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{{#Wiki_filter:ENCLOSURE 1 | {{#Wiki_filter:ENCLOSURE 1 | ||
PROPOSED CHANGES TO UNIT 1 TECHNICAL SPECIFICATIONS APPENDIX A | PROPOSED CHANGES TO UNIT 1 TECHNICAL SPECIFICATIONS APPENDIX A | ||
t SAFETf L.l LMIT Fuel Claddin Inta rit LIHITINC SAPETT 2.1 Fuel Claddin I | |||
SYSTRH SETTING Inta rit Core eptay and U'CI > 378 in. | |||
actuation | |||
~ | |||
teactot above vebbe lou uatet level sero J. HPCI end RCIC > 470 iri. | |||
ac'tuation reactor above vebbe'I Icnr water level sero Ko H4fn bteaQL isola > 470 in. | |||
tion valve cloeure above veebel reactor lou vater sero level | |||
TABLE a+1~B REACTOR PROTECTION SYSTEM (SCRAM) INSTRUMENT CALIBRATION MINDCUM CALIBRATION FREQUENCIES FOR REACTOR PROTECTION INSTRUMENT CHANNELS Instrument Channel Group (1) Calibration Minimum Frequency (2) | |||
IRM High Flax Cccaparison to APRM on Control- Bate (4) led Shutdowns (6) | |||
APRM High Flux Output Signal ~ B Heat Balance Once every 7 days Flew Bias signal B Calibrate Floe Bias Signal (7) Once/operating cycle B TIP System Traverse (8) Every 1000 Effective Full Pcerer Hours High Reactor Pressure Standard Pressure Source Prexy 3 Months High Dryvell Pressure Standard Pressure Source Every 3 Months Pressure Standard Evezy 3 Months | |||
. High Rater Level in Scram Discharge Volame h Note (5) Note (5) | |||
Turbine Ccadeaser Lcm Vacuum h standard Vacuum Source 5 | |||
Every 3 Months I | |||
Main Steam Line Imlation Valve Closure h Note (5) R)te (5) | |||
)Cain Steam Liae High Radiatioa B Standard Cuxrent Source (3) Every 3 Months Turbine First stage. Pzessare permissive h Standard Pressure Source Every 6 Months Turbiae contxol valve - Loss of oil pressure h Standard Pressure Source ChaceIoperating cycle Tarhine Stop Valve Closure Note (5) Note (5) | |||
4 | NOTES FOR TABLE 4'.l.B 1, A description of three groups is included in the bases of this specif ication. | ||
to | : 2. Calibrations are noc rcquiied when the systems aze not required to be operable or are tripped. If calibracions arc missed> they shall be performed prior co returning the syste'm to an operable status. | ||
The | : 3. The current source provides an instrument channel alignment. Cali-bration using a radiation source shall be made each refueling outage. | ||
The | 4~ Haximum frequency required is once per week. | ||
The | Physical inspection and actuation of these position, svitches vill be performed once per operating cycle. | ||
6, On controlled shutdowns> overlap between the IRM's and APRM's will be verified. | |||
: 7. The Flow Bias Signal Calibration will consist of calibrating the sensors, flow convcrters, and signal offset necwotks during each operating cycle. The instrumentation is an analog type with redun-dant flov signals that can be compared. The flow compazacoz trip and upscale will be functionally tested according to Table 4,2.C to ensuze the proper operating during the operating cycle. Refer to C'.1 Bases for further explanation of calibration frequency. | |||
: 8. A complete tip system traverse calibrates the LPRH signals to the process computer. Tke individual LPRN meter readings vill be adjusted as a minimum at the beginning of each operating cvcle before reaching 100% pover. | |||
The frequriicy of r.il ilirntion of tli< /'<pgN F1<iv Bfn <inx .'l< twnrh ha<i been i <<t<<hi I </lii'<l a!i i ach rcf<<i. if<<<; ui<r.<g<;. Tlii.r<. <<t>>:;. v< i:il I<<<.t rumenc'< | |||
whfch must be col fbrat>>d anil fr wf ll take aevi ral hn<<r<< to perform the calibration of ch>> enr.fre network. Whfle the calfbratfon is being per-formed, a acro flow signal will bi-. sent ro half o! the 'O'g'l's resulting in a half scram <ind rod block condf.r,ion. Thus, if the calibration were perforned during operation, flux shaping would not be possible. 'Based on experience ac other gcncracing scatfons, drift of instruments, such as those fn ci<c Flow Biasing Hecwork, fr not sfgiiiEicant and therefore, to avoid spurfous scrams, s calibr ~ tfon frequency of each refueling out-age is es ablfshcd. | |||
Croup (C) devices arc 'act fve,only durfr<g a gfven port fon oE che opera-tional cycle. For example, chc It:.'! is active during certup and inactive | |||
~ | |||
during full-power oper-cfon. Thus, chc only tcsc char. fa aeanfngful thc one performed gust prior ro shutdown or startup', i.c., the tests that are perforned gust prior to use of the instrument. | |||
Calfbracfnn frvq<<>>ncy of thc in<icrumcnt chnnicl i~ divided into two groups. These are as folio~a: | |||
: l. F ssive type indfcatfng devfces chat can be co~pared with like units on a continuous basis. | |||
: 2. Vacuum tube or semiconductor devices an<I detectors that drift or lose sensitivity. | |||
Experience with passfv= type fnstruoencs in generating stations and nub-statfons indicates that the specified calfbracfons are adequate. For those devices which criploy amplifiers, etc., drift speciEications call for drift to be less than 0.4X/month; i,c,, in che period of a month a difft of .4V. would occur acd thus providing Eor ad>>quat>> aargfa. Vor the Apg'f system drf ft of clcctronic apparatus fs not:he only considera-tion fn determining a calibration frequency. Ch.ngu .n power distribu-tion and loss of chac<ber sensftivity dictate a calibration every seven days. Calfbrar ion on this frequency assures plant operation at or below thermal if~its.' | |||
coaparfson of Tables'4.1.A and 4.1.6 indicates that two instr~ant channels have not been included fn thc latter cable. These are: code switch in shutdow<i and cianual scram. All of the devices or sensors associated wfch these scram functions arc sf ~pie on-off switches and. | |||
hence,,calfbratfon during operation fs noc sppl'cable, f.e., the swfcch f,'s either on or off. | |||
The ratio of Core Maximum Fraction of Limiting Power Density (MFLPD) to Fraction of Rated Power (FRP) shall be checked out once per day to determine if the.APRM scram requires ad)ustment. This will normally be done by checking the APED readings. Only a small number of control rods are moved daily 47 | |||
Thus, | |||
Experience with | |||
~ | ~ ~ ~ | ||
4~1 BASF.S during steady-state,opera'tion"and thus the .ratio is not expected to change significantly. | |||
The sensitivity of LPRM detectors decreases with exposure to'eutron flux at a slow and approximately constant rate. The APR'I system, which uses the LPRM readings to detect a change in thermal power, will be calibrated every seven'days using a heat balance to compensate for this change in sensi:tivity. The RBM system uses the LPRM reading to detect a localized change in thermal power. It applies a correction factor based on the APRM output signal to determine the percent thermal gower and therefore any change in LPRM sensitivity is comoensated for'y the APRM calibration. The technical specification limits of CHFLPD, CPF., | |||
MAPLIIGR and R ratio are determined by the use of the orocess computer or other backup methods. These methods use LPR'.! readings and TIP data to determine the power distribution. | |||
Compensation in the process computer for changes in LPRH sensitivity will be made by performing a full core Tip traverse to uodate the computer'alculated LPRH correction f"ctors every 1000 effective full | |||
' power hours. | |||
As a minimum the individual LPRH meter readings will be adjusted at the beginning of each operating cycle prior to reaching 100 percent oower. | |||
' | |||
~ | '[nti CAiMO LT KOi<S FOR OPEPuXT iO,'4 .SURVRiLLAhCF. RE UIRQK!iTS 3 3 K Control Rods 4 3 8 l'oncrol Rods 4, Control rods shall noc be Mhen required, Cha presence withdrawn for starcup or of ~ second 1iceasel refueling unless ac least operates'o verify the followiag ot cuo.source range channels the correct rod prograa shally have an observed count race be verified equal to or greater chan | ||
The | ~ | ||
thrae counts per second'. 4. Prior co control rod vithdraMal for acarcup or during refueling, 5..During opcracion Mich verify chac at lease tMo source 1 i<<icing cont ra 1 rod pa c- 'ange channels have ao observed. | |||
carns, as dccermined by the counc race of at least three designated qualified person- counts per second. C nel, either: | |||
: a. Noth R8H channels shall 5. Mhen a limiting control rod be operable: pattern exists, an insceceant or functional test of the RN shall be performed prior to b~ Control rod vichdraMal vichdraval of the designated shall be blocked. rod(s) and at least, once per 24 hours thereafter. | |||
C. Scram Insertion Times 1.After each -refueling outage all operable rods shall be scram time~ | |||
tested from the fully vithdrawn position vith the nuclear system pressure above 800 psig This Insertion Times testing shall be co<<pleted prior to C. Scram exceeding 40X pover. Belov 20X l, The average scram insertion pover, only. rods in those sequences Cine, baaed on the deenergi- (A12 and A34 .or B12 and B ) vhich zacion of the scran pilot valve vere fully withdrawn in th$ region aolenoids as tire zero, of all from 100X rod density to 50X rod operable control rods in the density shall be scram time tested. | |||
reactor power opera c ion condi The sequence restraints imposed upon Cion shall bc no greater than: the control rods in the 100-50 percent rod density groups to the X Xnsortad Froo Avg. Scram Inser- preset pover level may be removed Full Mithdrcun tion Tines sec by use of the individual bypass switches associated vith those . | |||
5 0.375 control rods vhich are fully or 20 0,90 partially vithdravn and are not 50 2.0 vithin the 100-50 percent rod density 90 3. 500 groups. In order to bypass a rod, the actual rod axial position must be knovn; and the rod <<ust be in the correct in-sequence position. | |||
124 | |||
a' Whsga~ | |||
'a 0 | |||
Unit 1 l,wIviir. Cn~nivlnns Fnli sprat TIOU SURVFII.LaÃCF RE~UIM ~FMTS 3.7.C Secondary Containment 4.I.c Secondar Containment | |||
: 1. Sc condnry containment intc; .1 ~ | |||
I Secondary containment surveil-durity shall be maintained in lance shall be perfoaaed as the reactor aonc" at all times indicated helot: | |||
except as apccf(iud in 3.7.C.2. | |||
240 | |||
lP t | |||
%14t 'I 0 | |||
4 ~ 7.C Seconisr I Containment | |||
: a. Secondary containment capa-bility tomaintaim 1/4 inch o vater vacuum under calm Mtn' | |||
+ 5 mph) conditions Mith s system inleafcage tate o f not more than 12,000 cfm, shall be demonstrated at each refueling outage prior to refueling. | |||
: 2. If reactor zone secondary con-1 | |||
: 2. After a secondary containment tainment integrity cannot be violation is determined the maintained the folloving con- standby gas treatment system ditions shall be met: vill be operated inanedisteiy after the affected zones are isolated from the remainder of | |||
: a. The reactor shall bc made the secondary containment to aubcrit ical and Specif ica- confirm its abil'y to main<< | |||
tion 3.3,A shall be mer.. tain the remainder of the secondary containment at 1/4- | |||
: b. The reactor shall be cooled inch of Mater negative prcssure dovn beloM 212'F and the under calm Mind conditions. | |||
reactor coolant system vented. | |||
c; Fuel movemcnt shall not bc permitted in the reac-tor zone. | |||
: d. Primary containment 'ntegri:y ma inta i ned . | |||
3, Secondary containment integrity shall be mslntnlned in the re-fueling zone, except as speci-fied in 3.).C.4. | |||
24) | |||
0 PROPOSED CHANGE TO UNIT' TECHNICAL SPECIPICATIONS APPENDIX B | |||
Monitoring vill be perfors:e6 usinu standard accepted scnpling procc."urea vhich arc on fil'e in the office of'he Division of Forestry, Fisherics, and Hildlife Development, Norris, Tennessee. | |||
Re ortins Recuirencnt The results vill be smaaarized annually in the annual reports of the nonradiological environnental monitoring program. | |||
Baaas proportion of the river flow vill be routed through the plant f'rsignificant A | |||
cooling purposes, and during periods when larval fish ar'e abundan | |||
'for there is the potcrtial entraicuaent of large numbers of fisbes. | |||
The specified study will deteraine the numbers of fish crgs and larva entrained in the cooler"., vater system resulting frow pl.nt operation and identify the need for possible corrective action. | |||
(f) Fish inoin enent on Intake Screens (Delete) was f | |||
\ | |||
s", | |||
\ | |||
PROPOSED CHANGES TO UNIT 2 TECHNICAL SPECIFICATIONS | |||
SAFETY LIHIT LIHITINC SAFETY SYSTEH SEITING A.l" tuel Claddin Int>> rit 2il Fuel Claddin Inta rit I ~ Core epray and LFCI ~ 378 in. | |||
actuation reactor above vestee lou water level cero J. HPCI and RCIC ~ 470 in. | |||
actuation reactor above vesset le vater level cero K. Main ateam ieola<<> 470 in. | |||
tion valve cloeure above veeeef reactor lou eater cero level | |||
TABLE 4alaB REACTOR PROTECTION SYSTEN (SCRAN) INSTRUNKNT CALIBRATION NININUN CALIBRATION FREQQE!CIES FOR REACTOR PROTECTION INSTRUNZNT CHANNELS Instruaent Channel Group (I) Calibration Nininum Frequency (2) | |||
IRN High Flux Caaparison to APRN on Control- Note (4) led Shutdowns (6) | |||
APRN High Flux Output Signal ~ B Heat Balance Oace every 7 days Flow Bias Signal B Calibrate Flow Bias Signal (7) Once/operating cycle LPRN Signal TIP System Traverse (8) Every 1000 Effective Full Power Hours High Reactor Pzessure Standard Pressure Source Every 3 Nonths High Drywall Pressure Standard Pressure Source Every 3 Nonths Reactor Low Mater Level Pressure Standard Every 3 Nonths High heater Level in Scraa Discharge Volam Hots (5) Note (5) | |||
Tarbine Ccadeaser Low Vacuua Standard Vacuua Source Every 3 Ncaths I | |||
Naia Steaa Line Isolation Valve Closure Note (5) Note (5) | |||
Naia Stean Line High Radiati.oa Standard Current Source (3) Every 3 Noaths Turbine First Stage Pressure | |||
. Pernissive Standard Pressure Source Evezy 5 Ncaths Turhiae Coatrol Valve - Loss of Oil Pressure A Standard Pressure Source Csee/operating cycle Turbine stop valve closure Note (5) Note (5) | |||
NOTFS FOR TABLE 4.1.1 A description of three groups's included in the bases of this speciEication. | |||
: 2. Calibrations are not required when the systems are not required to be operable or are tripped. If calibrations arc missed, they shall be performed prior to returning the system to an operable status. | |||
3, The current source provides an instrument channel alignment. Cali-bration using a radiation source shall be made each refueling outage. | |||
4~ Haximum frequency required is once per week. | |||
Physical inspection and actuation of these poiition switches vill be performed once per operating cycle. | |||
5~ On controlled shutdowns> overlap between the IRM's and APRH's will be verified. | |||
: 7. The Flov Bias Signal Calibration vill consist of calibrating the sensors, flow convcrters, and signal offset networks during each operating cycle. The instrumentation is an analog type vith redun-dant flov signals that can be compared. The flow comparato" trip and upscale vill be functionally tasted according to Table 4,2,C to ensure the proper operating during the operating cycle. ReEer'o 4'.1 Bases for Eurther explanation of calibration frequency. | |||
: 8. ' | |||
complete tip system traverse calibrates the LPRH signals to the | |||
~ | |||
process computer. The individual LPRN meter readincs vill be ad)usted as a minimum at the beginning of each operating cvcle before reaching 100% power. | |||
'.t<<tMork ha>> been Th<< freque>>cy o5 r.>11hrnt ion of t'l>> Assed Fl<>M Bin >lax | |||
<<!> <<<<ch refuel in;; uut <<g<<. There <<rc <<.~v> r!>1 1n<<trumrnts a at<<hit<<had Mhich must be ca11hrat<<d and it M111 takr. acv<<r<<1 hnur<< to perform the is being per-calibration of the entire nctuoA. While the calibration formed, a aero EloM signal will b<<sent to half of the >'ZRH's resulting in s half scram and rod block condition. Th>>s, if the calibration Mere performed during operation, flux shaping uould not be possible. Based on cxper'fence at other generating stations, drift oE in truments, such aa those in the Flov Biasing Hetuork, ir not significant and therefore, to avoid spurio>>s scrams, a cal.ibr tion frequency of each refueling out-age is establ ishcd. | |||
Croup (C) devices are active only durin" a given portion oE the opera-tional cycle. For example, the 1g.'! is active during startup and inactive during full-pover oper" tion. Thus> thc only test that is meaningful thc one performed gust prior to ehutdoun or startup, 'i.c., the tests that are performed gust prior to use of the instrument. | |||
Calibrntion frequency of thc in<<trumcnt chan >cl 1e divided into tvo groups. These are as folloMe: | |||
: 1. P ssive type indicating devices that can be comp-red vith like units on a continuous basis. | |||
However, neither the total number impinged nor the proportion of standing stock impinged is expected to adversely affect this population. | : 2. Vacuum tube or semiconductor devices and detectors that drift oz lose sensitivity. | ||
The decreasing trend in green sunfish standing stocks was continuous from 1969 through 1976.Additionally, the increased standing stock in 1977 indicates that the impingement has not adversely affected this population. | Experience vith passiv" type instruments in generating stations and oub-stations indicates that the specified calibrations are adequate. For those devices which employ amplifiers, etc., drift specifications call for driEt to be less than 0.4X/month; i.e., in the period of a month a d> ift of . 47 Mould occur acd thus providing for adequate margin. Por the APR.'1 system d. 1Et of electronic apparatus i<<not:he only considera-tion in determining a calibration frequency, Change in power distribu-tion and loss of chamber sensitivity dictate a calibration every seven days. Calibration on this frequency assures plant operation at or belov thermal limits. | ||
A comparison of Tables 4.1.A and 4.1.B indicates that two instrument channels have not been included in thc latter table. These are: mode sMitch in shutdown> and manual scram. All of the devices or sensors associated vi th these scram funct ions are s imp le on-o. f svitches and, hence, calibration during operation is not sppl'cable, i.e., the switch ie either on or off. | |||
The ratio of Core Maximum Fraction of Limiting Pover Density (MFLPD) to Fraction of Rated Power (FRP) shall be checked out once per day to determine if'he APRM scram requires adJustment. This will normally be done by checking the APRM readings. Only a small number of control rods are moved daily 47 | |||
4~1 BASFS durYng steady-state operation and thus the ratio is not expected:. to change significantly. | |||
The sensitivity of LPRM detectors decreases with exposure to neutron flux at a slow and approximately constant rate. The APR'I system, which uses the LPBM readings to detect a change in thermal vower, will be calibrated every seven days using a heat balance to compensate For this change in sensitivity. The RBM system uses the LPRM reading to detect a localized change in thermal power. It applies a correction factor based on the APRM output signal to determine the percent thermal oower and therefore any change in LPWI sensitivity is comoensated for by the APRH calibration. The technical specification limits of CHFLPD, CPF., | |||
MAPLIIGR and R ratio are determined by the use of the orocess computer or other backup methods. These methods use LPR.'! readings and TIP data to determine the power distribution. | |||
Compensation in the process computer for changes in LPRM sensitivity will be made by performing a full core Tip traverse to uodate the computer'alculated LPRM correction f-ctors every 1000 effective full power. hours. | |||
As a minimum the individual LPRM meter readings will be ad)usted at the beginning of each operating cycle prior to reaching 100 percent power. | |||
L IInc covnLYKovs Foa opERXTtov SURVr.lLLANCF. RE UIRKY. 'HIS 4.3.8 Contxol Rods 4~ Control rods shall noc be vithdraMn for ecarcup or When required, the preaaaca refueling'nless at least of ~ ascoad 1icaaaad operator cMo.source range channels to verify ths followtog ot have an observed count the correct rod program shalL to or grcacer chan rate,'qual be verified. | |||
~ | |||
three counts pcr accond'. 4. Prior co control rod withdravsl for scaxcup or during refueling, 5.,During. operation Mich verify thac ac lease tvo source lcaxns, imi ting control rod pa c-ns determined by che | |||
'ange channels have ao observed count rate of ac least three designated qualif icd persou- counts per second. | |||
nel, either: | |||
a, Both RBtl channila shall 5. When a limiting control rod ba. opcrablc: pattern exists, an lnstrLxssat | |||
'or functional teat of the lQA shall be pcrfoamcd prior to b Control rod wichdraval withdrawal of the designated shall be blocked. rod(s) and ac least once per 24 hours chereaftar. | |||
C. Scram Insertion Times 1.After each refueling outage all operable,,rods shall be scram time tested from the fully withdrawn position with the nuclear system pressure above gOO psig This C. Scram Insertion Times testing shall be completed prior to exceeding 40X power. Below 20X power', only. rods in those sequences | |||
: l. The average scraDI inecL'cion (A12 and A34 .or B12 and B ) which Cima, baaed on the dccnergl-zacion of the scram pilot valve were fully withdrawn in tlat region colcnotds as time zero, of all from 100X rod density to 50X rod operable control rods in che density shall be scram time tested. | |||
reactor power oparacion condi The sequence restraints imposed 'upon tion shall be no greater chan: the control rods, in the 100-50 percent rod density groups to the X Inserted Prom Avg. Scram Inser- preset power level may be removed Full With raMn by uee of the individual bypass switches associated with those 5 0.375 control rods which are fully or 20 0.90 pnrtially withdrawn and are not 50 2.0 within the 100-50 percent rod density 90 3. 500 groups. In order to bypass a rod, the actual rod axial position must bi known,'nd the rod aust be in the correct in-sequence position. | |||
124 | |||
7 Al 1~~4@ | |||
Wi' | |||
Unit 2 | |||
>.shnrif: Cn~nlvin.iS Fnii nrrar71OU SURVF1LLhÃCF RK'iIU1v ~FNTS 3.7,C Secondary Containment | |||
: l. Sc condnry containment inte- 1. Secondary containment surveil-grity shall bc maintained ln lance shall be performed as the reactor tone at all times indicated helot: | |||
except as ~pcclfled ln 3.7.C.2. | |||
240 | |||
3oloC | |||
~ ~ Secondar Containment 4.7.C Scconiar i Containment | |||
: a. Secondary containment capa-bility tomaintafa 1/0 inch o vater vacuum under cain uin" | |||
(< 5 mph) condition uitlt a system inleakage rate oi not more than 12,PPP cf>, | |||
shall bc demonstrated at each reive Ling outage pr io r to refueling. | |||
: 2. If reactor zone secondary con<< 2~ AEter a secondary containment tainment integrity cannot be violation is determined thc maintained the folloving con- standby gas treatmenr. system ditions shall be met: vill be operated innediately after the affected zones are isolated from the remainder of | |||
: a. The reactor shall be made the secondary contai'nment to subcritical and Specifica- confirm its ability to ma in-tion 3. 3. A shall be me t . tain the remainder of the secondary containment at 1/4- | |||
: b. The reactor shall be cooled inch of uatcr negative prcssure doun belou 212'F and the under calm vind conditions. | |||
reactor coolant system vented. | |||
c; Foci movemcnt shall not be permitted in the reac-tor xone. | |||
d." primary containment integri:y maintained. | |||
Secondary containment integrity shall be ma)ntnlneJ in the re-fueling zone, except as'peci-fied in 3.7.'C.4. | |||
241 | |||
PROPOSED CHANGE TO UNIT 2 TECHNICAL SPECIFICATIONS APPENDIX B | |||
0 Honitoring vill be perfonre6 usinu standard accepted scnpling procc".urea | |||
,vhich arc on file in the office of the Divi ion o. Forestry, Fisheries, and Mildlife Development, Norris, Tennessee, Re ortinr Recuirencnt The results vill be su~arized annually'n the annual reports of the nonradiological environmental monitoring program. | |||
Ba"ea A significant proportion of the river flov vill be routed through the plant for cooling pu~nscs, end during periods vh n la> val fish axe abundant there is the potential 'for entrairmcnt of large numbers of fisbes. | |||
The specified stuQ'ill detercLine the nv~bers of fish cr,.".s and lerva entrained in the cool>v", vater system resulting frow pl.at operation and identig the need for po" sible corrective action. | |||
(f) Fish i@pin enent on Intake Screens (Delete) | |||
PROPOSED CHANGES 'TO UNIT 3 TECHNICAL SPECIFICATIONS | |||
SAFETY L IllIT LIMITING SAFETY SYSTEM SETTING 1.1 .FUEL CLADDING INTEGRITY 2 1 FUEL Cl ADDTNG INTEGRITY D. Shutdown Condition C. scram and isola- 2 538 in tion reactor above Whenever the reactor is in low water vessel the shut'down condition level zero | |||
, with irradia ted fuel in the reactor vessel, the D. Scram--turbine 10 per-water level shall not be stop valve cent valve less than 17.7 in. above closure closure the top of the normal active fuel zone. E. Scram- - turbine control valve Fa st closure--Upon trip of the fast acting solenoid valves 2~ Loss of con- 550 psif trol oil | |||
'p.".es sure Scram--low con>> I 23 inches denser vacuum Hg vacuUAl G. Scram--main S 10 per-steam line cent valve isolation closure H. Main steam isola- < 825 psig tion valve closure | |||
--nuclear system ) | |||
low pressure Core spray and h 378 in. | |||
LPCI actuation-- above | |||
'reactor low water vessel l.evel zero HPCI and RCIC 070 in. | |||
actuation--reac- above tor low water vessel level zexo K. Hain steam isola- 070 in. | |||
tion valve above closure--reactor vessel low water level zero ~ | |||
13 | |||
