ML20053C662

Forwards Addl Info in Response to Request for Alternative Siting Analysis Including Possible Presence of 11 Species of Endangered Freshwater Mussels in Vicinity of Facility

ML20053C662
Person / Time
Site:	Clinch River
Issue date:	05/28/1982
From:	Longenecker J ENERGY, DEPT. OF
To:	Check P Office of Nuclear Reactor Regulation
References
HQ:E:82:019, HQ:E:82:19, NUDOCS 8206020442
Download: ML20053C662 (39)

Text

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• Department of Energy Washington, D.C. 20545 Docket No. 50-537 HQ:E:82:019 MAY 2 81982 Mr. Paul S. Check, Director '

CRBR Program Office .

Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission '

Washington, D.C. 20555 ,

Dear Mr. Check:

ADDITIONAL RESPONSE TO REQUEST FOR ALTERNATIVE SITES INFORMATION Enclosed is an update to the CRBRP alternative siting analysis, within the TVA power service area, that encompasses and expands upon the additional - 4 information provided in Attacinent 1 of my letter to you dated February 12, 1982. Also included as part of this alternative siting analysis update is additional information further addressing NRC staff concerns on the possible presence of 11 species of endangered freshwater mussels in the '

vicinity of the Clinch River site and the possible impact on striped bass of CRBRP thermal discharges during a potential period of extended zero releases from Melton Hill Dam during the hot summer and fall months.

This expanded update analysis does not change the previous conclusions on the environmental acceptability of the CRBRP site or the Project's selection of the Clinch River site as the preferred site for the LMFBR Demonstration Plant. 3 The enclosed update was informally provided to Mr. P. Leech on May 14, 1982, and will be included as part of Amendment XIV (May 1982) to the Environmental Report.

incerely, k.

J n R. Longene r, Manager ens 9 & En & onmental 8206020442 020528 oor natjon PDR ADOCK 05000537 A PDR Office, of Nuclear Energy Enclosure cc: Service List Standard Distribution h ' I Licensing Distribution

4 UPDATE TO THE CRBRP ALTERNATIVE SITING ANALYSIS WITH IN THE TVA POWER SERVICE AREA .,

1.0 BACKGROUND

AND INTRODUCTION The al ternative sitlog analy sis f or the CRBRP is presented in Section 9.2 of the CRBRP Environmental Report. The choice of the TVA power service area as the region of interest for th is analysis was inherent in the selection by AEC of the TVA/ Commonwealth Edison proposal for a cooperative AEC/ utility arrangement to design, construct, and operate tha nation's first l arge-scal e demonstr ati on LMFBR.I The alternative siting analysis in Environmental Report Section 9.2 was conducted in accordance with 10 CFR Part 51 and Regulatory Guide 4.2. The conclusion reached in Environmental Report Section, 9.2 after careful consideration of both hook-on arrangements at existing TVA plants and an entirely new plant at undeveloped candidate sites, was th at an al l new plant located at the Clinch River site was the pref erred choice f or the LMFBR Demonstrati on Pl ant. In response to admittance by the NRC Commissioners of an NRDC contention concerning the CRBRP Project's alternative siting analysis and a subsequent NRC request for additional Information, the Project provided in Environmental Report Appendixes D and E an analysis of alternative sites outside the TVA power service area and the concepts of underground siting and co-location with an LMFBR f uel reprocessing or fuel f abricati on plant.

The concl usion reached f rom th is supplemental alternative siting analysls was again that the Clinch River site was the pref erred site for the LMFBR Demonstration Plant.

Based on the Project's alternative siting analyses and thei r own independent ana l y ses , the NRC staf f in the Final Environmental I See CRBRP Environmental Report Sec'tlon 9.2 and Appendix D, Section 1.0 for additional information concerning the history and selection of an AEC/ utility arrangement for the design, construction, and operation of the LMFBR Demonstr ation Pl ant.

a Statement (FES) for CRBRP (NUREG-0139), dated February 1977, concluded

" . . . . th a t the applicant's preferred proposal, utilizing the Clinch River site, is reasonable and that no substanti al ly better al ter ;iative is available." The choice of the Clinch River site for the LMFBR Demonstration Plant has al so been conf irmed by DOE's LMFBR Progr am Supplemental Environmental Impact Statement.2 In addition, it is important to point out that the Clinch River site environmental and safety analyses, completed subsequent to the Project's selection of the Clinch River site, have demonstrated that the Clinch River site is a total ly acceptable site f or construction of the CRBRP.3 Following the restart of NRC's CRBRP licensing review in the fall of 1981, NRC requested additional information to update the Project's alternative siting analyses presented in the Environmental Report.

The requested update to Environmental Report Appendixes D and E, consisting of a reexamination of the previous analysis of alternative DOE sites, TVA owned sites outside the TVA power service area, and the concepts of underground siting and co-location w ith an LMFBR fuel reprocessing or fuel fabrication plant, was provided in Attachment 2 of a letter J. R. Longenecker (DOE) to P. S. Check (NRC) dated February 12, 1982. Attachment I to th is same letter provided additional Information to update the Environmental Report alternative siting analysis presented in Environmental Report Section 9.2 and Appendix A. This present update encompasses, but expands upon, the edditional information provided in Attachment I of the Project's February 12, 1982 letter in order to address all of NRC's questions that have been raised concerning the CRBRP alternative siting assessment considering the TV A power service area as the region of interest.

NRC's request for additional information specifically requested th at the previous assessment in Environmental Report Section 9.2 be 2 See the LMFBR Program Supplemental Environmental impact Statement, 00E/EIS-0085-0, Appendix G.

3 See the CRBRP Environmental Report and Preliminary Safety Analysis Report (PSAR) and NRC's Final Environmental Statement (February 1977) and Site Sultability Report (March 4, 1977) for CRBRP

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a revlewed in the context of NRC's Proposed Rule on Alternative Sites

( 45 FR 2 4168-2417 8, April 9, 1980). To best accommodate this request, this update has been organized along the lines of the al ternative site revlew p,rocess described in the Proposed Rule. Thus, Section 2.0 discusses the acceptability of the TVA power service area as the region of interest, Section 3.0 conf irms that the Project has selected for consideration a state of candidate sites that provides reasonable representation of the diversity of land and water resources within the region of Interest and includes sites that are among the best that could reasonably be found, and Section 4.0 reexamines the comparison of the Clinch River site with alternative sites considering both environmental and project economic, technology, and institutional factors. The conclusion, in light of the Proposed Rule and current information, that the Clinch River site is the preferred site for the LMFBR Demonstr ati on Pl ant is summarized in Section 5.0.

