-4 >4

3. Total benthic invertivores Combined <4 4-7 >7 <4 4-7 >7 <3 3-6 >6

4. Total intolerant species Combined <2 2-4 >4 <2 2-4 >4 <2 2-4 >4

5. Percent tolerant individuals Electrofishing >62% 31-62% <31% >62% 31-62% <31% >58% 29-58% <29%

Gill netting >28% 14-28% <14% >32% 16-32% <16%

6. Percent dominance by 1 species Electrofishing >50% 25-50% <25% >40% 20-40% <20% >46% 23-46% <23%

Gill netting >29% 15-29% <15% >28% 14-28% <14%

7. Percent non-native species Electrofishing >4% 2-4% <2% >6% 3-6% <3% >17% 8-17% <8%

Gill netting >16% 8-16% <8% >9% 5-9% <5%

8. Total top carnivore species Combined <4 4-7 >7 <4 4-7 >7 <3 3-6 >6 B. Trophic composition

9. Percent top carnivores Electrofishing <5% 5-10% >10% <6% 6-11% >11% <11% 11-22% >22%

Gill netting <25% 25-50% >50% <26% 26-52% >52%

10. Percent omnivores Electrofishing >49% 24-49% <24% >44% 22-44% <22% >55% 27-55% <27%

Gill netting >34% 17-34% <17% >46% 23-46% <23% C. Fish abundance and health 11.. Average number per run Electrofishing 5121 121-241 >241 <105 105-210 >210 <51 51-102 >102 Gill netting <12 12-24 >24 <12 12-24 >24

12. Percent anomalies Electrofishing >5% 2-5% <2% >5% 2-5% <2% >5% 2'5% <2%

Gill netting >5% 2-5% <2% >5% 2-5% <2% 10

Table 4. Species Listing and Catch Per Unit Effort for Forebay Transects on Chickamauga Reservoir During Fall Electrofishing and Gill Netting, 2007. (Electrofishing Effort 300 Meters of Shoreline, Gill Netting Effort = 10 Net-Nights) Forebay TRM 472.3 Forebay TRM 482.0 Electrofishing Electrofishing Gill Netting Electrofishing Electrofishing Gill Netting Catch Rate Catch Rate Catch Rate Catch Rate Catch Rate Catch Rate Common Name Per Per Per Per Per Per Run Hour Net Night Run Hour Net Night Spotted gar 0.07 0.30 0.10. 0.27 1.27 0.10 Longnose gar 0.10 Skipjack herring 2.40 1.80 Gizzard shad 4.60 20.54 5.90 7.27 34.49 ,7.20 Threadfin shad 0.13 0.60 0.13 0.63 0.10 Hybrid shad 0.30 Common carp 0.10 0.10 Golden shiner 0.13 0.60. 0.10 Emerald shiner 2.67 12.66 Spotfin shiner 0.27 1.19 1.33 6.33 Bluntnose minnow 0.07 0.32 Bullhead minnow 0.20 0.95 Spotted sucker 0.53 2.53 Golden redhorse 0.07 0.32 a catfish 1.10 0.07 0.32 3.20 (annel catfish 0.20 0.89 0.60 0.80 3.80 0.80 Flathead catfish 0.47 2.08 0.30 0.07 0.32 0.40 Yellow bass 7.30 3.20 Warmouth 0.20 0.89 Redbreast sunfish 7.67 34.23 4.53 21.52 0.10 Green sunfish 0.47 2.08 0.20, 0.95 Bluegill 25.07 111.*90 0.70 13.53 64.24 0.80 Longear sunfish 0.40 1.79 0.60 2.85 Redear sunfish 1.47 6.55 0.30 2.67 12.66 0.30 Smallmouth bass 0.20 0.89 0.10 0.07 0.32 0.10 Spotted bass 0.87 3.87 1.90 0.60 2.85 1.20 Largemouth bass 1.07 4.76 0.90 1.33 6.33 0.20 Black crappie 0.07 0.30 5.70 0.07 0.32 2.10 Yellow perch 0.40 1.79 0.60 0.13 0.63 Freshwater drum 0.60 Brook silverside 0.13 0.60 Inland silverside 1.47 6.55 0. 13 0.63 Total 54.95 240.93 32.10 37.34 177.24 22.80 Number Samples 15 10 15 10 Number Collected 680 280 560 228 Species Collected 20 15 23 20 11

Table 5. Species Listing and Catch Per Unit Effort for the Transition and Inflow Transects on Chickamauga Reservoir During Fall Electrofishing and Gill Netting, 2007. (Electrofishing Effort = 300 Meters of Shoreline, Gill Netting Effort = 10 Net-Nights) Transition TRM 490.5. Inflow TRM 529.0 Electrofishing Electrofishing Gill Netting Electrofishing Electrofishing Catch Rate Catch Rate Catch Rate Catch Rate Catch Rate Common Name Per Per Per Per Per Run Hour Net Night Run Hour Longnose gar - 0.10 0.07 0.32 Spotted gar 1.67 7.31 0.10 Skipjack herring - 3.20 - Gizzard shad 16.33 71.64 7.70 7.40 35.02 Threadfin shad 0.07 0.29 - 0.07 0.32 Common carp 0.27 1.17 - 0.07 0.32 Golden shiner 1.67 7.31 0.20 0.07 0.32 Emerald shiner 2.40 10.53 0.40 1.89 Spotfin shiner 0.60 2.63 1.80 8.52 Steelcolor shiner - - 0.07 0.32 Bluntnose minnow 0.20 0.88 - - Bullhead minnow 0.07 0.29 Smallmouth buffalo 0.07 0.29 0.10 Northern hog sucker - - - 0.07 0.32 Spotted sucker 0.13 0.58 0.30 0.33 1.58 Black redhorse - - - 0.13 0.63 Golden redhorse - 0.60 2.84 Blue catfish - - 1.10 - - Channel catfish 0.20 0.89 0.60 0.80 3.79 Flathead catfish 0.47 2.08 0.30 1.87 8.83 Yellow bass - - 7.30 0.47 2.21 Striped bass--- 0.07 0.32 Rock bass - - 0.07 0.32 Warmouth 0.20 0.89 0.40 1.89 Redbreast sunfish 7.67 34.23 1.47 6.94 Green sunfish 0.47 2.08 _ 0.20 0.95 Bluegill 25.07 111.90 0.70 26.80 126.81 Longear sunfish 0.40 1.79 - 0.60 2.84 Redear sunfish 1.47 6.55 0.30 3.60 17.03 Smallmouth bass 0.20 0.89 0.10 0.27 1.26 Spotted bass 0.87 3.87 1.90 2.00 9.46 Largemouth bass 1.07 4.76 0.90 1.13 5.36 Black cranoie 0.07 0.30 5.70 0.27 1.26 12

Table 5. (continued) Transition TRM 490.5 Inflow TRM 529.0 Electrofishing Electrofishing Gill Netting Electrofishing Electrofishing Catch Rate Catch Rate Catch Rate Catch Rate Catch Rate Common Name Per Per Per Per Per Run Hour Net Night Run Hour Yellow perch 0.40 1.79 0.60 Logperch - 0.33 1.58 Freshwater drum - - 0.20 0.95 Brook silverside 0.13 0.60 - - Inland silverside 1.47 6.55 - Total 54.95 240.93 32.10 51.63 244.20 Number Samples 15 10 15 Number Collected 680 280 774 Species Collected 20 15 29 13

Table 6. Individual Metric Ratings and the Overall RBI Field Scores for Upstream (TRM 490.5) and Downstream (TRM 482) Sampling Sites Near Sequoyah Nuclear Plant, Chickamauga Reservoir, 2007. TRM 490.5 TRM 482 Upstream Downstream Metric Obs Rating Obs Rating

1. Average number of taxa 4.7 5 4.1 3

2. Proportion of samples with long-lived organisms 0.5 3 0.6 3

3. Average number of EPT taxa 0.3 1 0.5 3

4. Average proportion of oligochaete individuals 5.2 5 6.3 5

5. Average proportion of total abundance comprised by 93.4 1 90.6 3 the two most abundant taxa

6. Average density excluding chironomids and 56.7 1 125 3 oligochaetes

7. Zero-samples - proportion of samples containing no 0 5 0 5

. organisms Benthic Index Score 21 25 Fair Good

 *TRM 490.5 scored with transition criteria, TRM 482 scored with forebay, criteria.

RBI Scores: 7-12 ("Very Poor"), 13-1.8 ("Poor"), 19-23 ("Fair"), 24-29 ("Good"), or 30-35 ("Excellent") 14

Table 7. Average Mean Density Per Square Meter of Benthic Taxa Collected at Upstream (TRM 490.5) and Downstream (TRM 482) Sampling Sites Near Sequoyah Nuclear Plant, Chickamauga Reservoir, 2007. Chickamauga Reservoir TRM 490.5 TRM 482 Upstream Downstream Species Mean Density Mean Density Tubellaria Tricladida Planariidae 0 0 Oligocheata Oligochaetes 28 13 Hirudinea 10 3 Crustacea Amphipoda 0 0 Isopoda 0 0 Insecta Ephemeroptera Mayflies Ephemeridae Hexagenia (<10 mm) 0 12 Hexagenia (>10 mm) .10 18 Megaloptera Sialidae Sialis sp. 0 0 Odonata. 0 0 Anisoptera Zygoptera Trichoptera Caddisflies 0 2 Plecotera Stoneflies 0 0 Coeleoptera 0 0 Diptera Ceratopogonidae 0 0 Chironomidae Chironomids 403 142 Gastropoda Snails 0 5 Basommatophora Ancylidae Ferrissia sp. 0 0 Bivalvia Unionidae Mussels 0 0 15 '

Table 7. (continued) Chickamauga Reservoir TRM 490.5 TRM 482 Upstream Downstream Species Mean Density Mean Density Veneroida Corbiculidae Corbicula (<10mm) 3 52 Corbicula (>10mm) 8 18 Sphaeriidae Fingernail clams 25 15 Dreissen idae Dreissena polymorpha 0 0 Number of samples 10 10 Total Mean Density/SQ Meter 487 280 Total area sampled (SQ Meters) 0.6 0.6 16

0 0 Table 8. RBI Field Scores from Data Collected During 1994-2007 at Chickamauga Reservoir Transition (TRM 490.5) and Forebay (TRM 482.0 and TRM 472.3) Sites. Site Reservoir Location 1994 1995 199.7 1999 2000 2001 2002 2003 2004 2005 2006 2007 Averag e Upstream Chickamauga TRM 490.5 33 29 31 31 23 25 25 31 31 31 27 21 28 Downstream Chickamauga TRM 482.0 23 31 29 29 33 31 31 25 29. Downstream Chickamauga TRM 472.3 31 27 29. 25 27 27 21 27 29 27 29 19 27 RBI Scores: 7-12 ("Very Poor"), 13-18 ("Poor"), 19-23 ("Fair"), 24-29 ("Good"), or 30-35 ("Excellent") Note: No data were collected for 1996 and 1998. Table 9. Electrofishing Catch Rates and Population Characteristics of Black Bass Collected During Spring Sport Fish Surveys on Chickamauga Reservoir, 1995-2007. Largest EF Catch Rate Mean Weight Bass >4 Bass >5 bass Year (no./hr.) (lbs.)  % Harvestable Ibs. lbs. (lbs.) 2007 61.1 .1.5 63.2 20 8 6.7 2006 39.4 1.3 71.7 14 7 7.1 2005 72.6 1.3 36.9 15 9 6.2 2004 40.9 1.3 60.2 13 6 6.6 2003 62.0 1.3 65.8 23 8 6.4 2002 57.4 1.1 59.4 9 4 6.6 2001 34.5 0.8 45.2 0 0 2.8 2000 34.4 1 51.2 3 0 4.8 1999 10.6 1.3 60.7 3 1 6.1 1998 37.2 1A.1 44.5 9 2 6.6 1997 40.2 1 70.1 8 4 8.7 1996 51 1.2 42.6 13 9 7.9 1995 62 1.2 61.8 28 12 8.3 17

Table 10. Black Bass Catch Per Hour Compared to Habitat Types by Location During Spring Sport Fish Surveys on Chickamauga Reservoir, 2007. Habitat Designation Reservoir and Site Good Fair Poor Chickamauga Harrison Bay. 74 (4) 62 (4) 54 (4) Sale Creek 53 (4) 64 (4) 33 (4) Skull Island 78 (2) 80 (8) 25 (2) Catch per hour = number of fish collected per hour

    = number of transects sampled at each location 18

0 Annual RFAI Scores Upstream and Downstream of SQN 60 50 40 Q o 30 20 10 0 1993 1994 1995 -.1997 1999 2000 2001 2002 2003 2004 2005 2006 2007 year Figure 1. Annual Chickamauga Reservoir RFAI scores for sample years between 1993 and 2007. 19

LENGTH FREQUENCY Largemouth bass CHICKAMAUGA -2007. 120 : . *" '::- .  : .F 7 "'.  : 100. I 80 60 40- !i :! * *!

• 1~~~~~3

Fl:  :  :: 58 58 ,

                                                                                  .    : * :::i ::::::::::::::: : : ::::::::::::::::::

2:

20 - 0-3: .5 .7 11

9 13 15 17 19 21 23 25 27

• INCH GROUP Figure 2. Length frequency distribution for largemouth bass collected from Chickamauga Reservoir (all sites) during the Spring Sport Fish Survey, 2007.

RSD VALUES (Quality) MAiNSTEM RESERVOIRS SPRING 2007 55: 50 40 I 20 1i D-sIb9iRSD 15 R-gý I i I i R-serve I Figure 3. Relative stock density values for Tennessee River reservoirs calculated from 2007 Spring Sport Fish Survey samples. 0 20

PSD VALUES: M\,AINSTEM RESERVOIRS SPRING-20,07 900 70 4

                             --. S.*
                                                                          . .7-- . ....-----

I :50-20ii . 10 SI Reseroir-Figure 4. Proportional stock density values for Tennessee River reservoirs calculated from 2007 Spring Sport Fish Survey samples. Chickamauga Wr Largemouth'bass. 2007, l Percent of Fish] 120 *350 100 *300 80 250

                                                                                                                *100J
                                                                                                                *200 80 40 20                                                                                             50 0                                                                                         0 0-7          8-11              12-14              15-19           20-24     25 +

Relative Stock Size by Inch Group Figure 5. Chickamauga Reservoir mean relative weights (Wr) for largemouth bass by RSD category and number of fish during 2007. 21

Weekly Average Flows from Watts Bar Dam, 2007 vs. Long Term (1976-2006) 50000 4500 >.,FY 2007 o.--Long Term 350000 10000 35000 iii ~i::!5 300iiiii:i0O0:: 011 I

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                                                                                                                          .... q*.-       : : ........:*..

100

                                                                                       -Mot Figure 6.       Weekly average    flows in    cubic feet     per   second    from Watts Bar Dam during October      2006 through              September            2007 with long term trend  line from 1976 through              2006.

22

TENNESSEE VALLEY AUTHORITY 0 SEQUOYAH NUCLEAR PLANT NPDES PERMIT NO. TN0026450 316(b) MONITORING PROGRAM FISH IMPINGEMENT AT SEQUOYAH NUCLEARPLANT DURING 2005 THROUGH 2007 ENVIRONMENTAL STEWARDSHIP AND POLICY 2007 S

TABLE OF CONTENTS O List of T ab les .................................................................................................................. i List of Figures .................................................. ii List of A cro ny m s ............. .................................................................. ii In tro d u c tio n .................................................. . . ...................................................... 1 P la n t D e s c rip tio n ......................................................................................................... Me th o d s ........................................................................................................................... 2 Moribund/Dead Fish .......................................................................... 2 D ata A n alys is ................................................................................................................ 2 R esults and D iscussio n .................................................................................................. 3 Summary and Conclusions ......................................... 4 References ......................................... .................... ... 5 LIST OF TABLES Table 1. List of Fish Species by Family, Scientific, and Common Name Including Numbers Collected in Impingement Samples During 2005-2007 at TVA's Sequoyah Nuclear Plant. .................................... 6

• Table 2. Estimated Annual Numbers, Biomass, and Percent'Composition of Fish Impinged by Species at Sequoyah Nuclear Plant During 2005-2007 .......... 7 Table 3. Numbers of Fish Impinged at Sequoyah Nuclear Plant by Month and Percent of Annual Total During Year-One, Year-Two, and for Both Years C om bined ....................................................................................... ......... 8 Table 4. Total Numbers of Fish Estimated Impinged by Year at Sequoyah Nuclear Plant and Numbers Following Application .of Equivalent Adult and Production Foregone Models During 2005-2007 ....................................... 8 Table 5. Percent Composition (By Number and Weight and After EA and PF Models Applied) of Major Species of Fish Impinged at Sequoyah Nuclear Plant Between December 18, 2001 and February 25, 2002 ...................... 9 Table 6. Percent Composition (By Number and After EA and PF Models Applied) of Major Species of Fish Impinged at TVA's Sequoyah Nuclear Plant During 1980-1985 and 2005-2007 ............................................................ 10 i

LIST OF FIGURES

• Figure 1. Aerial photograph of Sequoyah Nuclear Plant including CCW intake structure, skimmer wall, intake basin, and diffuser cooling pond ......... 11 Figure 2. Average daily generation (MW) and intake flow (cfs) at Sequoyah Nuclear Plant during January 2005 through January 2007 ................. 12 Figure 3. Estimated weekly fish impingement at Sequoyah Nuclear Plant during 2005-2007 ........................ I........ ............................................................... . . 13 Figure 4. Comparison of estimated weekly fish impingement at Sequoyah Nuclear Plant during historical and recent monitoring periods....................... 14 Figure 5. Ambient daily (24-hr avg) water temperature at Sequoyah Nuclear Plant intake during historical (1986-2006) and recent (2005-2007) impingement m o nito ring ............................................................................................ . . 15 LIST OF ACRONYMS AM&M Aquatic Monitoring and Management.