TABLE 4+1 ~ B REACTOR PROTECTION SYSTEM (SCRAN) INSTROHENT CALIBRATION HIHIKOH CALIBRATIOH PREQUE1CIES FOR REACTOR PROTECTION INSTRUMENT CHANNELS Instrument Channel Group (1) Calibration Hinimum Frequency (2) | |||
IRK High Flux Caaparison to APRlC on Control- Note (4) led Shutdcwns (6) | |||
APRH High Flux Output Signal ~ B Heat Balance Once every 7 days Flar Bias Signal B Calibrate Flnr Bias Signal (7) Once/operating cycle LPRH Signal ~ | |||
B TIP System Traverse (8) Every 1000 Effective Full Poser Hours High Reactor Pressure Standard Pressure Source Srery 3 Honths High Drywall Pressure Standard Pressure Source Ee'ezy 3 Honths Reactor tuw Hater Level Pressure Standard Evezy 3 Honths High Hater Level in Sczam Discharge Vol~ Note (5) ~e (5) | |||
~ Turbine Condenser Lov Vacuum Standard Vacuum Source Every 3 lamths I | |||
Hain Steam Line Isolation Valve Closure Note (5) Mte (5} | |||
Hain Steam Line High Radiation B Standard Current Source (3) Every 3 Nouths Turbine First Stage Pressure Permissive h Standard Pressure Source Every 6 Honths Turbine Control Valve - Loss of Oil pressure h Standard Pressure Source &ace/operating cycle Hots (5) Note (5) | |||
NOTf S FOR TABLE 4 . 1. 8 lo A description of three groups is included in the bases of this specif ication. | |||
: 2. Calibrations arc not required when the systems azc not required to be operable or are tripped. If calibrations arc missed, they shall be performed prior to returning the system to an operable status. | |||
3, The current source provides an instrument channel alignment. Cali-bration using a radiation source shall be made each refueling outage. | |||
4~ Haximum frequency required is once per Meek. | |||
: 5. Physical inspecfion and actuation of these position switches will be performed once per operating cycle. | |||
6~ On controlled shutdowns > overlap between the IRM' and APRM' wil1 be verified. | |||
: 7. The Flow Bias Signal Calibration will consist of calibrating the sensors, flow convcrters, and signal offset networks during each operating cycle. The instrumentation is an analog type with redun-dant flow signals that can be compared. The flow comparator trip and upscale will be functionally tested according to Table 4.2..C to ensure the proper operating during the operating cycle . Refer to C'.1 Bases for further 'explanation of calibration~ frequency. | |||
: 8. A complete tip system traverse calibrates the LPRH signals to the process computer. The individual LPRM meter readines will be adjusted as a minimum at the beginning of each operating cvcle before reaching 100K power. | |||
$0 | |||
The frequency of calibration of the APRN Flow Biasing Network has been established as each refueling outage. There are several i,nstruments which must be calibrated and it will take several hours to perform the calibration of the entire netw'ork. awhile the calihration is beinq performed, a zero flow signal will be sent to half of the APRH's resultinq in a half scram and rod block condition. Thu's, if the calibration were performed during operati'on, flux shaping would not be possible. Based on experience at other qenerating stations, drift of instruments, such as those in the Flow Biasing Network, is not significant and therefore, to avoid spurious scrams a cal'ibration frequency of each refueling outage is established. | |||
Group (C) devices are active only during a given portion of the operational cycle. For example, the IRM is active during startup and inactive during full-power operation. Thus, the only test that is meaningful is the one performed gust prior to shutdown or startup; i.e., the tests that are performed gust prior to use of the instrument. | |||
Calibration frequency of the instrument channel is divided into two groups. These are as followss | |||
: 1. Passive type indicating devices that can be compared with | |||
'like units on a continuous basis. | |||
2~ vacuum tube or semiconductor devices and detectors that drift or lose sensitivity. | |||
Experience with passive type instruments in generating stations and substations indicates that thespecified calibrations are adequate. For those devices which employ amplifiers, etc. ~ drift specifications call for drift to be less than 0.4%/month; i.e., | |||
in the period of a month a drift of .4% would occur and thus providing for adequate margin. For the APRM system drift of electronic apparatus is not the only consideration in determining a calibration frequency. Change in power distribution.and loss of chamber sensitivity dictate a calibration every seven days. | |||
Calibration on this frequency assures plant operation at or below thermal limits. | |||
A comparison of Table 4.1.A and 4.1 B indicates that two | |||
~ | |||
instrument channels have not been included in the latter table. | |||
These are: mode switch in shutdown and manual scram. A11 of the devices or sensors associated with these scram functions are simple on-off switches and, hence, calibration during operation is not applicable, i.e., the switch is either on or off. | |||
The ratio of Core Maximum Fraction of Limiting Power Density (CMFLPD) to Fraction of Bated Po~er (FRP) shall be'checked out once per day to determine if the APRM scram requires ad)ustment. his will normally be done by checking the APRH readings. | |||
Only a small number of control rods are moved daily during steady>>state operation and thus the ratio is not expected to change signi.icantly, 46 | |||
'r The sensitivity of LPBM detectors decreases with exposure to neutron flux at a slow and approximately constant rate. The APRM system, which uses the LPRM readings to detect a change in thermal power, will be calibrated eVery seven days using a heat balance to compensate'for this | |||
'change in sensitivity. The RBM'system uses the LPRM reading to detect a localized change in thermal power. It applies a correction factor based on the APRM output signal to determine the percent thermal oower and therefore any change in LPRM sensitivity is compensated for by the APRM calibration. The technical specification limits of CNFLPD, CPF., | |||
MAPLIIGR and R ratio are determined by the use of the process computer or other backup methods. These methods use LPR"! readings and TIP data to determine the power distribution. | |||
Compensation in the process computer for changes in LPRM sensitivity will be made by performing a full core'Tip traverse to uodate the computer'alculated LPRM correction factors every lOW effective full power h'ours. | |||
As a minimum the individual LPRM meter readings will be ad]usted at the beginning of each operating cycle prior to reaching 100 percent power. | |||
\ | |||
LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS 3~ 3 CTIVITY CONTROL I ~ 3 REACTIVITY CONTROL C. Scram Insertion Times C. Scram Insertion Times | |||
: 1. The average scram l. After each refueling outage all insertion time, based operable rods shall be scram time on the deenergization tested from the fully withdrawn of the scram pilot inoperable position with the nuclear system valve solenoids,as pressure above 800 psig time zero, of all control rods This in the reactor power testing shall be completed prior operation condition to exceeding 40$ power. Below shall be no greater 20$ power, only rods in those A than: ~ | |||
sequences (A12 and A34 or B12 and B34) which were fully with- | |||
% Inserted From Avg. Scram Inser- drawn in the region from 100$ | |||
rod density to 504 rod density shall be scram time tested. The 5 0. 375 sequence restraints imposed 20 0. 90 upon the control rods in the 50 2~0 100-50 percent rod density groups 90 3 ' to the preset power level may | |||
: 2. The average of the be removed by use of the indi-scram insertion times vidual bypass switches associdted for the three fastest with those control rods which operable control rods are fully ot partially withdrawn of all groups of four and are not within the 100-50 | |||
~ | |||
control rods in a percent rod density groups. Xn two-by-two array order to bypass a rod, the shall be 'no greater actual rod axial position. must than: be known; and the rod must be in | |||
% Inserted From Avg. Scram Inser- the correct in-sequence position, 5 0~ 398 | |||
: 2. At 16 week intervals, 10$ of the 20 0. 950 operab'e control tod drives 50 2 120 shall be scram timed above 90 3. 800 800 psig. ttlhenever such scram time measurements are made, an | |||
: 3. The maximum scram evaluation shall be made to insertion time for. provide reasonable assurance 90% insertion of any that proper control rod drive operable control rod performance is being shall not exceed F 00 . | |||
maintained. | |||
seconds. | |||
;6~ 128 | |||
Unit 3 LIHITZNG COVDZTIGNS FOR OPERATZO>i SURVEZLLAHCE REqUZREMZNTS 3e7 COW'AX%i..NT S STEM,S 4e 7 CONGA.XN!-'.P.NT SYSTEMS C'e Secondar Containment Co Secondar I Containment 0 Secondary ccntainment I | |||
~ 1~ Secondary containment integrity shall be surveys,llance shall be maintained in the 'erformed as reactor zone at all indicated belo~: | |||
times erce"t as specified in 3.7.C.2. | |||
~ LIMITINC CONDITIONS FOR OPERATION SgRVQILLANCE REQUIRENENTS 3~ 7 COhTA ANENT SYSTEMS 4 7 OtZM NHKNT S ST MS Secondary containment capability to maintain 1/4 inch of water vacuum under calm wind (<5 mph) conditions > | |||
vith a system inleakage rate of not more than 12 F 000 cfm, shall be | |||
'emcnstrated at each refueling outage prior to refuelinq. | |||
: 2. If reactor. zone 2. After a seccndary secondary containment containment vio1ation integrity cannot be is determined the maintained the standby gas treatment following conditions shall be met: | |||
'system vill be operated in mediately after the affected | |||
: a. The reactor . zones are isolated shall be made from the remainder of subcritical and the secondary Speci fication containment to 3.3.h shall be confirm its agility mete to maintain the | |||
: b. The reactor remainder of the shall be cooled secondary containment down belov 2124F at 1/4-inch of water and the reactor negative pressure coolant system under calm vind vented. conditions. | |||
c~ Fuel movement shall not be permitted in the reactor zone. | |||
: d. Primary con ta inment integrity | |||
'aintained. | |||
4 PROPOSED CHANGE TO UNIT 3 TECHNICAL SPECIFICATIONS APPENDIX B | |||
-17 Monitoring uill be performed usinu standard accepted smpling procc".urea vhich arc on file in the office,of the Division of Forestry, Fisheries, and Mildli.e Development, Norris, Tennessee. | |||
. Re ortinr Becuiremcnt The rerults vill be su~ari:zed annually in the annual reports of the nonradiological environmental monitoring program. | |||
Baoes A significant proportion of the river floe vill be routed through the plant for cooling purposes, end during perioas when larval fish are abundan there is the potential 'for entrainment of large nunbers of'ishes. | |||
The specified study vill determine the numbers of fish cr,.".s and larvae entrained in the cooler "~ eater systen resulting from pl .at operation and identiQ tt:e need for po"sible corrective action. | |||
(f) Fish imnin enent on Xntake Screens (Delete) | |||
ENCLOSURE 2 REASONS AND JUSTIFICATIONS FOR PROPOSED CHANGES TO BROWNS PERRY NUCLEAR PLANT UNITS 1, 2, AND 3 TECHNICAL SPECIFICATIONS UNIT 1 A endix A Page ll, Sections,2.1. J add 2.1.K: | |||
Proposed changes to these setpoints from +490 inches to 4470 inches. This was omitted in an amendment approved by NRC on August 2, 1978, concerning low water level setpoints. | |||
Pages 40, 41, 47, and 48: | |||
These proposed changes consist of adding an explanatory note to Table 4.1.B, changing LPRM to APRM in 4.1 Bases, and changing 4.1 Bases for clarification of LPRM-APRM requirements. The purpose of these changes is to correct previous typographical errors and to clarify calibration requirements. | |||
Page 124, Section 4.3.C.l: | |||
The proposed change allows post refuel outage control rod drive scram timing to be conducted in parallel with the vessel hydrostatic leak test, thus saving about one day in the startup test sequence. The reduction in required test pressure from 9SO psig to 800 psig is conservative in that the scram performance (insert speed) generally decreases accordingly. As can be seen from the attached figure (Attachment 1) which specifies a maximum-minimum scram performance band, the scram time change is insignificant over the desired pressure reduction. The data presented in the attached figure is only applicable to single CRD scrams with charging valve closed or full reactor scram with changing valve open. Scram time is the time from lode og voltage to scram air pilot valves to 90 percent insertion. This data was obtained from General Electric startup test procedures which is a part of the Browns-Ferry RTI5. | |||
~Aendix A continued Pages 240, 241: | |||
Proposed to delete section 4.7.C.la from the technical. | |||
specifications and to reletter the remaining paragraph from b to a. This specification is no longer applicable to Browlls Perry as all preoperational tests are completed and the requirement to test secondary containment integrity once per cycle is specified in 4.7.C-lb to become 4.7.C-la. | |||
~Aenddx B Page 17: See Attachment 2 UHXB 2 | |||
~Aendix A Page ll, 'Sections 2.1.J and 2.1.K: | |||
Same as unit 1 above Pages 40, 41, 47, and 48: | |||
Same as unit 1 above Page 124, Section 4.3.C.1: | |||
Same as unit 1 above Pages 240, 241: | |||
Same as unit 1 above | |||
~Aendix B Page 17: See Attachment 2 | |||
UNIT 3 | |||
~Aendix A Page 13, Sections 2.1eJ and 2.1.K: | |||
Same as page 11 for unit 1 above Page 39, 40, 46, and 47: | |||
Same as pages 40, 41, 47, and 48 for unit 1 above Page 128, Section 4.3.C.l: | |||
Same as page 124 for unit 1 above Pages 251,'52: | |||
Same as pages 240, 241 for unit 1 above | |||
~Aendix B Page 17: See Attachment 2 | |||
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ATTACHMENT 2 | |||
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JUSTXFICATIOH POR PROPOSED ETS CHANGE The attached report vas submitted to EPA on February 13, 1978, as a portion of TVA's 316(b) demonstration. The assessment of the effect of impingement of fish on the intake screens at Browns Perry Nuclear Plant provides the )ustif5cation for the proposed technical specification change. | |||
In sununary, the assessment concludes that impingement on the Brows Perry intake has no significant adverse effect on the fisheries resource of Wheeler Reservoir. | |||
EFFECTS OF IMPINGEHENT AT BROWNS FERRY NUCLEAR PLANT ON THE POPULATIONS OP PISH IN WHEELER RESERVOIR January 1978 Division of Forestry, Fisheries, and Wildlife Development Fisheries and Waterfowl Resources Branch | |||
INTRODWCTrnN The Browne Ferry Nuclear Plant is TVA's largest aperatlng steam sle>>I rl< llenor¹l lng pl>>bi, h~vlnll ¹ threr>>>>IL d¹¹lgn c¹pni'lly of j,456 megawatts (MW). The plant l,s located on the north bank of Wheeler Reservoir in north central Alabama at Tennessee River Mile 294.4. Initial criticality of units 1, 2, and 3 vere as follows: unit 1-August 16, 1973, unit 2-July 20, 1974, and unit 3>>August 8, 1976. Between March 27, 1975, and August 31, 1976, no electricity was produced due to an outage caused by a fire. | |||
During this time a reduced flov of water was pumped through the cooling water intake. | |||
Impingement monitoring vas continued uninterrupted from February 1974 through December 1977. It is currently being continued as part of the require-ments of the operating license issued by the Nuclear Regulatory Commission and in accordance vith the format described in the environmental technical specifications for Brovns Ferry. | |||
Descri tion of the Coolin Water Intake and Pum in Station The cooling water intake at Browne Ferry consists of a shoreline skimmer wall, an intake channel, a cooling vater return channel, and a concrete pumping station located at the end of the intake channel (Figure 1). Water passes through three openings in the skimmer wall. Each opening is 12.2 m wide and 7.3 m deep. The tops of the openings are located 3 m below normal maximum pool elevation. | |||
The intake channel is 150 m long from the skimmer vali to the pumping station. At normal maximum pool the water depth slang a 6.1 m vide area in the middle of the channel is 10.1 m. From there the sides of the channel slope at a 3:1 ratio. Directly in front of the pumping station the bottom slopes dawn | |||
C | |||
- ~ ? | |||
.0 J D O'L." lg | |||
--.~:" ' C'-.-.-=: | |||
C+>> 4 | |||
.jp ' f4 L | |||
' I kr | |||
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tf Alt L'O>> * | |||
' rP' 'L | |||
~ | |||
g | |||
~ r v 8 ~ | |||
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1 | |||
'I % ~ LW~V r | |||
'L | |||
~ | |||
~ | |||
+t ', V | |||
- ci Q | |||
PD, fi 'Q | |||
~'pure l. .":er='al;"ev of Brovns | |||
.='err@ H 'lear Plant | |||
: t. tK F 0 ttt h ~ | |||
.g~C p | |||
-:q | |||
~re l. her'al V'ev of Brovns Per".y ti. "lear PLant t, | |||
an additional 1.5 m to the bottom of the intake opening, resulting in a maximum depth of 11.6 m at the intake screen at normal maximum pool. | |||
The cooling tower return channel enters the left side (facing the I | |||
pumping station) of the intake channel (Figure 1). Pish movement up the cooling tower return channel is precluded by a concrete wall located several hundred meters upstream from the intake channel. | |||
The 70.7 m long pumping station contains nine cooling water circulator pumps (three per unit) and 18 vertical traveling screens. Each pump 'contributes | |||
-1 13.9 m 3 sec for a total three-unit condenser and auxiliary demand of 124.9 m 3 sec -1 (1.98 million gallons per minute). | |||
Each of the endless-belt vertical traveling screens is housed in I a . | |||
separate intake screen well measuring 2.6 m wide (inside dimensions). The trashrack opening for each intake well measures 1.6 m wide by 7.3 m high. The screen panels are 2.3 m wide and support a square mesh steel screen having 9.5 mm (3/8") openings. At 9.8 m of water depth in the intake well, each 3 -1 screen is designed to piss 6.9 m sec (110,000 gpm) through a clean surface at | |||
-1 a velocity of 61.0 cm sec (2.0 fps). The screens are cleaned either on a regular basis (such as shift changes or daily) or after a maximum pressure differential develops across the screens due to clogging. The long impingement time for fish in addition to exposure to the high pressure spray system during the cleaning process results in essentially 100 percent mortality of impinged fish. | |||
METHODS Two procedures for estimating impingement were used during the monitoring period. From March 1974 through July 1976 the following method was employed: expansion factors were calculated every two months (or less) | |||
for each screen by counting from each screen in use all fish impinged during four consecutive 12-hour (day/night) periods. An expansion factor for each screen vas calculated simply by dividing the total fish for all screens by the total for each screen. These expansion factors vere employed in subsequent impingement counts to estimate total impingement on all screens from a count of fish from one test screen. Three times per week all fish impinged on the test screen (or alternate screen) vere counted. To estimate 'the total impinge-ment for all screens, the expansion factor for that screen vas multiplied by the number of each species impinged on the test screen. If one or more pumps were not in operation, a correction formula vas used to adjust the total estimated number impinged. Revision'-of the environmental technical specifications in September 1976 changed these impingement monitoring procedures. Coincident vith the startup of Unit 3, this revision required a direct count o! fish from each screen during one 24-hour period each veek. | |||
Test Procedures Twenty-four hours prior to each impingement count, all screens vere simultaneously rotated and vashed to remove impinged trash and fish. The screens were then stopped for a 24-hour test period. The test screen (in early tests) or each screen in operation (in later tests) vas 'vashed individually after, the 24-hour test period. The fish vere collected in a large basket at the end of the screen wash water sluice conduit. These fish vere then sorted into species by 25 mm total length increments. The number and total veight (gm) for each size class vere recorded for each species. When excessive fish precluded a direct count of all fish, subsampling within species was conducted. All impinged fish, including those impinged during sampling days as I veil as during days of routine screen cleaning, vere deposited in a sanitary landf'ill. | |||
Cooli Mater Intake Velocities Intake ~ster velocities were measured on May 18, 1977, during operation of all nine condenser circulating pumps. The average velocity through the three skimmer wall openings was 29.6 cm sec 1, 28.0 cm sec 1 and 32.0 cm "ec" . Overall, individual measurements ranged from 7.0 to 50.0 cm sec -1 . The mean cross section intake channel velocity 100 m upstream of the pumping station was 38.4 cm sec . Velocities ranged from 27.0 to 48.0 cm sec | |||
-1 . Seventy-five velocity measurements taken 1 m in front of the 18 trashracks averaged 36.6 cm sec and ranged from 18.0 to 50.0 cm sec 1. | |||
Numerical Anal sis For analyzing and comparing the impingement data, three distinct 12-month periods were identified. These are based on the level of plant operation. The first operational period extended from March 27, 1974, shortly after impingement monitoring was initiated, until March 27, 1975, when fire interrupted plant operation. This period included Unit 1 operation from March 27, 1974-August 27, 1974, and Units 1 and 2 operation from August 28, 1974-March 27, 1975. The average number of pumps in use on the sampling days was 4.6. | |||
The second period included the first 12 months of no electric generation following the fire. During this time a reduced water flow was pumped through the intake. The average number of pumps in use was 2.4. | |||
The third operational period represented the first 12 months of normal operation after the fire. During this period all three units were | |||
placed in operation, with an average of 7.2 pumps in operation. on sampling days ~ | |||
An estimate of total impingement for these three 12~nth periods was obtained by calculating averages of daily (24-hour) impingement as determined by either of the two procedures described above. Average daily estimates for each species were then multiplied by the number of days | |||
.in each period. | |||
Differences in total observed impingement (all speciea combined) between intake screens were examined for each level of plant operation using the Kruskal-Wallis procedure (Hollander and Wolfe 1973). Only those samples in which counts were obtained from all screens (6, 12, or 18 for 1 e 2 ~ or 3 unit operation, respectively) were used in the statistical procedure. Multiple comparisons of impingement by sc'reen were made using a nonparametric procedure based on Kruskal-Wallis ranks (Hollander and Wolfe 1973). All test statistics were examined for significance at the a 0.05 level. These data were also examined graphically by plotting the pooled proportion impinged on each screen for each operational period. | |||
'I Differences between day (0600-1800 hours) and night (1800-0600 hours) impingement were examined for each species for which total observed impingement (all day/night test periods combined) was equal to or greater than 1,000 individuals. A replicated goodness-of-fit procedure using the G statistic (an alternative statistic of the more common X ) was used to test the null hypothesis 2'hat the proportion impinged during the day was equal (0.50) to impingement during the night (Sokal and Rohlf 1969). Test statistics were examined for significance at the a 0.05 level. For each species examined, the pooled proportion impinged during the day and night periods was presented graphically. | |||
/ | |||
Size distribution of impinged fish was examined for: skipjack herring, gizzard shad, threadfin shad, channel catfish, white bass, yellow bass, green sunfish, bluegill, redear sunfish, white crappie, sauger, and freshwater drum. For each of the 12 species, a frequency histogram (percentage) of length class was prepared summarizing all available size information collected from March 1974 to August 1977. | |||
The determination of possible adverse impact by impingement was facilitated by the comparison of estimated 12-month impingement for selected species with numerical standing stock information for the same species derived from cove rotenone data. Within each operational period, those species were selected which showed estimated 12-month impingement ~ 365 (one individual per day). For each operational period, standing stock information for corre-sponding summer months was expanded to a total number for Wheeler Reservoir. | |||
This total number was calculated by multiplying the mean number per hectare by the total surface area of the reservoir. For each species, this expansion was performed separately for both young-of-year (based on length class) and all I | |||
size classes combined. Estimated number impinged for each species was then divided by total and young-of-year standing stock estimates for Wheeler Reservoir, resulting in an estimated proportion (expressed as percent) for each length class removed by impingement (referred to as relative impingement in this report) at the intake of Browns Ferry Nuclear Plant. This method of estimating impact on reservoir populations has one primary limitation--the assumption that for each species in question, cove rotenone data accurately estimate reservoir standing stock. | |||
ggy<']s<< jJpQ -gL<< Ppl< << III I <<<<~<<<<s IL I<<I< | |||
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I<<< < I <<g < I<8 I <<<I< I << II<<<<<e<< I <<<<<<< I I <<< I <<g I<<<< I <<<I H<< I < I< I J /4 A<< II<<s I I lI/ | |||