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2.0 REGION OF INTENEST The preamble to NRC's Proposed Rule on Alternative Sites states th at the region of interest should be determined on the basis of environ-mental diversity such that "a substantial range of environmental alternatives from which to chooss in making the final siting decision" is provided. "For the purpose of determining the region of interest, environmental diversity," accordi,ng to the Proposed Rule, " refers to the types of water bodies available within the region (upper and lower reaches of large rivers, small rivers, lakes, bays, and oceans) and the associated physlographic units."

The region of interest for the LMFER Demonstration Plant siting assessment presented in CRBRP Environmental Report Section 9.2 was considered to be the TVA power service area. As can be seen in Figure 1, the region of interest incl udes several rivers ranging in size from small, e.g., the Duck and Elk, up to rather large rivers, e.g., the Tennessee, Mississippi, and Ohio. Additionally, the water bodies vary from free flowing to impounded lakes, and for many rivers include an area f rom thei r headwaters to thei r mouths. Physiographic units associated with these rivers include coastal plains, interior low plateaus, the Appalachlan Plateau, valley and ridge, and Blue Ridge.

Based upon these features, the area TVA serves well qual i f ies it as an acceptable region of Interest.

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4 3.0 SELECTION OF CANDIDATE SITES in terms of the NRC Proposed Rule On Alternative Sites, the original siting assessment in CRBRP, Environmental Report Section 9.2 undertook a product-oriented approach which focused upon the individual qualities of each proposed site. Under this product-oriented approach the Proposed Rule requires (a) that candidate sites be selected "from the region of interest to prov ide reasonabl e representation of the diversity of land andiwater resources within the region of interest,"

and (b) that each site meet specific threshold criteria. A review of the selection of candidate sites in the original assessment versus the new requirements of the Proposed Rule is provided in this section along with a discussion of other potential siting options suggested in NRC's request for additional information dated November 30, 1981.

Within the region of interest, (i.e., the TVA power service area) the original siting assessment considered all TV A steam plants for a possible hook-on arrangement which were expected to be operational on a time schedule consistent with the planned operation of the LMFBR Demonstration Plant (see Environmental Report Table 9.2-1) and 109 "new" sites for an entirely new plant. These hook-on and new sites were on or near certain rivers in the Tennessee and Cumberl and River basins.4 These rivers are identified in Table 1 and are classified in terms of environmental diversity. As this table shows, these rivers and their associated physiographic units, and therefore, sites along them, are consistent with the concept of environmental diversity as discussed in the Proposed Rule.

The slate of 13 candidate sites identified in Environmental Report Section 9.2 and Appendix A was derived from the above set of hook-on Although the Thomas H. Allen Steam Pl ant and the Shawnee Steam Plant are located on the Mississippi and Ohio Rivers, respectively, these

)lants along with the Johnsonvil le Steam Plant were dismissed as nook-on candidates, because of the seismic design uncertainty in the western end of the TVA system at the time of the original siting assessment (see Environmental Report Section 9.2.2, page 9.2-4).

Therefore, these two rivers are omitted from this discussion.

TABLEI  :

CLASSIFICATION OF RIVERS WHERE SITES WERE CONSIDERED FOR THE LMFER DEMONSTRATION IN TERMS OF ENVIRONMENTAL DIVERSITY

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Associated '

Physiogrcphic River River Tvoe Units Tennessee Lcrge, impounded Originates in volley cnd ridge and t

flows through Cumberland Plateau and interior low plateau to coastal -

plain Duck Small, impounded Interior low plateau Sequatchie Small, headwater Appalachian Platecu Clinch Medium to small, Volley cnd ridge impounded, headwaters

'Emory Small, impounded, Valley and ridge  :

headwaters Little Tennessee Small, impounded, Originates in Blue Ridge cnd f!ows headwaters to volley and ridge ,

Tell ico Smpil, headwater -

Originates in Blue Ridge and flows ,

to valley cnd ridge Holston Medium to small, Volley and ridge impounded, hecdwaters

French Broad Medium, impounded, Originates in Blue Ridge and flows headwaters to valley and ridge Nolichucky Small, impounded, Originates in Blue Ridge end flows headwaters to valley end ridge Cumberland River Basin Cumbericnd Large to medium, '

Originctes in interior low plateau impounded -

and flows to coastal plain Red Small, headwater interior low plateau Coney Fork Small, impounded, inte[ior low plateau headwater .

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A and new sites on the basis of engineering and environmental assess-ments. As can be seen from Figure 1 and Table 2, the 13 candidate si tes adequatel y ref l ect the env ironmental diversity in the region of interest (i.e., the TV A power, serv ice area).

The second requirement of candidate sites stated in the Proposed Rule is that each candidate site should meet the threshol d criteria stated in Section VI.2.b. When reviewed in terms of Information present at the time of the original assessment, all of the 13 candidate sites meet the threshold criteria with the exception of the Rieves Bend site which would not have met criteria one, four, and eight related to water resources. However, the Rieves Bend site could h ave been excluded as a candidate site without diminishing in any way the repre-sentative environmental diversity exemplified by the r em a i n i n g 12 candidate sites.

5 The slate of candidate sites nas also reviewed in terms of the threshold criteria af ter having considered appropriate current Informat;an. Current information did not adversely affect any site's ability to meet the threshold criteria, and prev ious assessments have essentially been substantiated, in addition, the following information concerning the sites was not avail able at the time of th e earlier assessment.

1. The probable maximum flood elevation has been redefined for several of the sites, but the associated design changes and additional costs th at wou l d resul t woul d be within five percent of overall project cost as discussed j in threshold criterion number eight.

5 The John Sevier and Widows Creek sites are not included as candidate sites since the Project is no longer considering a hook-on arrangement at these sites (see letter R. L. Copeland to P. S. Check, " Responses to NRC Questions," dated November 13, 1981, Question / Response 320.1R).