CCW Condenser Cooling Water CWA Clean Water Act EA Equivalent Adult EPA Environmental Protection Agency EPRI Formerly known as the Electric Power Research Institute MW Megawatt PPIC Proposal for Information Collection PF Production Foregone RFAI Reservoir Fish Assemblage Index SQN Sequoyah Nuclear Plant TDEC Tennessee Department of Environment and Conservation TRM Tennessee River Mile TVA Tennessee Valley Authority .0 ii

Introduction Sequoyah Nuclear Plant (SQN) withdraws condenser cooling water (CCW) from the Tennessee River and is subject to compliance with the Tennessee Water Quality Act and the federal Clean Water Act (CWA). Section 316(b) of the CWA requires the location, design, construction, and capacity of cooling water intake structures to reflect the best technology available for minimizing adverse environmental impact. Impingement mortality is a potentisl mechanism for adverse impacts and is defined as the condition in which fish and/or shellfish are trapped or impinged against an intake screen and often killed in the process. In response to the Environmental Protection Agency (EPA) issuance of a 2004 rule for implementing Section 316(b), a rule subsequently suspended in 2007, and in accordance with a Proposal for Information Collection submitted to Tennessee Department of Environment and Conservation (TDEC) in 2005, Tennessee Valley Authority (TVA) conducted impingement monitoring at SQN to update the impingement database for potential intake effects. This report) presents impingement mortality data collected from the CCW intake screens from January 2005 through January 2007 with comparisons to historical impingement data. Historical impingement mortality data from 1980-1985 assessed effects on the aquatic community of Chickamauga Reservoir for operational monitoring discharge permit requirements. An additional impingement study was conducted during December 2001 through February 2002, to compare peak numbers of fish impinged to historical impingement monitoring. No significant impacts were observed to the aquatic community ineither of these studies and both datasets were similar in the numbers and species impinged. . Per an agreement reached in September 2001 with TDEC, Division of Water Pollution Control, TVA performs Reservoir Fish Assemblage Index (RFAI) (Hickman and Brown 2002) sampling annually to demonstrate that SQN operation is not impacting the balanced indigenous population in Chickamauga Reservoir. The primary reason for gathering these data is to support the continuation of a Section 316(a) thermal variance for SQN. However, the RFAI monitoring also gives an indication of the overall adverse environmental impact of plant operations to the reservoir fish assemblage and benthic community, including impacts from the plant's cooling water intake. Plant Description SQN is located on the west shore of Chickamauga Reservoir at Tennessee River . Kilometer (TRK) 779.7 (TRM 484.5) (Figure 1). Construction began in 1970 and commercial operation for Unit 1 began in 1981 and Unit 2 in 1982. The two units (pressurized water reactors) have a total nameplate rating of 2,441 megawatts (MW). Natural draft cooling towers enable SQN to operate in an open or helper mode. In open mode operation, with both units at maximum power, total water demand is 72.45 m 3/s (2,558 cfs). CCW is drawn from Chickamauga Reservoir into the intake channel through an opening approximately 165 m (541 ft) long and 3 m (9.8 ft) high near the bottom of a skimmer wall situated near the river channel. This allows SQN to withdraw cooler water from the lower portion of the water column. From the intake channel, water passes through six, 3 m wide traveling screens to the intake pumps. Mesh openings on screens are 0.95 cm 2 (3/8 in2). Both units were near full load during January 2005 through January 2007 (Figure 2). Average daily generation for the two combined was 2,373 MW; Unit 1 averaged 1,186 MW and Unit 2 averaged 1,187 MW. Six intake pumps were usually in operation, resulting in an average daily intake flow of 71.8 m 3/s (2,536 cfs). Velocity at the traveling screens averaged.37 cm/sec (1.2 fps). I

Methods Impingement sampling began on January 25, 2005, and weekly samples were collected through January 15, 2007. To simplify comparisons in this report, data from January 25, 2005 through January 23, 2006 will be referred to as Year-One, and from January 30, 2006 through January 15, 2007, as Year-Two. To collect each sample, intake screens were rotated and washed on a prearranged schedule by the plant assistant unit operator to remove all fish and debris. After 24 hours, screens were again rotated and washed with Aquatic Monitoring and Management (AM&M) crew on site. Fish and debris were collected in a catch basket constructed of 9.5 mm (3/8 in) mesh located at the end of the sluice pipe where the monitoring crew removed and processed the sample. Fish were sorted from debris, identified, separated into 25 mm (1 in) length classes, enumerated, and weighed. Data were recorded by one member of the AM&M crew and checked and verified (signed) by the other for quality control. Quality Assurance/Quality Control procedures for impingement sampling (TVA 2004) were followed to ensure samples were comparable with historical impingement mortality data. Moribund/Dead Fish Fish collected from a 24-hour screen wash were usually all dead when processed. Incidental numbers of fish which appeared to have been dead for more than 24 hours (i.e., exhibiting pale gills, cloudy eyes, fungus, or partial decomposition) were not included in the sample. Also, during winter, threadfin shad occasionally suffer die-offs or stress from cold-shock and are impinged after death or in a moribund state (Griffith and Tomljanovich 1975, Griffith 1978). If these die-off incidents were observed, they were documented to specify that either all, or a portion of impinged threadfin shad collected during the sample period were impinged due to cold-shock and may not have been impinged otherwise. Any fish collected alive were returned to the reservoir after processing. Data Analysis Impingement data from weekly 24-hour impingement samples were extrapolated to provide estimates of total fish impinged by week and total for each year of study. In rare situations when less than a 24-hour sample was.possible, data were normalized to 24 hours. Historical data collected during 1981-1984 were averaged over a 52- week period, while data collected during 1985 were from January through July only. During 2001-2002, impingement data were collected from December through February and therefore represent only the winter period. To facilitate the implementation of and compliance with the EPA regulations for Section 316(b) of the CWA (Federal Register Vol. 69, No. 131; July 9, 2004), prior to its suspension by EPA, fish lost to impingement were evaluated by extrapolating the losses to equivalent reductions of adult fish, or of biomass production available to predators in the case of forage species. In conformance with methods utilized by EPA in its Technical Development Documents.in support of the Phase II Rule (EPA 2004), EPRI (Formerly known as the Electric Power Research Institute) has identified two models for extrapolating losses of fish eggs, larvae, and juveniles at intake structures to numbers or production of older fish (Barnthouse 2004). The Equivalent Adult (EA) model quantifies entrainment and impingement losses in terms of the number of fish that would have survived to a given future age. The Production Foregone (PF) model applies to forage fish species to quantify the loss from entrainment and impingement in terms of potential forage available for consumption by predators. These models require site-specific data 2

on the distribution and abundance of fish populations vulnerable to entrainment and impingement. TVA also used these models to determine the biological liability" of the CCW intake structure based on the EPA guidance developed under the suspended rule. Results and Discussion Impingement sampling at SQN from January 2005 to January 2007 resulted in collection of 2,889 fish (22 species) during Year-One and 5,766 fish (21 species) during Year-Two (Table 1). Threadfin shad were predominate (91%) in the samples, followed by bluegill (3%), freshwater drum (2%), and channel and blue catfish (1% each) (Table 2). All other species contributed less than 1% of the total number collected. Annual estimates of. number i~mpinged and corresponding biomass are compared by species and year in Table 2. Rate ofimpingement was highest during November and December during Year-One (2005-2006),. while peak impingement occurred during August, October, and November during Year-Two (2006-2007) (Table 3, Figure 3). Estimated annual impingement was calculated by extrapolating impingement rates from weekly samples. An estimated 20,223 fish were impinged during Year-One and 40,362 during Year-Two; of these, the majority was threadfin shad (Table 2). Estimated impingement during Year-Two was more than double the impingement estimate during Year-One due to collection of greater than two times more threadfin shad dui-ing Year-Two. With the exception of samples collected during 1980-1982, annual historical impingement estimates for SQNwere similar to those calculated during this study (Table 4, Figure 4). Although estimated impingement was much higher from 1980-1982, . threadfin shad accounted for the majority of fish impinged in these samples as well as in samples collected during 1983-1985. The 2001-2002 data represented samples collected only in the winter when peak numbers are typically impinged at SQN (Kay and Baxter 2002). Impingement estimates for all species, except threadfin shad, were low and consistent with the 1980-1985 historical data and with data collected during the current study. Threadfin shad was the dominant species collected during 2001-2002, comprising 97% of the total number collected and 74% of the total weight (Table 5). Gizzard shad, freshwater drum, and sunfish comprised a notable proportion of historic impingement samples following threadfin shad (Tables 5 and 6). This was similar to the dominant species collected during this study. Threadfin and/or gizzard shad typically comprise over 90% of fish impinged on cooling-water intake screens of thermal power stations in the Southeastern U. S. (EPRI 2005). They also comprise an average of 35%-56%of total fish biomass where they occur (Jenkins 1967). Threadfin shad have a high fecundity rate, move in large schools, and are intolerant to cold temperatures, often resulting in high mortality rates in winter. These traits are probably major contributing factors to the annual and seasonal fluctuation in numbers of fish impinged at SQN. A recent study by Fost (2006) indicated that cold-stressed threadfin and gizzard shad can be classified as either impaired or moribund. Impaired shad could recover if environmental conditions improved and would therefore not die if not impinged. Moribund fish on the other hand, .are assumed to not be able to recover and die regardless of impingement. Fost's data indicated that threadfin shad began to exhibit reduced or impaired swimming performance at 7.5°C (45.5-F). Plotted weekly ambient water temperatures for SQN (Figure 5) appear to be negatively _correlated with peak shad impingement as previously reported by numerous studies 3

(EPRI 2005, Griffith and Tomljanovich 1975, Griffith 1978; McLean et al., 1980). No die-offs of threadfin shad were observed at SQN during the two years of monitoring by AMM crews or were reported by power plant personnel. Application of the EA and PF models to the total numbers estimated impinged resulted in reduced numbers of fish which would have been expected to survive to either harvestable (EA) size/age or to provide forage (PF) (Table 4). This reduced number is considered the "biological liability" resulting from plant CCW impingement mortality based on the guidance developed for the now suspended 316(b) regulations. The numbers of fish representing SQN's biological liability for Year-One and Year-Two were 1,868 and 821, respectively. As part of TVA's Vital Signs Monitoring Program resident fish communities were sampled in Chickamauga Reservoir upstream TRK 789.4 (TRM 490.5) and downstream TRK 775.7 (TRM 482.0) of SQN since 1999 (Baxter and Simmons 2007). Resulting data were analyzed using a multi-metric RFAI to rate the overall health and condition of the fish community at these sampling locations. Fish communities at both sites upstream and downstream from SQN have averaged a rating of "Good" during 1999-2006, indicating that SQN is not adversely impacting the resident fish community (Baxter and Simmons 2007). Summary and Conclusions Fish impingement rates at SQN during 2005-2007 were much lower than during 1980-1981, but were similar to historical data collected from 1982-1985. Threadfin shad has

• been the dominant species impinged during all years sampled and comprised 91% of fish impinged during this study. Biological liability after EA and PF reduction was low.

Low impingement rates at SQN and "Good" RFAI scores for sites just upstream and downstream of SQN indicated that the SQN CCW intake .is not adversely impacting the Chickamauga Reservoir fish community. 4

References 'O Barnthouse, L. W. 2004. Extrapolating Impingement and Entrainment Losses to Equivalent Adults and Production Foregone. EPRI Report 1008471, July 2004. Baxter, D. S. and J. W. Simmons. 2007. Biological Monitoring of the Tennessee River Near Sequoyah Nuclear Plant Discharge.. Tennessee Valley Authority, Aquatic Monitoring and Management, Knoxville, Tennessee. EPA. 2004. NPDES - Final Regulations to Establish Requirements for Cooling Water Intake Structures at Phase II Existing Facilities; Final Rule. 69 FR No. 131, July 9, 2004. EPRI. 2005. Large-Scale Natural Mortality Events in Clupeid Fishes: A Literature Review. Palo Alto, CA. EPRI Report. Fost, B. A. 2006. Physiological & Behavioral Indicators of Shad Susceptibility to Impingement at Water Intakes. M. S. Thesis, University of Tennessee, Knoxville. 45pp. Hickman, G. and Brown, M. L. 2002. Proposed methods and endpoints for defining and assessing adverse environmental impact (AEI) on fish communities/populations in the Tennessee River reservoirs. In Defining and Assessing Adverse Environmental Impact Symposium 2001. TheScientificWorldJOURNAL 2($1), 204-218. O Griffith, J. S. and D. A. Tomljanovich. 1975. Susceptibiliiy of threadfin shad to impingement. Proceedings of the 2 9 th Annual Conference of the Southeastern Association of Game and Fish Commissioners. 223-234. Griffith. J. S. 1978. Effects of low temperature on the survival and behavior of threadfin shad, Dorosoma petenense. Transactions of the American Fisheries Society. 107(1): 63-70. Jenkins, R. M. 1967.. The influence.of some environmental factors onstanding crop and harvest of fishes in U. S. reservoirs. Pages 298-321 in Reservoir fishery resources symposium. Southern Div. Am. Fish. Soc., University of Georgia, Athens. Kay, L.K. and D. S. Baxter. 2002. Effects of impingement on the aquatic populations in Chickamauga Reservoir. Tennessee Valley Authority, Resource Stewardship, Knoxville, TN. McLean, R. B., P. T. Singley, J. S. Griffith, and M. V. McGee. 1980. Threadfin shad impingement: Effect of cold stress. NUREG/CR-1044, ORNL/NUREGiTM-340, Environmental Sciences Division, Publication No. 1495, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, 89 pp. Tennessee Valley Authority. .2004. Impingement Counts. Quality. Assurance Procedure No. RSO&E-BR-23.1 1, Rev 1. TVA River Systems Operation and Environment, Aquatic Monitoring and Management Knoxville TN. 11 pgs. 5

Table 1. List of Fish Species by Family, Scientific, and Common Name Including Numbers Collected in Impingement Samples During 2005-2007 at TVA's Sequoyah Nuclear Plant. Total Number Impin ged Family Scientific Name Common Name , Year-One Year-Two Clupeidae Alosa pseudoharengus Alewife 10 4 Dorosoma cepedianum Gizzard shad 17 25 Alosa chrysochloris Skipjack herring 10 10 Dorosoma petenense Threadfin shad 2,529 5,373 Cyprinidae Pimephalesnotatus Bluntnose minnow 0 2 Pimephalesvigilax Bullhead minnow 1 3 Moxostoma spp. Unidentified redhorse 0. 1 Notropis atherinoides Emerald shiner 1 0 Ictaluridae Ictalurus furcatus Blue catfish 25 40 Ictaluruspunctatus Channel catfish 50 32 Pylodictis olivaris Flathead catfish 3 11 Ameiurus natalis Yellow bullhead 1 0 Atherinidae Labidesthes spp. Unidentified silverside 0 1 Moronidae Morone saxatilis Striped bass 4 0 Morone chrysops White bass 2 4 Morone mississippiensis Yellow bass 24 10 Centrarchidae Lepomis spp. Unidentified sunfish 0 1 Lepomis macrochirus Bluegill 122 120 Lepomis auritus Redbreast sunfish 2 1 Lepomis microlophus Redear sunfish 1 0 Micropterussalmoides Largemouth bass 5 5 Micropteruspunctulatus SpOtted bass 1 13 Pomoxis nigromaculatus Black crappie 0 47 Pomoxis annularis White crappie 3 3 Poeciliidae Gambusia affinis Western mosquitofish 1 0 Percidae Sander canadense Sauger 1 0 Sciaenidae Aplodinotus grunniens Freshwater drum 76 60 Total Number of Fish 2,889 5,766 Total Number of Species 22 21 6

Table 2. Estimated Annual Numbers, Biomass, and Percent Composition of Fish Impinged by Species at Sequoyah Nuclear Plant During 2005-2007. __________ Estimated Number F Estimated Biomass (g) T Percent Year- Year- Year- Year- Composition A Species One Two A '.,n r One Two by Number Threadfin shad 17,703 37,611 59,612 70,539 91 Bluegill 854 840 6,636 5,054 3 Freshwater drum 532 420 63,686 28,385 2 S1 Channel catfish 350 224 78,309 25,683 1 Blue catfish 175 280 67,998 70,021 1 Black crappie 0 329 0 385 Gizzard shad 119 175 6,902 2,506 i T Yellow bass 168 70 6,545 2,779 T Skipjack herring 70 70 9,982 14,770 T Alewife 70 28 560 791 T Flathead catfish 21 77 6,391 67,326 Spotted bass 7 91 **T 700 217 Largemouth bass 35 35 231 91 T White bass 14 28 3,857 5,117 T I ýWhite crappie 21 21 91 42 T Bullhead minnow 7 21 .35 49 T Striped bass 28 0 140 0 T Redbreast sunfish 14 7 2,065 987 T T Bluntnose T minnow 0 14 14 Unidentifi'ed 0 T. redhorse 0 7 3,605 Emerald shiner 7 0 7 0 T

 .Yellow bullhead          7          0                    35            0                   T Unidentified                                                                               T silverside               0          7                     0          21 Redear sunfish           7          0                    70            0                   T Unidentified                                                                               T sunfish                  0          7                     0          28                    T Western mosquitofish             7          0                     7           0 Sauger                   7          0                  3,010          0 TOTAL           20,223    40,362    30,293    ] 316,869     298,410   307,640 7

Table 3. Numbers of Fish Impinged at Sequoyah Nuclear Plant by Month and Percent of Annual Total During Year-One, Year-Two, and for Both Years Combined. Total Number Total Number Years of Fish of Fish One and Impinged Impinged Two Month Year-One Year-Two Combined Jan 295 570 865 Feb 9 179 188 Mar 46 86 132 Apr 68 30 98 May 4 13- 17 Jun 5 5 10 Jul - 41 173 214 Aug 62 751 813 Sep 193 242 435 Oct 262. 1,515 1,777 Nov 358 1920. 2,278 Dec 1,546 282 1,828 Total 2,889 5,766 8,655 Table 4. Total Numbers of Fish Estimated Impinged by Year at Sequoyah Nuclear Plant and Numbers Following Application of Equivalent Adult and Production Foregone Models During 2005-2007.

