ML12276A375

Watts Bar, Units 1 and 2, Notification of Completion of Review of Updated Hydrologic Analysis Results for Impact on Watts Bar Nuclear Plant (WBN) Units 1 and 2 Final Environmental Statements

ML12276A375
Person / Time
Site:	Watts Bar
Issue date:	10/01/2012
From:	Shea J W Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
TAC ME8200
Download: ML12276A375 (8)

Text

Tennessee Valley Authority, 1101 Market Street, Chattanooga, Tennessee 37402October 1, 201210 CFR 50.410 CFR 50.34(b)ATTN: Document Control DeskU.S. Nuclear Regulatory CommissionWashington, D.C. 20555-0001Watts Bar Nuclear Plant, Unit 1NRC Docket No. 50-390Facility Operating License No. NPF-90Watts Bar Nuclear Plant, Unit 2NRC Docket No.50-391Subject: Notification of Completion of Review of Updated Hydrologic AnalysisResults for Impact on Watts Bar Nuclear Plant (WBN) Units 1 and 2 FinalEnvironmental StatementsReferences: 1. Tennessee Valley Authority (TVA) Submittal to NRC Document ControlDesk, Application to Revise Watts Bar Nuclear Plant Unit 1 Updated FinalSafety Analysis Report Regarding Changes to Hydrologic Analysis,TAC No. ME8200 (WBN-UFSAR-12-01), dated July 19, 2012, AccessionNo. ML12236A1672. NUREG-0498, Supplement No. 1, Final Environmental Statement Relatedto the Operation of Watts Bar Nuclear Plant, Units 1 and 2, November 1994,Accession No. ML0734705853. NUREG-0498, Supplement No. 2, Draft Final Environmental StatementRelated to the Operation of Watts Bar Nuclear Plant, Unit 2, October 2011,Accession Nos. ML1 1298A094 and ML1 1298A095As committed to in the Reference 1 letter, Tennessee Valley Authority (TVA) has reviewed theReference 2 Final Environmental Statement (1994 FES) and Reference 3 Draft FinalEnvironmental Statement (2011 FES) for impact resulting from the revised hydrologic analysisfor the Watts Bar Nuclear Plant (WBN) Units 1 and 2 sites. The 1994 FES and 2011 FESdescribe the surface water resources and hydrologic processes in and around the WBN siteincluding existing water use and water quality in the environment in the vicinity of WBN Units 1and 2. These descriptions of the affected environment for WBN Units 1 and 2 include citingrecent information from TVA, and were not expected to be affected by the updated hydrologicanalysis. TVA has reviewed the information contained in the updated hydrologic analysis, andhas determined that the information provided in the 1994 FES and 2011 FES is not affected.The results of this review are described in Enclosures 1 and 2, respectively.Printed on recycled paper " ,9 12 U.S. Nuclear Regulatory CommissionPage 2October 1, 2012The commitment due date provided in the Reference 1 letter was September 30, 2012. Sincethis was a Sunday, TVA is submitting this letter on October 1, 2012.The enclosures contain no new regulatory commitments. Please address any questionsregarding this request to Terry Cribbe at (423) 751-3850.J.W. SheaVice President, Nuclear icensingEnclosures:1. Impact of Revised Hydrologic Analysis on WBN Units 1 and 2 Final EnvironmentalStatement (1994 FES)2. Impact of Revised Hydrologic Analysis on WBN Unit 2 Draft Final EnvironmentalStatement (2011 FES)cc (Enclosure):NRC Regional Administrator -Region IINRC Senior Resident Inspector -Watts Bar Nuclear Plant, Unit 1NRC Senior Resident Inspector -Watts Bar Nuclear Plant, Unit 2 ENCLOSUREIIMPACT OF REVISED HYDROLOGIC ANALYSIS ONWBN UNITS I AND 2 FINAL ENVIRONMENTAL STATEMENT (1994 FES)The original Final Environmental Statement issued in 1978 (1978 FES) represented theNuclear Regulatory Commission's (NRC) previous environmental review related to theproposed operation of Watts Bar Nuclear Plant (WBN). In the early 1990's, the NRCdetermined that it was appropriate to re-examine the issues associated with the environmentalreview before issuance of an operating license for WBN Unit 1. The purpose of this NRCreview was to discuss the effects of observed changes in the environment and to evaluate thechanges in environmental impacts that have occurred as a result of changes in the WBN plantdesign and proposed methods of operations since the last environmental review. A full scopeof environmental topics were evaluated, including regional demography, land and water use,meteorology, terrestrial and aquatic ecology, radiological and non-radiological