. TABLE 2 CANDIDATE SITES Physiographic Site River River Tvoe Character Spring Creek Tennessee Large, impounded Interior low plateau Blythe Ferry Tennessee Large, impounded Valley and ridge Coney Creek Tennessee Large, impounded Valley and ridge Clinch River Clinch Small, riverine, Valley and ridge impounded Taylor Bend .

French Broad Small, impounde'd, Valley and ridge headwater .

Buck Hollow Holston Medium, headwater . Valley and ridge.

Phipps Bend Holston Medium, headwater Valley and ridge Lee Valley Holston Small, headwater Valley and ridge Murphy Hill Tennessee Large, impounded Appolochion Plateou Johntown Cumberland ' Medium, riverine, Interior low plateau (Hartsville) '

impounded Rieves Bend Duck Smoli, potentially Interior low plateau impounded John Sevier Holston Medium, impounded, Valley and ridge headwater Widows Creek Tennessee Large, impounded Appalachian Plateau g e 9

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2. A coal gasification plant is under construction on the Murphy Hill site.

3. Light water nuclear plants are under construction at the Hartsv il l e (Johntown) and Phipps Bend sites.

The conclusion, based on th is rev iew of the candidate sites presented in Environmental Report Section 9.2 and Appendix A is that the original site assessment meets the Proposed Rule Section VI.2 requirements for selection of candidate sites, i.e., th at a sufficient number of candidate sites th at meet the threshold criteria were identi f led to reasonably represent the env iron-mental diversity of the TVA power service area.

In addition to the request to review the previous site selection process in light of the Proposed Rule's requi rements and currently available information, NRC also asked several specific questions requesting (1) the rational e and supporting information for exclusion of potential candidate sites along the Mississippi, the Ohio (at or in the vicinity of the Shawnee Steam Plant), the Tombigbee, the Black Warrior, the Coosa, the Green, the Barren, and the Pearl Rivers; (2) reconsideration of the possibl e use of planned or existing power plant sites, including Phlpps Bend, Hartsville, Yellow Creek, Watts Bar, Browns Ferry, Sequoyah, and Bellefonte; (3) whether an all new LMFBR Demonstration Plant could be built at the hook-on sites previously compared to the proposed Clinch River site; and (4) whether another suitable candidate site exists on the Clinch River including the possi-bility of locating an all new LMFBR Demonstr ation Pl ant at the Bull Run or Kingston Steam Plant sites.

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In response to tre first question, the Missi ssi ppi River and the Ohio River near the Shawnee Steam Plant were excluded because of the seismic design uncertainty due to their proximity to the New Madrid sei sm ic zone. The Green, Pearl, Barren, Coosa, Tombigbee, and Black Warrior Rivers were excluded because only their head-waters are located in the region of Interest and these headwater areas did not appear to exh ibit adequate cooling water capabil-Itles, i.e., siting opportunities. Additionally, since other small rivers with simil ar physiograph ic characteristics were considered, there is fully adequate environmental diversity despite the absence of these rivers.

Questions 2, 3, and 4 all suggest the co-locati on of the LMFBR Demonstration Plant with planned or existing TVA power plants.

The Project has not considered the viability from an engineering standpoint of siting an al l new plant at an existing or planned TVA power plant site since the Project has identified a suf-ficient number of new (i.e., undeveloped) cand idate sites th at meet all the se l ect i on requi rements of the Proposed Rule.

Therefore, there"Is no need f or consi derati on of co-locati on alternatives.

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The fourth NRC question above also asks if another suitable candidate site exists on the Clinch River. Whil e we recognize that the Proposed Rule suggests that one of the al ternative sites have the same water source as the proposed site, TVA's siting studies have not identi f ied any other potenti al site on the Clinch River suitable for location of a nuclear power plant.6 in summary then, the Project, in response to NRC's request for additional Information (Question 750.2R), has identified, based

'I on a revlew of the original siting assessment presented in Environmental Report Section 9.2 and Appendix A, ten candidate sites that provide reasonable representation of the diversity of land and water resources within the region of interest, each of which meets the eight th res ho l d criteria of Section VI.2.b of the Proposed Rule. These ten candidate sites are Spring Creek, .

Blythe Ferry, Caney Creek, Clinch River, Taylor Bend, Buck Hollow, Phipps Bend, Lee Valley, Murphy Hil l, and Hartsvil le (Johntown). To th is list the Project, for purposes of the environmental evaluation, in Section 4.0, has added Yellow Creek.

Yellow Creek is a representative site of the western area of the TVA power service area where at the time of the original LMFBR Demon str ati on Pl ant siting assessment, nuclear power facilities had been restricted due to unresolved questions about regional seismic activities and uncertainties in licensing a nuclear power plant there. However, in June 1972 TVA submitted to the AEC for 6 TVA has conducted siting studies to identify altes in the northeastern portion of the TVA system encompassing the Clinch River system. During the course of these studies, 34 potential sites were l Identified and examined of which 13 were located on the Clinch River or Norris Reservoir. Six of these sites were specifically included in the 109 new sites that were reviewed for the LMFBR Demonstration Plant siting assessment. Upon f urth er exam inati on, it was determined that none of the sites in the Clinch River system except the proposed Clinch River site met the enginearing requirements of a large power plant. Among the reasons f or elimination were poor f oundati on conditions, water supply, fl ooding potenti al, and environmental factors, such as proximity to wildlife and r ecr eati ona l areas (see TVA's " Site Evaluation Report, Nuclear Units X21-22, X24-25," dated February 1975).

9 Its review a report, " Relationships of Earthquakes and Geology in West Tennessee and Ad,*acent Areas,"7 and in November 1973 TVA received a favorable letter from the ACRS on the findings presented in this report. As a result, TVA believed it coul,d gain NRC's approval for a site in TV A's western area upstream of Tennessee River mil e (TRM) 170. This has been conf irmed by the NRC's granting a construction permit for the Yellow Creek Nuclear Plant.

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7 Relations!'!ps of Earthquakes and Geology in West Tennessee and Adjacent Areas, Dr. Richard G. Stearns and Dr. Charles W. Wil son, Jr.,

Department of Geology, Vanderbil t University, U.S. TVA, June 1972.