                                      ......1~8491 1M492        982i~~19~.484                       98.. 98 ....         2G
                                                                                                           ...............      O6~2~

Extrapolated Annual Number 94,528 81,158 20,685 41,076 27,195 20,223 Imping.ed _... ........... .......... 40,362 Imi PF and ngediiiiiii~~~~iiiiiiiiiiiiiiiiiiiiiiii~~i~iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii~iiiii~~~~~~~ii~~i~~~~~ii~i~~i~i~i~iiii~~ii~~~~* Number after EA Reduction 4,851 5,843 * *;;;**** 4,162: :::::::::::: ........... 2,256 2,1 ,.. ... .......1,223

                                                                                                                   . ..... .. . 82 8

Table 5. Percent Composition (By Number and Weight and After EA and PF Models Applied) of Major Species of Fish Impinged at Sequoyah Nuclear Plant Between December 18, 2001 and February 25, 2002. Species Percent by Percent by Composition Number Weight Threadfin shad 96.98 74.09 Bluegill 0.80 0.64 Freshwater drum .0.77 14.68 Gizzard shad 0.43 1.33 Alewife 0.23 0.82 Channel catfish 0.28 1.33 Striped bass 0.24 0.46

               ýMosquitofish                    0.13            0.01 Logperch                        0.03            0.08 Flathead catfish                0.02            4168 Bluntnose minnow                0.02            0:03 Redear sunfish                  0.02            0.02 Redbreast sunfish               0.01            0.73 Largemouth bass                 0.01            0.27 White crappie                   0.01            0.83 9

Table 6. Percent Composition (By Number and After EA and PF Models Applied) of Major Species of Fish Impinged at TVA's Sequoyah Nuclear Plant During 1980-1985 and 2005-2007. 1980-1981 1981-1982 1982-1983 1983-1984 1984-1985 2005-2006 2006-2007 Species  % by  % after 0 by  % after  % after by % after b  % after %by  % after by  % after PA and PA and PA and PA and PA and PA and PA and Composition Number EF Number EF Number EF Number EF Number EF Number EF Number EF Threadfin shad 83 63 72 46 49 25 70 44 65 42 87 59 93 77 Lepomis 8 16 4 7 8 12 9 14 6 12 4 9 2 5 Gizzard.shad 4 3 9 6 22 11 2 1 8 5 1 0 0 0 Skipjack herring 0 0 0 0 1 1 3 2 4 3 0 0 0 0 Ictalurids 0 0 0 0 2 7 1 5 1 4 3 15 2 10 Freshwater drum 2 3 8 14 12 19 9 15 6 9 3 6 1 2 Spotted bass 0 0 1 2 0 0 0 0 0 0 0 0 - 1 White crappie 3 0 0 1 2 0 0 0 0 0 0 1 2 Yellow perch 3 - 6 1 6 - 4 3 0 0 0 0 Yellow/White 3 3 11 2 6 4 3 1 6 2 bass Bullhead minnow 0 0 0 0 0 0 0 0 2 1 0 0 0 0 Total 97 94 97 92 98 91 95 94. 93 96 99 95 99 99 Dash denotes not a major species during that year. 10

Wi. Figure 1. Aerial photograph of Sequoyah Nuclear Plant including CCW intake structure, skimmer wall, intake basin, and diffuser cooling pond. II

1400 1300 1200 1100 0C 1000 900 800 700

     . 600
  ,      500 400 300 200 100.

• 0 3000

 "    2500 a:   2000 I"    1500 1000 500 J   F   M   A   M  J     J A  S    0   N   .D    J  F   M  A    M    J    J   A   S   0    4 D. j 2005                                               2006                     2007 Figure 2. Average daily generation (MW) and intake flow (cfs) at Sequoyah Nuclear Plant during January 2005 through January 2007.

12

9000 8000 . 5000

  **  4000                                                             *

• i:~: ii*~*:** i:::ii

   >   ~3000          1000.......                   ................     *       *           *          .......
                                                                                                                      . . **!?:

S2000 .. ee Week Week Week Week Week Week Wek Week eek -5 1W2314 11121314 11213 Week Week Week Jn Feb Mar Apr May June July Au Sept Oct Nov I Dec  ! Jan Sample Week Figure 3. Estimated weekly fish impingement at.Sequoyah Nuclear Plant during2005-2007. 13

20000 _. .. .. " C

                                                                         ... .V .....
  = 140001  1600                       --- --                                                  ---
 .*   12000 8    0 0 0                                                   ......................................
  "*- 10000                        4000........                     ...

14000 . 26000 0.. .._. 1000 e Wek We Wek We WekWeekWeek Week Week Week Week We Jn Fb Mr Apr May Jn Juy Ag Sept Oct Nov Dec " Jan Sample Week Figure 4. Comparison of estimated weekly fish impingement at Sequoyah Nuclear Plant during historical and recent monitoring periods. 14

90 86 82 78 ____ 74 ____ ____ 70 ____ ____ __ 66 A____ _____ _____ __ 2 58 ____ I-

                                                                  -  Jan 2005 -Dec 2005 50
                                                                  -  Jan 2006 -Jan 2007
                                                                  -  Average 1981   1985 42T 38II__                                                             _    _   _

Jn Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Figure 5. Ambient daily (24-hr avg) water temperature at Sequoyah Nuclear Plant intake during historical (1981-1985) and recent (2005-2007) impingement monitoring. i5

Analysis of Sauger Spawning Success in Watts Bar Tailwater, 2001, During April Minimum Flows of 6,000 cfs by Ed Scott June 2005 Final Resource Stewardship Knoxville, Tennessee

Table of Contents Introduction I

  .Background                                                                    1 Study Area                                                                    3 Methods                                                                           3 Creel Data Results                                                            4 Gill Netting 2004 Results                                                     6 Conclusion                                                                        9 Literature Cited                                                                  10 List of Tables Table 1. Stockings of Fingerling Sauger by TWRA in Three Upper Tennessee River Reservoirs, 1987-1996 (TWRA Data).                     2 Table 2. Estimated Sauger Harvest from Chickamauga Reservoir, 2000-2003 (TWRA Data).                                                           4 List of Figures Figure 1. Watts Bar Dam discharges during late winter-early spring, 1999-2003.                                                             5 Figure 2. Percent of sauger captured by age, class in gill nets below Watts Bar Dam, 2004 (N=103).                                          7 Figure 3. Percent of sauger captured by age class in gill nets below Fort Loudoun Dam, 2004 (N=103).                                            8 Figure 4. Percent of sauger captured by age class in gill nets below Nickajack Dam, 2004 (N=132).                                                    8 i

Introduction The Tennessee Valley Authority's (TVA) River Operations attempts to maintain continuous reservoir releases between 4,000 to 8,000 cfs from Watts Bar Dam during April to benefit sauger spawning success, according to the recommendations of Yeager and Shiao (1992). TVA can provide 8,000 cfs during April of normal and wet years. During dry years, Yeager and Shiao postulated that minimunm flows of 4,000 cfs during April could also produce acceptable sauger year classes. However, it has since been found thatminimum flows of 4,000 cfs during dry years do not produce acceptable sauger spawns (Hickman and Buchanan 1995). Facing another dry spring in 2001, TVA experimented with special instantaneous releases of 6,000 cfs for the three-week period of historic peak sauger spawning (April 9-30). This report examines the relationship, between special Watts Bar Dam discharges during April 2001 and the success of sauger spawning in 2001. This information was determined by sauger age class composition in subsequent years indicated by the Tennessee Wildlife Resources Agency (TWRA) creel surveys 2000-2003 and gill netting sauger age classes observed in 2004.

Background

During the 1980s, the Tennessee Valley experienced the most severe, extended period of drought on record (Ruane et al. 1991). Low average rainfall meant low reservoir levels and limited discharges. As a result of the drought, sauger populations plummeted to critically low levels, leading the State of Tennessee to identify the Chickamauga Reservoir sauger population as a sport fish species of "special concern" in 1986. Shortly thereafter, TVA partnered with the TWRA to determine the level of the sauger population in Chickamauga Reservoir and identify potential negative impacts caused by the operation of Watts Bar and/or Sequoyah nuclear plants. It was later determined that nuclear plant operations were not affecting the sauger population. However, the drought conditions of the late 1980's, especially the low flows from Watts Bar Dam during April, the month sauger typically spawn, were identified as the primary cause of sauger declines in Chickamauga Reservoir (Hevel 1988). Instream flow incremental methodology determined that instantaneous minimum discharges of 8,000 cfs from Watts Bar Dam during April should be adequate to produce successful sauger year classes (Yeager and Shiao 1992). In an attempt to supplement the Chickamauga Reservoir population, TWRA stocked nearly 191,000 sauger fingerlings into the reservoir in May 1990 (Table 1) at a cost of $30,000. This effort boosted the 1991 population and was thought to be very effective in establishing a year class (Hickman and Buchanan 1995). Additional stockings of sauger fingerlings into Chickamauga Reservoir occurred in 1991 and 1995, as well as stockings into adjacent reservoirs. These stocking efforts, however, were likely just temporary fixes to make up for lost spawning success, as spawning success was later determined to be directly related to the level and regularity of releases through Watts Bar Dam during the nighttime hours when sauger are most actively spawning. 1

Table 1. Stockings of Fingerling Sauger by TWRA in Three Upper Tennessee River Reservoirs, 1987-96 (TWRA data). Reservoir Year Number of Sauger Stocked Chickamauga 1990 190,912 1991 14,400

                                ;1995                     45,784 all years.                  251,096 Watts Bar              1990                     110,624 1991                      65,467 1995                      42,214 1996                     176,052 2004                     118,000 all years                   512,357 Ft. Loudoun            1987                      10,114 Totals             1987-2004                    773,567 Unfortunately, maintaining instantaneous minimum flows of 8,000 cfs during April has not been possible during drought years of recent history. Consequently, TWRA has had difficulty maintaining sauger fisheries, as conveyed in a recent article in the Knoxville newspaper:
       "Walleye, sauger a priority for area lakes" Bob Hodge, sports writer, Knoxville News-Sentinel, June 27, 2004.
       "Walleye and sauger have moved to the top of a priority list in recent years because of problems with natural reproduction. Although the hatchery-raised fish are doing well, Smith (Mike Smith, TWRA, Eagle Bend Hatchery) said sauger reproduction has been below average for several years." "Three years of drought had resulted in poor year classes," Smith said. "We had a heck of a time getting brood fish this year because the year classes have been so depressed."

Watts Bar received 118,000 sauger this spring. TWRA stocking records, dating back to 1953, indicate sauger were never in low enough abundance to warrant stocking until 1986, when they were stocked into Douglas Reservoir. However, following the drought of the mid to late 1980's and the declines in sauger abundance, which was also documented by TVA below Watts Bar Dam, stockings of fingerling sauger were made into Chickamauga, Watts Bar, and Fort Loudoun reservoirs (Table 1). Sauger declines were not limited to reservoirs on the Tennessee River, as TWRA also stocked sauger in Cumberland River reservoirs in Tennessee. Sauger were listed as a species of "special concern" by the State of Tennessee in 1986, and in spite of several years of stocking fingerlings, sauger continue to be in need of 2

special management by TWRA. They are currently being cultured at all five TWRA hatcheries across the state (Mike Smith, TWRA Eagle Bend Hatchery, personal communication). Study Area Chickamauga Dam, located at Tennessee River mile (TRRM) 471 in Hamilton County, Tennessee, impounds 59 miles of river upstream to Watts Bar Dam. Chickamauga Reservoir has a total surface area of 14,326 hectares. Depths range from 5 meters just below Watts Bar Dam to 25 meters in the deepest part of the channel during the summer. The Hiwassee River, with it's confluence at TRM 500, is the only major tributary to this reservoir. Flows to upper Chickamauga Reservoir are mainly controlled by hydroelectric turbine discharges from Watts Bar Dam, with spillway releases occurring infrequently. During the 1986-1987 studies, Hunter*Shoals (TRM 521-522) was identified as the critical spawning habitat for the Chickamauga sauger population. Approximately one mile in length, it is the largest shoal area in the Chickamauga section of the Tennessee River. It is located approximately seven miles downstream of Watts Bar Nuclear Plant (WBN). The substrate consists mainly of small gravel, but also includes areas with larger gravel and cobble (Hickman et al. 1989). Methods Originally, the success of the 2001 year class was to be evaluated by experimental gill net catches of sauger below Watts Bar Dam in winter/spring of 2002. However this was not possible due to unusually high discharges during the time sauger would have been congregated below the dam. So gill net surveys were delayed until 2003. But a fire in the control room at Watts Bar Dam crippled operation of the Watts Bar turbines for many months, including the time gill net samples would have been collectedin 2003. All the water passing the dam during this time was routed through the spillways, making unsafe work conditions below the dam. A fallback .attempt to evaluate the 2001 year class in 2003 was made using TWRA creel census results for Chickamauga Reservoir, 2000-2003. Inferences on the strength of the 2001 year class were. drawn from four parameters of the creel data: total number caught, total number harvested, percent of caught fish released, and average weight. In 2004, after two years of missed gill netting opportunities, favorable sampling conditions occurred in the tailwaters below Watts Bar Dam. Experimental gill nets consisting of five 6.1 m panels (25.4, 38.1, 50.8, 63.5, and 76.2 mm bar mesh size) were set perpendicular to the shoreline in the tailwater below Watts Bar Dam from mid-January to mid-April. Netting was conducted at night when sauger are most active. The duration of each net set was between one and two hours to reduce catch mortality. Experimental gill netting was conducted directly below Watts Bar Dam for the most part, but some nets were set as far downstream as the WBN intake. Otoliths were taken from 103 individuals for positive age verification by. Steve Sammons, a research assistant at Auburn University. The otoliths were magnified and aged in 3

whole view, unless more than 2 annular rings @'ere.detected. In those cases, the otoliths were sectioned, ground smooth using 600-grit sandpaper, and then read in transverse view using a fiber optic light. Age classes were determined by the number of annular rings observed, similar to the way trees are aged by counting their rings. Gill netting and otolith collection fromn the nearby tajilwaters of Fort Loudoun and Nickajack dams \wre ulso conducted in early 2004 fo0Vr MI nMrelated study. Age composition of sauger collected in those surveys were compared to the findings of the present study. Creel Data Results Because insufficient numbers of sauger were collected in gill net samples below Watts Bar Dam during 2002 and 2003, inferences from TWRA creel surveys on Chickamauga Reservoir were drawn to evaluate sauger abundance and year class strength (Table 2). Table 2. Estimated sauger harvest from Chickamauga Reservoir, 2000-2003 (TWRA data). Percent of

     *Year           Total number        Total number                         Average weight caught            harvested          caught fish        r (ibs.)

released 2000 18,784 7,160 61.9 1.46 2001 15,265 5,518 63.9 1.45 2002 8,245 4,071 50.6 1.65 2003 1,991 837 58.0 1.67 Sauger fishing is highly seasonal, beginning in December and ending in March, when sauger migrate to the headwaters of Chickamauga Reservoir below Watts Bar Dam before the spring spawning season. Most sauger are caught during January and February, as in 1992 (TWRA 1993). To help maintain the fishery, TWRA enforces a 15" minimum size limit, which allows them at least one spawning season before being harvested. Most fish are in their third growing season when they reach legal size. Since sauger are sought mostly for food, as opposed to a catch-and-release fishery, the majority of those released are under legal size. The percentage of caught fish released (Table 2) gives an approximation of one and two-year old fish in the Chickamauga Reservoir sauger fishery. Average weight of harvested sauger also indicates the year class composition of the fishery among years. Angler exploitation rates of sauger were reported as high as 36 percent below Pickwick Dam in west Tennessee (Pegg, et al. 1996), and high rates may also occur below Watts Bar Dam. Creel statistics for 2000 and 2001 are somewhat similar in total number caught, total number harvested, percent of caught fish released, and average weight. This indicates the yearclass composition of harvested sauger from Chickamauga Reservoir were basically the same; although the abundance may have been slightly more in 2000. Nearly two-thirds of the sauger caught were released, implying they were of sub-legal size (i.e., 4

one and two-year old fish). The abundance of sub-legal sauger caught indicates relative 0 spawning success during the previous two years. But in 2002, creel statistics show a change in year class composition and a decline in recruitment of smaller, younger fish to the fishery. That decline can be largely traced to the relative weakness of the 1999 year class of sauger, which was attributed to the minimum April 1999 flows of4,000 cfs from Watts Bar Dam (Figure 1). The totWi n200 catch was approximately half those of the previous two years, and the average size was larger. Furthenrore, the lower percentage of caught and released fish in 2002 implies a decline in abundance of sub-legal sauger, which would include the 2001 year class. If future data confirm this to be true, then the 6,000 cfs maintained for the last three weeks in April 2001 was insufficient to produce a strong sauger year class. One cautionary note on using creel data to evaluate sauger abundance is necessary. Since sauger are primarily harvested during the two month period preceding their spawning season, inclement weather or flow conditions (such as high, muddy discharges) at that time could hinder sauger fishing and produce creel statistics that do not accurately reflect the true abundance of sauger in Chickamauga Reservoir. Also note that flows in February 2002 were not, excessive (Figure 1), and the creel statistics for that year, as discussed above, should be accurate. The same is not true for Watts Bar Dam discharges in 2003 because flows during late February and early March often exceeded 100,000 cfs. Much of this was spillway 0 Watts Bar Dam Discharges 1000000Feb-May, 1999-2003

        *U 100000              -x   -_                   _  _   _ _   _   _  _ _ _  _ _ _

1000 0 ~.~ Q .IOU 'i 100 IijI 2/1 2121 3/2 4/1 4/21 51 5/31 Date

                                -1999     -   2000 -2001             ::2002 -2003
 . Figure 1. Watts Bar Dam discharges during late winter-early spring, 1999-2003.