12 species were <:ol.lected (Table l). During summer cove samples taken in 1974-i977, 60 species" were collected from a total of 15 cove-samples collected in Wheeler Reservoir. Of the species collected from the intake screens, four represented 95.8 percent of the total'observed impingement. These were threadfin shad (76.5 percent), gizzard shad (12.3 percent), freshwater drum (4.3 percent), skip)ack herring (2.7 percent) and were the only species which individually represented more than 1 percent of the total observed impingement. | |||
In cove samples nine species each exceeded 1 percent of the total numerical standing stock for all three years combined: threadfin shad (37.1 percent), | |||
gizzard shad (28.0 percent), bluegill (16.8 percent), longear sunfish (6.4 percent), redear sunfish (1.6 percent), bullhead minnow (1.4 percent), logperch (1.4 percent), warmouth (1.3 percent), and freshwater drum (1.0 percent). None of the species impinged is currently classified as "threatened" or "endangered." | |||
Estimated Total I in ement During the first operational period, March 27, 1974-March 26, 1975, an estimated 5.26 million fish of 50 species were impinged (Table 2). Four species (skipgack herring, gizzard shad, threadfin shad, and freshwater drum) comprised 97.7 percent of the total. Thirteen additional species exceeded an estimated 1,000 individuals impinged during the 12-month period including silver chub, emerald shiner, spotted sucker, blue catfish, channel catfish, white bass, yellow bass, green sunfish, bluegill, redear sunfish, white crappie, logperch, and sauger. | |||
During the 12 months which followed the fire at Browne Ferry (second operational period), the total estimated number impinged dropped from the | |||
Table l. Species list and percent of total for all fish collected from the Browne Ferry intake screens during the monitoring period March 1974-August 1977 and all species collected in 15 cove rotenone samples collected in Wheeler Reservoir in 1974N 1975, 1976, and 1977. | |||
Percent, Percent Composition Composition Common Name Scientific Name (Impinged) | |||
(Cove)'hestnut lamprey <0. 01 NC Paddlefioh, ~Pol odon ~sschula <0. Ol NC Spotted gar ~Le isoeteus oculatus <0. Ol 0. 02 Longnose gar ~Le isosteus osseus <0. Ol <O. 01 Shortnose gar ~Le isosteus platostomus <0. 01 NC Skipjack herring 2. 72 0. 16 Gizzard shad Deepsome ~ce edianum 12. 30 27.95 Threadfin shad Doroooms Hetenenss 76.49 37.08 Rainbov trout Helmo Helrdnari <0.01 NC Mooneye Hiodon ~ter isus 0. 01 NC Grass pickerel Esox americanus vermiculatus <0. 01 NC Chafn pickerel Rv<ix ~i, sr <0. 01 NC Stoneroller ~Cem ostoma enema'lum <0. 01 0,01 Goldfish Carassius auratus <0. 01 NC Carp ~trdnus ~car io 0. 02 0.01 Speckled chub ~mbo sis aesciualis <0. Ol NC Silver chub ~mba sie storerisna 0.23 0.27 River chub Nocomis ~micro o an 0.01 NC Golden shiner ~Notami onus ~cr soleucss 0. 04 O.OS L" a | |||
Emerald shiner. ~Nocto is athetinoides 0.12 0.10 t Ghost shiner ~motto is buchenani 0.01 NC Common shiner ~Nocto is cornutus NI" 0. 01 Striped shiner NI <0. Ol shiner 'osyface | |||
~Notxo ia rubellus <0.01 NC Spotfin shiner ~Nocto is ~silo cerus <0.01 0. 02 | |||
10 Table 1. (Continued) | |||
Percent Percent Composition Composition Common Name Scientific Name (Impinged) (Cove) | |||
M;;min shiner ~Notre is vhlucellus <0.01 0.04 Steelcolor shiner ~Notre ie ~vhi le1 NI 0. 01 Bluntnose minnow ~Pine hales notatue NI NG Fathead minnow . ~PIns hales Hronelas < 0.01 <O. 01 Bullhead minnow ~Pine hales ~vt 1lsx 0. 02 1.38 Blacknose dace ~Rhtnichth s atratulus <<0.01 NC Longnose dace ~Rhtnichth s cetaractae < 0.01 River carpsucker ~Car iodee ~car io < 0.01 <0.01 quillback ~Car iodes ~crtuus <0.01 NC Highfin carpsucker ~Csr iodes veliier NC Northern hogsucker ~Henteliun ~ni ricans <0. 01 <0.01 Smallmouth buffalo Ictiobus bubalus t | |||
: 0. 01 0.09 Bigmouth buffalo Ictiohue ~crknellus <<0.01 <0.01 Black buffalo Ictiobus ~ni er <0. 01 <0. 01 / | |||
Spotted sucker ~MIn treaa ~nelson s 0. 07 0.92 Silver redhorse Moxostoma anisurum < 0.01 0.02 River redhorse Moxostoma carinatum <0.01 <0.01 Shorthead redhorse < 0.01 <0.01 Black redhorse Moxostocn ~du uesnei <0.01 <0. Ol, Golden redhorse Moxostona errthrurnn < 0.01 0.11 Blue catfish Ictalurus furcatus 0. 08 <0.01 Black bullhead Ictalurus melas 0.02 <0.01 Yellow bullhead Ictalurus natalis <0.01 NC Brown bullhead Ictalurus nebulosus 0.01 NC Channel, catfish Ictalurua punctatus 0.39 0.13 Slender madtom Noturus exilie <0. 01 v | |||
Flathead catfish ~Plodtctie olivarie 0.03 0.05 Blackstripe topminnow Fundulus notatus NI 0.02 Blackspotted topminnow Fundulus olivace<<s < 0.01 0.11 Mosquitofish Gambusia affinis < 0.01 0.03 Brook silverside Labidesthes sicculus < 0.01 0. 10 | |||
Table I, (Continuod) | |||
Porcnnt Prrr~ nt Composition Composition Common Name Scientific Name (Impinged) (Cove) | |||
White bass Morone chrh~eo e 0.55 0. 12 Yellow bass Morone ctaste~st 'anais 0.92 0.3& | |||
Striped base Horonc onxatIl In <0.01 NC Rock bass Am~bio Platen r~u>>strip <0.01 <0.01 Redbreast sunfish ~ta osis naritus < 0.01 HC Green sunfish ~te o is ~ccnellus 0.33 0.40 Wnrmouth- ~Le o ta guineas 0. Ol 1.29 Orangespotted sunfish ~Le oats huetlls <0.01 0.20 Blue'ill ~Le oats aacrouhirus 0.72 16.78 Longenr sunfish L~eoels a~enlatts 0. 08 6s37 Redenr sunfish I~eomis micro o~hue 1 0. 24 1.84 Spotted sunfish ~Le oats punctntue < 0.01 NC Smnllmouth bass Mt~era terus dolanieut <0. 01 0.21 Spotted bees ~Mtcro rerun Munctulatus 0. 01 0. 16 Largemouth bass Micro terus ealaoides 0. 02 0.60 White crappie Pomoxlo nnnulnris 0.11 0.11 Blnck rrnppi>> Pomox to n t~romnculntus 0.01 r0.01 Fantail darter 8th>>ootomn flnbellave NI 0.04 Stripetnil darter Etheootomn kennicotti NI 0.12 Redline darter Htheostoma rufilineatum NI <Oe01 Yellow perch Perca flavescene NI <0. 01 Logperch Perctrs ~ca rodes 0.04 1. 39 Dusky darter Porc lna eciera < 0.01 <0;01 River darter Perr.lna ohumnrdi < 0.01 0. 03 Souger Stizootedion canadense 0.05 0.13 Walleye St izoo ted ion vi treum vit reum < 0.01 NC Freshwater drum A~lodtnotus Mrunuteca 4.34 I '.02 I., Not collected in rotenone nnmplrdd. | |||
Not observed in impingement snmplee'. | |||
LL Table 2 Estimated total number of all fish impinged at Browne Ferry Nuclear Plant between March 27, 1974-March 26, 1975 Total Estimated Number 'Total Eat (mated Impinged i' Number lmpf nged TLxb 150 Samples Lamprey 10 24 Chestnut lamprey 5 Psddlefish 69 168 Spotted gar 66 160 Longnose gar 27 Shortnose gar 5 Skipgack herring 90,807 220,964 Gizzard shad 75,440 183,571 Thresdfin shad 1,824,188 4>438,857 Dol'osoela sp 48,937 119,080 Mooneye 179 437 Goldfish 91 221 Carp 85 207 Silver chub 3,553 8,646 Golden shiner 271 660 Emerald shiner 1>269 3>OSS Bluntnose minnow 2 5 Fathead minnow 22 53 River csrpsucker 3 7 Quillback 5 12 Smallmouth buffalo 105 255 Bigmouth buffalo , | |||
Spotted sucker 431 1,049 Redhorse sucker 6 14 Catfish 2 Blue catfish 1>641 3,993 Black bullhead 366 892 Yell'ow bullhead 14 33 Brown bullhead 1 2 Channel catfish 8>924 21,716 Flathead catfish 209 508 | |||
Table 2~ (Continued) | |||
Total Estimated Number Impinged In Total Estimated Taxa 150 samples Number Impinged Nosquitofish 6 14 White bass 5,805 14,126 Yellov bass 5, 940 14;453 Striped bass 21 51 Rock bass Redbreast sunfish 3 Green sunfish 4,173 10,154 Warmouth 160 390 Orangespotted sunfish 57 Bluegill 7,214 17 .556 Longear sunfish ~ | |||
150 366 Redear sunfish 3,250 7,910 Smallmouth bass 10 25 Spotted bass 24 59 Largemouth bass 136 332 White crappie 3,216 7,826 Black crappie 27 67 Logperch 927 2,256 Darter 1 2 Sauger 1,516 3> 690 Walleye 16 39 Preshwater drum 73 766 179 501 Total 2>163 >098 5,263,546 | |||
14 preceding period to 2.69 million fish of 52 species (Table 3). The three clupeids (gizzard shad, threadfin shad, and skip)ack herring) and !reshvatsr drum comprised 9&.2 percent of all fish collected. Seventeen additional species that exceeded an estimated 1,000 individuals for the 12-month period were carp, silver chub, emerald shiner, ghost shiner, spotted sucker, blue catfish, black bullhead, channel catfish, flathead catfish, vhite bass, yellov bass, green sunfish, bluegill, redear sunfish, vhite crappie, logperch, and sauger. | |||
During the third operational period of three-unit operation, (September 1, 1976<<August 31, 1977) an estimated 6.67 million fish representing 61 species vere impinged (Table 4). During this period, the three clupeids and freshvater drum were again dominant and comprised 94.6 percent of the total, vhile 19 additional speciea vere each estimated to have been impinged in total numbers exceeding 1,000 each. These species vere silver chub, golden shiner, emerald shiner, bullhead minnow, spotted sucker, blue catfish, brovn bullhead, channel catfish, flathead catfish, vhite base, yellov bass, green sunfish, bluegill, longear sunfish, redear sunfish, largemouth bass, vhite crappie, logperch, and sauger. | |||
P Estimated total weight of each species impinged was also calculated. | |||
for samples collected during the third operational period (Table 4). Total weight estimated for all fish impinged during this period vas 63 metric tons. | |||
Seasonal Patterns of Im in ament Figure 2 depicts the total impingement estimated by month for the period March 1974-August 1977. Clupeids showed a consistent pattern of lowest impingement in May or June. Impingement vas usually highest from December through March. An exception was 1976-1977 when clupeid impingement peaked during September-October. | |||
15 Table 3 . Estimated total number of all fish impinged at Brovns Perry Nuclear Plant betveen March 27, 1975-March 26, 1976. | |||
Total Estimated Number Impinged . In Total Estimated Taxa 152 samples Number Impinged Lamprey 23 Paddlefish 15 Spotted gar 481 Longnose gar 21 Shortnose gar 13 31 Skip)ack herring 41,011 98,751 Gizzard shad 142,578 343,312 Threadfin shad 793,013 1,909,492 Mooneye 144 346 Grass pickerel Goldfish 17 Carp 471 14134 Silver chub 2,703 64509 River chub 2 6 Golden shiner 161 388 Ps~sss s sp. | |||
Cmefdid shiner 922 2,200 Ghost shiner 608 1,464 Spotfin shiner 20 Bluntnose minnov 11 Pathead minnov 13 32 Bullhead minnov 303 730 Blacknose dace 5 ll River carpsucker ll 25 illback 2 4 Smallmouth buffalo 332 800 Bigmouth buffalo 16 Black buffalo Spotted sucker 1,320 3,178 Redhorse sucker 47 114 | |||
16 Table 3 . (Continued). | |||
Total gstimated Number Impinged In Total Estimated Taxa 152 samples Number Impinged Blue catfish 1,029 2,476 Black bullhead 493 1 ~ 187 Yellow bullhead 54 129 Brown bullhead 15 Channel catfish 4,749 11,435 Flathead catfish 436 1,050 White bass 5,569 j3,408 Y~llw hs<S I$ ,n')s Green sunfish 1 ~ 294 3oll5 Warmouth 103 248 Orangespotted sunfish 19 Bluegill 3,913 9 '23 Longear sunfish 188 452 Redear sunfish 1,064 2 '61 Smallmouth bass 3 8 Spotted bass 328 791 Largemouth bass 234 564 White crappie 2,075 4,996 Black crappie 15 37 Logperch 702 1,690 Barter 5 Sauger 767 1,846 Freshwater drum 97,140 2331902 Total 1,116,545 2e688e498 | |||
Table 4 ~ Estimated t.ot al numb@i and Meight of all fish species impinged at Srowns Perry Nuclear Plant between September 1976-August 1977. Estimates are ba'sed on 54 24-hour samples collected at one-Meek intervals. | |||
Total Est. Number Total Wt. (kg) | |||
Taxa Impinged In 54 sam lea Impinged In 54 aam les Total Pst. No. | |||
Ttmfn6ad ~leTotal Est. Wt.(kg) ingate lamprey 12 0.61 81 4.10 'hestnut Paddlefish 0. 21 14 1.45 Spotted gsr 19 10.93 128 73. 85 Longnose gar 0.85 5.73 Shortnose gar 4.94 74 33.38 Skipgack herring 16,346 171.35 110,487 1,158.23 Gixenr<l Hhad 200,305 4,235.89 1,353.913 28,631.50 Threadfin shad 68'>,769 2,189.22 4.635,290 14,797.49 Mooneye 97 15.95 656 107.78 Chnin pickerel l. 36 14 9. 21 Stoneroller .03 0.20 Goldfish 36 8. 83 243 59. 66 Carp 10 5.03 68 34.00 Speckled chub 0. 08 27 n. 5> | |||
Silver chub l,115 24.42 7,537 )65.07 Hfver chub 0.)2 0.72 Golden shiner 817 16.83 5,522 113. 78 Emerald shiner 1,184 7.84 8,003 53.01 Ghost shiner 10 0.02 68 0.16 Mimic shiner 33 0,06 223 0. 41 Bullhead minnow 182 1. 90 1,230 12.82 Longnose dace 0. 01 0.05 Quillback 0. 11 74 0.75 Northern hog sucker 0 '4 14 3. 63 Smallmourh buffalo 125 48. 95 845 330.86 Bigmouth buffalo 2. 24 34 15.13 Spotted sucker 1,094, 69.33 7,395 468.61 Silver redhorse 15 5. 94 101 40.16 Shorthead redhorse 0.60 4.04 Black redhorse 2.11 37 14.27 Golden redhorse 19 8.22 128 55.55 | |||
18 Table 4. (Continued) | |||
Total Est.Number Total Est. Wt.(kg) Total Est.No. Total Est.Wt.(kg) | |||
Impinged In Impinged In Impinged Impinged Taxs 54 samples 54 samples Blue catfish 379 33.79 2,562 228.40 Black bullhead 88 1.80 595 12.15 Yellow bullhead 0. 08 7 0.55 Brown bullhead 263 16.01 1>778 108.18 Channel catfish 3,657 175.22 24,719 1>184.36 Flathead catfish 328 9.91 2,217 67.01 Black Spotted topminnow <0. 01 7 0. 01 Brook silverside <0.01 20 0. 03 Rnite bass 7,498 131.19 50,681 886.71 Yellow bass 9>913 234.08 67,005 1,582.21 Striped bass 30 2.26 203 15. 26, Rock bass 0. 04 14 0. 30 Green sunfish 5,801 40 ~ 54 39,210 274.05 Warmouth 58 1.26 392 8.51 Orangespotted sunfish 0. 03 14 0.20 Bluegill sunfish 12,572 285.70 84,977 1,931.13 Longear sunfish 1,374 10.68 9,287 72.18 Redear sunfish 4,087 184.93 27,625 1,249.96 Spotted sunfish 1 0.04 7 0.25-Smallmouth bass 47 2.80 318 18.93 Spotted bass 50 l. 53 338 10. | |||
Largemouth bass 262 17.42 1>771 36'17.75 White crappie 1,003 23.04 6,780 155.75 Black grapple 86 4.69 581 31.69 Logperch 256 l. 70 1,730 11.49 Dusky darter 7 0. 03 47 0. 22 River darter 0.02 27 0. 12 Sauges,' 375 52. 74 2,535 356.48 Walleye 3 2.45 20 16.53 Freshwater drum 31 924 1 322.38 215 783 8 >38.31 987,310 9,390.88 6>673>488 63,485.19 | |||
19 1PSMOO Q Clupeld S1lg00 All older isis | |||
~ | |||
acoeoo 20~00 102'O I | |||
a+00 l | |||
2QIOO I. | |||
I 12@00 6 | |||
K | |||
~00 C | |||
D v QOO | |||
~0 WOO SOb M A M J J A S 0 N D J F Month 7d Figure 2. Total estimated monthly impingement at Browne Perry Nuclear Plant for Clupeids (shad) and all remaining taxa during the period March 1974-August 1977. A geometric scale vas required to shou the large range in monthly values | |||
'l 20 | |||
+38p$ 00 Clllpold All other togo 6it+00 ' | |||
409/00 \ ~G 204/00 0 102/00 I | |||
O'QOO 26@00 C | |||
" | |||
12POO I | |||
I. | |||
h CL I | |||
O ~00 C | |||
'0 QOO E | |||
~4 N | |||
4+00 800 100 M A M J J A S 0 H 0 J l'onth | |||
,14 Figure 2. (Continued) | |||
~ All elhi ~ lIRI St I+00 I 409/00 dS 204/00 ', | |||
A, 10+00 I I | |||
SHOO 26Jt00 | |||
\ | |||
\ 0 o 12@00 E | |||
00 C | |||
'0 00 E | |||
+00 | |||
) l 11 j | |||
$ 00 400 | |||
' " J 4 S 0 N 0 J F Month Figure 2 (Continued) | |||
22 fp88r400 QCtopota All other taxo StaP00 400/00 204gl00 to&00 5+00 25/00 C | |||
E taP00 CL | |||
~00 C | |||
D | |||
)I 3/00 E | |||
Ol | |||
~00 600 400 M A M J Month Figure ~ (Cont:inued) | |||
23 Lowest impingement of clupeids during May-June was followed by a sharp increase in July and August for the first three years of record. This probably refl'ects the appearance of young-of-year. However, the pattern did not hold for the last year of data. Numbers remained low through August, the last month reported. Monitoring not reported here showed that threadfin shed impingement did not increase through December 1977. The impingement of low numbers of clupeids after June 1977 is likely associated with a very low'ensity of young-of-year I | |||
threadfin shad in Wheeler Reservoir. Nonshad taxa showed a pattern of generally irregular fluctuations in monthly impingement between 6,000-60,000 fish (Figure 2). | |||
Highest impingement often occurred in March with the highest value in March 1977. | |||
Co arison of Da and Ni ht Im in ament Species selected for detailed examination of day versus night fmpfngemenf, were: skip)ack herring, gissard shad, threadfin shad, silver chub, emerald shiner, spotted sucker, channel catfish, white bass, yellow base, green sunfish, bluegill, longear sunfish, redear sunfish, white crappie, and freshwater drum. | |||
The replicated goodness-of-fit procedure indicated significant departure from the null hypothesis (impingement during the day impingement during the night) for all 15 species (Table 5). For two species, green sunfish and longear sunfish, pooled G-values were not significant even though total G-values were significant. | |||
Thus, if all replicates for these two species were treated as one observation, we would accept the null hypothesis stated above. Much of the variability in t'e analyses was accounted for by heterogeneity among the replicates. Thus, . | |||
differences between.day and night impingement ware not consistent between replicates for all species treated. | |||
The data in Figure 3 show that for all but one species (longear su<<tish) the pooled proportion of fish impinged during night was greater than during daylight. | |||
24 Table 5. Results of replicated goodness-of-fit analyses comparing day and night impingement for 15 selected species. The G-value labeled "Het." | |||
represents the statistic to test the hypothesis that all replicates were homogeneous, i.e., ware drawn from the same population. This value was calculated as the difference; Total G-value - Pooled G-value Hetero-gelleity G value ~ | |||
Number G-Values Species Day Night Total Pooled Het. | |||
Skip)ack herring 81624 24,533 14,306. 7* 7o957 ~ 0* 6,349.7* | |||
Gizzard shad 9,943 14,171 21025. 7* 745.2e 1,280.5* | |||
Threadfin shad 96,563 181,917 62,308.3* 26,586.8* 35,721.5* | |||
Silver chub 502 1I 053 314.8* 199.5* 115.3* | |||
Emerald shiner 180 426 185.1* 102.8* 82.3* | |||
Spotted sucker 18 42 39.8* 9 '* 30oO+ | |||
Channel catfish 589 858 193.8* 50. 3* 143.5* | |||
White bass 266 991 647.0* 445.1* 201.9* | |||
Yellow bass 65,9 11216 358.2* 168oO* 190.2* | |||
Green sunfish 99 56.9* 3.5 53.5* | |||
127'531 Bluegill 858 205.3* 77 ~ 7* 127.6* | |||
Longear sunfish 42 34 36.5* 0.8 35.6* | |||
Redear sunfish 70 169 125.1* 42.3* 82.8* | |||
White crappie 145 335 168.8* 77.3+ 91. 5" 5'fn~ftosfct Atua 6,08 3 I t>,829 3,864.3< 1,349.9* 2, '514. | |||
level of confidence. | |||
4<'Statistically significant at the a ~ 0.05 | |||
2> | |||
Percent | |||
.2 2 .$ 0 .75 sqo SkipJack herring Gizzard shad Day 1$ 5RCNNRi Threadfin shad Might Silver chub Emerald shiner Spotted sucker Channel catfish White bass Yellow bass Green sunfish Bl ueg l 1 I | |||
,h. h hP Longear sunfish Redear sunfish White crappie Freshwater drum | |||
.50 .75 f00 Figure 3 Numbers impinged for selected species during the 12-hour periods 060'0.-1800 hours and 1800&600 hours. This graph depicts the results of 42 pooled day/night samples collected between March 19T4-November 1976. | |||
26 The seven species which showed the greatest tendency for impingement during the night were skipjack herring, silver chub, emerald shiner, spotted sucker, white bass, redear sunfish, and white crappie (Figure 3). For~each of these over two-thirds of the individuals were impinged during hours of darkness. | |||
Co arison of Im in ament Aeon Intake Screens Comparison of the distribution of impinged fish (all species combined) among screens for the three operational periods showed differences to be pro-nounced during one-unit (screens 1-6) operation (Figure 4). The Kruskal-Wallis procedure selected two subsets of difference among screens. Multiple comparisons selected two subsets of screens with similar impingement: screens 01, 02, 03, 04, 05, and screens 03, 04'5, and'6; During the second and third operational periods,'he frequency histogram (Pigure 4) suggested that higher impingement tended to occur on the end screens; however, no statistically significant differences among screens were detected. | |||
Size Distribution of I in ed Pish Pish smaller than 51 mm appeared to be relatively insusceptible to impingement for all 12 species examined (Figures 5 end 6). Over 70 percent of the impinged fish were between 51-100 mm total length for eight species: | |||
skipjack herring, gizzard shad, threadfin shad, channel catfish, white bass, yellow bass, green sunfish, and white crappie. Except for white crappie, those fish less than 101 mm total length are considered to be young-of-year. | |||
Individuals of 76-100 mm length represented over 30 percent of the impinged white crappie. White crappie of this s$ zc are probably io the second growth season. For the remaining four species (bluegill, redear sunfish, sauger and freshwater drum), fish more than 100 mm in total length accounted for a | |||
27 Unit 1 oynratton HI 4/40 are 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 Unit 1-2 operation tt 22raa2 20 g | |||
,10 01 02 03 04 05 06 07 Od 09 10 11 12 13 14 15 16 17 18 Unit 1-2 operation tts 27,241 | |||
&10 20 10 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 Screeae Figure 4 Distribotion of impinged fish (a11 species combined) among screens at Browne Ferry Nuclear Plant for three levels of plant generation. These comparisons include only those samples when all screens ware in use. N is the total number of fish in all 24-hour samples. S is the number of 24"hour samples ~ | |||
Skip)eck herring 0- 25 Gizzard shad 26- 50 51- 75 76-100 101-125 126-150 151-175 l76-Threadfln shad 0- 25 Channel catfish 26- 50 51- 75 76-100 101-125 126-150 15:I.-175 176-White bass Yellow bass 0- 25 26- 50 53- 75 76-100 | |||
)0)-125 126-150 151-175 176-100 75 50 25 Length Class 25 50 75 100 (mm) | |||
Percent Percent Fg~ute 5. l.ength frequency distrlbut ton for s< lected fish species Impinged nt, Browns Ferry Nuclear Plant during thc period Herch l974-August l917. | |||
29 Green sunfish 0- 25 8luegl l l 26- 50 51- 75 76-100 101 .'.25 126-150 151-175 176-Redear White crappie 0- 25 26- 50 51- 75 76-100 101-125 126-150 I | |||
7aaIL 151-175 ~ | |||
176- IIII 0- | |||
~ | |||
Sauger 25 Freshwater drum 26- 50 | |||
~ | |||
Ib a | |||
~ | |||
76 ioo 101-125 | |||
, 126-150 1 | |||
151-175 176-75 50 25 Length Class 25 50 75 100 (mm) | |||
Percent Percent Figure 6. Length frequency distribution for selected fish species impinged at 8rowns Ferry Nuclear Plant during the period Harch l974-August 1977. | |||
30 considerable proportion of the numbers impinged. Except for sauger, these larger sizes probably include fish older than young-of-year specimens. | |||
Com arison of Im in ement Estimates with Standin Stock E>>timates During the three operational periods, 30 species werc impinged at an. average rate f one or more. fish per day for at least one of the periods. | |||
Impingement of 1? of these species exceeded l percent of the estimated standing stock (numbers) for one or more operational periods (Tables 6-8). | |||
These included skip)ack herring, gizzard shad, threadfin shad, mooneye, carp, silver chub, blue catfish, black bullhead, brown bullhead, channel catfish, white bass, yellow bass, green sunfish, white crappie, black crappie, sauger, and freshwater drum. Six of these species (mooneye, carp, blue catfish, black and brown bullhead, and black crappie) were either absent or rarely collected in the cove samples. Except for blue catfish, the estimated average impingement of each of these species did not exceed an average of three individuals per day. The remaining species which were impinged at 1 percent or more of the estimated standing stock are discussed below. | |||
Ski ack herrin Estimated impingement of skip)ack herring decreased during the three operational periods while mean numerical standing stock values increased over the years corresponding to the operational periods (Tables 6-8). Thus, despite the lower intake flow and lower reservoir density of skip)ack herring during the first period, the proportion of standing stock removed by impingement was greatest in the first operational period and least during the third operational period (Tables 6-8). | |||
31 Table 6. Estimated standing stock numbers (based on cove rotenone samples) for selected species of fish in Wheeler Reservoir (1974) compared with estimated total imp5ngement of these sp'ecies during the period March 27, 1974-March 26, 1975. | |||
I Estimated Mean Standing Percent of standing stock Total No. ock No h numbers im in~ed Taxa Xmpinged YOY Total YOY Tota1 Skipgack herring 220,964 17.70 27.70 45.97 29. 38 Gizzard shad 190,914 873.05 1,768.30 .81 .40 Threadfin shad 4,553,174 2,447.84 2 '47.84 6. 85 6.85 5 5 Mooneye 437 NC NC Silver chub 8,646 54.26 54.26 0.59 0'59 Golden shiner 660 39. 06 39.06 0.06 0.06 Emerald shiner 3,088 28.85 28.85 0. 39 0.39 Spotted sucker 1,049 11.05 71.81 0.35 0.05 5 5 Blue catfish 3,993 NC NC Black bullhead 892 NC NC Channel catfish 21,716 l. 34 9.79 59.68 8.17 Flathead catfish 508 6.53 13.98 0.29 0.13 White I | |||
bass 14,126 3.61 4.46 14.41 j 1.66 Yellow bass 14.453 36. 66 36.66 1. 45 1. 45 Green sunfish 101154 19. 75 26.67 1.89 1.40 Bluegill 17,556 722. 08 1 I 120. 45 0. 09 0. 06 Longear sunfish 366 282.09 556.01 <0. Ol <0.01 Redear sunfish 7>910 138.01 209.35 0.21 0,14 White crappie 7,826 1.04 2.08 27.71 13. 86 Logperch 2,256 206.63 206.63 O. 04 0.04 Sau ger 3,690 5.90 7.04 2.30 1.93 Freshwater drum 179,501 51.31 102.86 12.88 6.43 | |||
: 1. Refers to young-of-year fish. | |||
: 2. Refers to all ages collected in suamer cove samples. | |||
: 3. Based on a reservoir surface area of 27,150 ha. | |||
: 4. Not collected on cove rotenone samples. | |||
'5. Calculation not possible., | |||
I | |||
32 Tabl<<7. E<<tom<<ted <<t<<nding stock numbers (based on cove rotenone samples) for selected species of fish in Wheeler Reservoir (1975) compared with estimated totnl impingemetg of these speciea during the period March 27, 1975-Hnrch 26, 1976. | |||