4.0 COMPARISON OF THE CLINCH RIVER SITE WITH ALTERNATIVE SITES The Proposed Rule For Alternative Sites states:

The NRC will determine obvious superiority among the candi-date sites by a sequential two-part analytical test. The first part gives primary consideration to hydrology, water quality, aquatic biological resources, terrestrial resources, water and land use, socioeconomics, and population to deter-mine whether any alternative sites are environmentally preferred to the proposed site. The second part overlays consideration of project eco n om i cs , technology, and insti-tutional factors to determine whether, if such an environ-mentally preferred site exists, such a site is, in fact, an obviously superior site.

In accordance with the first part of the Proposed Rule's sequential two-part analytical test, Section 4.1 compares the eleven candidate sites identified in Section 3.0 (i.e., the proposed Clinch River site and the ten alternative candidate sites) considering environmental factors. Even though Section 4.1 finds that none of the ten alternative candidate sites is environmentally p' referable to the Clinch River site, Section 4.2 discusses and demonstrates th at even had an env ironmental ly preferred site been identified, the second part of the Proposed Rule's two-part test for obvious superiority would show that consi derati on of project economics and institutional factors (i.e., the LMFBR program timing objective) would lead to a f inding that no alternative site is an obviously superior site to the preferred Clinch River site.

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4.1 Environmental Preferabilltv Test The original siting analysis presented in Environmental Report Section 9.2 and Appendix A compared each of th e or i g i n a l 13 candidate sites (See Table 2) in terms of not only environmental factors but also with regard to economic and engineering characteristics (i.e., access facilities, transmission facilities, geology ( f oundati on conditi ons), seismology, bydrology (flooding), and meteorology). In the Project's February 12, 1982, response to NRC's request for additional information concerning the original siting analysis, the Project presented the results of a reexam inati on of the Environmental Report Section 9.2 and Appencix A siting analysis in light of th e Proposed Rule. Based on th is rev iew, the Project concluded that the add lon of current inf ormati on f or the most part Indicates that.the data used in the original as ses sment rema i n ap pl i cab l e today except for the changes prevlously noted in Section 3.0.

Thus, as a result, the rev iew of the or iginal siting assessment with the addition of applicable current information gave rise to no candidate site' which could be considered environmentally preferable to the Clinch Rive. site.

Subsequent to the February 12, 1982, submittal, the Project conducted a separate analysis comparing the environmental siting characteristics outlined in the Proposed Rule's selection requirements with the el even cand i date sites th at were identified in Section 3.0. These eleven sites are the proposed Clinch River site and the ten alternative candidate sites of Spring Creek, Blythe Ferry, Caney Creek, Taylor Bend, Buck Hollow, Phipps Bend, Lee Val ley, Murphy Hil l, Hartsv il l e, and Yellow Creek. This subsequent analysis was done in accordance with the first part of the Proposed Rule's sequential two-part analytical test giving primary consideration to hydrology, water quality, aquatic biological resources, terrestrial resources, water and land use, socioeconomics, and population to determine if any of the ten al ternative candidate sites are environmentally preferred to the proposed Clinch River site. The conclusion of this assessment substantiated all of the previous siting analyses by f inding that none of the ten alter-native candidate' sites examined are judged to be environmentally preferred to the Clinch River site.

During the NRC staff's revlew of the Clinch River site following the renewal of CRBRP licensing in the fall of 1981 a number of new issues have been raised by the staf f that coul d impact the above findings. These issues are separately addressed in the following subsections. These issues concern (1) the U.S. Fish and Wil dl i f e noti f ication to NRC th at 11 species of endangered freshwater mussels may be present in the vicinity of the Clinch Rivbr site ('see NRC Questin 290.11R) and (2) the possible impact on striped bass (Mangne saxattlis) by CRBRP thermal discharges during a postulated period of extended no Clinch River flow at the CRBRP site during the hot summer and fall months.

4.1.1 Endangered Freshwater _ Mussels in its November 30, 1981, request to the Project for additional information for environmental review of the CRBRP application, NRC asked for all available information concerning the possible presence of 11 species of endangered freshwater mussels in the vicinity of the Clinch River site (Question 290.11R). In letters, J.R. Longenecker (DOE) to P.S. Check (NRC) dated December 21, 1981, and January 28, 1982, the Project provided a response to th is question. The response concluded that due to

• the limited amount of suitable substrate and the failure of several surveys to encounter significant mussel populations, the potential for the occurrence of endangered mussels in the vicinity of the Clinch River site i s remote. The Project has, however, committed to conducting a survey of freshwater mussels in the vicinity of the Clinch River site in order to confirm th at no endangered freshwater mussels are located in the Clinch River near the CRBRP site. A description of the proposed survey is encl osed as Appendix 1. The survey will be performed when water clarity and flow' conditions are optimal which means, based on historical conditions, the survey shoul d be perf ormed sometime in June 1982. A full report covering the survey and its eval uation will be prepared and provided to NRC.

Therefore, based on the information provided by the Project in the response to NRC Question 290.11R, th e r e is no reason to bel ieve th at any of the suggested 11 species of endangered f reshwater mussel s are present in the vicinity of the Clinch River site. This should be conf Irmed by the proposed Clinch River survey. Thus, the concern regarding the presence of endangered freshwater mussels should not be a factor in determining whether an alternative site is environmentally preferable to the Clinch River site.

4.1.2 Clingh River No-Flow Conditions The Environmental Report in Section 2.5.1.3 discJsses that historical low flows at the Clinch River site have, resulted from regul ated rather th an f rom natural flows because The Tennessee River and Clinch River are " controlled" rivers. The two longest periods of no flow, 29 consecutive days in February and March 1966 and 11 consecutive days in April and May 1967, resulted from

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special reservoir operations conducted to aid in controlling the growth of Eurasian water milfoil in the Melton Hill Reservoir.

As stated in the Environmental Report, such extended periods of zero flow from Melton Hill Dam are not anticipated in the future and should the need arise for any regulation at Melton Hill Dam which would result in long periods of zero release, the oper-ations would be coordinated to meet flow requi rements at the CRBRP site.

Recognizing the potential no flow characteristics of the Clinch River at the CRBRP site, the Project perf ormed thermal-hydraul ic-modeling studies'of the CRBRP d isch arge in order to assess the environmental Impact of the CRBRP thermal discharges. The physical thermal-hydraul ic and math emati cal modeling investi-gations were performed by the University of Iowa, institute of Hydraul ic Rese arch (lowa Institute). A complete description of these studies and the results are presented in Appendixes A and B to Section 10.3 of the Environmental Report. A total of six cases were modeled: typical winter case, typical summer case, hypothetical wi nter extr eme case, hypothetical summer extreme case, extended no flow winter case, and extended no flow summer case. Based on the results of the Iowa Institute work, the l

Environmental Report in Sections 5.1.2 and 5.1.3 discusses and l concludes, respectively, that the CRBRP discharge will comply with the Draf t NPDES permit thermal requi rements and th at aquati c l

life in the Clinch River wil l not be seriously impacted by the thermal effluent from the CRBRP.