5

discharge, which presented sauger fishermen with difficult circumstances and might 0 account for the low sauger catch that year. The total number caught in 2003 was only 1,991 fish, which was less than one-fourth the 2002 estimated catch and about 10 percent of the 2000 catch. The percent of caught and released fish in 2003 increased to 58.0 percent, indicating the recruitment of smaller fish compared to 2002 (50.6 percent). These smaller fish likely originated from the 2001 year classes. A higher pcrcentage olI released fish would be expectcd had the 2001 ,ear class ofsauger been larger. Since the average weight did not decline, the harvested catch likely included newly recruited fish from the 2000 year class, whose smaller size was offset by older and larger fish from the 1998 and earlier year classes. In summary, assessment of 2001 sauger spawning success during three weeks of 6,000 cfs minimum flows during the spawning season was not possible using gill net information collected in 2002 or 2003 due to unusual flow conditions. Instead, inferences were made on the relative success of the 2001 spawn using TWRA creel information. Those data indicate the 2001 spawn was relatively poor. However, creel data in 2000-2002 indicate that even during the recent drought, the sauger fishery did not crash, as it did during the drought years of the late 1980's, before April minimum flows were maintained at Watts Bar Dam. In other words, the minimum flows of 4,000-6,000 cfs at the dam during the recent drought years helped maintain a limited degree of sauger spawning success. Gill Netting 2004 Results S Favorable conditions for gill netting in Watts Bar Tailwater occurred during the late winter and early spring in 2004. A total of 142.5 net hours between January 21 and March 23 produced 127 sauger, with an overall average catch rate of 0.89 sauger per hour. Note that this catch rate is less than half of the 1986 catch rate (2.14 fish per hour), which at the time was so alarmingly low that the State of Tennessee listed the Chickamauga sauger as a species of "special concern." Sauger continue a tenuous existence in Tennessee. Otoliths from 103 of the 2004 fish were examined for positive age class identification. Age class analysis confirmed a-very weak 2001 year class, as only 4.7 % (5 fish) of the sauger collected in 2004 were produced in 2001 (Figure 2). A weak2001 year class agrees with the findings of the creel survey analysis discussed previously. While three years of natural and fishing mortality explains some of the decline of the 2001 year class,' it appears there simply were not many fish produced in 2001 to begin with. The majority of sauger collected in 2004 resulted from 2002, a year of high flows during the spawning season (Figure 1). The 2002 year class (Age 2 fish) dominated the sauger population of Chickamauga Reservoir by comprising over 75% of the population (Figure 2). Age 1 sauger were the next most abundant age class (8.5%), and were not fully represented in the 2004 catch because not all Age I sauger appear in the spawning population. Nevertheless, their relative abundance indicates a reasonable year class was 6

00. 7 0.0 .. .......

                                       .      .. . . .. ... ..........         ..77... ... . ....

C 4M 2.0 30.0 1~0.0 0.0 1 2 3 4 5 6 7 8 9

                                                      ýAOgelass Figure 2. Percent of sauger captured by age class in gill nets below Watts Bar Dam, 2004 (N= 103).

produced during the high flows of 2003. It still bears reiteration that the Chickamiauga Reservoir sauger population is depressed compared with their abundance in the early 1980's. A few fish older than Age 3 were found in 2004, although little can be said of such low numbers. A relatively strong 1998 year class was indicated by Age 6 fish (5.7%), considering several years of high mortality rates. During April 1998l minimum Watts Bar flows of 8,000 cfs were maintained (except for two days of 7,3 00 and 7,400 in early April), and a minor flood event occurred during the second half April with daily average flows in excess of 50,000 cfs. Age class composition in the Fort Loudoun Tailwaters (Figure 3) was similar to that found in the Watts Bar Taiowaters. As in the Chickamauga population, the 2001 year class (age class 3) in Watts Bar Reservoir, the next reservoir upstream, was very weak, representing less than 10 percent of the catch. Over 50 percent of the sauger sampled below Fort Loudoun Dam were produced in 2003, indicating spawning conditions were' relatively good there that year. Over 20 percent of sauger collected below' Fort Loudoun( Dam were age class 2. Other age classes present were 4, 6, and 7. 7

0 60.0 40.0 L-L(.. CL 30.0

a,:

20.0 10.0 0.0 1 2 3 4 5 6 7 8 Age Class Figure 3. Percent of sauger captured by age class in gill nets below Fort Loudoun Dam, 2004 (N=103). 70.0 60.0 50.0 40.0 a. 30.0 20.0 10.0

                                                  -3               45 Ag~e Class Figure 4. Percent of sauger captured by age class in gill nets below Nickajack Dam, 2004 (N=-132).

8

Weakness of the 2001 year class was also noted below Nickajack Dam. Sauger of age class 3 represented only 2.3 percent of the catch (Figure 4). Two-year old sauger from the Nickajack Tailwaters made up nearly 60 percent of the total catch, while one-year old fish were nearly 40 percent. Less than 2 percent of the Nickajack tai]water sauger were age class 4 and no older fish were observed. Conclishon Sauger spawning success is.definitely related to flows during the spawning season. Experimental Watts Bar discharges of 6,000 cfs during three weeks in April 2001 were not enough to produce a strong year class of Chickamauga sauger. More flow is better, as shown from the 2002 and 2003 year classes below Watts Bar Dam. However, April minimum flows of at least 4-6000 cfs at Watts Bar Dam during the recent drought years did maintain the sauger population, according to creel data in 2000-2002 and gill netting data in 2004. The sauger fishery did not crash, as it did during the drought years of the late 1980s. Spawning conditions in 2002 and 2003 were much better, according to age class I and 2 fish found below Watts Bar Dam, as well as Fort Loudoun and Nickajack. TWRA will continue to stock fingerling sauger in Tennessee reservoirs as necessary to maintain sauger fisheries. TVA should assist state fisheries managers whenever possible via reservoir operations. Instantaneous minimum flows of 8,000 cfs from Watts Bar Dam during April should be provided each year, if at all possible. Experimental flows of 4,000 and 6,000 cfs during three weeks in April were insufficient to produce strong year classes of this state-imperiled species. Providing instantaneous 8,000 cfs flows throughout the entire month would minimize water temperature variations year to year, ensuring beneficial flows at the right temperature for sauger spawning. These special flows should be provided until the sauger population below Watts Bar Dam recovers to at least the abundance present in 1986, when special regulatory attention was given. Maintaining instantaneous minimum flows below other Tennessee River mainstem dams would also improve sauger spawning success throughout the system, if feasible. Minimum flows as provided by turbine pulsing at Douglas and Cherokee dams by TVA's Reservoir Releases Improvement program since 1987 should also help maintain and enhance sauger fisheries in the upper Tennessee River. 0 9

Literature Cited Hevel, Kerry. W. 1988. Survey of the population dynamics ofsauger (Stizostedion cwiadense) in Chickamauga Reservoir, Tennessee - 1986 and 1987. Office of Natural Resources and Economic Development, Tennessee Valley Authority, Knoxville; Tennessee. 1-1 ickn. ~.a*,~irv D. and Johnny P. Buchain. 1995. Chickamauga Reservoir s~1ger investigation 1993-1995, Final proj ect report. Resource Group, Water Management, Tennessee Valley Authority, Norris, Tennessee. Hickman, Gary D., Kerry W. Hevel,. and Edwin M. Scott, Jr. 1989. Density, movement patterns, and spawning characteristics of sauger (Stizostedion canadense) in Chickamauga Reservoir, 198,9. River Basin Operations, Water Resources, Tennessee Valley Authority, Norris, Tennessee. Pegg, Mark A., James B. Layzer, and Phillip W. Bettoli. 1996. Angler exploitation of anchor-tagged saugers in the lower Tennessee River. North American Journal of Fisheries Management 16:218-222. Ruane, Richard J., David J. Bruggink, and Bruce L. Yeager. 1991. Environmental impacts of drought in the Tennessee Valley. Pages 692-697. In Environmental Engineering Proceedings, 1991 Specialty Conference/EE Div./ASCE. Reno, Nevada, July 8-10, 1991. Tennessee Wildlife Resources Agency (TWRA). 1993. 1992 TWRA creel survey. Fisheries Report 93-14. Tennessee Wildlife Resources Agency, Nashville, Tennessee. Yeager, Bruce L., and Ming C. Shiao. 1992. Recommendation and implementation of special seasonal flow releases to enhance sauger spawning in Watts Bar Tailwater. Water Resources, Tennessee, Valley Authority, Chattanooga, Tennessee. 10

0 January 7, 2009 SStephanie A. Howard, SB 2A-SQN-.. INFORMATION ON RESERVOIR OPERATIONS FOR SEQUOYAH NUCLEAR PLANT (SQN) NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM (NPDES) PERMIT APPLICATION Part IlI, Section F of NPDES Permit TN0026450 for SQN effective September 1, 2005, states that "ForSection316(a), the permittee shall analyze previous and new data to determine whether significant changes have occurred in plant operation, reservoiroperation or instream biology that would necessitate the need for changes in the thermal variance." The purpose of this memo is to provide information related to changes in reservoir operations. In May 2004, TVA implemented changes in the operation of the Tennessee River and its tributaries based on the Reservoir Operations Study (ROS). The Deputy Commissioner of the

• Tennessee Department of Environment and Conservation and the Director of the Tennessee Division of Water Pollution Control participated on the interagency team that assisted TVA with this study.

As part of the ROS, the following basic changes were made that impact Chickamauga Reservoir: TVA no longer targets specific summer pool elevations in its ten large tributary storage reservoirs. Instead, TVA uses weekly average system flow requirements to limit the drawdown of the tributary reservoirs and to meet specific obligations for navigation, water supply, waste assimilation, and power generation. The weekly average system minimum flow requirement from June 1 through Labor Day, measured at Chickamauga Dam, is determined by the volume of water in storage in the ten large tributary reservoirs compared to a system minimum operating guide (SMOG). The SMOG is a seasonal system storage guide curve.. If the volume of water in storage is above the SMOG, the weekly average minimum flow from Chickamauga Dam is increased each week, starting at 14,000 cubic feet persecond (cfs) the first week of June and reaching 25,000 cfs for the last week of July. Beginning August 1 and continuing through Labor Day, the weekly average minimum flow requirement from Chickamauga Dam is 29,000 cfs. These minimum flow requirements are higher than the previous operating policy. If the volume of water in storage is below the SMOG, the weekly average minimum flow requirement from Chickamauga Dam between June 1 and July 31 is 13,000 cfs, and from August 1 through Labor Day it is 25,000 cfs. For June and July the minimum flow requirement is similar to that of the previous operating policy; however, for August it is 12,000. cfs higher than the previous operating policy.

• • Stephanie A. Howard Page 2 January 7, 2009
• The pool in Chickamauga Reservoir is now held within its summer operating zone through Labor Day. For the previous operating policy, the summer pool was held within its operating zone only through August 1.
• Based on the results of the flood risk analysis, and to better protect against flooding for all main river projects (with the most benefits realized at Chattanooga), the filling of the three Upper mainstem projects (Fort Loudon/Tellico, Watts Bar, and Chickamauga) is delayed to reach the summer operating zone by early May, rather than mid-April.

The impact of these changes on the operation of Sequoyah was analyzed as a part of the ROS. The analyses assumed that SQN will always operate in a manner that maintains the thermal' criteria as specified in the NPDES permit, with no changes in the thermal variance. That is, the analyses found that with the ROS operating policy, successful operation of SQN requires a continuation of the thermal variance. In practice, drought conditions that have persisted in the Tennessee Valley for the past three-years have further demonstrated the need to continue the thermal variance. The variance has allowed SQN to operate during periods of low river flow in the cooler months of the year when such conditions, without the variance, would have otherwise placed the reliability of the plant at significant risk. Charles L. Bach General Manager, River Scheduling River Operations WT 10C-K PNH:JGP cc: Janet C. Herrin, WT 1OD-K Robin E. Kirsch, WT 10C-K Paul N. Hopping, WT l0B-K R. Ann Hurt, SB 2A-SQN EDMS, WT 10C-K 2

TENNESSEE VALLEY AUTHORITY River Operations Ambient Temperature and Mixing Zone Studies for Sequoyah Nuclear Plant as Required by NPDES Permit No. TN0026450 of September 2005 WR2009-1-45-151 Prepared by Paul N. Hopping Kevin M. Stewart Colleen R. Montgomery John M. Higgins Knoxville, Tennessee January 2009

EXECUTIVE

SUMMARY

The August 2001 National Pollutant Discharge Elimination System (NPDES) Permit for Sequoyah Nuclear Plant (SQN) required a number of studies related to Section 316 of the Clean Water Act. Due to the short span of the 2001 permit, these studies were carried forward in the current NPDES permit, effective September 2005. The studies are related to the plant diffuser discharge to the Tennessee River, identified in the NPDES permit as Outfall 101. This report provides data, analyses, and conclusions for two of these studies-the ambient temperature study and the mixing zone study. Due to the evolution in understanding of the hydrothermal and biological characteristics of Chickamauga Reservoir, as well as the operational aspects of the nuclear plant and river system, modifications have been necessary over the years in the thermal criteria and monitoring of Outfall 101. A chronology of these modifications is summarized herein. The most recent modification, implemented as part of the August 2001 permit, involved changing the period of averaging for the downstream temperature Td and temperature rise AT from hourly to 24-hours. This was done because changes in river flow due to hydro peaking operations were causing unexpected swings in the river temperature that could require a near immediate response by SQN. Because SQN does not control hydro operations and because the time required to plan and safely implement procedures for cooling tower operation and/or changes in unit generation can be in excess of the time required to respond to swings in the river temperature, hourly averaging

• placed the plant in situations where thermal violations possibly could not be averted. Previous studies showed that a change from hourly averaging to 24-hour averaging would have no adverse impact on the hydrothermal and biological aspects of Chickamauga Reservoir. However, as part of this change, two special studies were added in the NPDES permit of 2001-one to confirm the adequacy of the ambient temperature measurement and one to confirm the configuration of the mixing zone.

As background for the summary that follows, the basic thermal limits for Outfall 101 specified in the current NPDES permit include: a maximum 24-hour average downstream temperature Td of 86.9°F (30.5°C), a maximum 24-hour average temperature rise AT of 5.4 FP (3.0 C0 ) for April through October, a maximum 24-hour average temperature rise AT of 9.0 FP (5.0 C0 ) for November through March, and a maximum hourly average temperature rate-of-change dTd/dt of

 +/-3.6 F/hour (+/-2 C°/hour). The November through March limit for AT was obtained by a 316(a) variance request in 1989. Additional details associated with these limits are provided in this report.

Ambient Temperature Study For the ambient temperature study the permit states "TVA shall conduct a study to evaluate the spatial distribution of water temperature in the overbank and main channel regions of Chickamauga Reservoir upstream of the plant diffuser. The study shall supplement data from previous evaluations, as needed, by measuring temperature profiles at selected sites in the

• reservoir. The study shall consider both winter and summer hydrothermal regimes, and both 1-hour and 24-hour averaging. The goal of the study is to determine the major factors i

contributing to the interaction between main channel and overbank flows, the impacts on water temperatures in the thermal mixing zone, and optimal location of monitors to record the ambient temperature. At the time of the 2001 permit, the ambient temperature for the mixing zone was measured at Station 13. This station is situated on the plant intake skimmer wall and about 1.1 miles upstream of the discharge diffusers. The results of previous evaluations indicated that this location was adequate for the ambient temperature measurement. However, to confirm the earlier evaluations and to collect data to better satisfy the goal of the ambient temperature study, three ambient temperature deployments were performed. Two of the deployments included the installation of temporary temperature stations at a number of sites in the main channel and overbanks upstream of the mixing zone. The first, for summer conditions, was performed from July 23 through August 4, 2003. The second, for winter conditions, was performed from January 21 through February 2, 2004. During these deployments, rainfall was abundant, resulting in high daily average river flows-typically between 25,000 cfs and 40,000 cfs. Although the river flow included periods with heavy peaking operations, the temperatures measured at Station 13 and other sites further upstream were within normal expectations. That is, the first two deployments suggested that Station 13 was adequate for measuring the ambient temperature. In March 2006, the current drought first began to influence conditions in Chickamauga Reservoir, compelling TVA to reduce daily average flows in the river to levels as low as

• 4000 cfs. At about the same time, Station 13 began recording water temperatures that were unexpectedly high, even for periods of intense solar heating. Since the plant diffuser discharge is the only other nearby source of heat in the reservoir, it was immediately suspected that thermal effluent from the mixing zone was migrating upstream far enough to reach Station 13. This, of course, reduces the plant-induced temperature rise and underestimates the impact of the SQN thermal discharge on the receiving water. As a result, on March 29, the ambient temperature measurement was changed to a location 6.8 miles upstream of the discharge diffusers. The new location, labeled Station 14, was approved by TDEC in a meeting on April 7, 2006.

The third ambient temperature deployment was performed from May 18 through June 2, 2006 to confirm the adequacy of the location of Station 14. In contrast to the first two deployments, the third deployment included temperature readings along the center of the river, starting from the mixing zone and extending upstream to Station 14. The measurements found that Station 14 was free of any impacts due to the local buildup of heat arising from the SQN thermal discharge, at least for the prevailing river conditions during the deployment. With this background, the following items summarize key conclusions from the ambient temperature study: The major factors contributing to the interaction between main channel and overbank flows in Chickamauga Reservoir include meteorology, hydrology, river geomorphology, and in the vicinity of SQN, the action of the plant diffusers. In the deployments, these factors resulted in temperature differences between the main channel and overbanks areas in the vicinity of SQN as large as 3 F° (1.7 C0 ). ii

 " Velocity gradients created by boundary resistance, shoreline irregularities, and bends in the river create recirculation zones and mixing in the overbanks that can transport heat upstream, even though the average flow in the reservoir is in the downstream direction.

• At river discharges below the range of from 17,000 cfs to 25,000 cfs, the action of the SQN diffusers can promote recirculation between the main channel and overbank regions of the flow. This occurs as a result of the high velocity jets issuing from the diffuser, which entrain ambient flow in the river. If the amount of flow entrained by the jets is larger than the flow in the river, part of the effluent mixture will be transported through the sides of the mixing zone, feeding into the overbanks.
• Deployments involving temperature measurements along the center of the river suggest that for lower river flow, the upstream migration of heat from the SQN mixing zone can extend further upstream as a result of peaking operations compared to that which occurs for steady operation of the river.

 " Prior to the NPDES permit of August 2001, the only recognized mechanism responsible for the upstream migration of thermal effluent from SQN was mean flow advection as a result of reservoir sloshing from peaking operations. Previous evaluations suggested that by this mechanism, the upstream migration from the diffusers would not travel more than half the distance between the mixing zone and Station 13. However, the studies summarized herein indicate that heat from the mixing zone can be carried upstream beyond Station 13.

O Temperature measurements along the center of the river suggest that Station 14 is free from any effects of the SQN thermal effluent for steady river flows as low as about 6000 cfs and for peaking operations with daily average river flows as low as about 13,000 cfs. This covers the range of river operations experienced since April 2006 of the current drought.