Estimated Harm standing I'or< ont of stan<ling sin< k Total no. H to 'k n<l/lln nu~ehe ~ legs tngsil, impinged YOY Total YOY Totn 1 Spotted gar 481 7.46 12.54 0 .24 0 .14 Skipgack herring 98,751 9.80 40. 18 37.11 9.05 Gizzard shad 343,312 8. 96 640.19 141-11 l. 97 Threndfin shad 1,909,'<92 1 ~ 565.04 1,565.04 4.49 4. 49 5 | |||
I<at p 1,134 NC 0-51 8. 19 Silver chub 6,509 8. 86 8. 86 2.71 2.71 Golden shiner 388 13.47 13.47 0. 11 O.ll Emerald shiner 2>200 6.71 6.71 1.21 1.21 Spotted sucker 3,178 422.81 475. 78 0.03 0.02 5 5 Blue catfish 2,476 NC NC 5 | |||
Blnck bullhead i>187 NC 0.28 15.61 Channel catfish 111435 5.46 22.89 7.71 l.84 Flathead catfish 1,050 9. 24 18,98 0.42 0.20 White hnss 13,408 4.76 5.22 10.37 9.46 Yellow buss 29<936 76.28 77.30 l. 45 1.43 Green sunfish 3,115 88.97 110.04 0.13 0.10 Bluegill 9,423 1,702.98 3,204.60 0.02 0.01 Lor<gear sunfish 452 508.81 1,203.31 <b.ol <0.01 Redear sunfish 2<561 396.99 483.97 0.02 0.02 Spotted bass 791 24.27 27.95 0.12 OvlO Largemouth bass 564 60.52 123.98 0.26 0.13 White crappie 4,996 2. 05 7.00 8.98 2. 63 Logperch 15690 468.06 468. 06 0. 01 0.01 Sauger 1,846 14.37 21. 08 0.47 0.32 Fresh<<ster drum 233,902 151.46 300.17 5.69 2.87 | |||
: 1. Refers to young-of-year fish. | |||
: 2. Refers to all ages collected in su<m<<er cove samples. | |||
3: Bused on a reservoir surface area of 27,150 ha. | |||
: 4. Not collected on cove rotenone samples. | |||
: 5. Calculation not possible. | |||
33 Table 8. I!><rim<It>~<I >>tu>><ll>>II >>r>>< k numb>>r>> (I>>>>><><I <>>> <<<>v>> r>><<>>>>>>>> ><>>mI>l>>>>) | |||
Io< ><<<l<'>'t> <I >>I>>'> I< >< of I I><h l>< Wh>><>l< r R<>>>>>rv>> lr I I'>II>) o>>>IIP>j<'qd MIIh Il>u I'III. | |||
u;<I l>m>I<<<l I>>I>>l Iml>l>>II< m<>>l <h>rl>>II Ihr I><'rl<><l I 8< I>I > ml>< r 1<II<>- II h>>II>>><I Mean standing Percent of Standing Total No. stock (No/ha) Stock Numbers Species Impinged Y Total YOY Total 2 Skipjack herring 110,487 30.67 75. 52 13.33 5.39 Gizzard shad 1,353,913 6,830.07 12,521.83 0.73 0.40 Threadfin shad 4,635,290 26,024.10 26>028.07 0.66 0. 66 Mooneye 656 5 5 NC NC Silver chub 7,537 96. 43 96.43 0.29 0.29 Golden shiner 5,522 39. 80 39.80 0.51 0.51 I | |||
Emerald shiner 8,003 63. 82 63.82 0.46 0.46 Bullhead minnow 1,230 436.22 436.22 0.01 0.01 Smallmouth buffalo 845 NC 38.66 5 0.08 Spotted sucker 7,395 12. 16 152.46 2.23 5 | |||
Blue catfish 2,562 NC 0. 26 36.29 Black bullhead 595 NC 5 5 NC Brown bullhead 1,778 NC NC Channel catfish 24,719 2. 89 67.40 31;50 1.35 Flathead catfish 2,217 13.37 19.20 0. 61 0.43 White bass 50,681 30. 16 33.56 6.19 '.56 Yellow bass 67>005 19.08 21. 06 12.93 11.72 Green sunfish 39,210 14.79 41.33 9.76 3.49 Bluegill 84,977 6,60?.19 8 '94.00 0.05 '.04 Longear sunfish 9,287 1,995.37 3,238.69 0.02 0. 01 Redear sunfish 27,625 227.18 443.92 0.45 0. 21 Largemouth bass 1,771 50.56 277.36 0.13 0.02 White crappie 6,780 0.40 2. 68 62.42 9.32 4 5 5 Black crappie 581 NC NC Logperch 1, 730 215. 58 215.58 0. 03 0,03 Sauger 2,535 ?.20 72.12 1.30 0.42 Freshwater drum 215,783 52.41 239.52 15.16 3.32 1, Refers to young-of-your fish. | |||
: 2. Refers to all ages collected in summer c<>v> samples. | |||
: 3. Based on a reservoir surface area of 27,]50 ha. | |||
: 4. Not collected on cove rotenone samples. | |||
: 5. Calculation not possible. | |||
34 Proportion of standing stock removed ranged from 5.39 percent of all ages in the third period to 29.38 percent in the first period and from 13.33 percent of youngmf-year alone in the third period to 45.97 percent Ln the first period (Tables 6 and 8). | |||
Gizzard shad Impingement of gizzard shad showed a distinct increase during the operational periods, exhibiting an order of magnitude increase in the third operational period over the first operational period. A similar increase in numerical standing stock was observed (Tables 6-8) for the three corresponding yearw of cove rotenone sampling. This increase in standing stock was also SE reflected in the 1977 cove samples after high impingement of the previous year's standing stock.'elatively few youngmf-year gizzard shad were collected in 1975 cove samples (Table 7) and higher than expected impingement of young-of-year occurred during this second period. Except for this case, the proportion of standing stock removed by impingement was between 0.41 percent and 1.97 percent. | |||
2'" | |||
Despite an order of magnitude increase in standing stock estimates of threadfin shad from 1974 to 1976, the impingement of threadfin shad was similar for the first and third periods, (4.55 and 4.64 million fish, respectivelyl Tables 6 and 8). During the second period, the impi'ngement of this species was reduced to approximately 1.9 million fish (Table 7). Maximum proportion of standing stock removed by impingement was 6.85 percent (during the first operational period). In 1977 the standing stock was reduced to an extremely iow level (Table 9). | |||
35 Table 9. Estimated standing stock numbers (based on cove rotenone samples) of selected species of fish in Wheeler Reservnir (1977}. | |||
3 Me n standin stock No/ha Spec ies YOY Total Skip)ack herring 30.2 33.2 Gizzard shad l0 ~ 434.4 15,615.3 Thre r>>lfln>>had /~ 1 fi. 0 4 4 Hooneye Silver chub 72.7 72. 7 Golden shiner 12.6 12.6 Emerald shiner .2 .2 Bullhead minnow 185.6 185. 6 | |||
" | |||
'Smallmouth buf falo 3.8 21.4 Spotted sucker 15.8 168.3 4 4 Blue catfish 4 4 Black bullhead 4 4 Brovn bullhead Channel catfish 15. 2 21. 2 Flathead catfish 10.9 16.5 White bass 63.3 66.4 Yellow bass 235.8 237.9 Green sunfish 72. 6 126.3 Bluegill 2,351.8 3,880.6 Longear sunfish 706.3 1,847.6 Redear sunfish 600.1 765.5 Largemouth bass 118.7 193.6 White crappie 2.1 88.8 4 4 Black crappie Logperch 573. 5 573.5 | |||
, Sauger 55. 4 60,0 Freshwater drum 199,7 348.1 | |||
: 1. Refers to young-of-year fish. | |||
: 2. Refers tn all ages collected in summer cove sample <<. ~ | |||
: 3. Based on reservoir surfact area nf 27,150 ha. | |||
: 4. Not collected in cove rotenone samples. | |||
Carp were impinged in relatively high, numbers only during the second period. The estimated 1,134 fish represented 8.19 percent of the estimated standing stock of this species in Wheeler Reservoir. | |||
,Silver chub Silver chub impingement remained essentially constant throughout | |||
~he three periods at levels not exceeding an estimated 9,000 individuals per year. The proportion of standing stock removed by impingement was least | |||
'ln the third period (0.29 percent). | |||
Channel catfish Channel catfish were impinged in similar numbers during the first and third operational periods. Numbers were lowest during the second period. | |||
Standing stock increased during the corresponding three years of rotenone sampling (Tables 6-8). | |||
The data suggest that a relatively high proportion of youngmf-year standing stock (59.68 percent, 7.71 percent, and 31.50 percent in 1974, 1975, and 1976, respectively) were impinged. Computations using standing stock numbers for all size classes combined resulted in a much lower proportion removed during these years (8.17 percent, l.84 percent, and 1.35 percent, iespect1vely; Tables 6-8) . | |||
White bass Tmpingement of white bass was over three times higher for the three-unit operational period than for the first and second operational periods. | |||
Standing stock numbers increased an order of magnitude from 1974 to 1976 I | |||
37 (Tables 6-8). As a result, the proportion of standing stock numbers of white bass in Wheeler Reservoir that were impinged decreased from the first to the third operational period. Overall, the proportion of standing stock numbers removed due to impingement ranged from 14;41 percent for young-of-year in 1974 to 6.19 percent in l976 and from 11.66 percent for all ages combined in 1974 to 5.56 percent in 1976. Despite the increaseg number impinged during the third period, standing stock of young-of-year and all ages combined of white base increased from 1976 to 1977 (Table 9). | |||
Yellow bass Impingement of yellow bass showed a marked increase over the three operational periods while mean numerical standing stock in Wheeler Reservoir tended to decrease during this period (Tables 6-8). Consequently, highest relative impingement occurred during the three-unit operational period. The proportion of standing stock reanved by impingement increased from about 1.5 percent during the first two periods to over ll percent during the third period (three-unit operation). Despite the high impingement during the three-unit operation, standing stock of young-of-year increased an order of magnitude | |||
, in 1977 (Table 9). | |||
Green sunfish Impingement of this species increased from 10,154 during the first period to 39,210 during the third operational period (Tables 6 and 8). Conversely, corresponding standing stock estimates decreased from tne first to the third period, resulting in the highest proportion of standing stock being impinged during the third period (9.76 percent of )uveniles and 3.49 percent of 1 | |||
all ages combined). The results of cove sampling in 1977 (Table 9), however, showed the greatest standing stock in this year. | |||
White cra ie Impingement of vhite crappie shoved a slight decrease during the three operational periods (numbers were lovest for the third operational period). Standing stock numbers of white crappie were relatively stable over the first three study years (Tables 6-8) and increased greatly in 1977. | |||
Low abundance of young-of-year vhite crappie in the 1976 samples resulted in the high relative impingement (62.42 percent of standing stock numbers) for this age during the three-unit operational period (Tables 6-8). Also, impingement vas high compared to estimated standing stock during the first phriod (27.71 percent of young-of-year and 13.86 percent of the total summer standing stock of all sixes). | |||
~Sau eL'mpingement of sauger ranged from approximately l,&00 fish in the second period to about 3,700 in the first period. Standing stock estimates increased considerably from the first to the third period (Tables 6-8). The proportion of total standing stock removed by impingement exceeded 1 percent only in the first period. | |||
Freshwater drum Impingement of freshvater drum vas highest during the second operational period when intake volume and number of screens in operation vaa least (Table 7). | |||
Standing stock estimates for both young-of-year and all ages combined reflected this unexpected outcome and vere greatest during this period (Table 7). Impinge-mept of freshwater drum appears to be a function of reservoir abundance. The highest relative impingement (Tables 6 and 8) of young-of-year drum vas in the third period (15.16 percent of standing stock numbers and in the first period | |||
39 for all ages combined (6.43 percent). Standing, stock was greatest in 1977 (Table 9) following the three years of impingement monitoring. | |||
DISCUSSION V | |||
The large number of species collected on the intake screens at Browne Ferry Nuclear Plant indicates that the intake is not particularly selective. Impingement probably represents a good qualitative picture of the fish community in wheeler Reservoir. This idea is supported in that species which were unique to either impingement or cove rotenone samples were uncommon | |||
(< 0.05 percent of the total number collected), Compared with the proportional composition of the rotenone samples, a relatively higher percentage of threadf in shad and skipjack herring were impinged on the intake screens. Sunfish species were impinged in proportions considerably less than those estimated by cove rotenone samples. Thus, the pelagic and highly mobile shad and herring seemed to be more susceptible to impingement than sedentary shoreline species such as the sunfish. It is recognised, however, that cove sampling probably over-estimates reservoir densities of sunfish and underestimates the more pelagic species. | |||
Impingement (all species combined) was lowest for the second operational period when intake flow was lowest and highest for the three>>unit operational period when volume intake of cooling water was greatest. Thus, overall there was a positive relationship'etween the level of plant operation and impingement. | |||
However, differences in impingement among operational periods for several of the dominant species (e.g.. spotted sucker, silver chub, white crappie, and sauger) did not appear to be related to pjant operation an<I may have rcfl<<ct<<d year class variation of these species in the reservoir. | |||
40 Several deviations from the "typical" seasonal pattern for monthly impingement of clupeids .occurred after the start of three-unit operation at Browns Ferry Nuclear Plant. The high fall impingement (approximately 4.5 million fish from September through November 1976) was probably due to a large standing stock of young-of-year clupeids in Wheeler Reservoir. High impingement in November may also reflect unusually high natural mortality of threadfin shad due to cold shock from exceptionally low water temperatures during 1976-1977 | |||
). | |||
(Fig ure 2). D ecreased impingement during December-February, with even colder water temperatures, suggests that this earlier natural mortality may have severely reduced the numbers of threadfin shad available for impingement. | |||
The failure of clupeid impingement as well as standing stock to increase to usual levels the following susaner suggests that exceptionally high natural mortality of 'fish the previous winter resulted in much reduced levels of recruitment during the spring. Thus, the low impingement of clupeids in late summer 1977 probably reflects low abundance of threadfin shad in Wheeler Reservoir. | |||
Higher impingement during the night may be the result of (1) diel changes in the distributions of these species in the reservoir (e.g., shoreward movement during the night) causing the fish to become more abundant in the intake area during nocturnal periods and/or (2) decreased ability to avoid the intake during the hours of darkness. it e erogene ty among replicates Excessive heteroge used to statistically examine the difference between een day ay an i i i a d n g h t impingement accentuates the highly variable and sporadic nature of impingement. This probably reflects the contagious distributional nature of these species in the reservoir. | |||
41 Impingement was fairly uniformly distributed among screens except during the one-unit operational period. High impingement on the end screen(s) is probably the result of higher density along the intake channel shoreline. During the one-unit period, the return channel from the cooling towers had not been excavated. A corner was created by the intake channel shoreline and left side (Unit 1 screens) of the intake pumping station. These results suggest that for three-unit operation of Browne Ferry Nuclear Plant, the distribution of fish in the intake channel probably had no significant effect on impingement differences among screens. | |||
For most species examined, the intake screens at Browne Ferry primarily impinged young~f-year fish larger than 51 mm in total length. Th' absence of smaller individuals probably is due to the size opening of the intake I | |||
screen. Smaller fish could be abundant in the intake but would pass through the screens and be entrained with the cooling water. The predominance of juvenile fish in impingement samples is probably a result of several factors: (1) the greater relative abundance of these age classes in the reservoir (e.g., the high impingement of clupeids during late suuaaer months is related to the high abundance of juveniles of this group in the reservoir}; (2) juvenile fish of some species may concentrate in shoreline areas and thus be relatively more susceptible to the intake at Browns Ferry Nuclear Plant; and (3) juveniles are il weaker swimmers than adults of the same species and thus are more likely to be impinged given similar exposure levels. | |||
For three dominant species (skipjack herring, channel catfish, and freshwater drum) which exhibited high impingement levels compared to estimated standing stock, relative as well as total impingement for the third period was less than or similar to that for the first period. This suggests that impingement | |||
42 at Srowns Ferry Nuclear Plant was not directly related to standing stock or intake water flow for these species. White base also showed lowest relative impingement during the third period despite increased total impingement. | |||
Standing stocks of this species increased over the four-year period (1974-1977}. | |||
Mhite crappie and yellow base showed higher relative impingement during the third than during the first operational period. The potential for adverse impact from impingement for white crappie appears to be minimized by the fact the estimated 12~nth impingement was actually slightly less for e three-unit than the one-unit operational period. The estimated impinge-ment for the three~nit operational period probably included fish from the abundant 1975 year class. Recruitment of white crappie in Wheeler Reservoir during 1976 was apparently very poor and resulted in high relative impingement for the corresponding operational period. | |||
Although impingement of yellow bass was highest during the three-unit operational period, the large increase in standing stock the following year suggests that impingement did not have an adverse impact on this species. | |||
Mopneye, blue catfish, and black bullhead were infrequently collected in cove rotenone samples; hence, it was difficult to assess the potential for adverse impact due to impingement. Since these species are routinely collected in other types of sampling and since estimated numbers impinged were small, the possibility of a deleterious effect to the reservoir population appears unlikely. | |||
Sunfish impingement increased approximately fourfold from the first tq the third operational period. Except for green sunfish, the standing stock estimates were much greater in 1976 than in 1974. The proportion standing stock r~ved by impingement was low (< 1 percent} for all periods. Expansion of | |||
43 cove densities of suqfish to reservoir density by che mechnd used here prnhnhly produces an overestimate of reservoir standing stock. However, it i8 experced that, except for green sunfish, adgusting the standing stock to only the productive areas of the reservoir vould show impingement co be lese than 1 percent of che standing stock. | |||
CONCLUSIONS | |||
'early all species in Mheeler Reservoir, excluding some darters And shiners, vere collected from the Browne Ferry Nuclear Plant intake screens ac least once since 1974. For the 42 species impinged at rates estimated co be one fish or less per day, the potential for an adverse impact is lov. None of these species is present in such low numbers that the removal of up to 365,fish per year would adversely affect their populati,ons. | |||
Thirteen of the remaining 30 species vere impinged at rates estimated to exceed one fish per day but in numbers vhich represent less than 1 percent of the estimated reservoir standing stock. hll of these species are common to che Tennessee Valley and, except for bluegill and redear sunfish, less than 1O,OOO fish per year of each species vere estimated to be impinged. For these species this level of impingement is not considered sufficient to cause an adverse impact to the respective populations in Mheeler Reservoir. Furthermore, although bluegill and redear sunfish vere impinged in high numbers, compared co the estimated standing stock this loss.(< O.l percent for bluegill.and < O.S percent for redear) appears to be negligible in terms of impact tn their populations. | |||
Five of the remaining 17 species vhich vere impinged at rates exceeding 1 percent of the estimated standing stock for at least. one 12-month period were | |||
44 rarely collected in cove samples. Because these species (mooneye, blue catfish, black and brovn bullhead, nnd black crappies) arc common in Tennessee Valley vaters and vere impinged at rate" estimated to be less than three individuals per day, impingement is not considrred to have the notential for adverse impact. | |||
The remaining lo species vere impinged in numbers exceeding 1 percent of their estimated standing stocks. Among these, ,tanding stock data for skipJack herring and gizzard shad did not reveal any effect of plant operation on their population levels in Wheeler Reservoir. For both species the proportion of standing . tock impinged vas least in thc third period vhen standing stock estimates vere highc. t.. At thc end of three years of'peration nnd monitoring, these populations do not appear to have been adver ely af'fected by the Brovns I'erry Plant. The much reduced standing stock of threadfin shad in 1977 reflects the effect of lov trmperature rnther than any effect of the intake. It, is cxnected that the rrcnvrry of this species vill be independent of plant operation. | |||
It. is very unlikely that the impingement of 1,134 carp per year vould pose an adverse impact to this population. Similarly, silver chub, a species commonly impinged throughout much 1 | |||
of the Tennessee Valley, vas collected in sufficiently lov numbers to preclude the poss5bility of an adverse impact to the Wheeler Reservoir population. | |||
Channel catfish densities are probably poorly estimated by cove rotenone sampling. This species appears to be more charncterist5.c of the main-stream portion nf the reservoirs. Standing .". ock numbers increased -through-cut the three years of monitoring and annual impingement did not increase appreciably from the fi.rst to the third operational period (maximum 25,000 .ishI, zherebv demonstrating thr absence of adverse impact. | |||
The increased impingement of ~hite bass from the first to the third period,may be due to both increased plant operation and increased abundance. | |||
The density of this fish is also probably underestimated by cove rotenone since it is a pelagic species more characteristic of the open reservoir, Since the standing stock of white bass increased from 1976 to 1977 despite impingement of 51,000 inuividuals of the 1976 standing stock, impingement of white bass does .not constitute an 'adverse impact. | |||
The Yellow bass population probably experienced no adverse impact from impingement. Although increasing impingement coupled with decreasing standing stock estimates during the monitoring period resulted in a maximum stock removal of 11.22 percent for all ages combined, the very high standing stock of young-of-year in 1977 probably precludes an adverse impact. | |||
Green sunfish showed a trend of increasing impingement and decreasing standing stock which resulted in greatest potential for impact during the third period of three-unit operation. However, neither the total number impinged nor the proportion of standing stock impinged is expected to adversely affect this population. The decreasing trend in green sunfish standing stocks was continuous from 1969 through 1976. Additionally, the increased standing stock in 1977 indicates that the impingement has not adversely affected this population. | |||
White crappie were probably greatly underestimated by cove sampli,ng. | White crappie were probably greatly underestimated by cove sampli,ng. | ||
The impingement of up to 8,000 individuals per year is not expected to represent an adverse impact to the Wheeler Reservoir white crappie population. | The impingement of up to 8,000 individuals per year is not expected to represent an adverse impact to the Wheeler Reservoir white crappie population. Similarly, the removal of up to 3,700 sauger per year is not expected to adversely affect the reservoir population. | ||
Similarly, the removal of up to 3,700 sauger per year is not expected to adversely affect the reservoir population. | Freshwater drum impingement appears to be more related to standing stock than to the level of plant operation. Since the proportion of drum stocks | ||
Freshwater drum impingement appears to be more related to standing stock than to the level of plant operation. | |||
Since the proportion of drum stocks 46 removed by impingement and the annual impingement has not increased through-out tho years ol plant operation, the posslbtllty of an ndverso fmpact ls unl ike1y.In suaaaary, the overall impingement of fish at Brogans Ferry Nuclear Plant does not appear to represent an adverse environmental impact to the Wheeler Reserv~r f.'ah community. | 46 removed by impingement and the annual impingement has not increased through-out tho years ol plant operation, the posslbtllty of an ndverso fmpact ls unl ike1y. | ||
47 IeITERATURP CITED Hollander, H., and D.A.%olfe.1973.Nonparametric statistical methods.John Nley and.";ons, Inc.503 pp.Sokal, R.R., and P.S.hohlf.1969.3iometry.M.H.Preeman and Company, San Francisco, California. | In suaaaary, the overall impingement of fish at Brogans Ferry Nuclear Plant does not appear to represent an adverse environmental impact to the Wheeler Reserv ~r f.'ah community. | ||
776 pp. | |||
47 IeITERATURP CITED Hollander, H., and D. A. %olfe. 1973. Nonparametric statistical methods. John Nley and .";ons, Inc. 503 pp. | |||
Sokal, R. R., and P. S. hohlf. 1969. 3iometry. M. H. Preeman and Company, San Francisco, California. 776 pp. | |||
e}} | e}} |
Revision as of 02:03, 22 October 2019
ML18024A718 | |
Person / Time | |
---|---|
Site: | Browns Ferry |
Issue date: | 03/01/1979 |
From: | Gillelend J TENNESSEE VALLEY AUTHORITY |
To: | Harold Denton Office of Nuclear Reactor Regulation |
References | |
TVA-BFNP-TS-122, NUDOCS 7903120303 | |
Download: ML18024A718 (111) | |
Text
ENCLOSURE 1
PROPOSED CHANGES TO UNIT 1 TECHNICAL SPECIFICATIONS APPENDIX A
t SAFETf L.l LMIT Fuel Claddin Inta rit LIHITINC SAPETT 2.1 Fuel Claddin I
SYSTRH SETTING Inta rit Core eptay and U'CI > 378 in.