impacts onhumans and the environment, socioeconomic impacts, and environmental justice.NUREG-0498, Supplement No. 1, Final Environmental Statement Related to the Operation ofWatts Bar Nuclear Plant, Units 1 and 2, November 1994, Accession No. ML073470585,documents the staff's environmental review. This document is referred to as the WBN Units 1and 2 Final Environmental Statement (1994 FES). The staff concluded in the 1994 FES thatthere were no significant changes in the environmental impacts since the NRC 1978 FES fromchanges in plant design, proposed methods of operations, or changes in the environment.Since issuance of the 1994 FES, the Tennessee Valley Authority (TVA) has updated thehydrologic analysis for the WBN Units 1 and 2 site. The update of the hydrologic analysisincludes, but is not limited to, the following:" Changes to the description of the current hydrosphere," Use of more recent flood history information,* Changes to the inputs used for determining probable maximum precipitation (PMP),* Changes to the probable maximum flood (PMF) and design basis flood (DBF) elevations atthe plant site,* Changes to the runoff and stream course model,* Changes to the determination of seismically induced dam failure flood impacts at the plantsite,* Changes to the analysis for determining that adequate water is available for operation ofWBN Units 1 and 2, and* Updates to flooding protection requirements.The update to the runoff and stream course model includes updated discharge rating curves toaddress recently identified rim leaks for Fort Loudoun Reservoir and Watts Bar Reservoirwhich result in bypass flow around the respective dams. As a result of the issues and updatesassociated with the hydrologic analysis, the PMF elevation at the WBN site is increased fromelevation 734.9 ft to 739.2 ft, and the resulting DBF elevations affecting the safety-relatedsystems, structures, and components (SSCs) are increased. Most of the SSCs that arePage 1 of 3 ENCLOSURE1IMPACT OF REVISED HYDROLOGIC ANALYSIS ONWBN UNITS I AND 2 FINAL ENVIRONMENTAL STATEMENT (1994 FES)required to be protected from a flood are not impacted by the increased DBF elevations,because margin remains between the DBF elevations and the elevations of the SSCs or theexisting flood protection measures are still effective. However, there are exceptions thatrequire temporary compensatory measures to ensure adequate flood protection in the interim,with permanent plant modifications planned to restore or gain additional margin between therevised DBF elevations and the elevations of the limiting safety-related SSCs.In Section 2.2 of the 1994 FES, a description of the regional water use (Section 2.2.1), thechanges in the surface water hydrology of the plant (Section 2.2.2), and changes in the waterquality (Section 2.2.3) are discussed. The impact of the revised hydrologic analysis includingupdate to the methodology for determining PMF and DBF elevations at the plant as well asrevision of the PMF and DBF elevations themselves is described for each correspondingsection in the following discussions.2.2.1 Regional Water UseRegional water use by the downstream users of both public and industrial water supplieswithin an 80-kilometer (50-mile) radius of the plant, and the water's travel time and dilutionfactor for these users, are discussed in this subsection of the 1994 FES. The latestinformation identifying the water users is provided in Table 2.5, which is based on the letterfrom D. E. Nunn, TVA, to U.S. NRC, Watts Bar Nuclear Plant (WBN) Units 1 and 2 -Requestfor Additional Information Related to the Environmental Review, dated November 4, 1994(Accession No. ML073470438). The information and analyses in this section were notsignificantly changed in the 1994 FES from that discussed in the 1978 FES. The informationpresented in the 1994 FES remains accurately described and is not impacted by the revisedhydrologic analysis.TVA has confirmed that the discussions involving regional water use and the summary inTable 2.5, including the cited supporting documentation, require no revision as a result of theupdated hydrologic analysis. Therefore, there is no impact warranting further NRC review ofthis section of the 1994 FES.2.2.2 Surface Water HydrologySurface water hydrology is discussed