 " There presently is no reliable method to estimate the additional warming in the mixing zone due to the impact of solar heating in the overbanks verses that due to recirculation of the plant thermal effluent. Consequently, SQN is operated in a manner to keep the total temperature rise below the NPDES standard, whether or not the source of the temperature rise is from the diffuser discharge or from a combination of the diffuser discharge and overbank heating.
 " Exceedance probabilities suggest that over most of the range of observed ambient temperatures, there is very little difference in the duration of occurrence for hourly averaging verses 24-hour averaging. Near the annual maximum and minimum temperatures, the difference between the hourly average and 24-hour average is less than 0.5 F° at an exceedance of 0.5 percent (i.e., a total of about 48 hours over the entire year).

iii

Mixing Zone Study W For the mixing zone study the permit states "TVA shall conduct a study to evaluate the dynamic behavior of thermal plume from the plant diffuser. The study shall examine the justificationfor the existing mixing zone and supplement data from previous evaluations, as needed, by measuring temperature profiles at selected sites in and about the mixing zone. The study shall consider both winter and summer hydrothermal regimes, and both 1-hour and 24-hour averaging. The goal of the study is to better determine the impact of hydro peaking operations on the behavior of the thermalplume, and to determine if there is any need to redefine the extent of the mixing zone." The NPDES permit specifies the existing mixing zone as an area 750 feet wide and extending 1500 feet downstream and 275 feet upstream of the diffusers. The justification for the mixing zone is based on a physical model study of the discharge diffusers, which examined the thermal effluent over a wide range of plant and river conditions, including reverse flows in the reservoir. Between the startup of SQN and the NPDES permit of August 2001, eleven field surveys were performed to verify the compliance model and document the extent of the thermal effluent from the diffusers. All of these surveys confirmed the adequacy of the mixing zone. However, most of the surveys encompassed only short periods of time (e.g., hours) with near-steady conditions. To examine the dynamic behavior of the thermal effluent and evaluate hourly verses 24-hour averaging, three new mixing zone temperature deployments were conducted.

• The deployments for the mixing zone included temporary temperature stations around the entire perimeter of the mixing zone. In contrast to previous mixing zone surveys, the deployments provided measurements allowing evaluations of temperatures concurrently for all faces of the mixing zone and over periods long enough to examine the dynamic behavior of the mixing zone based on hourly averaging and 24-hour averaging. In addition, measurements also were made across the mixing zone to map the approximate spatial distribution of the thermal effluent during periods of near steady flow.

The mixing zone deployment for summer conditions was performed from August 11 through August 24, 2004. Hydro peaking operations were common in this period, with daily average river flows as low as 10,000 cfs and as high as 40,000 cfs. The deployment for winter conditions was performed from January 21 through February 2, 2004. The river flow during the winter deployment was high-initially near 40,000 cfs. However, special hydro operations were arranged to produce one event with reverse river flow, and one day with a river flow of about 18,000 cfs for measurements with steady conditions. The third deployment was performed to check the mixing zone after the onset of the current drought. The deployment was between September 19 and September 22, 2007. The river flow was steady at about 9000 cfs. In addition to these three deployments, an abbreviated survey of the mixing zone was conducted on November 4, 2007. This survey was conducted as part of an NPDES requirement to confirm the calibration of the compliance model for downstream river temperature. The river flow for this survey was about 6000 cfs and extremely steady, as was the

• ambient river temperature. For these reasons, the results of the November 4, 2007 survey are expected to be representative of the 24-hour average behavior.

iv

With this background, the following items summarize key conclusions from the mixing zone

• study:

 " For high river flows, above about 25,000 cfs, almost all of the thermal effluent in the diffuser mixing zone is assimilated in the downstream direction. Temperatures in the mixing zone tend to be suppressed.

• For river flows in the range of about 17,000 cfs to 25,000 cfs, part of the thermal effluent begins to be assimilated upstream and laterally through the sides of the mixing zone.

Temperatures in the mixing zone tend to become elevated. Areas of recirculation can begin to form between the mixing zone and adjacent shorelines. These can be responsible for feeding thermal effluent into the overbanks. For river flows below about 17,000 cfs, temperatures in the mixing zone become further elevated and the quantity of thermal effluent assimilated through the sides and upstream of the mixing zone increases.

 "   The thermal effluent in the mixing zone appears to shifts towards the right side of the mixing zone for high river flow and towards the left side of the mixing zone for low river flow (i.e.,

facing downstream).

 "   The impact of peaking operations causes the thermal effluent in the diffuser mixing zone to transition between the basic behaviors described above. During the peak when river flows are high (e.g., above 25,000 cfs), all of the diffuser effluent is assimilated downstream and water temperatures in the mixing zone are suppressed. During offpeak hours when low and reverse river flows occur (e.g., less than 17,000 cfs), the thermal effluent is assimilated in all directions and water temperatures in the mixing zone are elevated. Periods of reverse river flow likely provide the greatest assimilation of effluent in the upstream direction, but such periods are short, usually less than three hours per event.

• The impact of peaking operations is basically the same for winter and summer conditions.
• Measurements found that the average temperature along the downstream face of the mixing zone, which is used to calibrate the NPDES compliance model, is usually among the highest of all the faces and provides a good estimate of the average temperature around the perimeter of the mixing zone. In the new deployments, the average temperatures for the individual faces, as well as that for all faces combined, were contained within the NPDES limits for the downstream temperature and temperature rise. That is, the mixing zone study provided no indication that the mixing zone needs to be redefined at this time.

Exceedance probabilities suggest that over most the range of observed downstream mixing zone temperatures, there is very little difference in the duration of occurrence for hourly averaging verses 24-hour averaging. Near the annual maximum and minimum temperatures, the difference between the hourly average and 24-hour average is again less than 0.5 F° at an exceedance of 0.5 percent (i.e., a total of about 48 hours over the entire year).

• Observations in the mixing zone study, as well as those in the ambient temperature study, recognize that at low river flow, effluent from the mixing zone can become re-entrained into the v

water diluting the diffuser plume. This local buildup of heat in the river was not included in the

• version of the compliance model in use before the drought. To correct this situation, changes have been made in the model to simulate the local warming of the water entering the mixing zone at low river flow.

Overall Conclusions Examining the ambient temperature study and mixing zone study collectively, the following overall conclusions are provided:

 "   Since the startup of the plant in 1981, SQN has always sought to expand TVA's understanding of the hydrothermal aspects of the combined operation of the Tennessee River and the plant. SQN has regularly conducted comprehensive surveys of the plant thermal effluent, averaging about one survey every for every 18 months of operation.

• As a result of the studies summarized herein, changes have been successfully made in the location of the ambient temperature measurement and in the mixing zone compliance model.

These changes were needed to account for the local buildup of heat in the river that occurs at low river flow.

• Field testing and operating experience suggest that based on current procedures to monitor and operate the plant, the ambient temperature measurement and mixing zone configuration are adequate for steady river flows as low as about 6000 cfs. For peaking operations, the ambient temperature measurement is estimated to be adequate for daily average river flows as low as about 13,000 cfs and the mixing zone for daily average flows as low as about 10,000 cfs. If TVA anticipates operating at conditions below these levels, additional measurements will be taken to continue to confirm the adequacy of the ambient temperature measurement and the mixing zone.
• On an annual basis, exceedance probabilities suggest that there is little difference between the duration and frequency of ambient and mixing zone temperatures monitored using 24 hour averaging verses hourly averaging. NPDES monitoring with 24-hour averaging for the downstream temperature Td and the temperature rise AT has been in effect since August 2001 with no evidence of any adverse impact to the balanced indigenous population of shellfish, fish, and wildlife in Chickamauga Reservoir. Furthermore, the results of studies summarized herein suggest that based on current procedures for monitoring the plant thermal compliance, it is very likely that any changes in the plant operation to protect the NPDES limits based on 24-hour averaging will also attenuate the most extreme hourly average temperature excursions. That is, the most extreme hourly average temperature excursions usually coincide with the most extreme 24-hour average temperatures, wherein cooling tower operation or changes in unit generation are needed to maintain NPDES compliance for Td or AT. For these reasons, and since 24-hour averaging is more synchronous with the time required to make safe changes in plant operation, SQN believes that the NPDES requirements for the downstream temperature and temperature rise can safely continue to be based on 24 hour averaging.

vi

CONTENTS Pg EXECUTIVE

SUMMARY

CONTENTS ............................................................................................. vii LIST OF FIGURES..................................................................................... ix LIST OF TABLES ...................................................................................... Xi

1.0 INTRODUCTION

...............................................................................            1

2.0 BACKGROUND

THROUGH 2001........................................................... 3 2.1 SQN Thermal Criteria and Monitoring Requirements ...................................... 3 2.2 SQN Ambient Temperature ................................................................... 9 2.3 SQN Mixing Zone............................................................................. 13 3.0 PREVIOUS STUDIES THROUGH 2003................................................... 14

• 3.1 Physical Model Study ........................................................................ 14 3.2 Field Studies ................................................................................... 15 3.2.1 July 24, 1997 Study ........................................................................ 24 3.2.2 March 24, 1999 Study ..................................................................... 25 3.2.3 August 2, 2000 Study....................................................................... 27 3.2.4 Studies in 2002 and 2003.................................................................. 27 4.0 NEW STUDIES IN 2004 THROUGH 2007................................................ 32 4.1 Ambient Temperature Study ................................................................. 32 4.].] Summer Deployment July 23 through August 4, 2003 .................................. 34 4.1.2 Winter Deployment January 21 through February2, 2004 ............................ 47 4.1.3 Relocation of Ambient Monitoring Station, March 2006............................... 59 4.1.4 Third Deployment May 18 through June 2, 2006 ....................................... 62 4.1.5 Hourly and 24-HourAveraging........................................................... 68 4.2 Mixing Zone Study ........................................................................... 71 4.2.1 Basic HydrothermalAspects of Diffuser Discharge and Effluent Plume ............. 71

*4.2.2             Monitoring of Diffuser Mixing Zone......................................................          74 4.2.3    Summer Deployment August I11 through August 24, 2004 .............................              76 Vii

CONTENTS CONTINUED 4.2.4 Winter Deployment February12 through February23, 2004.............................. 83 4.2.5 Third Deployment September 19 through September 22, 2007............................ 89 4.2.6 Other Mixing Zone Studies ................................................................................... 94 4.2.7 Hourly and 24-HourAveraging............................................................................ 98 4.2.8 Modified Compliance Model For Downstream River Temperature........................ 101

5.0 CONCLUSION

S ............................................................................................................ 105 5.1 Am bient Tem perature Study ........................................................................................ 105 5.2 Mixing Z one Study ...................................................................................................... 108 5.3 O verall C om ments ....................................................................................................... 111

6.0 REFERENCES

............................................................................................................... 113 0

0 viii

LIST OF FIGURES 0 Page Figure 1. Water Temperature Station Locations for Initial Operation of SQN ..................... 4 Figure 2. Basic Parameters for SQN Hydrothermal Model ................................................... 5 Figure 3. Water Temperature Stations for SQN Computed Compliance .............................. 5 Figure 4. Hydrothermal Event with Spiking in Ambient Temperature at Station 13 ........... 10 Figure 5. Main Channel and Overbank Areas near SQN ...................................................... 12 Figure 6. Water Temperature Measurements from Field Study of July 24, 1981 ................ 17 Figure 7. Water Temperature Measurements from Field Study of May 11, 1983 ................ 20 Figure 8. W ater Temperatures from July 24, 1997 Study .................................................... 28 Figure 9. W ater Temperatures from March 24, 1999 Study ................................................. 29 Figure 10. Water Temperatures from August 2, 2000 Study, Pass 1...................................... 30 Figure 11. Water Temperatures from August 2, 2000 Study, Pass 2 ...................................... 31 Figure 12. Sampling Locations For Ambient Temperature Study .......................................... 33 Figure 13. Schematic of HOBOTM Water Temperature Monitoring Station .......................... 34 O Figure 14. Main Channel and Overbank Stations MC01 and OB01 for Summer Deployment ..38 Figure 15. Main Channel and Overbank Stations MC02 and OB02 for Summer Deployment ..39 Figure 16. Main Channel and Overbank Stations MC03 and OB03 for Summer Deployment ..40 Figure 17. Main Channel and Overbank Stations MC04 and OB04 for Summer Deployment ..41 Figure 18. Main Channel and Overbank Stations MC05 and OB05 for Summer Deployment ..42 Figure 19. Main Channel and Overbank Stations MC12, OB 11, and Station 13 for Summer D eploym ent ................................................................................................................ 43 Figure 20. Main Channel and Overbank Stations MC10 and OB 10 for Summer Deployment ..44 Figure 21. Main Channel and Overbank Stations MC08 and OB08 for Summer Deployment ..45 Figure 22. Main Channel and Overbank Stations MC09 and OB09 for Summer Deployment ..46 Figure 23. Main Channel and Overbank Stations MCO1 and OBO1 for Winter Deployment ..... 50 Figure 24. Main Channel and Overbank Stations MC02 and OB02 for Winter Deployment ..... 51 Figure 25. Main Channel and Overbank Stations MC03 and OB03 for Winter Deployment ..... 52 Figure 26. Main Channel and Overbank Stations MC04 and OB04 for Winter Deployment ..... 53 Figure 27. Main Channel and Overbank Stations MC05 and OB05 for Winter Deployment ..... 54 Figure 28. Main Channel and Overbank Stations MC 12, OB 11, and Station 13 for Winter 0 D eploym ent ................................................................................................................ 55 ix

LIST OF FIGURES CONTINUED Pa e Figure 29. Main Channel and Overbank Stations MC10 and OB10 for Winter Deployment ..... 56 Figure 30. Main Channel and Overbank Stations MC08 and OB08 for Winter Deployment ..... 57 Figure 31. Main Channel and Overbank Stations MC09 and OB09 for Winter Deployment ..... 58 Figure 32 Releases Upstream (Watts Bar) and Downstream (Chickamauga) of SQN .......... 60 Figure 33. SQN Ambient River Temperatures Measured at Station 13 on March 29, 2006 ....... 61 Figure 34. Station 14 Floating W ater Temperature Station .................................................... 61 Figure 35. Location of New Ambient Temperature Station ................................................... 62 Figure 36. Temperature Rise along Center of River for Steady River Flow of 8000 cfs ..... 66 Figure 37. Temperature Rise along Center of River for Steady River Flow of 18,000 cfs ......... 66 Figure 38. Upstream Migration of Thermal Effluent for Steady, Low River Flow ................ 67 Figure 39. Temperature Rise along Center of River following Peaking Operations at 14 ,000 cfs ................................................................................................................... 68 Figure 40. Computed River Flow at SQN for 2007 ............................................................... 69

• Figure 41 Ambient Water Temperature Measured at SQN Station 14 for 2007 ................... 70 Figure 42. Exceedance Probability for Ambient Water Temperature at Station 14 for 2007 ...... 70 Figure 43. Basic Design Features of Sequoyah Diffusers ...................................................... 71 Figure 44. Basic Behavior of Effl uent Plume ........................................................................ 72 Figure 45. Recirculation Zones Created By Diffuser Mixing ................................................. 74 Figure 46. Location of Stations for Mixing Zone Temperature Measurements ..................... 76 Figure 47. Mixing Zone Temperatures For Summer Deployment .......................................... 80 Figure 48. Mixing Zone Temperatures For Summer Deployment Showing Temperature Rise..81 Figure 49. Water Temperature Measurements at 5-foot depth for August 22, 2004 .............. 82 Figure 50. Water Temperature Measurements at 5-foot depth for August 23, 2004 .............. 82 Figure 51. Mixing Zone Temperatures For Winter Deployment ............................................. 86 Figure 52. Mixing Zone Temperatures For Winter Deployment Showing Temperature Rise .... 87 Figure 53. Temperature Rise Measurements at 5-foot depth for February 22, 2004 .............. 88 Figure 54. Temperature Rise Measurements at 5-foot depth for February 23, 2004 .............. 88 Figure 55. Mixing Zone Temperatures For Third Deployment ............................................. 92 Figure 56. Mixing Zone Temperatures For Third Deployment Showing Temperature Rise ...... 93 Figure 57. Water Temperature Measurements at 5-foot depth for September 21, 2008 ...... 94 x

LIST OF FIGURES CONTINUED 0 Pag~e Figure 58. Temperatures for Mixing Zone Survey of November 4, 2007 .............................. 96 Figure 59. RTD Measurements at 5-Foot Depth Around Mixing Zone for November 4, 2007..97 Figure 60. Computed River Flow at SQN for 2008 .............................. 99 Figure 61. Computed Temperature at Downstream End of Mixing Zone for 2008 .................. 100 Figure 62. Exceedance Probability for Computed Temperature at Downstream End of M ixing Zone for 2008 .............................................................................................. 100 Figure 63. Two-Dimensional Plane Buoyant Jet Model for a Submerged Diffuser .................. 101 LIST OF TABLES Page Table 1. Field Studies for Sequoyah Nuclear Plant 16 Table 2. Field Studies by TVA QA Plan of 1987 22 0 xi

AMBIENT TEMPERATURE AND MIXING ZONE STUDIES FOR SEQUOYAH NUCLEAR PLANT AS REQUIRED BY NPDES PERMIT NO. TN0026450 OF SEPTEMBER 2005

1.0 INTRODUCTION

Part III, Section F of the National Pollutant Discharge Elimination System (NPDES) Permit TN0026450 for Sequoyah Nuclear Plant (SQN) of August 2001 included a number of requirements related to the evaluation of Section 316 of the Clean Water Act. Due to the short span of the 2001 permit, these requirements were carried forward in the current NPDES permit, effective September 2005. The requirements address questions concerning Outfall 101, which includes, among other constituents, the discharge of waste heat into Chickamauga Reservoir through two submerged, multiport diffusers in the main channel of the Tennessee River. This report summarizes studies that have been completed by TVA to fulfill two of the Section F requirements. These are as follows: To determine the adequacy of measurements for ambient river temperature, TVA shall conduct a study to evaluate the spatial distributionof water temperature in the overbank and main channel regions of ChickamaugaReservoir upstream of the plant diffuser. The study shall supplement data from previous evaluations, as needed, by measuring temperature profiles at selected sites in the reservoir. The study shall consider both winter and summer hydrothermal regimes, and both 1-hour and 24-hour averaging. The goal of the study is to determine the majorfactors contributing to the interactionbetween main channel and overbank flows, the impacts on water temperatures in the thermal mixing zone, and optimal location of monitors to record the ambient temperature. To determine the adequacy of the mixing zone, TVA shall conduct a study to evaluate the dynamic behavior of thermal plume from the plant diffuser. The study shall examine the justificationfor the existing mixing zone and supplement datafrom previous evaluations, as needed, by measuring temperature profiles at selected sites in and about the mixing zone. The study shall consider both winter and summer hydrothermal regimes, and both 1-hour and 24-hour averaging. The goal of the study is to better determine the impact of hydro peaking operationson the behavior of the thermalplume, and to determine if there is any need to redefine the extent of the mixing zone. The first of these studies is identified as the ambient temperaturestudy. The second is identified as the mixing zone study. As background for the supplemental data that have been collected for the ambient temperature and mixing zone studies, a review is first provided of the SQN thermal criteria and monitoring requirements, ambient temperature measurement, and mixing zone requirements. This review includes work from the startup of the plant through the NPDES permit of August 2001. For this same period, a summary of the original diffuser physical model study and subsequent field verification studies also is given. The results of new studies targeting the specific issues identified in Section F are then presented. These include additional field 1

deployments to measure water temperatures upstream of the plant and around the diffuser mixing zone. As a result of the new studies, changes have been made in the methods of monitoring SQN thermal compliance, including the location of the ambient temperature monitor and the formulation of the numerical model for the thermal plume in the mixing zone. These charges are presented herein alongside the results of the new studies. S 2

2.0 BACKGROUND

THROUGH 2001 2.1 SQN Thermal Criteria and Monitoring Requirements Operating SQN in a fashion to fulfill TVA's goals of supplying low-cost reliable power and supporting a thriving river system is no trivial task. The awareness and understanding of the ever changing biological, hydrothermal, and operational aspects of Chickamauga Reservoir and SQN continue to evolve. It is no surprise, therefore, that modifications of the SQN thermal criteria and monitoring requirements have been needed to accommodate issues important to both TVA and the regulatory community. The initial thermal criteria for SQN were based on temperature limits adopted by the Tennessee Water Quality Board in December 1971 and approved by the Environmental Protection Agency (EPA) in June 1972. The criteria include:

      " A maximum instream temperature Td of 86.9°F (30.5°C).