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The latter conclusion was reached after Individually looking at the various types of aquatic life including fish, benthos, periphyton, and planktonic species ,(i.e., phytoplankton, zooplankton, fish eggs, and larvae).

In the Final Environmental Statement (FES) for the CRBRP (February 1977), the NRC staff reviewed the Project's physical thermal-hydraulic and mathematical modelinq and also presented the results of their own independent analysis of the thermal plume using a three dimensional model. The final conclusion reached concerning the thermal plume effects on the river blota was "In summary, the staff judges the impacts from the thermal discharges upon the aquatic blota to be insignificant."

Recently, as part of its continuing CRBRP review, the staff has indicated a concern for the possible impact CRBRP operation (i.e., thermal discharges) may have on striped bass (M2 rana inxatIIIsl. The specific concern is whether any adverse impact could occur due to CRBRP operation in the hot summer and fall months when the adult striped bass are known to seek the cool thermal refuge of the Cilnch River. The following information is presented in response to this concern about a possible conflict between the CRBRP thermal discharge and use of the river near the CRBRP site as a cool-water refuge in summer and fall by striped bass.8,9 0 Letter, C. Coutant to M. Masnik, dated December 16, 1981. .

9 Cheek, T. E. 1982. Distribution and habitat selection of adult striped bass, Morone saxatills (Walbaum), in Watts Bar Reservoir, Tennessee. Thesis, Tennessee Technological University.

As discussed above, the Environmental Report has analyzed the environmental impact of CRBRP thermal discharges for typical hypothetical extr eme and extended no flow summer and winter cases that i ncl ude c6nd iti ons "more seve-e th an those th at wou l d be anticipated during the lifetime of the f acil ity." Since there is no need for a cool-water ref uge during winter, only the summer cases will be reexamined here.

Maximum temperature rises at the river surface and bottom for th e typical summer and hypothetical oxtreme summer cases are shown in Environment Report Table 5.1-2 and Figures 5.1-2 and 5.1-4. As can be seen, the maximum plant-induced temperature di f f erenti al would be confined to a very small area.

4 During extended periods of no river flow at the site, thermal plume development is initiated. With cessation of flow past the plant, the plume begins to spread out across the river surface from the zone of near-field mixing. As th is spr eading proceeds, the amount of amb ient water avail abl e f or entrai nment in the discharge Jet diminishes and ne ar-f ie l d dilution is reduced.

Initially, p l ume temper ature r i ses ; however, as the surface area encompassed by the plume . increases, heat loss to the atmosphere becomes an important transport mechanism. Eventually, with the plume extending across the full width of the channel for approx-Imately two miles up- and do w n str e am , a point is reached at which the surface area occupied is sufficiently large th at the rate of heat loss th rough surface cooling is equal to the rate of heat addition at the discharge. A steady-state condition is thus attained and no f urther increases in ei ther temperature or spatial extent are realized. As the plume occupies the surface layer of roughly one-third of pool depth, ambient water is present b e ne ath it throughout its length, in the summer no-flow t

case, steady-state conditions are achleved in approximately 10 days. Maximum pl ume temper ature ri se in the transitional zone is 1.3 0F. The plant-induced temperature rise decreases to 1 0F after 3/4 mile in either direction and is.further reduced to 0.50F at u p st r e am and dow n str e am distances of 2 miles as shown in Environment Report Figure 5.1-6.

Under the very unlikely summertime worst case conditions extreme ambient temperatures (740 F or more) in the upper one-th ird of the river water column would be increased less than 1.3 F ne ar the discharge and from 0.5 to 1.0 F w ith in two mil es of the dis-charge. The lower two-thirds of the water column would be unaffected. Thus, under worst case conditions, tour mil es of surface water wilI be he.sted 0.5 to 1.3 F ebove ambient. This compares with approximately 19 ' river mil es between Mel ton Hil l Dam and the confluence of the Clinch and Emory Rivers just u p st r e am of the Kingston Steam Plant. Although striped bass may avoid the slightly warmer surface waters in the vicinity of the discharge, there is no basis for suggesting th at the cool-water refuge will be signifIcantly limited. Maximum surf ace temper-ature in the pl ume near the discharge under worst case hypo-thetical conditions would be less than 80 0F; this is several degrees below the estimated l eth al temperature for striped 1 0,1 1,1 W 3 bass.

i 10 Weddle, H. R., C. C. Coutant, and J. L. W il son. 1980. Summer habitat selection of striped bass, M_orone saxatills in Cherokee Reservoir, Tennessee, 1977. Oak Ridge National Environmental Sciences 1360. Oak Ridge, Tennessee 37830.

j ((visionPublicationNo.

Axon, J. R., 1979. An evaluation of striped bass introductions in Harrington Lake. Fisheries Bul letin of the Kentucky Department of and W11diife Resources, Butletin No. 63.

Fgsh Schalch, B. A., and C. C. Coutant, 1980. A biotelemetry study of spring and summer habitat selection cf striped bass in Cherokee Reservoir, Tennessee, 1973. Environmental Sciences Division PgblicationNo. 1441. Oak Ridge, Tennessee 37830.

I Brungs, W. A., and B. R. Jones, 1977. Temperature cr iteria f or l freshwater fish: Protocol and procedures EPA-600/3-77-051. 130 p.

l

9 Since the warmer water w!Il not penetrate the l ower 'wo-th i rds of the water col umn, thermal blockage would not prevent striped bass from util iz ing the f ive mil es of river between the CRBRP site and Melton Hill Dam. Striped bass migrate past the Kingston Steam Plant which discharges up to 61 m 3 /s of heated vater into the Clinch River at CRM 3.0. Summer temperatures in the Clinch River near the Kingston Pl ant reached 82.80 F at the surface and 79.80F at the bottom during a 1979 TV A study.14 That striped cass pass through th is stretch of river, which is warmer than hypothetical worst case conditions et the CRBRP site, supports the concluster.

that the CRBRP discharge w il l not prevent them from utilizir.g the f ive-mil e str etch of river below Melton Hill Dam.