actuation
~
teactot above vebbe lou uatet level sero J. HPCI end RCIC > 470 iri.
ac'tuation reactor above vebbe'I Icnr water level sero Ko H4fn bteaQL isola > 470 in.
tion valve cloeure above veebel reactor lou vater sero level
TABLE a+1~B REACTOR PROTECTION SYSTEM (SCRAM) INSTRUMENT CALIBRATION MINDCUM CALIBRATION FREQUENCIES FOR REACTOR PROTECTION INSTRUMENT CHANNELS Instrument Channel Group (1) Calibration Minimum Frequency (2)
IRM High Flax Cccaparison to APRM on Control- Bate (4) led Shutdowns (6)
APRM High Flux Output Signal ~ B Heat Balance Once every 7 days Flew Bias signal B Calibrate Floe Bias Signal (7) Once/operating cycle B TIP System Traverse (8) Every 1000 Effective Full Pcerer Hours High Reactor Pressure Standard Pressure Source Prexy 3 Months High Dryvell Pressure Standard Pressure Source Every 3 Months Pressure Standard Evezy 3 Months
. High Rater Level in Scram Discharge Volame h Note (5) Note (5)
Turbine Ccadeaser Lcm Vacuum h standard Vacuum Source 5
Every 3 Months I
Main Steam Line Imlation Valve Closure h Note (5) R)te (5)
)Cain Steam Liae High Radiatioa B Standard Cuxrent Source (3) Every 3 Months Turbine First stage. Pzessare permissive h Standard Pressure Source Every 6 Months Turbiae contxol valve - Loss of oil pressure h Standard Pressure Source ChaceIoperating cycle Tarhine Stop Valve Closure Note (5) Note (5)
NOTES FOR TABLE 4'.l.B 1, A description of three groups is included in the bases of this specif ication.
- 2. Calibrations are noc rcquiied when the systems aze not required to be operable or are tripped. If calibracions arc missed> they shall be performed prior co returning the syste'm to an operable status.
- 3. The current source provides an instrument channel alignment. Cali-bration using a radiation source shall be made each refueling outage.
4~ Haximum frequency required is once per week.
Physical inspection and actuation of these position, svitches vill be performed once per operating cycle.
6, On controlled shutdowns> overlap between the IRM's and APRM's will be verified.
- 7. The Flow Bias Signal Calibration will consist of calibrating the sensors, flow convcrters, and signal offset necwotks during each operating cycle. The instrumentation is an analog type with redun-dant flov signals that can be compared. The flow compazacoz trip and upscale will be functionally tested according to Table 4,2.C to ensuze the proper operating during the operating cycle. Refer to C'.1 Bases for further explanation of calibration frequency.
- 8. A complete tip system traverse calibrates the LPRH signals to the process computer. Tke individual LPRN meter readings vill be adjusted as a minimum at the beginning of each operating cvcle before reaching 100% pover.
The frequriicy of r.il ilirntion of tli< /'<pgN F1<iv Bfn <inx .'l< twnrh ha<i been i <<t<<hi I </lii'<l a!i i ach rcf<<i. if<<<; ui<r.<g<;. Tlii.r<. <<t>>:;. v< i:il I<<<.t rumenc'<
whfch must be col fbrat>>d anil fr wf ll take aevi ral hn<<r<< to perform the calibration of ch>> enr.fre network. Whfle the calfbratfon is being per-formed, a acro flow signal will bi-. sent ro half o! the 'O'g'l's resulting in a half scram <ind rod block condf.r,ion. Thus, if the calibration were perforned during operation, flux shaping would not be possible. 'Based on experience ac other gcncracing scatfons, drift of instruments, such as those fn ci<c Flow Biasing Hecwork, fr not sfgiiiEicant and therefore, to avoid spurfous scrams, s calibr ~ tfon frequency of each refueling out-age is es ablfshcd.
Croup (C) devices arc 'act fve,only durfr<g a gfven port fon oE che opera-tional cycle. For example, chc It:.'! is active during certup and inactive
~
during full-power oper-cfon. Thus, chc only tcsc char. fa aeanfngful thc one performed gust prior ro shutdown or startup', i.c., the tests that are perforned gust prior to use of the instrument.
Calfbracfnn frvq<<>>ncy of thc in<icrumcnt chnnicl i~ divided into two groups. These are as folio~a:
- l. F ssive type indfcatfng devfces chat can be co~pared with like units on a continuous basis.
- 2. Vacuum tube or semiconductor devices an>quat>> aargfa. Vor the Apg'f system drf ft of clcctronic apparatus fs not:he only considera-tion fn determining a calibration frequency. Ch.ngu .n power distribu-tion and loss of chac<ber sensftivity dictate a calibration every seven days. Calfbrar ion on this frequency assures plant operation at or below thermal if~its.'
coaparfson of Tables'4.1.A and 4.1.6 indicates that two instr~ant channels have not been included fn thc latter cable. These are: code switch in shutdow<i and cianual scram. All of the devices or sensors associated wfch these scram functions arc sf ~pie on-off switches and.
hence,,calfbratfon during operation fs noc sppl'cable, f.e., the swfcch f,'s either on or off.
The ratio of Core Maximum Fraction of Limiting Power Density (MFLPD) to Fraction of Rated Power (FRP) shall be checked out once per day to determine if the.APRM scram requires ad)ustment. This will normally be done by checking the APED readings. Only a small number of control rods are moved daily 47
~ ~ ~
4~1 BASF.S during steady-state,opera'tion"and thus the .ratio is not expected to change significantly.
The sensitivity of LPRM detectors decreases with exposure to'eutron flux at a slow and approximately constant rate. The APR'I system, which uses the LPRM readings to detect a change in thermal power, will be calibrated every seven'days using a heat balance to compensate for this change in sensi:tivity. The RBM system uses the LPRM reading to detect a localized change in thermal power. It applies a correction factor based on the APRM output signal to determine the percent thermal gower and therefore any change in LPRM sensitivity is comoensated for'y the APRM calibration. The technical specification limits of CHFLPD, CPF.,
MAPLIIGR and R ratio are determined by the use of the orocess computer or other backup methods. These methods use LPR'.! readings and TIP data to determine the power distribution.
Compensation in the process computer for changes in LPRH sensitivity will be made by performing a full core Tip traverse to uodate the computer'alculated LPRH correction f"ctors every 1000 effective full
' power hours.
As a minimum the individual LPRH meter readings will be adjusted at the beginning of each operating cycle prior to reaching 100 percent oower.
'
'[nti CAiMO LT KOi<S FOR OPEPuXT iO,'4 .SURVRiLLAhCF. RE UIRQK!iTS 3 3 K Control Rods 4 3 8 l'oncrol Rods 4, Control rods shall noc be Mhen required, Cha presence withdrawn for starcup or of ~ second 1iceasel refueling unless ac least operates'o verify the followiag ot cuo.source range channels the correct rod prograa shally have an observed count race be verified equal to or greater chan
~
thrae counts per second'. 4. Prior co control rod vithdraMal for acarcup or during refueling, 5..During opcracion Mich verify chac at lease tMo source 1 i<<icing cont ra 1 rod pa c- 'ange channels have ao observed.
carns, as dccermined by the counc race of at least three designated qualified person- counts per second. C nel, either:
- a. Noth R8H channels shall 5. Mhen a limiting control rod be operable: pattern exists, an insceceant or functional test of the RN shall be performed prior to b~ Control rod vichdraMal vichdraval of the designated shall be blocked. rod(s) and at least, once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> thereafter.
C. Scram Insertion Times 1.After each -refueling outage all operable rods shall be scram time~
tested from the fully vithdrawn position vith the nuclear system pressure above 800 psig This Insertion Times testing shall be co<<pleted prior to C. Scram exceeding 40X pover. Belov 20X l, The average scram insertion pover, only. rods in those sequences Cine, baaed on the deenergi- (A12 and A34 .or B12 and B ) vhich zacion of the scran pilot valve vere fully withdrawn in th$ region aolenoids as tire zero, of all from 100X rod density to 50X rod operable control rods in the density shall be scram time tested.
reactor power opera c ion condi The sequence restraints imposed upon Cion shall bc no greater than: the control rods in the 100-50 percent rod density groups to the X Xnsortad Froo Avg. Scram Inser- preset pover level may be removed Full Mithdrcun tion Tines sec by use of the individual bypass switches associated vith those .
5 0.375 control rods vhich are fully or 20 0,90 partially vithdravn and are not 50 2.0 vithin the 100-50 percent rod density 90 3. 500 groups. In order to bypass a rod, the actual rod axial position must be knovn; and the rod <<ust be in the correct in-sequence position.
124
a' Whsga~
'a 0
Unit 1 l,wIviir. Cn~nivlnns Fnli sprat TIOU SURVFII.LaÃCF RE~UIM ~FMTS 3.7.C Secondary Containment 4.I.c Secondar Containment
- 1. Sc condnry containment intc; .1 ~
I Secondary containment surveil-durity shall be maintained in lance shall be perfoaaed as the reactor aonc" at all times indicated helot:
except as apccf(iud in 3.7.C.2.
240
lP t
%14t 'I 0
4 ~ 7.C Seconisr I Containment
- a. Secondary containment capa-bility tomaintaim 1/4 inch o vater vacuum under calm Mtn'
+ 5 mph) conditions Mith s system inleafcage tate o f not more than 12,000 cfm, shall be demonstrated at each refueling outage prior to refueling.
- 2. If reactor zone secondary con-1
- 2. After a secondary containment tainment integrity cannot be violation is determined the maintained the folloving con- standby gas treatment system ditions shall be met: vill be operated inanedisteiy after the affected zones are isolated from the remainder of
- a. The reactor shall bc made the secondary containment to aubcrit ical and Specif ica- confirm its abil'y to main<<
tion 3.3,A shall be mer.. tain the remainder of the secondary containment at 1/4-
- b. The reactor shall be cooled inch of Mater negative prcssure dovn beloM 212'F and the under calm Mind conditions.
reactor coolant system vented.
c; Fuel movemcnt shall not bc permitted in the reac-tor zone.
- d. Primary containment 'ntegri:y ma inta i ned .
3, Secondary containment integrity shall be mslntnlned in the re-fueling zone, except as speci-fied in 3.).C.4.
24)
0 PROPOSED CHANGE TO UNIT' TECHNICAL SPECIPICATIONS APPENDIX B
Monitoring vill be perfors:e6 usinu standard accepted scnpling procc."urea vhich arc on fil'e in the office of'he Division of Forestry, Fisherics, and Hildlife Development, Norris, Tennessee.
Re ortins Recuirencnt The results vill be smaaarized annually in the annual reports of the nonradiological environnental monitoring program.
Baaas proportion of the river flow vill be routed through the plant f'rsignificant A
cooling purposes, and during periods when larval fish ar'e abundan
'for there is the potcrtial entraicuaent of large numbers of fisbes.
The specified study will deteraine the numbers of fish crgs and larva entrained in the cooler"., vater system resulting frow pl.nt operation and identify the need for possible corrective action.
(f) Fish inoin enent on Intake Screens (Delete) was f
\
s",
\
PROPOSED CHANGES TO UNIT 2 TECHNICAL SPECIFICATIONS
SAFETY LIHIT LIHITINC SAFETY SYSTEH SEITING A.l" tuel Claddin Int>> rit 2il Fuel Claddin Inta rit I ~ Core epray and LFCI ~ 378 in.
actuation reactor above vestee lou water level cero J. HPCI and RCIC ~ 470 in.
actuation reactor above vesset le vater level cero K. Main ateam ieola<<> 470 in.
tion valve cloeure above veeeef reactor lou eater cero level
TABLE 4alaB REACTOR PROTECTION SYSTEN (SCRAN) INSTRUNKNT CALIBRATION NININUN CALIBRATION FREQQE!CIES FOR REACTOR PROTECTION INSTRUNZNT CHANNELS Instruaent Channel Group (I) Calibration Nininum Frequency (2)
IRN High Flux Caaparison to APRN on Control- Note (4) led Shutdowns (6)
APRN High Flux Output Signal ~ B Heat Balance Oace every 7 days Flow Bias Signal B Calibrate Flow Bias Signal (7) Once/operating cycle LPRN Signal TIP System Traverse (8) Every 1000 Effective Full Power Hours High Reactor Pzessure Standard Pressure Source Every 3 Nonths High Drywall Pressure Standard Pressure Source Every 3 Nonths Reactor Low Mater Level Pressure Standard Every 3 Nonths High heater Level in Scraa Discharge Volam Hots (5) Note (5)
Tarbine Ccadeaser Low Vacuua Standard Vacuua Source Every 3 Ncaths I
Naia Steaa Line Isolation Valve Closure Note (5) Note (5)
Naia Stean Line High Radiati.oa Standard Current Source (3) Every 3 Noaths Turbine First Stage Pressure
. Pernissive Standard Pressure Source Evezy 5 Ncaths Turhiae Coatrol Valve - Loss of Oil Pressure A Standard Pressure Source Csee/operating cycle Turbine stop valve closure Note (5) Note (5)
NOTFS FOR TABLE 4.1.1 A description of three groups's included in the bases of this speciEication.
- 2. Calibrations are not required when the systems are not required to be operable or are tripped. If calibrations arc missed, they shall be performed prior to returning the system to an operable status.
3, The current source provides an instrument channel alignment. Cali-bration using a radiation source shall be made each refueling outage.
4~ Haximum frequency required is once per week.
Physical inspection and actuation of these poiition switches vill be performed once per operating cycle.
5~ On controlled shutdowns> overlap between the IRM's and APRH's will be verified.
- 7. The Flov Bias Signal Calibration vill consist of calibrating the sensors, flow convcrters, and signal offset networks during each operating cycle. The instrumentation is an analog type vith redun-dant flov signals that can be compared. The flow comparato" trip and upscale vill be functionally tasted according to Table 4,2,C to ensure the proper operating during the operating cycle. ReEer'o 4'.1 Bases for Eurther explanation of calibration frequency.
- 8. '
complete tip system traverse calibrates the LPRH signals to the
~
process computer. The individual LPRN meter readincs vill be ad)usted as a minimum at the beginning of each operating cvcle before reaching 100% power.
'.t<<tMork ha>> been Th<< freque>>cy o5 r.>11hrnt ion of t'l>> Assed Fl<>M Bin >lax
<<!> <<<<ch refuel in;; uut <<g<<. There <<rc <<.~v> r!>1 1n<<trumrnts a at<<hit<<had Mhich must be ca11hrat<<d and it M111 takr. acv<<r<<1 hnur<< to perform the is being per-calibration of the entire nctuoA. While the calibration formed, a aero EloM signal will b<<sent to half of the >'ZRH's resulting in s half scram and rod block condition. Th>>s, if the calibration Mere performed during operation, flux shaping uould not be possible. Based on cxper'fence at other generating stations, drift oE in truments, such aa those in the Flov Biasing Hetuork, ir not significant and therefore, to avoid spurio>>s scrams, a cal.ibr tion frequency of each refueling out-age is establ ishcd.
Croup (C) devices are active only durin" a given portion oE the opera-tional cycle. For example, the 1g.'! is active during startup and inactive during full-pover oper" tion. Thus> thc only test that is meaningful thc one performed gust prior to ehutdoun or startup, 'i.c., the tests that are performed gust prior to use of the instrument.
Calibrntion frequency of thc in<<trumcnt chan >cl 1e divided into tvo groups. These are as folloMe:
- 1. P ssive type indicating devices that can be comp-red vith like units on a continuous basis.
- 2. Vacuum tube or semiconductor devices and detectors that drift oz lose sensitivity.
Experience vith passiv" type instruments in generating stations and oub-stations indicates that the specified calibrations are adequate. For those devices which employ amplifiers, etc., drift specifications call for driEt to be less than 0.4X/month; i.e., in the period of a month a d> ift of . 47 Mould occur acd thus providing for adequate margin. Por the APR.'1 system d. 1Et of electronic apparatus i<<not:he only considera-tion in determining a calibration frequency, Change in power distribu-tion and loss of chamber sensitivity dictate a calibration every seven days. Calibration on this frequency assures plant operation at or belov thermal limits.
A comparison of Tables 4.1.A and 4.1.B indicates that two instrument channels have not been included in thc latter table. These are: mode sMitch in shutdown> and manual scram. All of the devices or sensors associated vi th these scram funct ions are s imp le on-o. f svitches and, hence, calibration during operation is not sppl'cable, i.e., the switch ie either on or off.
The ratio of Core Maximum Fraction of Limiting Pover Density (MFLPD) to Fraction of Rated Power (FRP) shall be checked out once per day to determine if'he APRM scram requires adJustment. This will normally be done by checking the APRM readings. Only a small number of control rods are moved daily 47
4~1 BASFS durYng steady-state operation and thus the ratio is not expected:. to change significantly.
The sensitivity of LPRM detectors decreases with exposure to neutron flux at a slow and approximately constant rate. The APR'I system, which uses the LPBM readings to detect a change in thermal vower, will be calibrated every seven days using a heat balance to compensate For this change in sensitivity. The RBM system uses the LPRM reading to detect a localized change in thermal power. It applies a correction factor based on the APRM output signal to determine the percent thermal oower and therefore any change in LPWI sensitivity is comoensated for by the APRH calibration. The technical specification limits of CHFLPD, CPF.,
MAPLIIGR and R ratio are determined by the use of the orocess computer or other backup methods. These methods use LPR.'! readings and TIP data to determine the power distribution.
Compensation in the process computer for changes in LPRM sensitivity will be made by performing a full core Tip traverse to uodate the computer'alculated LPRM correction f-ctors every 1000 effective full power. hours.
As a minimum the individual LPRM meter readings will be ad)usted at the beginning of each operating cycle prior to reaching 100 percent power.
L IInc covnLYKovs Foa opERXTtov SURVr.lLLANCF. RE UIRKY. 'HIS 4.3.8 Contxol Rods 4~ Control rods shall noc be vithdraMn for ecarcup or When required, the preaaaca refueling'nless at least of ~ ascoad 1icaaaad operator cMo.source range channels to verify ths followtog ot have an observed count the correct rod program shalL to or grcacer chan rate,'qual be verified.
~
three counts pcr accond'. 4. Prior co control rod withdravsl for scaxcup or during refueling, 5.,During. operation Mich verify thac ac lease tvo source lcaxns, imi ting control rod pa c-ns determined by che
'ange channels have ao observed count rate of ac least three designated qualif icd persou- counts per second.
nel, either:
a, Both RBtl channila shall 5. When a limiting control rod ba. opcrablc: pattern exists, an lnstrLxssat
'or functional teat of the lQA shall be pcrfoamcd prior to b Control rod wichdraval withdrawal of the designated shall be blocked. rod(s) and ac least once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> chereaftar.
C. Scram Insertion Times 1.After each refueling outage all operable,,rods shall be scram time tested from the fully withdrawn position with the nuclear system pressure above gOO psig This C. Scram Insertion Times testing shall be completed prior to exceeding 40X power. Below 20X power', only. rods in those sequences
- l. The average scraDI inecL'cion (A12 and A34 .or B12 and B ) which Cima, baaed on the dccnergl-zacion of the scram pilot valve were fully withdrawn in tlat region colcnotds as time zero, of all from 100X rod density to 50X rod operable control rods in che density shall be scram time tested.
reactor power oparacion condi The sequence restraints imposed 'upon tion shall be no greater chan: the control rods, in the 100-50 percent rod density groups to the X Inserted Prom Avg. Scram Inser- preset power level may be removed Full With raMn by uee of the individual bypass switches associated with those 5 0.375 control rods which are fully or 20 0.90 pnrtially withdrawn and are not 50 2.0 within the 100-50 percent rod density 90 3. 500 groups. In order to bypass a rod, the actual rod axial position must bi known,'nd the rod aust be in the correct in-sequence position.
124
7 Al 1~~4@
Wi'
Unit 2
>.shnrif: Cn~nlvin.iS Fnii nrrar71OU SURVF1LLhÃCF RK'iIU1v ~FNTS 3.7,C Secondary Containment
- l. Sc condnry containment inte- 1. Secondary containment surveil-grity shall bc maintained ln lance shall be performed as the reactor tone at all times indicated helot:
except as ~pcclfled ln 3.7.C.2.
240
3oloC
~ ~ Secondar Containment 4.7.C Scconiar i Containment
- a. Secondary containment capa-bility tomaintafa 1/0 inch o vater vacuum under cain uin"
(< 5 mph) condition uitlt a system inleakage rate oi not more than 12,PPP cf>,
shall bc demonstrated at each reive Ling outage pr io r to refueling.