• A maximum instream temperature rise AT of 5.4 FP (3.0 C0 ).

      " A maximum instream temperature rate-of-change dTd/dt of +/-3.6 F/hour (+/-2 C°/hour).

• The monitoring requirements for these criteria were first specified in the Sequoyah NPDES permit effective July 1979. The criteria were applied to the area outside of a mixing zone of size appropriate for the multiport diffusers. The requirement for temperature rise was applied between this area and a suitable upstream control point, the latter which defines the ambient temperature for the thermal discharge. The locations of monitoring points, shown in Figure 1, were as recommended by TVA in February 1979 (TVA, 1979a). The upstream control point included a water temperature station located at the skimmer wall of the plant intake, Station 13.

The area outside of the mixing zone was monitored by two water temperature stations located near the downstream corners of the mixing zone, Stations 8 and 11. The temperature at these stations was determined as the average of individual sensor readings at water depths of about 3 feet, 5 feet, and 7 feet (1.0 meter, 1.5 meter, and 2.0 meter). The thermal criteria did not identify a "time scale" in computing the temperature parameters. However, TVA agreed to parameters (i.e., Td, AT, and dTd/dt) that were determined as hourly averages, computed every 15 minutes by averaging the current and previous four 15-minute readings. In the early eighties an issue arose concerning the validity of the downstream temperature measurements at Station 8 and Station 11. Field data found that temperatures from these monitors were, at times, not representative of the cross-sectional average temperature at the end of the mixing zone. Since the mixing zone resides in the navigation channel, instream temperature stations cannot be placed at locations optimal for obtaining a good cross-sectional average temperature. To reduce the uncertainty of the instream mounting of Figure 1 vs. the

• actual impact of the SQN thermal discharge, a hydrothermal model capable of predicting the temperature at the downstream end of the mixing zone was developed. The basic requirements 3

for the model were outlined in the NPDES permit effective April 1983, which stated "upon

• approval by the Director,Water Management Division, and the State Director,compliance with the river limitations shall be monitored by means of a numerical model that solves the thermo-hydrodynamic equations governing the flow and thermal conditions in the reservoir." Field tests were conducted to verify the diffuser performance for the model and the model subsequently was found to provide a better representation of the downstream temperature than that of the instream monitors (TVA, 1983). In March 1984, approval was granted for TVA to use the numerical model to monitor compliance of the NPDES temperature requirements.

t Monitor No. Figure 1. Water Temperature Station Locations for Initial Operation of SQN (after TVA, 1979b) Briefly, the hydrothermal model solves the fundamental equations for the conservation of mass, momentum, and thermal energy to determine the average temperature along the centerline of the thermal discharge from a submerged diffuser in a stratified, ambient cross flow. The basic parameters required by the original model are shown in Figure 2, and include the temperature and flow of water in the river, the depth of flow of the river, and the temperature and flow from SQN. Values for these parameters are determined from measurements at the SQN water temperature stations, shown in Figure 3, and at the hydro plants immediately upstream and downstream of SQN. The upstream ambient river temperature TR was measured at Station 13. The measurements at the 3-foot, 5-foot, and 7-foot depths are averaged to obtain the upstream temperature Tu. Note that Tu is required to determine the temperature rise AT=Td-Tu. 4

T. Td -- ý ý Tu-~j Td 7 ~ A

              -*-           -OYYI R   / 5feet                     7 /      5 feet DR
                                 ,. /
                             ,. /

OSQN,TSQN Bottom diffusers V El I Figure 2. Basic Parameters for SQN Hydrothermal Model Figure 3. Water Temperature Stations for SQN Computed Compliance 5

9 The temperature of the effluent from Sequoyah TSQN is measured at the entrance of the diffuser conduits at Station 12, located in a pond situated between the outlet of the plant and the river. In addition to temperature, Stations 12 and 13 also contain a stage recorder to measure, respectively, the water surface elevation in the diffuser pond and the water surface elevation in the river. The water surface elevation in the river is used to determine the depth of flow at the diffusers DR. The discharge of effluent from Sequoyah QSQN is determined based on a calibrated rating curve giving QSQN as a function of the difference in water surface elevation between the diffuser pond and river. The river discharge at Sequoyah QR is computed based on a calibrated, one-dimensional flow model of Chickamauga Reservoir. The flow model requires discharges measured at the Watts Bar Hydro plant (WBH), located 45.5 miles upstream of SQN, and the Chickamauga Hydro plant, located 13.5 miles downstream of SQN. All of this information is collected over communication links by an Environmental Data Station (EDS) located at Sequoyah. The model computes the compliance temperatures Td, AT, and dTd/dt every 15 minutes. Hourly average values are computed as previously summarized. Additional details about the model formulation are presented later in this report. In implementing the "computed compliance," Station 11 was removed from service. Station 8, however, was retained to provide a backup for the downstream temperature measurement in the event of failure of the computed compliance system and to verify general trends determined by the hydrothermal model. In this arrangement it is emphasized that because Station 8 resides on the outer edge of the mixing zone, it can be dominated by processes significantly different from

• those in the mixing zone, such as heating and cooling in overbank and embayments areas in the immediate vicinity of the station.

The next significant issue to emerge occurred in the mid-eighties and involved problems related to the cooling towers. During periods of low flow in the wintertime, operation of the cooling towers was needed to prevent exceedances of the criterion for maximum temperature rise (i.e., 5.4 F/3.0 C'). However, due to cold air temperatures, use of the cooling towers during these periods induced severe ice damage in the towers, which is costly and jeopardized the availability of the towers for subsequent months, particularly the summer. This prompted a 316(a) demonstrative request in 1989 to increase the AT limits during the months November through March from 5.4 F to 9.0 F or 3.0 C0 to 5.0 C0 (TVA, 1989). TVA analyses found that this increase would not adversely impact the balanced, indigenous population of shellfish, fish, and wildlife in Chickamauga Reservoir. The request to raise the temperature rise limit was accepted by EPA and the State of Tennessee in the Sequoyah NPDES permit effective September 1993. With this, the thermal criteria became:

        "   A maximum instream temperature Td of 86.9°F (30.5°C).
        "   A maximum instream temperature rise AT of 9.0 F (5.0 C°) for November thru March (i.e., "wintertime" operation).
        "   A maximum instream temperature rise AT of 5.4 F (3.0 C0 ) for April thru October (i.e.,
            "summertime" operation).

6

• A maximum instream temperature rate-of-change dTd/dt of +/-3.6 F/hour (+/-2 C°/hour).

The overall monitoring requirements for the new criteria remained largely unchanged. That is, the hydrothermal modeling system was considered adequate for determining the temperature in the mixing zone and the thermal criteria continued to be interpreted on an hourly average basis. The most recent issues emerged in the mid-nineties and involved the effects on Sequoyah of certain unsteady behaviors in Chickamauga Reservoir. The behaviors are caused primarily by two processes. The first is the daily variation of river flow that occurs as a normal part of peaking operations at TVA hydro plants, and the second is fluctuations in the ambient river temperature. Depending on the exact circumstances, these processes can give rise to individual events threatening the limit for Td, AT, or dTd/dt. Those for dTd/dt are the most problematic and occur in both the winter and summer. In the winter, cooling tower operation cannot reliably be used to control dTd/dt, again due to potential icing. In the summer, the dTd/dt events occur in the ambient temperature upstream of the plant and cannot be controlled by tower operation. Events threatening the limits for Td are related to the unpredictability of summertime upward swings in the ambient temperature and the rate of onset of these swings. In the hydrothermal model, the impact of the waste heat from Sequoyah is superimposed on the ambient temperature to yield the downstream temperature. Thus, unexpected increases in the upstream temperature also occur in the downstream temperature. In some cases, the cooling towers can be used to control fluctuations in downstream temperature; but, due to the inherent complexity of the equipment, the towers cannot be brought into service on short notice, as may be required to respond to the rapid onset of temperature increases. Problems for AT occur primarily in April and May, when river flows are restricted to help fill TVA reservoirs. In light of the inability of SQN to fully control these events, and to avoid derating the plant, special operations of the river system were regularly used to maintain compliance of the thermal criteria. Due to the large extent of these special operations, a supplemental 316(a) demonstration was performed in 1996 to make additional changes in the thermal criteria and monitoring requirements (TVA, 1996). The proposed changes included thefollowing:

     " Increase the maximum instream temperature rate-of-change dTd/dt from +/-3.6 F/hour to
          +/-9.0 F/hour (from +/-2 C°/hour to +/-5 C0 /hour).
     " Include April and May in the period of wintertime operation, allowing a maximum instream temperature rise AT of 9.0 F (5.0 C0 ) for November thru May.

• Monitor the instream temperature Td and instream temperature rise AT based on a 24-hour average.

As before, TVA analyses found that the proposed changes would not adversely impact shellfish, fish, and wildlife in Chickamauga Reservoir. In ensuing debate, however, the first two items were denied by the State. The third item, though, was accepted, because it did not involve an

• additional change in the thermal standards via the 316(a) process. That is, the magnitudes of the limits for instream temperature Td and instream temperature rise AT remained the same as 7

before-only the time scale for computing the parameters was adjusted. Since this did not resolve the problems related to the temperature rate-of-change, and since SQN was not directly responsible for unsteady behaviors resulting from daily variations in river flow, TVA proposed an alternate method for monitoring dTd/dt. In the method, unexpected swings in ambient reservoir conditions are handled by using 24-hour average values in the hydrothermal model for the river conditions, specifically, the ambient river temperature, river discharge, and river depth (i.e., TR, QR, and DR in Figure 2). The impact of short-term variations in the SQN thermal discharge is added to the 24-hour average river conditions by using 15-minute values for the flow and temperature of the Sequoyah effluent (i.e., QSQN and TSQN in Figure 2) in computing dTd/dt. The hourly average temperature rate-of-change due to these variations is computed, as before, using the current and previous four 15-minute dTd/dt values. Monitoring dTd/dt by 24-hour averaging of the river conditions was approved by the State, subject to the hydrothermal studies summarized herein. It is important to note that this type of averaging is used only for the computation of dTd/dt. For Td and AT, 15-minute values are yet determined solely from 15-minute values of the model parameters identified in Figure 2. It again is emphasized that in approving the changes for Td, AT, and dTd/dt there were no additional changes in the fundamental thermal criteria. That is, the supplemental 316(a) proposed in 1996 was not invoked-changes in the requirements for monitoring were made outside of the 316(a) process. With these changes, the basic thermal criteria and monitoring requirements found in the Sequoyah NPDES permit effective August 2001 included the following: 0 . A maximum instream temperature Td of 86.9°F (30.5°C).

       " A maximum instream temperature rise AT of 9.0 P (5.0 C°) for November thru March.
       " A maximum instream temperature rise AT of 5.4 P (3.0 C0 ) for April thru October.

• A maximum instream temperature rate-of-change dTd/dt of +/-3.6 P/hour (+/-2 C0/hour).
• Td and AT are to be monitored based on 24-hour average values, calculated every 15-minutes by averaging the current 15-minute values with the previous ninety-six 15-minute values.

       " dTd/dt is to be monitored based on an hourly average value, calculated every 15 minutes by averaging the current 15-minute value with the previous four 15-minute values, where each 15-minute value is determined based on the 24-hour average river conditions (i.e.,

TR, QR, and DR) and current 15-minute plant conditions (i.e., QSQN and TsQN). In addition to the above, it is noted that other concerns over the years have led to other specific monitoring requirements. For example, the following items also are found in the current NPDES permit: 8

     " To allow operation of the plant when the ambient temperature exceeds the thermal criteria, when the 24-hour average upstream temperature Tu exceeds 84.9°F (29.4'C), the 24-hour average downstream temperature Td may exceed 86.90 F (30.50 C), if the plant is operating the cooling towers with at least three lift pumps per operating unit.

• In no case shall the 1-hour average downstream temperature Td exceed 93.0°F (33.9°C) without consent of the permitting authority.

2.2 SQN Ambient Temperature The specifications for monitoring the SQN upstream ambient temperature were originally recommended by TVA in February 1979 (TVA, 1979a). The State granted approval of the recommendations in the NPDES permit effective July 1979. As previously summarized, the ambient temperature was measured at Station 13, located on the reservoir-side of the plant intake skimmer wall, and was computed as the average of sensor readings at depths of 3 feet, 5 feet, and 7 feet. At that time, Station 13 obviously was considered to be beyond the zone of impact of the plant thermal discharge and a good location for measurement of the temperature of water entering the plant. Station 13 also borders the main channel of the river, which provides the main source of water for dilution of the thermal effluent from the plant diffusers (see Figure 3). In the NPDES permit effective April 1983, the State emphasized the requirement that "under no conditions shall the thermal plume be allowed to reach the ambient temperature recorder." If

• the plume reached the ambient temperature recorder, the temperature rise AT would be biased low, thereby underestimating the impact of the SQN thermal discharge on Chickamauga Reservoir. Subsequent analyses by TVA indicated that the probability of a surface thermal wedge from the diffusers extending upstream 3000 feet, about one-half the distance to the Station 13 monitor, is of magnitude 0.0008 percent. This conclusion was based on an analysis of the computed magnitude and duration of reverse flow events at the site due to hydro peaking operations of the river. As presented later with the new studies, this analysis has been found to be erroneous. This is because the analysis assumed the upstream propagation of heated effluent from the diffusers was limited by the extent of a thermal wedge, which was assumed to expand at a rate roughly equivalent to the cross-sectional average velocity in the river. In reality, TVA has learned that other transport mechanisms exist that can spread residual heat from the mixing zone significantly further upstream than the extent of a thermal wedge.

Problems with swings in the ambient temperature occur during high river flow. An example event with swings in the ambient temperature is given in Figure 4. The figure shows the calculated river discharge at SQN along with the measured ambient temperature at Station 13 and the resulting ambient temperature rate-of-change. The event occurred the first two days of June 2000. The temperatures include both 15-minute and hourly average data. It is emphasized that in June 2000 the plant was operating under the NPDES permit effective September 1993 and did not include 24-hour averaging of ambient river conditions for the temperature rate-of-change. During afternoon peaking operations, when the river flow exceeds about 30,000 cfs, it can be seen that the ambient temperature begins to fluctuate in a manner creating 15-minute variations

• that at times surpass +/-2 F' (1.1 C°). On June 2, the resulting hourly average value hit the 9

compliance limit of +/-3.6 P/hour (+/-2 C°/hour). These ambient variations, in turn, were superimposed by the hydrothermal model on the compliance parameters computed at the downstream end of the mixing zone. 50 40 o 30 z C 20 10

             -20
            ~ 10
             -20 83 82 81 Z

80 79 0 E 78 77 76 75 74 10

          "     8

• 6 (U
• 4 U

s 2 0 N 0

        *     -2
        *.    -4 E
       *      -6
       *      -8 E
       < -10 5/31/00              6/1/00                   6/2/00                   6/3/00 Figure 4. Hydrothermal Event with Spiking in Ambient Temperature at Station 13 10

In part, it appears that troublesome swings in the ambient temperature occur when the river discharge exceeds about 38,000 cfs. It is speculated that the reason why ambient spiking had not been problematic in the years prior to the mid-nineties is related to the condition of the hydro plant at Chickamauga Dam. Over the past 50 years, plant equipment had degraded to a point where the maximum discharge through the hydraulic turbines was limited to about 38,000 cfs. Between 1994 and 1997 the hydro units and other related equipment were upgraded, allowing the Chickamauga discharge to match levels similar to the capacity of the original turbines, over 45,000 cfs. This, in turn, has allegedly resulted in ambient temperature events that until recently had never been observed in the life of SQN. Several processes are envisioned as potentially playing a role in ambient temperature spiking. In the summer, late afternoon solar heating can cause the water temperature in the near surface region of the flow to become much warmer than the water at a depth of 5 feet. Higher levels of flow turbulence caused by high river discharges can mix the surface water downward to the 5-foot depth and create intermittent temperature fluctuations. In the winter, a similar phenomenon can occur with surface cooling, which is exacerbated by the fact that such cooling is innately unstable (i.e., cool water underlain by warmer water is unstable). In addition to vertical variations in temperature, fluctuations also can occur as a result of lateral differences between the main channel and overbanks. Water in shallow overbank areas will heat up and cool off much faster than water in the deep main channel. At high river flow, mixing between the main channel and overbank areas can entrain parcels of water from the overbanks, again creating intermittent fluctuations. As shown in Figure 5, shallow overbank areas prevail in the areas surrounding SQN, particularly on the east side of the reservoir across from and upstream of the plant. Both Station 13 and Station 8 are positioned in regions that could potentially be influenced by turbulent interactions between the main channel and overbanks. Whereas the above processes depend on turbulent interactions, unexpected increases in the ambient temperature might also occur due to advection from different areas by the mean flow. For example, as a part of routine river operations, Chickamauga Reservoir can undergo daily and weekly cycles of drawdown and filling. A common occurrence is for the water level to drop (i.e., drawdown) during afternoon peaking operations and rise (i.e., fill) during early morning periods of low flow. Weekly variations occur for mosquito control. In these processes, water will fill into and drain out of the overbanks, embayment areas, and creeks. In the summer, water from these areas will likely be warmer than that in the main channel, and vice versa in the winter. When parcels of water from these areas are transported past a monitoring station, the temperature, subsequently, will fluctuate. In the summer, Soddy Creek and Opossum Creek, located upstream of SQN, are potential sources for parcels of warm water in Chickamauga Reservoir. Another mean flow process is related to the curvature of the river. Such curvature, which exists in the vicinity of SQN, will cause secondary currents to develop in directions transverse to the centerline of the river. This again can potentially cause the exchange of water between the main channel and overbanks, yielding fluctuations in the ambient temperature. Overall, depending on the magnitude and extent of these processes, it may be that another more

• suitable location exists to measure the ambient temperature. This indeed is what has been discovered in recent work, as presented later with the new studies.