In summary, for the typical or hypothetical extr eme summer cases ,

the thermal plume is so small th at adverse effects on striped bass would not be expected. Under extended no flow conditions, the avoidance of surface waters in the immediate area of th e discharge would not result in any significant adverse impacts.

In addition. TV A ' cur rent l y has studies underway at its Biothermal Research Station located at the Browns Ferry Nuclear Plant to determine l eth al temperatures for adult and juvenile striped bass under controlled field conditions in the experimental outdoor channel s at th is f acil ity. The preliminary results of th is study are expected to be available in late 1982, and will provide I4 Craven, T. M., D. L. Dycus, and D. A. Tomljanovich. 1982.

Responses of selected aquatic biota in Watts Bar Reservoi r to thermal di scharges f rom Ki ngston Steam-Electr ic Pl ant - 1978 and 1979. Draft report. Office of Natural Resources, Tennessee Val ley Author ity.

baseline Inf ormation on the temperature tolerance of striped bass which would be applicable to the CRBRP site as well as other power plant sites. It is expected th at the conclusion of th i s work will substantiate the above determination of no sign,1ficant impact to the striped bass f rom operation of CRBRP.

However, additional more definitive assessments of the thermal discharges are also being pursued by the Project which include:

(1) a statistical analysis of st r e am f l ow during the critical months of July through September; (2) a reecaluation of the thermal plume dispersion incorpor ati ng consi derati on "of the dis-charge into a strati f ied water body; and (3) a review of alterna-tive diffuser designs and two-dimensional modeling of the far field. This third step would be purpued only af ter consultation with TVA biologists if the results of the first two analyses indicate there is no suitable zone of passage for striped bass.

It is the Project's opinion that the results of the reeval uati on of the hydrodynam ics (incl uding al ternative di f f user designs, if necessary) and an' updated biological assessment, including the results from the biothermal research project study on striped bass, will show there is no substantive concern with respect to the impact of CRBRP operation on the striped bass fishery in Watts Bar Reservoir. Under th is cond iti on, there would be no need for str eam f l ow s f rom Mel ton H il l Dam to be al tered to assure protection of th e striped bass.

In the unlikely event th at al l of the above ef forts fall to show that CRBRP thermal discharge will have no signi f icant impact on the striped bass thermal ref uge, appropriate restrictions upon thermal discharge from the CRBRP during periods when the river water temperature is high and zero low conditions exist will be imposed.

Based on the above review of the Env ironmental Report analyses of the CRBRP thermal discharges and the Project's commitments to additional striped bass studies and adoption of restrictions upon thermal discharge during periods when the river water temperature is high and zero flow conditions exist, sufficient assurance i s prov ided that there wil l be no significant impact on striped bass ,

due to CRBRP thermal discharges. Therefore, the NRC concern with possible no flow conditions at the CRBRP site should not be a factor in determining whether another alternative site is environmentally preferable to the Clinch River site.

9

4.2 Protect Economics. Tec hng _l o g y . and Institutional Factors Section 4.1 addressed the first part of the Proposed Rul e's two-part analytical test requiring comparison of th e proposed site with alternative sites and concluded th at none of the ten alternative candidate sites is environmental ly pref erabl e to the Clinch River site. Notwithstanding the Section 4.1 findings, this section addresses the second part of the two-part analytical test that examines project economics, tecnnology, and Institu-tional factors. The important project eco n om i c , technology, and Institutional factors affected by the selection of the site f or the LMFBR Demonstrati on Pl ant are schedule impacts, Project cost, and util ity participation, all of which are discussed in the following subsections.

4.2.1 Schedgle Imaacts i n th e LMFBR Progr am Supplemental Environmental Impact Statement (DOE /EIS-0085-D) the timing objective for the LMFBR Demonstr ati on Plant (CRBRP) i s 'th at it should be completed as expeditiously as possible. Whil e th is objective can be met at the Clinch River site, a dec! !on to relocate the LMFBR Demonstration Plant at another site with in the TVA power service area would h ave the same schedule impact discussed in Environmental Report Appendix E for rel ocation to ei ther Hanf ord, Savannah River, or INEL, i.e.,

a bare minimum del ay of 33 months or a more probable delay of 43 month s or more starti ng f rom the time a decision was made to change sites. There are two basic sources of th is del ay:

1. The impact upon existing Project arrangements and authorizing legislation,15 and

2. The impact upon schedules f or the preparation of design -

and licensing inf ormation and issuance by NRC of an environmental statement and a site suitability report to reach today's stage of the CRBRP licensing process.

A detailed discussion of the basis for the 33 and 43 month delay estimates is provided in Appendix E of the Environmental Report (pages E-13 to E-19). The only difference to the Appendix E discussion f or relocation to a site outside the TV A system to a relocation to a site insi de th e TV A system is th at f or the limited purpose of th is analysis the assumption is made that TVA would still be willing to operate the plant as part of its system, buy the electric power generated by the olant, and possibly purchase the pl ant at the conclusion of th e demon-stration period, and th at the CRBRP Project Of f ice woul d not be relocated.

On the basis of a delay of th is magn i tude, it is clear th at relocation of the LMFBR Demonstration Plant to any alternative site within the TVA power service area would pr event accompl i sh-Ing the LMcBR program timing objective (i.e., constructing and operati ng an LMFBR Demonstr ati on Pl ant as expeditiously as possible).

15 1t should be noted that relocating the LMFBR Demonstration Plant with in the TVA power serv ice area woul d have the same impact on project arrangements and author izati on as rel ocati ng the LMFBR Demonstration Plant to the Hanford, Savannah River, or INEL sites because both the Project arrangements and author izati on speci f ical ly

, contemplate location of the project at the Clinch River site.

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4.2.2 Eroject Cost The Project has prepared a comparative cost analysis to identi fy the cost differences between l ocation of the LMFBR Demonstrati on Plant at the Clinch River site versus another alternative si te with in the TV A power serv!ce area. Because none of th e identified candidate sites within the TVA power servfce area was found to be environmentally preferable to the Clinch River site (see Section 4.1) there was no basis for considering any specific site in this cost analysis.