- 2. If reactor zone secondary con<< 2~ AEter a secondary containment tainment integrity cannot be violation is determined thc maintained the folloving con- standby gas treatmenr. system ditions shall be met: vill be operated innediately after the affected zones are isolated from the remainder of
- a. The reactor shall be made the secondary contai'nment to subcritical and Specifica- confirm its ability to ma in-tion 3. 3. A shall be me t . tain the remainder of the secondary containment at 1/4-
- b. The reactor shall be cooled inch of uatcr negative prcssure doun belou 212'F and the under calm vind conditions.
reactor coolant system vented.
c; Foci movemcnt shall not be permitted in the reac-tor xone.
d." primary containment integri:y maintained.
Secondary containment integrity shall be ma)ntnlneJ in the re-fueling zone, except as'peci-fied in 3.7.'C.4.
241
PROPOSED CHANGE TO UNIT 2 TECHNICAL SPECIFICATIONS APPENDIX B
0 Honitoring vill be perfonre6 usinu standard accepted scnpling procc".urea
,vhich arc on file in the office of the Divi ion o. Forestry, Fisheries, and Mildlife Development, Norris, Tennessee, Re ortinr Recuirencnt The results vill be su~arized annually'n the annual reports of the nonradiological environmental monitoring program.
Ba"ea A significant proportion of the river flov vill be routed through the plant for cooling pu~nscs, end during periods vh n la> val fish axe abundant there is the potential 'for entrairmcnt of large numbers of fisbes.
The specified stuQ'ill detercLine the nv~bers of fish cr,.".s and lerva entrained in the cool>v", vater system resulting frow pl.at operation and identig the need for po" sible corrective action.
(f) Fish i@pin enent on Intake Screens (Delete)
PROPOSED CHANGES 'TO UNIT 3 TECHNICAL SPECIFICATIONS
SAFETY L IllIT LIMITING SAFETY SYSTEM SETTING 1.1 .FUEL CLADDING INTEGRITY 2 1 FUEL Cl ADDTNG INTEGRITY D. Shutdown Condition C. scram and isola- 2 538 in tion reactor above Whenever the reactor is in low water vessel the shut'down condition level zero
, with irradia ted fuel in the reactor vessel, the D. Scram--turbine 10 per-water level shall not be stop valve cent valve less than 17.7 in. above closure closure the top of the normal active fuel zone. E. Scram- - turbine control valve Fa st closure--Upon trip of the fast acting solenoid valves 2~ Loss of con- 550 psif trol oil
'p.".es sure Scram--low con>> I 23 inches denser vacuum Hg vacuUAl G. Scram--main S 10 per-steam line cent valve isolation closure H. Main steam isola- < 825 psig tion valve closure
--nuclear system )
low pressure Core spray and h 378 in.
LPCI actuation-- above
'reactor low water vessel l.evel zero HPCI and RCIC 070 in.
actuation--reac- above tor low water vessel level zexo K. Hain steam isola- 070 in.
tion valve above closure--reactor vessel low water level zero ~
13
TABLE 4+1 ~ B REACTOR PROTECTION SYSTEM (SCRAN) INSTROHENT CALIBRATION HIHIKOH CALIBRATIOH PREQUE1CIES FOR REACTOR PROTECTION INSTRUMENT CHANNELS Instrument Channel Group (1) Calibration Hinimum Frequency (2)
IRK High Flux Caaparison to APRlC on Control- Note (4) led Shutdcwns (6)
APRH High Flux Output Signal ~ B Heat Balance Once every 7 days Flar Bias Signal B Calibrate Flnr Bias Signal (7) Once/operating cycle LPRH Signal ~
B TIP System Traverse (8) Every 1000 Effective Full Poser Hours High Reactor Pressure Standard Pressure Source Srery 3 Honths High Drywall Pressure Standard Pressure Source Ee'ezy 3 Honths Reactor tuw Hater Level Pressure Standard Evezy 3 Honths High Hater Level in Sczam Discharge Vol~ Note (5) ~e (5)
~ Turbine Condenser Lov Vacuum Standard Vacuum Source Every 3 lamths I
Hain Steam Line Isolation Valve Closure Note (5) Mte (5}
Hain Steam Line High Radiation B Standard Current Source (3) Every 3 Nouths Turbine First Stage Pressure Permissive h Standard Pressure Source Every 6 Honths Turbine Control Valve - Loss of Oil pressure h Standard Pressure Source &ace/operating cycle Hots (5) Note (5)
NOTf S FOR TABLE 4 . 1. 8 lo A description of three groups is included in the bases of this specif ication.
- 2. Calibrations arc not required when the systems azc not required to be operable or are tripped. If calibrations arc missed, they shall be performed prior to returning the system to an operable status.
3, The current source provides an instrument channel alignment. Cali-bration using a radiation source shall be made each refueling outage.
4~ Haximum frequency required is once per Meek.
- 5. Physical inspecfion and actuation of these position switches will be performed once per operating cycle.
6~ On controlled shutdowns > overlap between the IRM' and APRM' wil1 be verified.
- 7. The Flow Bias Signal Calibration will consist of calibrating the sensors, flow convcrters, and signal offset networks during each operating cycle. The instrumentation is an analog type with redun-dant flow signals that can be compared. The flow comparator trip and upscale will be functionally tested according to Table 4.2..C to ensure the proper operating during the operating cycle . Refer to C'.1 Bases for further 'explanation of calibration~ frequency.
- 8. A complete tip system traverse calibrates the LPRH signals to the process computer. The individual LPRM meter readines will be adjusted as a minimum at the beginning of each operating cvcle before reaching 100K power.
$0
The frequency of calibration of the APRN Flow Biasing Network has been established as each refueling outage. There are several i,nstruments which must be calibrated and it will take several hours to perform the calibration of the entire netw'ork. awhile the calihration is beinq performed, a zero flow signal will be sent to half of the APRH's resultinq in a half scram and rod block condition. Thu's, if the calibration were performed during operati'on, flux shaping would not be possible. Based on experience at other qenerating stations, drift of instruments, such as those in the Flow Biasing Network, is not significant and therefore, to avoid spurious scrams a cal'ibration frequency of each refueling outage is established.
Group (C) devices are active only during a given portion of the operational cycle. For example, the IRM is active during startup and inactive during full-power operation. Thus, the only test that is meaningful is the one performed gust prior to shutdown or startup; i.e., the tests that are performed gust prior to use of the instrument.
Calibration frequency of the instrument channel is divided into two groups. These are as followss
- 1. Passive type indicating devices that can be compared with
'like units on a continuous basis.
2~ vacuum tube or semiconductor devices and detectors that drift or lose sensitivity.
Experience with passive type instruments in generating stations and substations indicates that thespecified calibrations are adequate. For those devices which employ amplifiers, etc. ~ drift specifications call for drift to be less than 0.4%/month; i.e.,
in the period of a month a drift of .4% would occur and thus providing for adequate margin. For the APRM system drift of electronic apparatus is not the only consideration in determining a calibration frequency. Change in power distribution.and loss of chamber sensitivity dictate a calibration every seven days.
Calibration on this frequency assures plant operation at or below thermal limits.
A comparison of Table 4.1.A and 4.1 B indicates that two
~
instrument channels have not been included in the latter table.
These are: mode switch in shutdown and manual scram. A11 of the devices or sensors associated with these scram functions are simple on-off switches and, hence, calibration during operation is not applicable, i.e., the switch is either on or off.
The ratio of Core Maximum Fraction of Limiting Power Density (CMFLPD) to Fraction of Bated Po~er (FRP) shall be'checked out once per day to determine if the APRM scram requires ad)ustment. his will normally be done by checking the APRH readings.
Only a small number of control rods are moved daily during steady>>state operation and thus the ratio is not expected to change signi.icantly, 46
'r The sensitivity of LPBM detectors decreases with exposure to neutron flux at a slow and approximately constant rate. The APRM system, which uses the LPRM readings to detect a change in thermal power, will be calibrated eVery seven days using a heat balance to compensate'for this
'change in sensitivity. The RBM'system uses the LPRM reading to detect a localized change in thermal power. It applies a correction factor based on the APRM output signal to determine the percent thermal oower and therefore any change in LPRM sensitivity is compensated for by the APRM calibration. The technical specification limits of CNFLPD, CPF.,
MAPLIIGR and R ratio are determined by the use of the process computer or other backup methods. These methods use LPR"! readings and TIP data to determine the power distribution.
Compensation in the process computer for changes in LPRM sensitivity will be made by performing a full core'Tip traverse to uodate the computer'alculated LPRM correction factors every lOW effective full power h'ours.
As a minimum the individual LPRM meter readings will be ad]usted at the beginning of each operating cycle prior to reaching 100 percent power.
\
LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS 3~ 3 CTIVITY CONTROL I ~ 3 REACTIVITY CONTROL C. Scram Insertion Times C. Scram Insertion Times
- 1. The average scram l. After each refueling outage all insertion time, based operable rods shall be scram time on the deenergization tested from the fully withdrawn of the scram pilot inoperable position with the nuclear system valve solenoids,as pressure above 800 psig time zero, of all control rods This in the reactor power testing shall be completed prior operation condition to exceeding 40$ power. Below shall be no greater 20$ power, only rods in those A than: ~
sequences (A12 and A34 or B12 and B34) which were fully with-
% Inserted From Avg. Scram Inser- drawn in the region from 100$
rod density to 504 rod density shall be scram time tested. The 5 0. 375 sequence restraints imposed 20 0. 90 upon the control rods in the 50 2~0 100-50 percent rod density groups 90 3 ' to the preset power level may
- 2. The average of the be removed by use of the indi-scram insertion times vidual bypass switches associdted for the three fastest with those control rods which operable control rods are fully ot partially withdrawn of all groups of four and are not within the 100-50
~
control rods in a percent rod density groups. Xn two-by-two array order to bypass a rod, the shall be 'no greater actual rod axial position. must than: be known; and the rod must be in
% Inserted From Avg. Scram Inser- the correct in-sequence position, 5 0~ 398
- 2. At 16 week intervals, 10$ of the 20 0. 950 operab'e control tod drives 50 2 120 shall be scram timed above 90 3. 800 800 psig. ttlhenever such scram time measurements are made, an
- 3. The maximum scram evaluation shall be made to insertion time for. provide reasonable assurance 90% insertion of any that proper control rod drive operable control rod performance is being shall not exceed F 00 .
maintained.
seconds.
- 6~ 128
Unit 3 LIHITZNG COVDZTIGNS FOR OPERATZO>i SURVEZLLAHCE REqUZREMZNTS 3e7 COW'AX%i..NT S STEM,S 4e 7 CONGA.XN!-'.P.NT SYSTEMS C'e Secondar Containment Co Secondar I Containment 0 Secondary ccntainment I
~ 1~ Secondary containment integrity shall be surveys,llance shall be maintained in the 'erformed as reactor zone at all indicated belo~:
times erce"t as specified in 3.7.C.2.
~ LIMITINC CONDITIONS FOR OPERATION SgRVQILLANCE REQUIRENENTS 3~ 7 COhTA ANENT SYSTEMS 4 7 OtZM NHKNT S ST MS Secondary containment capability to maintain 1/4 inch of water vacuum under calm wind (<5 mph) conditions >
vith a system inleakage rate of not more than 12 F 000 cfm, shall be
'emcnstrated at each refueling outage prior to refuelinq.
- 2. If reactor. zone 2. After a seccndary secondary containment containment vio1ation integrity cannot be is determined the maintained the standby gas treatment following conditions shall be met:
'system vill be operated in mediately after the affected
- a. The reactor . zones are isolated shall be made from the remainder of subcritical and the secondary Speci fication containment to 3.3.h shall be confirm its agility mete to maintain the
- b. The reactor remainder of the shall be cooled secondary containment down belov 2124F at 1/4-inch of water and the reactor negative pressure coolant system under calm vind vented. conditions.
c~ Fuel movement shall not be permitted in the reactor zone.
- d. Primary con ta inment integrity
'aintained.
4 PROPOSED CHANGE TO UNIT 3 TECHNICAL SPECIFICATIONS APPENDIX B
-17 Monitoring uill be performed usinu standard accepted smpling procc".urea vhich arc on file in the office,of the Division of Forestry, Fisheries, and Mildli.e Development, Norris, Tennessee.
. Re ortinr Becuiremcnt The rerults vill be su~ari:zed annually in the annual reports of the nonradiological environmental monitoring program.
Baoes A significant proportion of the river floe vill be routed through the plant for cooling purposes, end during perioas when larval fish are abundan there is the potential 'for entrainment of large nunbers of'ishes.
The specified study vill determine the numbers of fish cr,.".s and larvae entrained in the cooler "~ eater systen resulting from pl .at operation and identiQ tt:e need for po"sible corrective action.
(f) Fish imnin enent on Xntake Screens (Delete)
ENCLOSURE 2 REASONS AND JUSTIFICATIONS FOR PROPOSED CHANGES TO BROWNS PERRY NUCLEAR PLANT UNITS 1, 2, AND 3 TECHNICAL SPECIFICATIONS UNIT 1 A endix A Page ll, Sections,2.1. J add 2.1.K:
Proposed changes to these setpoints from +490 inches to 4470 inches. This was omitted in an amendment approved by NRC on August 2, 1978, concerning low water level setpoints.
Pages 40, 41, 47, and 48:
These proposed changes consist of adding an explanatory note to Table 4.1.B, changing LPRM to APRM in 4.1 Bases, and changing 4.1 Bases for clarification of LPRM-APRM requirements. The purpose of these changes is to correct previous typographical errors and to clarify calibration requirements.
Page 124, Section 4.3.C.l:
The proposed change allows post refuel outage control rod drive scram timing to be conducted in parallel with the vessel hydrostatic leak test, thus saving about one day in the startup test sequence. The reduction in required test pressure from 9SO psig to 800 psig is conservative in that the scram performance (insert speed) generally decreases accordingly. As can be seen from the attached figure (Attachment 1) which specifies a maximum-minimum scram performance band, the scram time change is insignificant over the desired pressure reduction. The data presented in the attached figure is only applicable to single CRD scrams with charging valve closed or full reactor scram with changing valve open. Scram time is the time from lode og voltage to scram air pilot valves to 90 percent insertion. This data was obtained from General Electric startup test procedures which is a part of the Browns-Ferry RTI5.
~Aendix A continued Pages 240, 241:
Proposed to delete section 4.7.C.la from the technical.
specifications and to reletter the remaining paragraph from b to a. This specification is no longer applicable to Browlls Perry as all preoperational tests are completed and the requirement to test secondary containment integrity once per cycle is specified in 4.7.C-lb to become 4.7.C-la.
~Aenddx B Page 17: See Attachment 2 UHXB 2
~Aendix A Page ll, 'Sections 2.1.J and 2.1.K:
Same as unit 1 above Pages 40, 41, 47, and 48:
Same as unit 1 above Page 124, Section 4.3.C.1:
Same as unit 1 above Pages 240, 241:
Same as unit 1 above
~Aendix B Page 17: See Attachment 2
UNIT 3
~Aendix A Page 13, Sections 2.1eJ and 2.1.K:
Same as page 11 for unit 1 above Page 39, 40, 46, and 47:
Same as pages 40, 41, 47, and 48 for unit 1 above Page 128, Section 4.3.C.l:
Same as page 124 for unit 1 above Pages 251,'52:
Same as pages 240, 241 for unit 1 above
~Aendix B Page 17: See Attachment 2
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ATTACHMENT 2
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JUSTXFICATIOH POR PROPOSED ETS CHANGE The attached report vas submitted to EPA on February 13, 1978, as a portion of TVA's 316(b) demonstration. The assessment of the effect of impingement of fish on the intake screens at Browns Perry Nuclear Plant provides the )ustif5cation for the proposed technical specification change.
In sununary, the assessment concludes that impingement on the Brows Perry intake has no significant adverse effect on the fisheries resource of Wheeler Reservoir.
EFFECTS OF IMPINGEHENT AT BROWNS FERRY NUCLEAR PLANT ON THE POPULATIONS OP PISH IN WHEELER RESERVOIR January 1978 Division of Forestry, Fisheries, and Wildlife Development Fisheries and Waterfowl Resources Branch
INTRODWCTrnN The Browne Ferry Nuclear Plant is TVA's largest aperatlng steam sle>>I rl< llenor¹l lng pl>>bi, h~vlnll ¹ threr>>>>IL d¹¹lgn c¹pni'lly of j,456 megawatts (MW). The plant l,s located on the north bank of Wheeler Reservoir in north central Alabama at Tennessee River Mile 294.4. Initial criticality of units 1, 2, and 3 vere as follows: unit 1-August 16, 1973, unit 2-July 20, 1974, and unit 3>>August 8, 1976. Between March 27, 1975, and August 31, 1976, no electricity was produced due to an outage caused by a fire.
During this time a reduced flov of water was pumped through the cooling water intake.
Impingement monitoring vas continued uninterrupted from February 1974 through December 1977. It is currently being continued as part of the require-ments of the operating license issued by the Nuclear Regulatory Commission and in accordance vith the format described in the environmental technical specifications for Brovns Ferry.
Descri tion of the Coolin Water Intake and Pum in Station The cooling water intake at Browne Ferry consists of a shoreline skimmer wall, an intake channel, a cooling vater return channel, and a concrete pumping station located at the end of the intake channel (Figure 1). Water passes through three openings in the skimmer wall. Each opening is 12.2 m wide and 7.3 m deep. The tops of the openings are located 3 m below normal maximum pool elevation.
The intake channel is 150 m long from the skimmer vali to the pumping station. At normal maximum pool the water depth slang a 6.1 m vide area in the middle of the channel is 10.1 m. From there the sides of the channel slope at a 3:1 ratio. Directly in front of the pumping station the bottom slopes dawn
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an additional 1.5 m to the bottom of the intake opening, resulting in a maximum depth of 11.6 m at the intake screen at normal maximum pool.
The cooling tower return channel enters the left side (facing the I
pumping station) of the intake channel (Figure 1). Pish movement up the cooling tower return channel is precluded by a concrete wall located several hundred meters upstream from the intake channel.
The 70.7 m long pumping station contains nine cooling water circulator pumps (three per unit) and 18 vertical traveling screens. Each pump 'contributes
-1 13.9 m 3 sec for a total three-unit condenser and auxiliary demand of 124.9 m 3 sec -1 (1.98 million gallons per minute).
Each of the endless-belt vertical traveling screens is housed in I a .
separate intake screen well measuring 2.6 m wide (inside dimensions). The trashrack opening for each intake well measures 1.6 m wide by 7.3 m high. The screen panels are 2.3 m wide and support a square mesh steel screen having 9.5 mm (3/8") openings. At 9.8 m of water depth in the intake well, each 3 -1 screen is designed to piss 6.9 m sec (110,000 gpm) through a clean surface at
-1 a velocity of 61.0 cm sec (2.0 fps). The screens are cleaned either on a regular basis (such as shift changes or daily) or after a maximum pressure differential develops across the screens due to clogging. The long impingement time for fish in addition to exposure to the high pressure spray system during the cleaning process results in essentially 100 percent mortality of impinged fish.
METHODS Two procedures for estimating impingement were used during the monitoring period. From March 1974 through July 1976 the following method was employed: expansion factors were calculated every two months (or less)
for each screen by counting from each screen in use all fish impinged during four consecutive 12-hour (day/night) periods. An expansion factor for each screen vas calculated simply by dividing the total fish for all screens by the total for each screen. These expansion factors vere employed in subsequent impingement counts to estimate total impingement on all screens from a count of fish from one test screen. Three times per week all fish impinged on the test screen (or alternate screen) vere counted. To estimate 'the total impinge-ment for all screens, the expansion factor for that screen vas multiplied by the number of each species impinged on the test screen. If one or more pumps were not in operation, a correction formula vas used to adjust the total estimated number impinged. Revision'-of the environmental technical specifications in September 1976 changed these impingement monitoring procedures. Coincident vith the startup of Unit 3, this revision required a direct count o! fish from each screen during one 24-hour period each veek.
Test Procedures Twenty-four hours prior to each impingement count, all screens vere simultaneously rotated and vashed to remove impinged trash and fish. The screens were then stopped for a 24-hour test period. The test screen (in early tests) or each screen in operation (in later tests) vas 'vashed individually after, the 24-hour test period. The fish vere collected in a large basket at the end of the screen wash water sluice conduit. These fish vere then sorted into species by 25 mm total length increments. The number and total veight (gm) for each size class vere recorded for each species. When excessive fish precluded a direct count of all fish, subsampling within species was conducted. All impinged fish, including those impinged during sampling days as I veil as during days of routine screen cleaning, vere deposited in a sanitary landf'ill.
Cooli Mater Intake Velocities Intake ~ster velocities were measured on May 18, 1977, during operation of all nine condenser circulating pumps. The average velocity through the three skimmer wall openings was 29.6 cm sec 1, 28.0 cm sec 1 and 32.0 cm "ec" . Overall, individual measurements ranged from 7.0 to 50.0 cm sec -1 . The mean cross section intake channel velocity 100 m upstream of the pumping station was 38.4 cm sec . Velocities ranged from 27.0 to 48.0 cm sec
-1 . Seventy-five velocity measurements taken 1 m in front of the 18 trashracks averaged 36.6 cm sec and ranged from 18.0 to 50.0 cm sec 1.
Numerical Anal sis For analyzing and comparing the impingement data, three distinct 12-month periods were identified. These are based on the level of plant operation. The first operational period extended from March 27, 1974, shortly after impingement monitoring was initiated, until March 27, 1975, when fire interrupted plant operation. This period included Unit 1 operation from March 27, 1974-August 27, 1974, and Units 1 and 2 operation from August 28, 1974-March 27, 1975. The average number of pumps in use on the sampling days was 4.6.
The second period included the first 12 months of no electric generation following the fire. During this time a reduced water flow was pumped through the intake. The average number of pumps in use was 2.4.
The third operational period represented the first 12 months of normal operation after the fire. During this period all three units were
placed in operation, with an average of 7.2 pumps in operation. on sampling days ~
An estimate of total impingement for these three 12~nth periods was obtained by calculating averages of daily (24-hour) impingement as determined by either of the two procedures described above. Average daily estimates for each species were then multiplied by the number of days
.in each period.
Differences in total observed impingement (all speciea combined) between intake screens were examined for each level of plant operation using the Kruskal-Wallis procedure (Hollander and Wolfe 1973). Only those samples in which counts were obtained from all screens (6, 12, or 18 for 1 e 2 ~ or 3 unit operation, respectively) were used in the statistical procedure. Multiple comparisons of impingement by sc'reen were made using a nonparametric procedure based on Kruskal-Wallis ranks (Hollander and Wolfe 1973). All test statistics were examined for significance at the a 0.05 level. These data were also examined graphically by plotting the pooled proportion impinged on each screen for each operational period.
'I Differences between day (0600-1800 hours) and night (1800-0600 hours) impingement were examined for each species for which total observed impingement (all day/night test periods combined) was equal to or greater than 1,000 individuals. A replicated goodness-of-fit procedure using the G statistic (an alternative statistic of the more common X ) was used to test the null hypothesis 2'hat the proportion impinged during the day was equal (0.50) to impingement during the night (Sokal and Rohlf 1969). Test statistics were examined for significance at the a 0.05 level. For each species examined, the pooled proportion impinged during the day and night periods was presented graphically.
/
Size distribution of impinged fish was examined for: skipjack herring, gizzard shad, threadfin shad, channel catfish, white bass, yellow bass, green sunfish, bluegill, redear sunfish, white crappie, sauger, and freshwater drum. For each of the 12 species, a frequency histogram (percentage) of length class was prepared summarizing all available size information collected from March 1974 to August 1977.
The determination of possible adverse impact by impingement was facilitated by the comparison of estimated 12-month impingement for selected species with numerical standing stock information for the same species derived from cove rotenone data. Within each operational period, those species were selected which showed estimated 12-month impingement ~ 365 (one individual per day). For each operational period, standing stock information for corre-sponding summer months was expanded to a total number for Wheeler Reservoir.
This total number was calculated by multiplying the mean number per hectare by the total surface area of the reservoir. For each species, this expansion was performed separately for both young-of-year (based on length class) and all I
size classes combined. Estimated number impinged for each species was then divided by total and young-of-year standing stock estimates for Wheeler Reservoir, resulting in an estimated proportion (expressed as percent) for each length class removed by impingement (referred to as relative impingement in this report) at the intake of Browns Ferry Nuclear Plant. This method of estimating impact on reservoir populations has one primary limitation--the assumption that for each species in question, cove rotenone data accurately estimate reservoir standing stock.
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12 species were <:ol.lected (Table l). During summer cove samples taken in 1974-i977, 60 species" were collected from a total of 15 cove-samples collected in Wheeler Reservoir. Of the species collected from the intake screens, four represented 95.8 percent of the total'observed impingement. These were threadfin shad (76.5 percent), gizzard shad (12.3 percent), freshwater drum (4.3 percent), skip)ack herring (2.7 percent) and were the only species which individually represented more than 1 percent of the total observed impingement.