11

0 N Denotes Reservoir areas of water depth less than 20 feet DIFFUSERS Imixing Zone

                                                      ýStation 81 Figure 5. Main Channel and Overbank Areas near SQN (after TVA, 1978) 12

2.3 SQN Mixing Zone The mixing zone for SQN was proposed by TVA based on a physical model study of the discharge diffusers conducted at the TVA Engineering Laboratory (TVA, 1978). The initial recommendation included a zone 750 feet wide and 1500 feet long, extending downstream from the diffusers over the entire depth of flow. In subsequent discussions with EPA and the State, the extent of the mixing zone was modified to provide for upstream excursions of a thermal wedge on the water surface during low and reverse river flow events. The permit effective July 1979 thus provided an additional area extending 275 feet upstream of the diffusers with a depth that varied linearly from the water surface at 275 feet to the top of the diffuser pipes. This mixing zone has been certified by the State from 1979 to the current NPDES permit. The present permit also specifies that if SQN is operated in closed mode, the mixing zone shall include the intake forebay of the plant (see Figure 3). In general, prior to the current permit, there have been no issues concerning the definition of the mixing zone for SQN. As summarized later, studies have been performed regularly to evaluate water temperatures in and around the mixing zone. Whereas most of these studies have examined conditions with steady flows, recent concerns are more focused on the behavior of the thermal effluent for unsteady conditions stemming from hydro peaking operations. ,S 13

3.0 PREVIOUS STUDIES THROUGH 2003 3.1 Physical Model Study In general, releasing heat through multiport diffusers situated on the bottom of the river hastens mixing of the effluent with the receiving water and significantly reduces the required size of the mixing zone (i.e., compared to side-channel discharges into the surface layer of the river, which were common at that time). The design of the submerged multiport diffusers for SQN was based on experience developed in the design of diffusers for the TVA Browns Ferry Nuclear Plant (BFN). The BFN analyses included a two-dimensional physical model study at the Massachusetts Institute of Technology (Harleman et al., 1968) and a three-dimensional physical model study at the TVA Engineering Laboratory (TVA, 1972). Despite the confidence of the BFN work, a physical model study also was conducted for the proposed SQN diffusers (TVA, 1978 and TVA, 1979c). The objectives of the SQN model were to evaluate the performance of the diffusers for the specific conditions expected at the site and to determine empirical coefficients required to estimate the ambient entrainment and dilution of the diffuser discharge. The model was constructed at a scale of 1:90 in a 10-foot wide flume at the TVA Engineering Laboratory. The model corresponded to a section of the main channel about 900 feet wide and 6300 feet long. The overbanks were not modeled because it was estimated that they contribute little flow for the dilution of the thermal discharge. Also, because secondary

• currents were estimated to have only a minor impact on mixing, the model was constructed as a straight section of river rather than a curved channel. The model did include, however, an underwater dam located about 350 feet upstream of the diffusers.

The SQN model included tests for prototype river flows varying between -5000 cfs (reverse flow) to 30,000 cfs and diffuser discharges corresponding to both one- and two-unit operation of the plant. Effluent temperatures were tested at 10 F0 , 20 F0 , 30 F0 above the ambient (upstream) temperature (5.56 C', 11.11 C0 , 16.67 C0 ). Roughly 100 thermistors were used to measure water temperatures in the model. The major findings from the model include the following:

      " For the cases examined, the initial temperature difference between the ambient and SQN effluent is quickly reduced by the action of the diffuser jets to values below the thermal criteria (i.e., 5.4 F/3.0 C°).
     "   A stratified surface layer is formed in nearly all the cases tested and extends upstream of the diffusers.
      " The major portion of the jet mixing occurs within 500 feet downstream of the diffusers.
      " The thermal criteria could be threatened for reverse flows of duration in excess of two hours, and may require cooling tower operation to prevent exceeding the temperature limits. (Note: this finding is based on the thermal criteria of 1979, which included hourly averaging for the temperature rise.)

14

• The underwater dam does not adversely affect diffuser mixing.
• The underwater dam limits the thickness of stratified layers (thermal wedge) that may propagate upstream for low and reverse flow conditions.
• The experimentally determined entrainment coefficients yield mixed temperatures that are slightly conservative (i.e., lower) than those of the design theory.

Overall, the model study supports the adequacy of the diffuser design for efficiently mixing the thermal effluent in the receiving water. The model study also provided a good basis for defining the mixing zone. Although a large amount of the mixing occurs in the first 500 feet downstream of the diffuser, a length of about 1500 feet is needed, based on the overall design of the SQN heat dissipation system, to provide adequate dilution for the State thermal criteria. Confirmation of the diffuser performance and mixing zone, at least for the type of conditions examined in the model, is found in field studies, discussed in the following. 3.2 Field Studies Field studies of the SQN thermal discharge have been ongoing since the plant began releasing heat to Chickamauga Reservoir. The NPDES permit effective July 1979 stated that the "permittee shall implement a field program to verify model predictions and document the three-dimensional extent and configuration of the thermal plumes in the intake basin, diffuser pond, and Tennessee River. " The permit required studies for both one-unit and two-unit operation and specified that subsequent reports shall be submitted annually, if necessary. Commercial operation of Unit 1 began in early July 1981. Subsequently, on July 24, TVA conducted the first hydrothermal study for the diffuser discharge (TVA, 1982). A summary of river conditions and plant conditions for the test is given in Table 1. The river discharge was about 27,000 cfs with an ambient water temperature of 81. 1F (27.3°C) and about 0.5 FP (0.3 C0 ) of stratification. SQN was operating in open mode, discharging about 1240 cfs through the upstream diffuser at a temperature about 20.9 F0 (11.6 C0 ) above the ambient (5-foot) temperature. The study included measurements of water temperature in and around the diffuser mixing zone, allowing the development of isothermal plots to examine the three-dimensional extent of the thermal plume. Example plots are given in Figure 6. In general, it was found that:

   " The measured dilution of the thermal discharge was greater than that predicted by theory based on physical model tests.
   " Intense initial mixing occurred with the cool bottom water in the immediate vicinity of the diffuser.

• Further mixing occurs at shallower depths, with the thermal plume emerging at the water surface about 660 feet downstream of the diffusers.

15

0 0 Table 1. Field Studies for Sequoyah Nuclear Plant River Conditions (A) Sequoyah Conditions (A) Measured NPDES (A) Thermal Compliance Date Discharge Ambient Stratification (C) Generation ifueDiffuser Operationio Downstream ) Temperature Temp ( Units I Total Mode I Total I Discharge Discharge Temperature (F) Rise (cfs) (F) (FP) MWe Legs ") Discharge (cfs) I Temp('F) I Temp(F)) Rise (0 F) ( (F) Jul 24, 1981 26,700 81.1 0.5 1 1 1100 Open U/S 1 1240 102.0 20.9 84.0 2.9 77 7~7~ 1&~~ '2290 9"pn U/S&DISI'[~~___________ ~ 134 May 14, 1982 8,000 73.7 11.8 1& 2 1460 Open U/S&D/S I 2550 80.5 68 72.6 11 2______ 38X0226 uOpen$:ý _____________ 2O4( 4.1j:2 Nov 10, 1982 35,000 59.0 0.2 1 I 1150 Open U/S I 1287- 93.2 342 60.7 1.7 May 11, 1983 25,000 64.4 3.3 1&2

                                                                    &        2350      Open     U/S&D/SI 2580                88.0            23.6           68.7                4.3 I 20. Oe               I;

UIS&iD1S k!2490 ;*rI*2:*3 2';¢"::??::°*'! ..

I43~000 0.19 j 1~ I 3 -2 ')27~ PUnteady 'Unsteady, Jul 24, 1997 40,000 83.9 3.6 1 & 2 1 2310 Open UIS&D/S 2470 107.3 1 23.4 84.6 0.7 7-- - I -7 24 '2080-Ma2:9&Kb1 i.0pen ..2 29 1 760 1- 24.2. , 5 1U/S&D1S-:

                                                                                                                                                               -8 Aug 2, 2000        9,000         82.1              0.2            1 &2       12300     Helper   U/S&D/S 12480.              100.2      I      18.1          85.7                3.6 17,000 2OO2 J-l27

• 180 17* .- 1-.2> <2290 26 10-

                                                                                                `HelprU/S'&D/S,,         '-993*'         -    15.53-                   !.-{     26 .866 Apr23, 2003(1)     30,000         63.2               1.1             1        1180      Open     U/S&D/S 1    1260      '     88.3            25.1           64.6                1.4 Notes:   (A) Approximate average values throughout duration of field study. Hourly conditions often vary throughout the study depending on the diurnal changes in meteorology, turbulent fluctuations, and perhaps other unsteady undulations in the mean flow.

(B) Ambient water temperature measured at 5-foot depth at Station 13 (SQN intake skimmer wall). (C) Stratification computed as the difference in water temperature between the 5-foot depth and skimmer wall bottom opening. (D) U/S = upstream diffuser leg and D/S = downstream diffuser leg. (E) Diffuser discharge temperature rise computed as the difference between the diffuser discharge water temperature and the ambient water temperature. (F) Downstream temperature as given by the average of field measurements at the 5-foot depth across the downstream edge of mixing zone. (G) Temperature rise computed as the difference between the measured downstream water temperature and the ambient water temperature. (H) Field study of March 1, 1996, conducted with unsteady river flows to evaluate temperature rate-of-change. (I) Field studies of July 27, 2002, and April 23, 2003, included temperature measurements only at the downstream end of mixing zone. 16

0r I 100. t 200 I300 I METERS 0 (a) Water Temperature Distribution at 5-Foot Depth 3E w 10

                .100    0            200             400          600 DISTANCE FROM DIFFUSER, m (b) Water Temperature Distribution along Section B-B Figure 6. Water Temperature Measurements from Field Study of July 24, 1981 (after TVA, 1982) 17

• After breaching the surface, the plume continued to spread, extending over a substantial depth at the downstream end of the mixing zone.

     "   A thermal wedge extended upstream of the diffuser about 300 feet.

• Water temperatures at the boundary of the mixing zone were well within NPDES limits.

As required by the permit, the hydrothermal study also included the diffuser pond, where it was found that the water temperature was fairly uniform and not significantly different from the temperature of that exiting the plant. This is because:

• The pond is small compared to the volume of water passing through the pond.

     "   The turbulence in the flow is strong enough to produce well-mixed conditions with little stratification.

• The surface area of the pond is small, resulting in very little heat loss to the atmosphere.

Because of these properties, it was concluded that the water temperature in the pond during helper mode operation, when the cooling towers are in service, would likely exhibit the same basic characteristics. Hence, no further hydrothermal studies were conducted for the pond. The

• diffuser pond, although part of the treatment system for SQN waste heat, is not naturally connected to Chickamauga Reservoir. As such, beginning with the NPDES permit effective September 1993, the diffuser pond is no longer recognized as waters of the State and is not included as part of the mixing zone.

It should be emphasized that the same is not true of the intake forebay, which consists of an embayment connected to the main channel of the river. As previously indicated, during closed mode operation, the intake forebay is considered part of the mixing zone. SQN has operated in closed mode only once, about ten days in January 1985. This event occurred when severe cold weather entered the Southeast coincident with a period of low river flow. Due to the need for power, it was undesirable to derate the plant. Thus, to prevent violation of the temperature rise criterion, SQN initiated closed mode operation (i.e., at that time the AT limit included a maximum hourly average of 5.4 F/3.0 C' at all times). Due to the unexpected nature of the event and the harsh winter conditions, it was not possible to perform a hydrothermal study of the forebay. It also is worth noting that in this event ice created about $1.2 million in damage to the cooling towers (1985 dollars). With the current thermal criteria and monitoring requirements, SQN should never again need to enter closed mode operation. However, if this were to change, and if sufficient time is available, TVA would perform appropriate studies of the intake forebay to determine the characteristics of the thermal discharge, per the intent of the NPDES permit of 1979, and to monitor indigenous populations of shellfish, fish, and wildlife. Because not all the studies required by the 1979 permit were completed, the NPDES permit

• effective April 1983 again stated that the "permittee shall implement a field program to verify model predictions and document the three-dimensional extent and configuration of the thermal 18
• plumes in the intake basin, diffuser pond, and Tennessee River." In addition, to support the validity of implementing a computed compliance, the 1983 permit also specified "field tests shall be conducted to establish the diffuser performance characteristicsto be used in the numerical model." These requirements were satisfied by six field studies conducted between April 1982 and May 1983 and summarized in a report dated August 1983 (TVA, 1983). The basic conditions of these tests again are given in Table 1. They include springtime studies conducted on April 4, 1982; May 14, 1982; March 31, 1983; and May 11, 1983; and fall studies conducted on September 2, 1982, and November 10, 1982. Depending on the specific study, the river discharge varied between about 8,000 cfs and 35,000 cfs and the ambient water temperature between about 51.5°F and 77.9°F (10.8°C and 25.5°C). In one case, stratification was essentially nonexistent (i.e., study of November 10, 1982) and in another it was as large as 11.8 F° or 6.6 C' (May 14, 1982). SQN operation also varied among the studies, including both one-unit and two-unit operation, open and helper mode operation, and single and dual diffuser leg operation.

The diffuser discharge temperatures varied between 6.8 FP or3.8 C' (May 14, 1982) and 34.2 FP or 19.0 C' (November 10, 1982) above the ambient (5-foot) temperature. The studies included measurements of water temperature at depths of 3 feet, 5 feet, and 7 feet (1.0 meter, 1.5 meters, and 2.0 meters) along several cross sections, including:

• Longitudinal sections along the left and right sides of the mixing zone, and along the centerline of the mixing zone (looking downstream).
• Lateral sections at the downstream end of the mixing zone.

e Lateral sections along three transects within the mixing zone (March 31, 1983, and May 11, 1983, only). The temperatures at the three depths were averaged to produce plots of the temperature at the 5-foot depth. An example for the study of May 11, 1983, is provided in Figure 7. This information, subsequently, was used to examine the three-dimensional extend of the thermal plumes. From the 1982 and 1983 tests it was found that:

• When hydrothermal conditions allow the thermal plumes to reach the surface, it usually does so very close to the diffusers.

     " In some cases, the plumes extend upstream of the diffusers as a thermal wedge, the extent of which depends on the prevailing flow conditions.
     " For studies conducted at higher river flows, 35,000 cfs and above, the thermal plumes are forced downstream (i.e., no thermal wedge extending upstream).

• For conditions with strong stratification, the thermal plumes can be diluted by cool bottom water before reaching the water surface, causing the plumes to remain submerged at depths perhaps greater than the 5-foot compliance depth (May 14, 1982).

19

0 TIME 15 11154 TIM IS 8I40 TIM/E IS 6e 5.

                                                                                                                                                                                                                                                                                                                                                             'K.>

I. ---------

                                                         --                -        -         I     -        I.---                       26.4 2-0                                                                                          aI20.4 6                                                                                                                     II

• s6 1* I - I I 19.8 j I.B 15 8
• iI I £ 2ma 10

_1 -. - - - _- -. . . ..-- t

• I 6* 19.2

                                                                                                                                    <I 13.8 F-19.2 I                 I                                                     I flow                                                                                ,          '             flow 01 13.6 18.6              te     I                                            I
                                                                                        ~

I . . .. . . . . . . . . - .-1. .- .-.. . .. . . . . . . . . . . . . Li 0. Li 0-.

                                                                                                                                                 --.  . -  . . . .                  ----------         . --- . ---- - - .--       - Lj I--

L3 e: 0-Y_ Li 18.0 I I I Ld 18.6 I I 17.4 LONGITUDINAL UPSTR. RUN @ LS OF CHANNEL LONGITUDINAL UPSTR. RUN @ CHANNEL CL LONGITUDINAL UPSTR. RUN 9 RS OF CHANNEL (a) Approx left-hand side of mixing zone (b) Approx centerline of mixing zone (c) Approx right-hand side of mixing zone 21.0 21.0 3k:22.8

                                                                                                                                                     -- - :50 a.*.                                                                                  -       714-9         *.                                --        11:4 0m.
                       -- 9:53                ,*                                                                                                       12-37-- p.-                                                         -                                -5:1                                            - -       11-47        1 . -.-.         -.

21.5 11- - -24 20.5 20.5 a -I . . . ... . . . . . . . . . . . . . . . 0 ...... .: U21.0 20.0 .... . .i I_ A L - - - aL I... ./'" ". i I i i "o 28.8 - - -. -.- . . r - -. . ..- Ir i "- - - - - - - i - -- 128.8 20.5

3 */ , - - , I,

19.