Instead, where the individual cost factors considered could potenti al ly be site speci f ic, a range of values was used so th at the total cost difference calculated would encompass any possible TVA al ternative site.

For this analysis October 1, 1982, was taken as time zero for computing the delay in the Project schedule due to rel ocati on. This is based on the assumption th at the NRC determination and the Project decisicn process woul d requi re until October 1, 1982, before the Project would accept the Clinch River sito as not licensable. The result of th e Pro'j ect 's co st analysis using the ref erence delay case of 43 months is presented in Table 3. Table 3 contains extensive f ootnotes th at Indicate the bases the Project used in calculating each line item of cost. As indicated in the footnotes 3, 10, and 12, minimal cost impact has been included for redesign, component or structural modifications, or reprocur ement co sts. The risk of increased costs in addition to those included in Table 3 resulting from rel ocati ng th e plant to an al ternative site is believed, however, to be high, especially considering the f act th at as of May 1982 th e CRBRP design was over 85% completed and $622.2 million worth of plant equipment had been ordered with $27 8.3 mil lion of th is equi pment already delivered.

TABLE 3 (

+

COST IMPACT OF RELOCATING CRBRP TO AN ALTERNATIVE TVA SITE - REFERENCE 43 MONTH DELAY CASE

?

/

i incremental Cost llam __5 (MIIIlon1

1. Escalation 601

2. Staff and Support Stretch Out 164

3. Equipment Procurement 7-36 4 Relocate Project Office 0

5. Additional Travri- 1

6. Difference in Prevailing Labor Rates 0-137

7. Site Studies - Other than Geological 1 j.

8. Site Studies - Geological 7

9. Site Work Package l'

10. Seismic 11-162

11. Foundation Materials and Walls /2l *

12. Site Adaptation Redesign 1 0 - B'8 ' "~

13. Excavation ' 0 14 ER Rework 1

15. PSAR Rework 1

16. Reduced Revenue from Sale of Power 0 TOTAL COST IMPACT - ADD 809-1210*

• This range of additional cost cannot be obtained.by simply adding the minimum or maximum values respectively from"the above line items. Each line item's range of incremental cost has been estimated to encompass the variety of potential TVA alternative sites and, where some TVA alternative sites may account for the maximum range for one item, they may represent the minimum range for another line item (e.g.,

alternative sites in northeastern Tennessee represent the maximum i nc r em e n t a l cost for equipment procurement because of their lack of barge capabilities, but represent the minimum for difference in prevailing labor rates).

N f ,w L

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Notes for resoective line items in Tahle 3

1. Escal ati on The $601M escala. tion cost was calculated using an 8%

escalation rate based on the following:

-Base case total plant cost $3.2B

-Cost through October 1, 1982 $1.3B

-Ccst to go as of October 1, 1982 31.9B

2. Staff and Support Stretch Out The cost of staff and support str etch out is summarized

, a s . f o l l o,w s : .

-Project Office 3 25M

-Reactor Manufacture $111M

-Architect Engineer 3 19M

-Construction 5-.9M

$164M

3. Equ i pment Procur ement includes costs for continued stor age, crating and reloading, and transportati on of al ready del ivered components, and differences in tr ansportation costs f or all components not yet del ivered. No costs are included f or any equipment components that may have to be repurchased or modified because of changes in engl-neering speci f ications due to the change in site.

4. Relocate Project Office it is assumed th at the existi ng CRBR? PO woul d be maintained in Oak Ridge for all al ternative TV A sites.

Notes for Table 3 (Contidl

5. Additione. Travel Based on a minimum estimate of changes in commuting costs compared to actual expenditures at Oak Ridge.

6. Olfference in Prevailing Labor Rates 4

At any al ternative TV A site, except those in north-

- eastern Tennessee, the increase in local labor costs compared to the base case at the Clinch River site range from $56-137 million. The basis f or th is estimate started with the scope of work and total manhours required to construct CRBRP. Using the work scope, an average wage was calculated by wei ghti ng each craf t's local labor rate by its percentage of the work for different l oca ti on s in the TVA power service area.

Comparisons were then made against an Oak Ridge average and the' increase calculated according to the man hours required to construct the CRBRP.

7. Site Studies - Other than Geological Based on actual expenditures for speci f ic tasks th at have already been performed. Dollars shown are only for tasks where work is not transf erable to an al ternative site.

8. Site Studies - Geological See note for item 7.

i Epig d gr TabIe 3 (Cont!di O

9. Site Work Package See note for item 7.

10. Seismic At any alternative site even if the SSE and OBE were the' same as at the Clinch River site, differences in the seismic response spectra would require the reanalysis of structures and components. Because much of the cost of the original analysis was for component modeling which does not need to be redone, 10% of the total actual expenditures made between 1974 and July 1, 1981, was estimated as the minimum cost for required seismic reanalysis. It should be noted that since seismic design parameters are site-specific, a new seismic model woul d have to be oeveloped for each site. Because the resul ti ng si te-speci f ic sei smic response spectr a coul d be more severe than the CRBRP design basis f or some components, these components coul d have to be redesigned or, if the component has al ready been ordered or delivered, it may require modification, or may have to be scrapped and repurchased. None of these potenti al redesign, component modi f icati on, or reprocurement costs have been included in the 511M estimate.

i j 11. Foundation Material s and Wal l s l

As with item 10, all alternative sites would require reanalysis of the foundation materials and walls. The

$2M estimate is a minimum estimate considering only the expected reana lysi s costs.

. i e

Notes for Table 3 (Cont'dl

12. Site Adaptation Redesign At any al ternative site, plant building and site development, roads, railroads, uti l i ty sy stems, sewer and dr ai nage sy stems, etc., would need redesign. This additional cost was assumed to be 25% of all structural design-rel ated work and 25% Ef all site design-rel ated work based on actual expenditures between 1974 and July 1, 1981. As was noted in item 10, the site specific seismic model or other site speci f ic geologic f actors could require redesign of the plant foundations and walls. None of these costs have been included in the

$10M.

13. Exc av ati on The Clinch River site rock depth equals 50 feet whereas at certsin of the TV A al ternative sites exam ined the estimated rock depth was as sh al low as 30 feet. Using a cost of $15/ cubic yard and the additional amount to be excavated (600,000 c.y.), the maximum additional excavation cost is $6M.