In cove samples nine species each exceeded 1 percent of the total numerical standing stock for all three years combined: threadfin shad (37.1 percent),
gizzard shad (28.0 percent), bluegill (16.8 percent), longear sunfish (6.4 percent), redear sunfish (1.6 percent), bullhead minnow (1.4 percent), logperch (1.4 percent), warmouth (1.3 percent), and freshwater drum (1.0 percent). None of the species impinged is currently classified as "threatened" or "endangered."
Estimated Total I in ement During the first operational period, March 27, 1974-March 26, 1975, an estimated 5.26 million fish of 50 species were impinged (Table 2). Four species (skipgack herring, gizzard shad, threadfin shad, and freshwater drum) comprised 97.7 percent of the total. Thirteen additional species exceeded an estimated 1,000 individuals impinged during the 12-month period including silver chub, emerald shiner, spotted sucker, blue catfish, channel catfish, white bass, yellow bass, green sunfish, bluegill, redear sunfish, white crappie, logperch, and sauger.
During the 12 months which followed the fire at Browne Ferry (second operational period), the total estimated number impinged dropped from the
Table l. Species list and percent of total for all fish collected from the Browne Ferry intake screens during the monitoring period March 1974-August 1977 and all species collected in 15 cove rotenone samples collected in Wheeler Reservoir in 1974N 1975, 1976, and 1977.
Percent, Percent Composition Composition Common Name Scientific Name (Impinged)
(Cove)'hestnut lamprey <0. 01 NC Paddlefioh, ~Pol odon ~sschula <0. Ol NC Spotted gar ~Le isoeteus oculatus <0. Ol 0. 02 Longnose gar ~Le isosteus osseus <0. Ol <O. 01 Shortnose gar ~Le isosteus platostomus <0. 01 NC Skipjack herring 2. 72 0. 16 Gizzard shad Deepsome ~ce edianum 12. 30 27.95 Threadfin shad Doroooms Hetenenss 76.49 37.08 Rainbov trout Helmo Helrdnari <0.01 NC Mooneye Hiodon ~ter isus 0. 01 NC Grass pickerel Esox americanus vermiculatus <0. 01 NC Chafn pickerel Rv<ix ~i, sr <0. 01 NC Stoneroller ~Cem ostoma enema'lum <0. 01 0,01 Goldfish Carassius auratus <0. 01 NC Carp ~trdnus ~car io 0. 02 0.01 Speckled chub ~mbo sis aesciualis <0. Ol NC Silver chub ~mba sie storerisna 0.23 0.27 River chub Nocomis ~micro o an 0.01 NC Golden shiner ~Notami onus ~cr soleucss 0. 04 O.OS L" a
Emerald shiner. ~Nocto is athetinoides 0.12 0.10 t Ghost shiner ~motto is buchenani 0.01 NC Common shiner ~Nocto is cornutus NI" 0. 01 Striped shiner NI <0. Ol shiner 'osyface
~Notxo ia rubellus <0.01 NC Spotfin shiner ~Nocto is ~silo cerus <0.01 0. 02
10 Table 1. (Continued)
Percent Percent Composition Composition Common Name Scientific Name (Impinged) (Cove)
M;;min shiner ~Notre is vhlucellus <0.01 0.04 Steelcolor shiner ~Notre ie ~vhi le1 NI 0. 01 Bluntnose minnow ~Pine hales notatue NI NG Fathead minnow . ~PIns hales Hronelas < 0.01 <O. 01 Bullhead minnow ~Pine hales ~vt 1lsx 0. 02 1.38 Blacknose dace ~Rhtnichth s atratulus <<0.01 NC Longnose dace ~Rhtnichth s cetaractae < 0.01 River carpsucker ~Car iodee ~car io < 0.01 <0.01 quillback ~Car iodes ~crtuus <0.01 NC Highfin carpsucker ~Csr iodes veliier NC Northern hogsucker ~Henteliun ~ni ricans <0. 01 <0.01 Smallmouth buffalo Ictiobus bubalus t
- 0. 01 0.09 Bigmouth buffalo Ictiohue ~crknellus <<0.01 <0.01 Black buffalo Ictiobus ~ni er <0. 01 <0. 01 /
Spotted sucker ~MIn treaa ~nelson s 0. 07 0.92 Silver redhorse Moxostoma anisurum < 0.01 0.02 River redhorse Moxostoma carinatum <0.01 <0.01 Shorthead redhorse < 0.01 <0.01 Black redhorse Moxostocn ~du uesnei <0.01 <0. Ol, Golden redhorse Moxostona errthrurnn < 0.01 0.11 Blue catfish Ictalurus furcatus 0. 08 <0.01 Black bullhead Ictalurus melas 0.02 <0.01 Yellow bullhead Ictalurus natalis <0.01 NC Brown bullhead Ictalurus nebulosus 0.01 NC Channel, catfish Ictalurua punctatus 0.39 0.13 Slender madtom Noturus exilie <0. 01 v
Flathead catfish ~Plodtctie olivarie 0.03 0.05 Blackstripe topminnow Fundulus notatus NI 0.02 Blackspotted topminnow Fundulus olivace<<s < 0.01 0.11 Mosquitofish Gambusia affinis < 0.01 0.03 Brook silverside Labidesthes sicculus < 0.01 0. 10
Table I, (Continuod)
Porcnnt Prrr~ nt Composition Composition Common Name Scientific Name (Impinged) (Cove)
White bass Morone chrh~eo e 0.55 0. 12 Yellow bass Morone ctaste~st 'anais 0.92 0.3&
Striped base Horonc onxatIl In <0.01 NC Rock bass Am~bio Platen r~u>>strip <0.01 <0.01 Redbreast sunfish ~ta osis naritus < 0.01 HC Green sunfish ~te o is ~ccnellus 0.33 0.40 Wnrmouth- ~Le o ta guineas 0. Ol 1.29 Orangespotted sunfish ~Le oats huetlls <0.01 0.20 Blue'ill ~Le oats aacrouhirus 0.72 16.78 Longenr sunfish L~eoels a~enlatts 0. 08 6s37 Redenr sunfish I~eomis micro o~hue 1 0. 24 1.84 Spotted sunfish ~Le oats punctntue < 0.01 NC Smnllmouth bass Mt~era terus dolanieut <0. 01 0.21 Spotted bees ~Mtcro rerun Munctulatus 0. 01 0. 16 Largemouth bass Micro terus ealaoides 0. 02 0.60 White crappie Pomoxlo nnnulnris 0.11 0.11 Blnck rrnppi>> Pomox to n t~romnculntus 0.01 r0.01 Fantail darter 8th>>ootomn flnbellave NI 0.04 Stripetnil darter Etheootomn kennicotti NI 0.12 Redline darter Htheostoma rufilineatum NI <Oe01 Yellow perch Perca flavescene NI <0. 01 Logperch Perctrs ~ca rodes 0.04 1. 39 Dusky darter Porc lna eciera < 0.01 <0;01 River darter Perr.lna ohumnrdi < 0.01 0. 03 Souger Stizootedion canadense 0.05 0.13 Walleye St izoo ted ion vi treum vit reum < 0.01 NC Freshwater drum A~lodtnotus Mrunuteca 4.34 I '.02 I., Not collected in rotenone nnmplrdd.
Not observed in impingement snmplee'.
LL Table 2 Estimated total number of all fish impinged at Browne Ferry Nuclear Plant between March 27, 1974-March 26, 1975 Total Estimated Number 'Total Eat (mated Impinged i' Number lmpf nged TLxb 150 Samples Lamprey 10 24 Chestnut lamprey 5 Psddlefish 69 168 Spotted gar 66 160 Longnose gar 27 Shortnose gar 5 Skipgack herring 90,807 220,964 Gizzard shad 75,440 183,571 Thresdfin shad 1,824,188 4>438,857 Dol'osoela sp 48,937 119,080 Mooneye 179 437 Goldfish 91 221 Carp 85 207 Silver chub 3,553 8,646 Golden shiner 271 660 Emerald shiner 1>269 3>OSS Bluntnose minnow 2 5 Fathead minnow 22 53 River csrpsucker 3 7 Quillback 5 12 Smallmouth buffalo 105 255 Bigmouth buffalo ,
Spotted sucker 431 1,049 Redhorse sucker 6 14 Catfish 2 Blue catfish 1>641 3,993 Black bullhead 366 892 Yell'ow bullhead 14 33 Brown bullhead 1 2 Channel catfish 8>924 21,716 Flathead catfish 209 508
Table 2~ (Continued)
Total Estimated Number Impinged In Total Estimated Taxa 150 samples Number Impinged Nosquitofish 6 14 White bass 5,805 14,126 Yellov bass 5, 940 14;453 Striped bass 21 51 Rock bass Redbreast sunfish 3 Green sunfish 4,173 10,154 Warmouth 160 390 Orangespotted sunfish 57 Bluegill 7,214 17 .556 Longear sunfish ~
150 366 Redear sunfish 3,250 7,910 Smallmouth bass 10 25 Spotted bass 24 59 Largemouth bass 136 332 White crappie 3,216 7,826 Black crappie 27 67 Logperch 927 2,256 Darter 1 2 Sauger 1,516 3> 690 Walleye 16 39 Preshwater drum 73 766 179 501 Total 2>163 >098 5,263,546
14 preceding period to 2.69 million fish of 52 species (Table 3). The three clupeids (gizzard shad, threadfin shad, and skip)ack herring) and !reshvatsr drum comprised 9&.2 percent of all fish collected. Seventeen additional species that exceeded an estimated 1,000 individuals for the 12-month period were carp, silver chub, emerald shiner, ghost shiner, spotted sucker, blue catfish, black bullhead, channel catfish, flathead catfish, vhite bass, yellov bass, green sunfish, bluegill, redear sunfish, vhite crappie, logperch, and sauger.
During the third operational period of three-unit operation, (September 1, 1976<<August 31, 1977) an estimated 6.67 million fish representing 61 species vere impinged (Table 4). During this period, the three clupeids and freshvater drum were again dominant and comprised 94.6 percent of the total, vhile 19 additional speciea vere each estimated to have been impinged in total numbers exceeding 1,000 each. These species vere silver chub, golden shiner, emerald shiner, bullhead minnow, spotted sucker, blue catfish, brovn bullhead, channel catfish, flathead catfish, vhite base, yellov bass, green sunfish, bluegill, longear sunfish, redear sunfish, largemouth bass, vhite crappie, logperch, and sauger.
P Estimated total weight of each species impinged was also calculated.
for samples collected during the third operational period (Table 4). Total weight estimated for all fish impinged during this period vas 63 metric tons.
Seasonal Patterns of Im in ament Figure 2 depicts the total impingement estimated by month for the period March 1974-August 1977. Clupeids showed a consistent pattern of lowest impingement in May or June. Impingement vas usually highest from December through March. An exception was 1976-1977 when clupeid impingement peaked during September-October.
15 Table 3 . Estimated total number of all fish impinged at Brovns Perry Nuclear Plant betveen March 27, 1975-March 26, 1976.
Total Estimated Number Impinged . In Total Estimated Taxa 152 samples Number Impinged Lamprey 23 Paddlefish 15 Spotted gar 481 Longnose gar 21 Shortnose gar 13 31 Skip)ack herring 41,011 98,751 Gizzard shad 142,578 343,312 Threadfin shad 793,013 1,909,492 Mooneye 144 346 Grass pickerel Goldfish 17 Carp 471 14134 Silver chub 2,703 64509 River chub 2 6 Golden shiner 161 388 Ps~sss s sp.
Cmefdid shiner 922 2,200 Ghost shiner 608 1,464 Spotfin shiner 20 Bluntnose minnov 11 Pathead minnov 13 32 Bullhead minnov 303 730 Blacknose dace 5 ll River carpsucker ll 25 illback 2 4 Smallmouth buffalo 332 800 Bigmouth buffalo 16 Black buffalo Spotted sucker 1,320 3,178 Redhorse sucker 47 114
16 Table 3 . (Continued).
Total gstimated Number Impinged In Total Estimated Taxa 152 samples Number Impinged Blue catfish 1,029 2,476 Black bullhead 493 1 ~ 187 Yellow bullhead 54 129 Brown bullhead 15 Channel catfish 4,749 11,435 Flathead catfish 436 1,050 White bass 5,569 j3,408 Y~llw hs<S I$ ,n')s Green sunfish 1 ~ 294 3oll5 Warmouth 103 248 Orangespotted sunfish 19 Bluegill 3,913 9 '23 Longear sunfish 188 452 Redear sunfish 1,064 2 '61 Smallmouth bass 3 8 Spotted bass 328 791 Largemouth bass 234 564 White crappie 2,075 4,996 Black crappie 15 37 Logperch 702 1,690 Barter 5 Sauger 767 1,846 Freshwater drum 97,140 2331902 Total 1,116,545 2e688e498
Table 4 ~ Estimated t.ot al numb@i and Meight of all fish species impinged at Srowns Perry Nuclear Plant between September 1976-August 1977. Estimates are ba'sed on 54 24-hour samples collected at one-Meek intervals.
Total Est. Number Total Wt. (kg)
Taxa Impinged In 54 sam lea Impinged In 54 aam les Total Pst. No.
Ttmfn6ad ~leTotal Est. Wt.(kg) ingate lamprey 12 0.61 81 4.10 'hestnut Paddlefish 0. 21 14 1.45 Spotted gsr 19 10.93 128 73. 85 Longnose gar 0.85 5.73 Shortnose gar 4.94 74 33.38 Skipgack herring 16,346 171.35 110,487 1,158.23 Gixenr<l Hhad 200,305 4,235.89 1,353.913 28,631.50 Threadfin shad 68'>,769 2,189.22 4.635,290 14,797.49 Mooneye 97 15.95 656 107.78 Chnin pickerel l. 36 14 9. 21 Stoneroller .03 0.20 Goldfish 36 8. 83 243 59. 66 Carp 10 5.03 68 34.00 Speckled chub 0. 08 27 n. 5>
Silver chub l,115 24.42 7,537 )65.07 Hfver chub 0.)2 0.72 Golden shiner 817 16.83 5,522 113. 78 Emerald shiner 1,184 7.84 8,003 53.01 Ghost shiner 10 0.02 68 0.16 Mimic shiner 33 0,06 223 0. 41 Bullhead minnow 182 1. 90 1,230 12.82 Longnose dace 0. 01 0.05 Quillback 0. 11 74 0.75 Northern hog sucker 0 '4 14 3. 63 Smallmourh buffalo 125 48. 95 845 330.86 Bigmouth buffalo 2. 24 34 15.13 Spotted sucker 1,094, 69.33 7,395 468.61 Silver redhorse 15 5. 94 101 40.16 Shorthead redhorse 0.60 4.04 Black redhorse 2.11 37 14.27 Golden redhorse 19 8.22 128 55.55
18 Table 4. (Continued)
Total Est.Number Total Est. Wt.(kg) Total Est.No. Total Est.Wt.(kg)
Impinged In Impinged In Impinged Impinged Taxs 54 samples 54 samples Blue catfish 379 33.79 2,562 228.40 Black bullhead 88 1.80 595 12.15 Yellow bullhead 0. 08 7 0.55 Brown bullhead 263 16.01 1>778 108.18 Channel catfish 3,657 175.22 24,719 1>184.36 Flathead catfish 328 9.91 2,217 67.01 Black Spotted topminnow <0. 01 7 0. 01 Brook silverside <0.01 20 0. 03 Rnite bass 7,498 131.19 50,681 886.71 Yellow bass 9>913 234.08 67,005 1,582.21 Striped bass 30 2.26 203 15. 26, Rock bass 0. 04 14 0. 30 Green sunfish 5,801 40 ~ 54 39,210 274.05 Warmouth 58 1.26 392 8.51 Orangespotted sunfish 0. 03 14 0.20 Bluegill sunfish 12,572 285.70 84,977 1,931.13 Longear sunfish 1,374 10.68 9,287 72.18 Redear sunfish 4,087 184.93 27,625 1,249.96 Spotted sunfish 1 0.04 7 0.25-Smallmouth bass 47 2.80 318 18.93 Spotted bass 50 l. 53 338 10.
Largemouth bass 262 17.42 1>771 36'17.75 White crappie 1,003 23.04 6,780 155.75 Black grapple 86 4.69 581 31.69 Logperch 256 l. 70 1,730 11.49 Dusky darter 7 0. 03 47 0. 22 River darter 0.02 27 0. 12 Sauges,' 375 52. 74 2,535 356.48 Walleye 3 2.45 20 16.53 Freshwater drum 31 924 1 322.38 215 783 8 >38.31 987,310 9,390.88 6>673>488 63,485.19
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~0 WOO SOb M A M J J A S 0 N D J F Month 7d Figure 2. Total estimated monthly impingement at Browne Perry Nuclear Plant for Clupeids (shad) and all remaining taxa during the period March 1974-August 1977. A geometric scale vas required to shou the large range in monthly values
'l 20
+38p$ 00 Clllpold All other togo 6it+00 '
409/00 \ ~G 204/00 0 102/00 I
O'QOO 26@00 C
"
12POO I
I.
h CL I
O ~00 C
'0 QOO E
~4 N
4+00 800 100 M A M J J A S 0 H 0 J l'onth
,14 Figure 2. (Continued)
~ All elhi ~ lIRI St I+00 I 409/00 dS 204/00 ',
A, 10+00 I I
SHOO 26Jt00
\
\ 0 o 12@00 E
00 C
'0 00 E
+00
) l 11 j
$ 00 400
' " J 4 S 0 N 0 J F Month Figure 2 (Continued)
22 fp88r400 QCtopota All other taxo StaP00 400/00 204gl00 to&00 5+00 25/00 C
E taP00 CL
~00 C
D
)I 3/00 E
Ol
~00 600 400 M A M J Month Figure ~ (Cont:inued)
23 Lowest impingement of clupeids during May-June was followed by a sharp increase in July and August for the first three years of record. This probably refl'ects the appearance of young-of-year. However, the pattern did not hold for the last year of data. Numbers remained low through August, the last month reported. Monitoring not reported here showed that threadfin shed impingement did not increase through December 1977. The impingement of low numbers of clupeids after June 1977 is likely associated with a very low'ensity of young-of-year I
threadfin shad in Wheeler Reservoir. Nonshad taxa showed a pattern of generally irregular fluctuations in monthly impingement between 6,000-60,000 fish (Figure 2).
Highest impingement often occurred in March with the highest value in March 1977.
Co arison of Da and Ni ht Im in ament Species selected for detailed examination of day versus night fmpfngemenf, were: skip)ack herring, gissard shad, threadfin shad, silver chub, emerald shiner, spotted sucker, channel catfish, white bass, yellow base, green sunfish, bluegill, longear sunfish, redear sunfish, white crappie, and freshwater drum.
The replicated goodness-of-fit procedure indicated significant departure from the null hypothesis (impingement during the day impingement during the night) for all 15 species (Table 5). For two species, green sunfish and longear sunfish, pooled G-values were not significant even though total G-values were significant.
Thus, if all replicates for these two species were treated as one observation, we would accept the null hypothesis stated above. Much of the variability in t'e analyses was accounted for by heterogeneity among the replicates. Thus, .
differences between.day and night impingement ware not consistent between replicates for all species treated.
The data in Figure 3 show that for all but one species (longear su<<tish) the pooled proportion of fish impinged during night was greater than during daylight.
24 Table 5. Results of replicated goodness-of-fit analyses comparing day and night impingement for 15 selected species. The G-value labeled "Het."
represents the statistic to test the hypothesis that all replicates were homogeneous, i.e., ware drawn from the same population. This value was calculated as the difference; Total G-value - Pooled G-value Hetero-gelleity G value ~
Number G-Values Species Day Night Total Pooled Het.
Skip)ack herring 81624 24,533 14,306. 7* 7o957 ~ 0* 6,349.7*
Gizzard shad 9,943 14,171 21025. 7* 745.2e 1,280.5*
Threadfin shad 96,563 181,917 62,308.3* 26,586.8* 35,721.5*
Silver chub 502 1I 053 314.8* 199.5* 115.3*
Emerald shiner 180 426 185.1* 102.8* 82.3*
Spotted sucker 18 42 39.8* 9 '* 30oO+
Channel catfish 589 858 193.8* 50. 3* 143.5*
White bass 266 991 647.0* 445.1* 201.9*
Yellow bass 65,9 11216 358.2* 168oO* 190.2*
Green sunfish 99 56.9* 3.5 53.5*
127'531 Bluegill 858 205.3* 77 ~ 7* 127.6*
Longear sunfish 42 34 36.5* 0.8 35.6*
Redear sunfish 70 169 125.1* 42.3* 82.8*
White crappie 145 335 168.8* 77.3+ 91. 5" 5'fn~ftosfct Atua 6,08 3 I t>,829 3,864.3< 1,349.9* 2, '514.
level of confidence.
4<'Statistically significant at the a ~ 0.05
2>
Percent
.2 2 .$ 0 .75 sqo SkipJack herring Gizzard shad Day 1$ 5RCNNRi Threadfin shad Might Silver chub Emerald shiner Spotted sucker Channel catfish White bass Yellow bass Green sunfish Bl ueg l 1 I
,h. h hP Longear sunfish Redear sunfish White crappie Freshwater drum
.50 .75 f00 Figure 3 Numbers impinged for selected species during the 12-hour periods 060'0.-1800 hours and 1800&600 hours. This graph depicts the results of 42 pooled day/night samples collected between March 19T4-November 1976.
26 The seven species which showed the greatest tendency for impingement during the night were skipjack herring, silver chub, emerald shiner, spotted sucker, white bass, redear sunfish, and white crappie (Figure 3). For~each of these over two-thirds of the individuals were impinged during hours of darkness.
Co arison of Im in ament Aeon Intake Screens Comparison of the distribution of impinged fish (all species combined) among screens for the three operational periods showed differences to be pro-nounced during one-unit (screens 1-6) operation (Figure 4). The Kruskal-Wallis procedure selected two subsets of difference among screens. Multiple comparisons selected two subsets of screens with similar impingement: screens 01, 02, 03, 04, 05, and screens 03, 04'5, and'6; During the second and third operational periods,'he frequency histogram (Pigure 4) suggested that higher impingement tended to occur on the end screens; however, no statistically significant differences among screens were detected.
Size Distribution of I in ed Pish Pish smaller than 51 mm appeared to be relatively insusceptible to impingement for all 12 species examined (Figures 5 end 6). Over 70 percent of the impinged fish were between 51-100 mm total length for eight species:
skipjack herring, gizzard shad, threadfin shad, channel catfish, white bass, yellow bass, green sunfish, and white crappie. Except for white crappie, those fish less than 101 mm total length are considered to be young-of-year.
Individuals of 76-100 mm length represented over 30 percent of the impinged white crappie. White crappie of this s$ zc are probably io the second growth season. For the remaining four species (bluegill, redear sunfish, sauger and freshwater drum), fish more than 100 mm in total length accounted for a
27 Unit 1 oynratton HI 4/40 are 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 Unit 1-2 operation tt 22raa2 20 g
,10 01 02 03 04 05 06 07 Od 09 10 11 12 13 14 15 16 17 18 Unit 1-2 operation tts 27,241
&10 20 10 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 Screeae Figure 4 Distribotion of impinged fish (a11 species combined) among screens at Browne Ferry Nuclear Plant for three levels of plant generation. These comparisons include only those samples when all screens ware in use. N is the total number of fish in all 24-hour samples. S is the number of 24"hour samples ~
Skip)eck herring 0- 25 Gizzard shad 26- 50 51- 75 76-100 101-125 126-150 151-175 l76-Threadfln shad 0- 25 Channel catfish 26- 50 51- 75 76-100 101-125 126-150 15:I.-175 176-White bass Yellow bass 0- 25 26- 50 53- 75 76-100
)0)-125 126-150 151-175 176-100 75 50 25 Length Class 25 50 75 100 (mm)
Percent Percent Fg~ute 5. l.ength frequency distrlbut ton for s< lected fish species Impinged nt, Browns Ferry Nuclear Plant during thc period Herch l974-August l917.
29 Green sunfish 0- 25 8luegl l l 26- 50 51- 75 76-100 101 .'.25 126-150 151-175 176-Redear White crappie 0- 25 26- 50 51- 75 76-100 101-125 126-150 I
7aaIL 151-175 ~
176- IIII 0-
~
Sauger 25 Freshwater drum 26- 50
~
Ib a
~
76 ioo 101-125
, 126-150 1
151-175 176-75 50 25 Length Class 25 50 75 100 (mm)
Percent Percent Figure 6. Length frequency distribution for selected fish species impinged at 8rowns Ferry Nuclear Plant during the period Harch l974-August 1977.
30 considerable proportion of the numbers impinged. Except for sauger, these larger sizes probably include fish older than young-of-year specimens.