• 7. . . . . -- - - -

C-N II I I I Z0.0 - '",:% -'-. . .. .;-:.-. _L....'.-.a.,_:___...- . <12.5 ... ,1 ..'i,_ _.£!  : I-

                    .. ..    .     . .   .  ~    ..      -°      7            I                 \        -       +     ;                       _--r---- .,               -            ------      -r               " --

_ . _* ,. I LI , /,af / I'; * ,  : L 19.5 13.0

                                     -                 ~i/         /                                            ,I, 10.5                                                                                                                                                                                    -y- r,        *-.-'

18.1 18.5 S is 8 380 86o 200 1200 1500 1800 a 300 888 2900 108 1582 1888 a 386 6se 2e8 120a 1286 1800 DISTANCE FROM LEFT BANK (fee.) DISTANCE FROM LEFT BANK (feet) DISTANCE FROM LEFT BANK (feet) (d) Approx 500 feet downstream of diffusers (e) Approx 1000 feet downstream of diffusers (f) Approx 1500 feet downstream of diffusers (downstream end of mixing zone) Figure 7. Water Temperature Measurements from Field Study of May 11, 1983 (after TVA, 1983; plots a, b, c based on facing northern side of main channel; plots d, e, f based on facing downstream) 20

     "   The thermal plumes are often asymmetric relative to the center of the mixing zone, with cooler water residing on the right side of the plume (facing downstream).
     " The region where the thermal discharge raises the water temperature above ambient extends beyond the NPDES-defined mixing zone, and can be as much as 1500 feet wide at the downstream end of the mixing zone with both diffusers in operation.
     " If the plume is defined by contours depicting the thermal criteria (e.g., for Td, the locations where the downstream temperature is 86.9°F (30.5°C); for AT, the locations where the temperature rise is 5.4 F0 (3.0 C0 )), the plume always remains within the NPDES-defined mixing zone.

Regarding the computed compliance, it was found that the hydrothermal model performed better in reproducing the measured temperature at the downstream end of the mixing zone than that of the Station 8 and Station 11 monitors (e.g., see Figure 1). The average discrepancy of the monitoring stations was about 0.72 F0 (0.40 C0 ), whereas that of the numerical model was only 0.40 P (0.22 C0 ). Based on the results of the field studies summarized above, in March 1984 the State granted approval for SQN to use the numerical model to monitor compliance with the NPDES requirements, provided "TVA verify that the measurement of the temperature of the water at the skimmer wall is not effected by the presence of the underwater dam and that this underwater dam has negligible effect upon the computed compliance model." Later, in June 1984, TVA provided a short report containing measurements from a field test that included water temperature at the skimmer wall and the underwater dam (TVA, 1984). The measurements showed that the skimmer wall and underwater dam temperatures usually agree within 1.8 FP (1 C0 ). The report also pointed out that any impact of the underwater dam would be properly incorporated into the computed compliance because the numerical model is validated based on data from field studies that include the effects of the dam on the mixing of the thermal discharge. The next concern prompting requirements for field studies arose out of a meeting between TVA and the State in November 1986 (TVA, 1986 and TDWPC, 1987). The purpose of the meeting was to discuss reservoir dynamics, hydrothermal processes, power plant operation, and other factors influencing compliance with thermal water quality standards. In the meeting, it was agreed that TVA develop a quality assurance (QA) program consisting of field verification tests to ensure that the plant-induced effects on water temperature were being determined accurately and consistently. In response to this agreement, TVA issued a QA program in September 1987 calling for verification studies to be performed for a variety of river and plant conditions (TVA, 1987). These conditions are summarized in Table 2. Briefly, conditions for river flow QR were divided

• into four ranges: QR<10,000 cfs, 10,000 cfs <QR< 2 5 ,000 cfs, 25,000 cfs <QR< 3 5 ,000 cfs; and QR> 3 5 ,000 cfs. For each range it was desirable to perform a study for each season of 21

the year. The largest release of heat will include SQN operation with two units. The 0 original plan called for a winter study at low flow with one rather than two units, but the recommendation for this case has since shifted to a two-unit study. The QA program also provided a description of the proposed field testing, which included measurements at depths and locations somewhat similar to those of previous studies. In the QA program some of the recommended field studies were already fulfilled by previous tests, as summarized above. Table 2. Field Studies by TVA QA Plan of 1987 Notes A. Field study summarized in report by TVA (1982). B. Field studies summarized in report by TVA (1983). C. Field studies summarized in this report. It is important to note that the NPDES permit effective April 1983 was designated to expire in March 1988. However, in late 1986, both units at Sequoyah were removed from service due to nuclear safety concerns. Unit 2 did not return to service until May 1988 and Unit 1 did not return to service until November 1988. Due to this, and due to ongoing studies and negotiations related to the 316(a) variance request of 1989, the plant continued to operate under the NPDES permit of 1983. The next permit was finally issued in September 1993. The 1993 permit did not reference the TVA QA program of 1987, but did require that "the permittee shall perform instream surveys for the plume volume and area during November to March of 1992-1993 and 1993-1994 when the temperature rise is within the range of 3 C' to 5 C'. " In this statement, the period November to March of 1992-1993 must have been a misprint because it preceded the effective date of the permit (i.e., September 1993). As such, this requirement was interpreted to include November to March of 1993-1994 and 1994-1995. 0 22

In the ensuing periods (i.e., November to March of 1993-1994 and 1994-1995), the river flow and water temperature did not reach conditions suitable for a field study to be performed for a temperature rise in the range of 5.4 FP to 9.0 F0 (3.0 C0 to 5.0 C0 ). Short-term variations in the temperature rise occurred, but did not persist for a period long enough to mobilize equipment and personnel for field measurements. Under these conditions, TVA moved forward to perform field studies as summarized by the QA program summarized in Table 2. Note that this program yet recommends wintertime studies at low river discharge, which produces a large temperature rise of the type stipulated for study in the NPDES permit of September 1993. The field tests conducted during the tenure of the NPDES permit effective September 1993 are given in Table 1. They include spring studies on March 1, 1996, and March 24, 1999, and summer studies on July 24, 1997, and August 2, 2000. The study of March 1, 1996, was conducted in support of the supplemental 316(a) demonstration of 1996. The purpose of the study was to determine the zone of impact for the temperature rate-of-change. To create a rate-of-change event, the river discharge was altered in a short period from a flow of about 43,000 cfs to a flow of 20,000 cfs. The focus of the study was to examine the longitudinal (i.e., downriver) extent of the temperature rise created by the event. In this manner, the study did not include detailed measurements of the three-dimensional configuration of the thermal discharge, but only temperature profiles along the center of the river. The study found that the longitudinal extent of the mixing zone (i.e., 1500 feet) was sufficient for maintaining the wintertime criteria for instream temperature rise (i.e., 9.0 P/5.0 C°). In contrast, the studies of July 24, 1997, March 24, 1999, and August 2, 2000, were designed to evaluate the three-dimensional extent and configuration of the thermal discharge, as specified in the TVA QA program of 1987. Results of these studies are shown in Figure 8 through Figure 11. Each figure contains: (a) a plot of the water temperature distribution at the 5-foot compliance depth, and (b) plots of the water temperature and water temperature rise along transects across the mixing zone at the sections about where the thermal plumes breach the water surface and at the downstream end of the mixing zone, again at the 5-foot depth. It is important to note that these measurements were made by trolling temperature sensors through the water from a boat. The boat tracks are shown in the figures. The temperatures were measured with sensors having an accuracy of about +/-0.25 F0 (+/-0.14 C0 ) and a response time of about 0.7 second. Based on the boat speed and sampling frequency, the sensor readings represent near-instantaneous temperatures taken at intervals roughly every four to six feet along the boat tracks. It is emphasized that although the plots in Figure 8 through Figure 11 were created from instantaneous measurements, they do not represent an instantaneous snapshot of the thermal discharge. Depending on the study, the time required for the boat to traverse the indicated tracks varied between about 65 minutes and 135 minutes. In this manner, due to the time-varying turbulent motions in the flow, the plots represent "blurred" rather than "clear" images of the thermal discharge at the 5-foot depth. If additional data sets were collected, the general location of the thermal discharge would likely remain unchanged. However, the shape of the temperature distributions would 23

shift over distances associated with the size of the dominant turbulent motions in the flow. From a statistical standpoint, the plots represent "probable" rather than "definite" images of the thermal discharge. With this understanding, the following general comments are provided for each field study. 3.2.1 July 24, 1997 Study The study of July 24, 1997 (Figure 8) included a high river discharge, about 40,000 cfs, and a relatively high ambient water temperature, 83.9°F (28.8 0 C). Stratification was moderate, with water at the channel bottom about 3.6 F0 (0.3 C0 ) cooler than the ambient temperature (5-foot depth). SQN was operating in open mode with both units, discharging about 2470 cfs through both diffusers at a temperature of about 23.4 F0 (13.0 C0 ) above the ambient temperature at Station 13. The following features are noted (Figure 8). Even though both diffusers are operating, the thermal discharge seems to breach the 5-foot depth as a single plume in the center of the main channel. It is emphasized that the diffusers are approximately 40 feet below the 5-foot depth. Depending on the magnitude and direction of the mean and turbulent motions in the flow, it is reasonable to expect the plumes at the 5-foot depth to drift from side-to-side in the mixing zone. It seems unlikely, however, that the discharge from each diffuser would coalesce into a single plume. One thought is that perhaps parts of the diffusers were clogged. Such clogging, however, would have produced an unusually high water level in the diffuser pond, which was not observed. Other possible factors include the following:

           " Due to moderate stratification, parts of the thermal effluent are significantly cooled and reach a level of neutral buoyancy below the 5-foot depth. The high river discharge also would promote mixing and "bending" of the thermal discharge, sweeping it downstream before reaching the 5-foot depth. Perhaps the only parts of the plumes containing sufficient buoyancy to reach the water surface were those in the middle of the river, emerging side-by-side in what appears to be a single plume.
         /   Part of the thermal effluent was undetected in the field study due to undulations in the flow and an insufficient number of measurements in the region where the plumes breach the surface. If undulations temporarily submerge the plume below the 5-foot depth, and if they occur at a time-scale longer than that for the survey boat to traverse the breaching area, it is possible for part of the plume to go undetected. The first transect downstream of the diffuser was at about 500 feet. Additional transects may have revealed evidence of two plumes (i.e., one plume for each diffuser).

0 24

    "   Due to high river flow, there is a sharp gradient between the upstream ambient temperature and the plume temperature. There is no thermal wedge propagating upstream in the surface layer of the flow.
    " The mixing zone maintains the thermal discharge below the NPDES thermal criteria (i.e., max Td of 86.9°F/30.5°C and max AT of 5.4 P/3.0 C0 ).
    " North and south of the mixing zone, natural heating creates high temperatures in the overbanks (plot "a" of Figure 8). In some areas, the overbank temperature is higher than that in the mixing zone (yet below the NPDES thermal criteria).

These results emphasize the difficulty of tracking SQN thermal compliance by measurements at the outer edges of the mixing zone, as was done in the early 1980s, and the strength of using a computed compliance, which keeps an accurate accounting of the amount of heat added to the reservoir by the plant. At the section where the plume breaches the water surface (plot "b" of Figure 8), the water temperature is below the ambient temperature for all except the center of the plume (i.e., the local temperature rise is less than zero, except near the center of the plume). This is a consequence of stratification. The ambient water temperature measured at the 5-foot depth at Station 13 is 83.9°F (28.8°C); whereas that near the bottom of the main channel is closer to about 80.0°F (23.7°C). Due to the upward flux of the diffuser discharge and entrainment of ambient flow, the cooler bottom water is forced to the surface, yielding temperatures in parts of the mixing zone that are lower than the ambient temperature measured upstream. 3.2.2 March 24, 1999 Study The study of March 24, 1999 (Figure 9) again included a relatively high river discharge, about 35,000 cfs. As a springtime test, however, the ambient water temperature was cooler, 51.8°F (28.8°C), and contained essentially no stratification. SQN was operating in open mode with both units, discharging about 2490 cfs through both diffusers at a temperature about 24.2 FP (13.4 C0 ) above the ambient temperature at Station 13. The following features are noted (Figure 9).

    "   Two plumes breach the 5-foot depth, one for each diffuser leg.
    "   The peak temperature for the diffuser located in the northern side of the main channel is about 2 F0 (1.1 C0 ) warmer than that located in the southern side of the main channel (i.e., at the 5-foot depth where the plumes breach the water surface).
    "   Due to high river flow, there is a sharp gradient between the upstream ambient temperature and the plume temperatures. There is no thermal wedge propagating upstream in the surface layer of the flow.

25

    " The mixing zone maintains the thermal discharge below the NPDES thermal criteria (i.e., max Td of 86.9°F/30.5°C and max AT of 9.0 P/5.0 C°).
    " For the prevailing river and plant conditions, the thermal plumes appear to spread into the overbank on the north side of the main channel. This is likely a consequence of currents created by river curvature. At high river flow, water moving through the bend in the river upstream of the mixing zone will tend to flow "straight" and impact the southern shoreline opposite the diffusers. That is, at high river flow, water velocities on the outside of the bend will tend to be higher than those on the inside of the bend. Moving downstream from this point, it appears that the alignment of the shoreline (with higher river velocities) will tend to push the thermal plume away from the shoreline towards the northern edge of the mixing zone. For this reason, measurements from Station 8 will likely underestimate the temperature at the downstream end of the mixing zone for high river flow (i.e., supporting the use of the hydrothermal compliance model). Other factors, however, also may be responsible, at least in part, for this behavior, including the following:
        /   Recirculation: A zone of separation created by the shoreline protrusion at the diffusers (see Figure 9) may exist. If it exists, recirculation could entrain thermal effluent from the northern edge of the mixing zone, but at water temperatures below the NPDES criteria. Again, this type of behavior would be significant only at higher river discharges, where there is ample river flow for dilution of the plant thermal effluent.
        /   Wind: Other TVA studies have found that wind can have a significant effect on water motions in the surface layer of the flow (TVA, 1998). During the study of March 24, 1999, a sustained wind was blowing out of the south at about 6 mph, perhaps inducing the plume in the surface layer to spread more northward into the right overbank (i.e., compared to quiescent wind conditions).
        $    Insufficient data: Note that the boat transects are sparse in the downstream half of the mixing zone. It may be that the plumes also exist in this area, but were not measured. Concurrently, unsteady undulations in the flow, as described above, could also add bias to the survey results.

It is interesting to note that even though the study of July 24, 1997, was conducted at high river flow, it did not appear to exhibit spreading towards the northern overbank as in the study of March 24, 1999 (i.e., compare Figure 8 and Figure 9). In reality, such spreading may exist, albeit unnoticeable in the measurements. Also recall that the study of July 24, 1997, contained moderate stratification, which could perhaps disrupt secondary river currents or other spreading processes. 26

3.2.3 August 2, 2000 Study The study of August 2, 2000 included a low river discharge, only about 9,000 cfs, with a relatively high ambient water temperature, 82. I°F (27.8°C). Stratification was essentially nonexistent. SQN was generating with both units, but because of the high ambient temperature and low river flow, the plant was operating in helper mode (i.e., cooling towers in service). Under these conditions, the plant was discharging about 2480 cfs through both diffusers at a temperature of about 18.1 F0 (10.1 C°) above the ambient temperature at Station 13. Two passes were made with the survey boat, an early morning pass (Pass 1-Figure 10) and a late morning pass (Pass 2-Figure 11). The following features are noted.

• Two plumes breach the 5-foot depth, one for each diffuser leg. The plumes emerge within 500 feet of the diffusers and are evenly spaced in the mixing zone.
• For Pass 1, the peak temperature for the diffuser located in the northern side of the main channel is about 1 F0 (0.6 C0 ) cooler than that located in the southern side of the main channel (i.e., at the 5-foot depth where the plumes breach the water surface). Note that this is opposite of that which was observed in the test of March 24, 1999.
• For Pass 2, the peak temperatures at the 5-foot depth, where the plumes breach the water surface, are about 0.4 F0 (0.2 C0 ) cooler than those for Pass 1. The peak temperature for the northern side of the main channel is still about 1 F0 (0.6 C0 )

cooler than that for the southern side of the main channel. Also note that the number of boat transects for Pass 2 are less than that for Pass 1, which somewhat diminishes the confidence in the resolution of the plume shown in Figure 10.

• Due to low river flow, the plume in the surface layer of the flow forms a thermal wedge that propagates upstream of the diffuser.

      " The mixing zone maintains the thermal discharge below the NPDES thermal criteria (i.e., max Td of 86.9°F/30.5°C and max AT of 5.4 F/3.0 C0 ).

• The thermal plumes spread into areas outside of the mixing zone, but at levels below the NPDES thermal criteria.

3.2.4 Studies in 2002 and 2003 Two field studies were performed under the NPDES permit of August 2001-a summer study on July 27, 2002, and a spring study on April 23, 2003. Results from these studies are summarized in Table 1. In contrast to the studies above, these 2002 and 2003 studies included instream measurements only at the downstream end of the mixing zone. The purpose of the studies was to collect information for calibration of the numerical model used for the computed compliance and did not include measurements to assess the 0 ambient river temperature or the three-dimensional extent of the thermal plume from the discharge diffusers. 27

S (a) Water Temperature Distribution at 5-Foot Depth 88 87 86

• 85 E 84 I--

83 82 4 3 f--

  .*   2 U,
   -   1
      -0 E
     -2 0 50   100  150    200    250     300    350     400    450      500    550   600 650 700 750 Distance From Left Side Of Mixing Zone (feet, facing downstream)

(b) Water Temperatures Across Mixing Zone at 5-Foot Depth Figure 8. Water Temperatures from July 24, 1997 Study 28

(a) Water Temperature Distribution at 5-Foot Depth 57 56

 - 55

- 54 CL E 53 I-- 52 51 5-4 U- a, 3 2 2 i 1 0. E I 0

    -1 0 50    100  150    200    250    300    350     400    450      500   550    600 650 700 750 Distance From Left Side Of Mixing Zone (feet, facing downstream)

(b) Water Temperatures Across Mixing Zone at 5-Foot Depth Figure 9. Water Temperatures from March 24, 1999 Study 29

(a) Water Temperature Distribution at 5-Foot Depth 89 88 o 87

• 86 E 85 a)

I-84 83 7 6 a)5 24 D 3 E 1-2 0 50 100 150 200 250 300 350 400 450 500 550 600 650 700 750 Distance From Left Side Of Mixing Zone (feet, facing downstream) (b) Water Temperatures Across Mixing Zone at 5-Foot Depth 0 Figure 10. Water Temperatures from August 2, 2000 Study, Pass 1 30

(a) Water Temperature Distribution at 5-Foot Depth 89 88 87 0-E 85 I-- 84 83 7-6- U-

  . 5 T    4
  ýi3 CL E

2 0 50 100 150 200 250 300 350 400 450 500 550 600 650 700 750 Distance From Left Side Of Mixing Zone (feet, facing downstream) (b) Water Temperatures Across Mixing Zone at 5-Foot Depth 0 Figure 11. Water Temperatures from August 2, 2000 Study, Pass 2 31}}