14. Environmental Report Rework Minimum estimate based on the amount of material to be modified, updated, or verified.

15. Prel iminary Saf ety Analysis Report Rework

[

l See note for item 14.

16. Reduced Revenue from Sale of Power it i s assumed th at the revenue from the sale of power dur ing the demonstr ati on per iod wou l d r emai n unc h an ge d .

i 1

This substantially higher risk of design changes should the CRBRP be relocated would require a higher contingency in the total Project cost estimate. Therefore, the actual incremental cost increase for an alternative TVA site could be several hundreds of millions of dol lars more th an the 5809-1210 million shown in Table 3.

In summary, taking the current Project cost of $3.2 billion as a base, the cost of the same project at an alternative site within the TVA power service area would be higher than at the Clinch River tte by a mnimum of $809-1210 million for the reference 43 month delay case. Even this minimum cost assessment viv idly il l ustrates the dr amati c Increase in project cost for an alternative site compared to the Clinch River site.

4.2.3. Utllity ParticIRA112H As mentioned in Section 4.2.1 above, if the LMFBR Damonstration Plant were to be built somewhere on the TVA power system other than at the Clinch River site, the assumption has been made for the limited purposes of this report that a site would be available and that TVA would agree to continue in the same role it now has at the Clinch River site. Thus, the LMFBR program objective of utility participation would be satisfied for any selected site within the TVA power service area.

+ o 4.3 Cgnclusion The Project has caref ul ly reexam ined and reanalyzed the com-parison of the proposed Clinch River site with the ten alter-native candidate sites identified in Section 3.0 in accordance with the Proposed Rule's sequential two-part test. Of the ten alternative candidate sites, nine were prevlously candidate sites in the siting assessment presented in Environmental Report Section 9.2 and Appendix A with the tenth site, Yellow Creek, being added to represent sites in TVA's western area (see Section 3.0). The conclusion reached in Section 4.1 concerning the required comparison of these sites with primary consideration given to environmental f actors was that none of 'the ten alternative candidate sites are environmentally preferable to the Clinch River site. While this finding from part one of the Proposed Rule's two-part test woula not require any additional determination on project economic, technology, and institutional factors (i.e., part two of the Proposed Rule's two-part test),

the Project nevertheless presented in Section 4.2 a discussion of Project schedule'and cost impacts that are site dependent. In Section 4.2 it was shown that a substantial increase in Project cost (a minimum of $809 - 1210 million) and a reference schedule delay of 43 months that would prevent satisfaction of the LMFBR program timing objective of constructing and operating an LMFBR Demonstration Plant as expeditiously as possible would result from relocating the CRBRP. These findings, independent of the conclusion in Section 4.1 on environmental preferability, lead to a determination that no obviously superior site exists. Thus, the Project has acceptably demonstrated in accordance with the requirements of the Proposed Rule that the Clinch River site is the preferred site for the LMFBR Demonstration Plant and that no obviously superior site exists.

. o 5.0

SUMMARY

AND CONCLUSIONS At the request of the NRC, the Project has provided this update to the original CRBRP siting assessment provided in CRBRP Environmental Report Section 9.2 and Appendix A. This update, using appropriate current information, has shown that in accord-ance with the NRC Proposed Rule on Alternative Sites, (1) the TVA power service area is an appropriate " region of interest" (Section 2.0), (2) prevlously consi dered al ternative sites constitute a sufficient number of candidate sites which meet the threshold criteria and reasonably represent the environmental diversity in the TVA power service area (Section 3.0), and (3) none of the ten al ternative candi date sites identified in Section 3.0 are environmental ly pref erable to the Clinch River site .

(Section 4.1). Fur th erm or e, the discussions in Section 4.2 show th at there would be substantially increased project costs at another TV A site and th at th e LMFBR progr am timing objective could not be met at any al ternative TV A site. When these Project economic and i n st i tut t oria l f actors are added to the f indings concerning environmental preferability, it is clear th at no obviously superior site exists in the TVA power service area for l ocati ng the LMFBR Demonstr ati on Pl ant. Theref ore, the Project concludes th at the proposed Clinch River site remains the preferred site for the LMFBR Demonstr ati on Pl ant.

I

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APPENDIX X -

PROPOSED SURVEY OF FRESHWATER MUSSELS IN THE Y ICl N ITY OF THE CRBRP ,S I TE l

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PROPOSED SURVEY OF FRESHW ATER MUSSELS IN THE VICIN'TY OF THE CRBRP SITE I. Ggneral Survev Phgsg AT stations l ocated every 0.2 mil e between Clinch River Mil e (CRM) 14.0 and CRM 18.0, scuba divers wIll search for mussels along ropes laid across the full width of the river. At each station, data col lected w il l include the number of each mussel species found in each 20-foot i n t erv a l , observations on substrate composition, and a depth prof il e, ll. Mussel Haaltat Assessmgnt Pha13 I f mor e th an f ive musse l soecles are found in a 40-foot survey segment (two adjacent 20-foot intervals) or if one or more ingcimens of an endangered species is found in a 20-foot survey interval, th e following, more Intensive technique will be initiated. This detailed search ph ase is expected to be i n i t i ated r'ath er r arel y in the CRBRP reach of the Clinch River and, if more th an four such investigations are warranted, the initiating criteria wilI be evaluated in light of the data being acquired.

Scuba divers will conduct a 15-minute se arch for mussels l parallel to river flow starting 0.1 mil e downstr eam from th e j general survey Interval that initi ated th is assessment. If l f ive or more mussel soecles are found during th is dive, a second 15-minute dive will be made with in the same substrate habitat type at the site. If the second dive yleids one or more additional species, a th ird and, if simil arl y indicated, a fourth dive will be made in the suitable habitat at the site. The minimum search ef f ort f or th is Intensive phase at one site would be one 15-minute dive. The maximum effort for l one site which could be Indicated would be four 15-minute dives. ,

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e Data from each dive will be maintained separately and will include tne location of th e div e, the number of each mussel species found, comments on substr ate conditions, and depth

. prof fl ee Field notes, narrative, and tabular summaries of all data will be supplied to the assessment staff for revlew and tabu l ati on.

A full repor,t,, covering the survey and its eval uation w il l be prepared and'I p rovided to the CRBRP staff for possible transmittal to the Nucl ear Regul atory Commission and other appropr iate regu l atory agenc ies.

9

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