Com arison of Im in ement Estimates with Standin Stock E>>timates During the three operational periods, 30 species werc impinged at an. average rate f one or more. fish per day for at least one of the periods.
Impingement of 1? of these species exceeded l percent of the estimated standing stock (numbers) for one or more operational periods (Tables 6-8).
These included skip)ack herring, gizzard shad, threadfin shad, mooneye, carp, silver chub, blue catfish, black bullhead, brown bullhead, channel catfish, white bass, yellow bass, green sunfish, white crappie, black crappie, sauger, and freshwater drum. Six of these species (mooneye, carp, blue catfish, black and brown bullhead, and black crappie) were either absent or rarely collected in the cove samples. Except for blue catfish, the estimated average impingement of each of these species did not exceed an average of three individuals per day. The remaining species which were impinged at 1 percent or more of the estimated standing stock are discussed below.
Ski ack herrin Estimated impingement of skip)ack herring decreased during the three operational periods while mean numerical standing stock values increased over the years corresponding to the operational periods (Tables 6-8). Thus, despite the lower intake flow and lower reservoir density of skip)ack herring during the first period, the proportion of standing stock removed by impingement was greatest in the first operational period and least during the third operational period (Tables 6-8).
31 Table 6. Estimated standing stock numbers (based on cove rotenone samples) for selected species of fish in Wheeler Reservoir (1974) compared with estimated total imp5ngement of these sp'ecies during the period March 27, 1974-March 26, 1975.
I Estimated Mean Standing Percent of standing stock Total No. ock No h numbers im in~ed Taxa Xmpinged YOY Total YOY Tota1 Skipgack herring 220,964 17.70 27.70 45.97 29. 38 Gizzard shad 190,914 873.05 1,768.30 .81 .40 Threadfin shad 4,553,174 2,447.84 2 '47.84 6. 85 6.85 5 5 Mooneye 437 NC NC Silver chub 8,646 54.26 54.26 0.59 0'59 Golden shiner 660 39. 06 39.06 0.06 0.06 Emerald shiner 3,088 28.85 28.85 0. 39 0.39 Spotted sucker 1,049 11.05 71.81 0.35 0.05 5 5 Blue catfish 3,993 NC NC Black bullhead 892 NC NC Channel catfish 21,716 l. 34 9.79 59.68 8.17 Flathead catfish 508 6.53 13.98 0.29 0.13 White I
bass 14,126 3.61 4.46 14.41 j 1.66 Yellow bass 14.453 36. 66 36.66 1. 45 1. 45 Green sunfish 101154 19. 75 26.67 1.89 1.40 Bluegill 17,556 722. 08 1 I 120. 45 0. 09 0. 06 Longear sunfish 366 282.09 556.01 <0. Ol <0.01 Redear sunfish 7>910 138.01 209.35 0.21 0,14 White crappie 7,826 1.04 2.08 27.71 13. 86 Logperch 2,256 206.63 206.63 O. 04 0.04 Sau ger 3,690 5.90 7.04 2.30 1.93 Freshwater drum 179,501 51.31 102.86 12.88 6.43
- 1. Refers to young-of-year fish.
- 2. Refers to all ages collected in suamer cove samples.
- 3. Based on a reservoir surface area of 27,150 ha.
- 4. Not collected on cove rotenone samples.
'5. Calculation not possible.,
I
32 Tabl<<7. E<<tom<<ted <<t<<nding stock numbers (based on cove rotenone samples) for selected species of fish in Wheeler Reservoir (1975) compared with estimated totnl impingemetg of these speciea during the period March 27, 1975-Hnrch 26, 1976.
Estimated Harm standing I'or< ont of stan<ling sin< k Total no. H to 'k n<l/lln nu~ehe ~ legs tngsil, impinged YOY Total YOY Totn 1 Spotted gar 481 7.46 12.54 0 .24 0 .14 Skipgack herring 98,751 9.80 40. 18 37.11 9.05 Gizzard shad 343,312 8. 96 640.19 141-11 l. 97 Threndfin shad 1,909,'<92 1 ~ 565.04 1,565.04 4.49 4. 49 5
I<at p 1,134 NC 0-51 8. 19 Silver chub 6,509 8. 86 8. 86 2.71 2.71 Golden shiner 388 13.47 13.47 0. 11 O.ll Emerald shiner 2>200 6.71 6.71 1.21 1.21 Spotted sucker 3,178 422.81 475. 78 0.03 0.02 5 5 Blue catfish 2,476 NC NC 5
Blnck bullhead i>187 NC 0.28 15.61 Channel catfish 111435 5.46 22.89 7.71 l.84 Flathead catfish 1,050 9. 24 18,98 0.42 0.20 White hnss 13,408 4.76 5.22 10.37 9.46 Yellow buss 29<936 76.28 77.30 l. 45 1.43 Green sunfish 3,115 88.97 110.04 0.13 0.10 Bluegill 9,423 1,702.98 3,204.60 0.02 0.01 Lor<gear sunfish 452 508.81 1,203.31 <b.ol <0.01 Redear sunfish 2<561 396.99 483.97 0.02 0.02 Spotted bass 791 24.27 27.95 0.12 OvlO Largemouth bass 564 60.52 123.98 0.26 0.13 White crappie 4,996 2. 05 7.00 8.98 2. 63 Logperch 15690 468.06 468. 06 0. 01 0.01 Sauger 1,846 14.37 21. 08 0.47 0.32 Fresh<<ster drum 233,902 151.46 300.17 5.69 2.87
- 1. Refers to young-of-year fish.
- 2. Refers to all ages collected in su<m<<er cove samples.
3: Bused on a reservoir surface area of 27,150 ha.
- 4. Not collected on cove rotenone samples.
- 5. Calculation not possible.
33 Table 8. I!><rim<It>~>tu>><ll>>II >>r>>< k numb>>r>> (I>>>>><><I <>>> <<<>v>> r>><<>>>>>>>> ><>>mI>l>>>>)
Io< ><<<l<'>'t> >I>>'> I< >< of I I><h l>< Wh>><>l< r R<>>>>>rv>> lr I I'>II>) o>>>IIP>j<'qd MIIh Il>u I'III.
u;m>I<<<l I>>I>>l Iml>l>>II< m<>>l <h>rl>>II Ihr I><'rl<><l I 8< I>I > ml>< r 1<II<>- II h>>II>>>028.07 0.66 0. 66 Mooneye 656 5 5 NC NC Silver chub 7,537 96. 43 96.43 0.29 0.29 Golden shiner 5,522 39. 80 39.80 0.51 0.51 I
Emerald shiner 8,003 63. 82 63.82 0.46 0.46 Bullhead minnow 1,230 436.22 436.22 0.01 0.01 Smallmouth buffalo 845 NC 38.66 5 0.08 Spotted sucker 7,395 12. 16 152.46 2.23 5
Blue catfish 2,562 NC 0. 26 36.29 Black bullhead 595 NC 5 5 NC Brown bullhead 1,778 NC NC Channel catfish 24,719 2. 89 67.40 31;50 1.35 Flathead catfish 2,217 13.37 19.20 0. 61 0.43 White bass 50,681 30. 16 33.56 6.19 '.56 Yellow bass 67>005 19.08 21. 06 12.93 11.72 Green sunfish 39,210 14.79 41.33 9.76 3.49 Bluegill 84,977 6,60?.19 8 '94.00 0.05 '.04 Longear sunfish 9,287 1,995.37 3,238.69 0.02 0. 01 Redear sunfish 27,625 227.18 443.92 0.45 0. 21 Largemouth bass 1,771 50.56 277.36 0.13 0.02 White crappie 6,780 0.40 2. 68 62.42 9.32 4 5 5 Black crappie 581 NC NC Logperch 1, 730 215. 58 215.58 0. 03 0,03 Sauger 2,535 ?.20 72.12 1.30 0.42 Freshwater drum 215,783 52.41 239.52 15.16 3.32 1, Refers to young-of-your fish.
- 2. Refers to all ages collected in summer c<>v> samples.
- 3. Based on a reservoir surface area of 27,]50 ha.
- 4. Not collected on cove rotenone samples.
- 5. Calculation not possible.
34 Proportion of standing stock removed ranged from 5.39 percent of all ages in the third period to 29.38 percent in the first period and from 13.33 percent of youngmf-year alone in the third period to 45.97 percent Ln the first period (Tables 6 and 8).
Gizzard shad Impingement of gizzard shad showed a distinct increase during the operational periods, exhibiting an order of magnitude increase in the third operational period over the first operational period. A similar increase in numerical standing stock was observed (Tables 6-8) for the three corresponding yearw of cove rotenone sampling. This increase in standing stock was also SE reflected in the 1977 cove samples after high impingement of the previous year's standing stock.'elatively few youngmf-year gizzard shad were collected in 1975 cove samples (Table 7) and higher than expected impingement of young-of-year occurred during this second period. Except for this case, the proportion of standing stock removed by impingement was between 0.41 percent and 1.97 percent.
2'"
Despite an order of magnitude increase in standing stock estimates of threadfin shad from 1974 to 1976, the impingement of threadfin shad was similar for the first and third periods, (4.55 and 4.64 million fish, respectivelyl Tables 6 and 8). During the second period, the impi'ngement of this species was reduced to approximately 1.9 million fish (Table 7). Maximum proportion of standing stock removed by impingement was 6.85 percent (during the first operational period). In 1977 the standing stock was reduced to an extremely iow level (Table 9).
35 Table 9. Estimated standing stock numbers (based on cove rotenone samples) of selected species of fish in Wheeler Reservnir (1977}.
3 Me n standin stock No/ha Spec ies YOY Total Skip)ack herring 30.2 33.2 Gizzard shad l0 ~ 434.4 15,615.3 Thre r>>lfln>>had /~ 1 fi. 0 4 4 Hooneye Silver chub 72.7 72. 7 Golden shiner 12.6 12.6 Emerald shiner .2 .2 Bullhead minnow 185.6 185. 6
"
'Smallmouth buf falo 3.8 21.4 Spotted sucker 15.8 168.3 4 4 Blue catfish 4 4 Black bullhead 4 4 Brovn bullhead Channel catfish 15. 2 21. 2 Flathead catfish 10.9 16.5 White bass 63.3 66.4 Yellow bass 235.8 237.9 Green sunfish 72. 6 126.3 Bluegill 2,351.8 3,880.6 Longear sunfish 706.3 1,847.6 Redear sunfish 600.1 765.5 Largemouth bass 118.7 193.6 White crappie 2.1 88.8 4 4 Black crappie Logperch 573. 5 573.5
, Sauger 55. 4 60,0 Freshwater drum 199,7 348.1
- 1. Refers to young-of-year fish.
- 2. Refers tn all ages collected in summer cove sample <<. ~
- 3. Based on reservoir surfact area nf 27,150 ha.
- 4. Not collected in cove rotenone samples.
Carp were impinged in relatively high, numbers only during the second period. The estimated 1,134 fish represented 8.19 percent of the estimated standing stock of this species in Wheeler Reservoir.
,Silver chub Silver chub impingement remained essentially constant throughout
~he three periods at levels not exceeding an estimated 9,000 individuals per year. The proportion of standing stock removed by impingement was least
'ln the third period (0.29 percent).
Channel catfish Channel catfish were impinged in similar numbers during the first and third operational periods. Numbers were lowest during the second period.
Standing stock increased during the corresponding three years of rotenone sampling (Tables 6-8).
The data suggest that a relatively high proportion of youngmf-year standing stock (59.68 percent, 7.71 percent, and 31.50 percent in 1974, 1975, and 1976, respectively) were impinged. Computations using standing stock numbers for all size classes combined resulted in a much lower proportion removed during these years (8.17 percent, l.84 percent, and 1.35 percent, iespect1vely; Tables 6-8) .
White bass Tmpingement of white bass was over three times higher for the three-unit operational period than for the first and second operational periods.
Standing stock numbers increased an order of magnitude from 1974 to 1976 I
37 (Tables 6-8). As a result, the proportion of standing stock numbers of white bass in Wheeler Reservoir that were impinged decreased from the first to the third operational period. Overall, the proportion of standing stock numbers removed due to impingement ranged from 14;41 percent for young-of-year in 1974 to 6.19 percent in l976 and from 11.66 percent for all ages combined in 1974 to 5.56 percent in 1976. Despite the increaseg number impinged during the third period, standing stock of young-of-year and all ages combined of white base increased from 1976 to 1977 (Table 9).
Yellow bass Impingement of yellow bass showed a marked increase over the three operational periods while mean numerical standing stock in Wheeler Reservoir tended to decrease during this period (Tables 6-8). Consequently, highest relative impingement occurred during the three-unit operational period. The proportion of standing stock reanved by impingement increased from about 1.5 percent during the first two periods to over ll percent during the third period (three-unit operation). Despite the high impingement during the three-unit operation, standing stock of young-of-year increased an order of magnitude
, in 1977 (Table 9).
Green sunfish Impingement of this species increased from 10,154 during the first period to 39,210 during the third operational period (Tables 6 and 8). Conversely, corresponding standing stock estimates decreased from tne first to the third period, resulting in the highest proportion of standing stock being impinged during the third period (9.76 percent of )uveniles and 3.49 percent of 1
all ages combined). The results of cove sampling in 1977 (Table 9), however, showed the greatest standing stock in this year.
White cra ie Impingement of vhite crappie shoved a slight decrease during the three operational periods (numbers were lovest for the third operational period). Standing stock numbers of white crappie were relatively stable over the first three study years (Tables 6-8) and increased greatly in 1977.
Low abundance of young-of-year vhite crappie in the 1976 samples resulted in the high relative impingement (62.42 percent of standing stock numbers) for this age during the three-unit operational period (Tables 6-8). Also, impingement vas high compared to estimated standing stock during the first phriod (27.71 percent of young-of-year and 13.86 percent of the total summer standing stock of all sixes).
~Sau eL'mpingement of sauger ranged from approximately l,&00 fish in the second period to about 3,700 in the first period. Standing stock estimates increased considerably from the first to the third period (Tables 6-8). The proportion of total standing stock removed by impingement exceeded 1 percent only in the first period.
Freshwater drum Impingement of freshvater drum vas highest during the second operational period when intake volume and number of screens in operation vaa least (Table 7).
Standing stock estimates for both young-of-year and all ages combined reflected this unexpected outcome and vere greatest during this period (Table 7). Impinge-mept of freshwater drum appears to be a function of reservoir abundance. The highest relative impingement (Tables 6 and 8) of young-of-year drum vas in the third period (15.16 percent of standing stock numbers and in the first period
39 for all ages combined (6.43 percent). Standing, stock was greatest in 1977 (Table 9) following the three years of impingement monitoring.
DISCUSSION V
The large number of species collected on the intake screens at Browne Ferry Nuclear Plant indicates that the intake is not particularly selective. Impingement probably represents a good qualitative picture of the fish community in wheeler Reservoir. This idea is supported in that species which were unique to either impingement or cove rotenone samples were uncommon
(< 0.05 percent of the total number collected), Compared with the proportional composition of the rotenone samples, a relatively higher percentage of threadf in shad and skipjack herring were impinged on the intake screens. Sunfish species were impinged in proportions considerably less than those estimated by cove rotenone samples. Thus, the pelagic and highly mobile shad and herring seemed to be more susceptible to impingement than sedentary shoreline species such as the sunfish. It is recognised, however, that cove sampling probably over-estimates reservoir densities of sunfish and underestimates the more pelagic species.
Impingement (all species combined) was lowest for the second operational period when intake flow was lowest and highest for the three>>unit operational period when volume intake of cooling water was greatest. Thus, overall there was a positive relationship'etween the level of plant operation and impingement.
However, differences in impingement among operational periods for several of the dominant species (e.g.. spotted sucker, silver chub, white crappie, and sauger) did not appear to be related to pjant operation an<I may have rcfl<<ct<<d year class variation of these species in the reservoir.
40 Several deviations from the "typical" seasonal pattern for monthly impingement of clupeids .occurred after the start of three-unit operation at Browns Ferry Nuclear Plant. The high fall impingement (approximately 4.5 million fish from September through November 1976) was probably due to a large standing stock of young-of-year clupeids in Wheeler Reservoir. High impingement in November may also reflect unusually high natural mortality of threadfin shad due to cold shock from exceptionally low water temperatures during 1976-1977
).
(Fig ure 2). D ecreased impingement during December-February, with even colder water temperatures, suggests that this earlier natural mortality may have severely reduced the numbers of threadfin shad available for impingement.
The failure of clupeid impingement as well as standing stock to increase to usual levels the following susaner suggests that exceptionally high natural mortality of 'fish the previous winter resulted in much reduced levels of recruitment during the spring. Thus, the low impingement of clupeids in late summer 1977 probably reflects low abundance of threadfin shad in Wheeler Reservoir.
Higher impingement during the night may be the result of (1) diel changes in the distributions of these species in the reservoir (e.g., shoreward movement during the night) causing the fish to become more abundant in the intake area during nocturnal periods and/or (2) decreased ability to avoid the intake during the hours of darkness. it e erogene ty among replicates Excessive heteroge used to statistically examine the difference between een day ay an i i i a d n g h t impingement accentuates the highly variable and sporadic nature of impingement. This probably reflects the contagious distributional nature of these species in the reservoir.
41 Impingement was fairly uniformly distributed among screens except during the one-unit operational period. High impingement on the end screen(s) is probably the result of higher density along the intake channel shoreline. During the one-unit period, the return channel from the cooling towers had not been excavated. A corner was created by the intake channel shoreline and left side (Unit 1 screens) of the intake pumping station. These results suggest that for three-unit operation of Browne Ferry Nuclear Plant, the distribution of fish in the intake channel probably had no significant effect on impingement differences among screens.
For most species examined, the intake screens at Browne Ferry primarily impinged young~f-year fish larger than 51 mm in total length. Th' absence of smaller individuals probably is due to the size opening of the intake I
screen. Smaller fish could be abundant in the intake but would pass through the screens and be entrained with the cooling water. The predominance of juvenile fish in impingement samples is probably a result of several factors: (1) the greater relative abundance of these age classes in the reservoir (e.g., the high impingement of clupeids during late suuaaer months is related to the high abundance of juveniles of this group in the reservoir}; (2) juvenile fish of some species may concentrate in shoreline areas and thus be relatively more susceptible to the intake at Browns Ferry Nuclear Plant; and (3) juveniles are il weaker swimmers than adults of the same species and thus are more likely to be impinged given similar exposure levels.
For three dominant species (skipjack herring, channel catfish, and freshwater drum) which exhibited high impingement levels compared to estimated standing stock, relative as well as total impingement for the third period was less than or similar to that for the first period. This suggests that impingement
42 at Srowns Ferry Nuclear Plant was not directly related to standing stock or intake water flow for these species. White base also showed lowest relative impingement during the third period despite increased total impingement.
Standing stocks of this species increased over the four-year period (1974-1977}.
Mhite crappie and yellow base showed higher relative impingement during the third than during the first operational period. The potential for adverse impact from impingement for white crappie appears to be minimized by the fact the estimated 12~nth impingement was actually slightly less for e three-unit than the one-unit operational period. The estimated impinge-ment for the three~nit operational period probably included fish from the abundant 1975 year class. Recruitment of white crappie in Wheeler Reservoir during 1976 was apparently very poor and resulted in high relative impingement for the corresponding operational period.
Although impingement of yellow bass was highest during the three-unit operational period, the large increase in standing stock the following year suggests that impingement did not have an adverse impact on this species.
Mopneye, blue catfish, and black bullhead were infrequently collected in cove rotenone samples; hence, it was difficult to assess the potential for adverse impact due to impingement. Since these species are routinely collected in other types of sampling and since estimated numbers impinged were small, the possibility of a deleterious effect to the reservoir population appears unlikely.
Sunfish impingement increased approximately fourfold from the first tq the third operational period. Except for green sunfish, the standing stock estimates were much greater in 1976 than in 1974. The proportion standing stock r~ved by impingement was low (< 1 percent} for all periods. Expansion of
43 cove densities of suqfish to reservoir density by che mechnd used here prnhnhly produces an overestimate of reservoir standing stock. However, it i8 experced that, except for green sunfish, adgusting the standing stock to only the productive areas of the reservoir vould show impingement co be lese than 1 percent of che standing stock.
CONCLUSIONS
'early all species in Mheeler Reservoir, excluding some darters And shiners, vere collected from the Browne Ferry Nuclear Plant intake screens ac least once since 1974. For the 42 species impinged at rates estimated co be one fish or less per day, the potential for an adverse impact is lov. None of these species is present in such low numbers that the removal of up to 365,fish per year would adversely affect their populati,ons.
Thirteen of the remaining 30 species vere impinged at rates estimated to exceed one fish per day but in numbers vhich represent less than 1 percent of the estimated reservoir standing stock. hll of these species are common to che Tennessee Valley and, except for bluegill and redear sunfish, less than 1O,OOO fish per year of each species vere estimated to be impinged. For these species this level of impingement is not considered sufficient to cause an adverse impact to the respective populations in Mheeler Reservoir. Furthermore, although bluegill and redear sunfish vere impinged in high numbers, compared co the estimated standing stock this loss.(< O.l percent for bluegill.and < O.S percent for redear) appears to be negligible in terms of impact tn their populations.
Five of the remaining 17 species vhich vere impinged at rates exceeding 1 percent of the estimated standing stock for at least. one 12-month period were
44 rarely collected in cove samples. Because these species (mooneye, blue catfish, black and brovn bullhead, nnd black crappies) arc common in Tennessee Valley vaters and vere impinged at rate" estimated to be less than three individuals per day, impingement is not considrred to have the notential for adverse impact.
The remaining lo species vere impinged in numbers exceeding 1 percent of their estimated standing stocks. Among these, ,tanding stock data for skipJack herring and gizzard shad did not reveal any effect of plant operation on their population levels in Wheeler Reservoir. For both species the proportion of standing . tock impinged vas least in thc third period vhen standing stock estimates vere highc. t.. At thc end of three years of'peration nnd monitoring, these populations do not appear to have been adver ely af'fected by the Brovns I'erry Plant. The much reduced standing stock of threadfin shad in 1977 reflects the effect of lov trmperature rnther than any effect of the intake. It, is cxnected that the rrcnvrry of this species vill be independent of plant operation.
It. is very unlikely that the impingement of 1,134 carp per year vould pose an adverse impact to this population. Similarly, silver chub, a species commonly impinged throughout much 1
of the Tennessee Valley, vas collected in sufficiently lov numbers to preclude the poss5bility of an adverse impact to the Wheeler Reservoir population.
Channel catfish densities are probably poorly estimated by cove rotenone sampling. This species appears to be more charncterist5.c of the main-stream portion nf the reservoirs. Standing .". ock numbers increased -through-cut the three years of monitoring and annual impingement did not increase appreciably from the fi.rst to the third operational period (maximum 25,000 .ishI, zherebv demonstrating thr absence of adverse impact.
The increased impingement of ~hite bass from the first to the third period,may be due to both increased plant operation and increased abundance.
The density of this fish is also probably underestimated by cove rotenone since it is a pelagic species more characteristic of the open reservoir, Since the standing stock of white bass increased from 1976 to 1977 despite impingement of 51,000 inuividuals of the 1976 standing stock, impingement of white bass does .not constitute an 'adverse impact.
The Yellow bass population probably experienced no adverse impact from impingement. Although increasing impingement coupled with decreasing standing stock estimates during the monitoring period resulted in a maximum stock removal of 11.22 percent for all ages combined, the very high standing stock of young-of-year in 1977 probably precludes an adverse impact.
Green sunfish showed a trend of increasing impingement and decreasing standing stock which resulted in greatest potential for impact during the third period of three-unit operation. However, neither the total number impinged nor the proportion of standing stock impinged is expected to adversely affect this population. The decreasing trend in green sunfish standing stocks was continuous from 1969 through 1976. Additionally, the increased standing stock in 1977 indicates that the impingement has not adversely affected this population.
White crappie were probably greatly underestimated by cove sampli,ng.
The impingement of up to 8,000 individuals per year is not expected to represent an adverse impact to the Wheeler Reservoir white crappie population. Similarly, the removal of up to 3,700 sauger per year is not expected to adversely affect the reservoir population.
Freshwater drum impingement appears to be more related to standing stock than to the level of plant operation. Since the proportion of drum stocks
46 removed by impingement and the annual impingement has not increased through-out tho years ol plant operation, the posslbtllty of an ndverso fmpact ls unl ike1y.
In suaaaary, the overall impingement of fish at Brogans Ferry Nuclear Plant does not appear to represent an adverse environmental impact to the Wheeler Reserv ~r f.'ah community.
47 IeITERATURP CITED Hollander, H., and D. A. %olfe. 1973. Nonparametric statistical methods. John Nley and .";ons, Inc. 503 pp.
Sokal, R. R., and P. S. hohlf. 1969. 3iometry. M. H. Preeman and Company, San Francisco, California. 776 pp.
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