in this subsection of the 1994 FES, includingdescriptions of the holding and evaporation/percolation ponds on the WBN site, discussionsconcerning the approvals by the State of Tennessee of site controls for the monitoring of theponds as evident from the issuance of the National Pollution Discharge Elimination System(NPDES) permit in 1993, and controls for handling storm water including erosion andsedimentation controls. The latest information supporting these discussions is based on theTVA report, Watts Bar Groundwater Impacts of Evaporation/Percolation Pond, WR28-1-85-133, dated July 1990; the 1993 State of Tennessee NPDES permit; and the letter from D. E.Nunn, TVA, to U.S. NRC, Watts Bar Nuclear Plant (WBN) Units 1 and 2 -Request forAdditional Information Relating to Final Environmental Statement, dated August 5, 1994(Accession No. ML073470403). The information and analyses in this section were updated inthe 1994 FES from that discussed in the 1978 FES, primarily to address the following areas:Page 2 of 3 ENCLOSUREIIMPACT OF REVISED HYDROLOGIC ANALYSIS ONWBN UNITS 1 AND 2 FINAL ENVIRONMENTAL STATEMENT (1994 FES)1. The two temporary chemical holding ponds discussed in the 1978 FES were retained aspermanent features, and are still being used to contain and treat chemicals from theturbine building. The discharges from these ponds were being monitored in accordancewith the NPDES permit for metal cleaning wastes.2. A 2.5 million gallon evaporation/percolation pond was constructed after issuance of the1978 FES and approved by the State of Tennessee in the 1993 NPDES permit. The1994 FES stated that TVA planned to eventually discontinue use of the pond and thenwould cap and revegetate the area.3. The runoff holding pond that was originally built for construction discussed in the 1978 FESwas retained as a permanent feature. The discharge from the pond was being monitoredin accordance with the NPDES permit.4. As discussed in the 1978 FES, all point source discharges and storm water runoff pointswere being monitored in accordance with the NPDES permit. Under the general stormwater permit for industrial sources, all requirements for erosion and sedimentation controls(i.e., inspections, corrective actions, and annual sampling) were implemented at WBN. Inaddition, biotoxicity sampling was being conducted semiannually at the main diffuserdischarge and the runoff holding pond in accordance with the NPDES permit. The1994 FES confirmed this information.The information presented in the 1994 FES remains accurately described and is not impactedby the revised hydrologic analysis.TVA has confirmed that the discussions involving surface water hydrology on the site,including the cited supporting documentation, require no revision as a result of the updatedhydrologic analysis. Therefore, there is no impact warranting further NRC review of thissection of the 1.994 FES.2.3.3 Water QualityInformation and analyses of water quality in the Tennessee River in the vicinity of the WBNplant are discussed in this subsection of the 1994 FES. In the letter from D. E. Nunn, TVA, toU.S. NRC, Watts Bar Nuclear Plant (WBN) Units 1 and 2 -Request for Additional InformationRelating to Final Environmental Statement, dated August 5, 1994 (AccessionNo. ML073470403), TVA confirmed that the information and analyses of water quality had notsignificantly changed from that discussed in the 1978 FES, and the NRC agreed in the1994 FES. The information presented in the 1994 FES remains accurately described and isnot impacted by the revised hydrologic analysis.TVA has confirmed that information and analyses of water quality, including the citedsupporting documentation, require no revision as a result of the updated hydrologic analysis.Therefore, there is no impact warranting further NRC review of this section of the 1994 FES.Page 3 of 3 ENCLOSURE2IMPACT OF REVISED HYDROLOGIC ANALYSIS ONWBN UNIT 2 DRAFT FINAL ENVIRONMENTAL STATEMENT (2011 FES)On March 4, 2009, TVA submitted an update to the NRC regarding the previously submittedapplication for a facility operating license to possess, use, and operate WBN Unit 2. The NRCpublished the notice of the receipt of application and the opportunity for hearing in the FederalRegister on May 1, 2009. The NRC's regulations in Title 10 of the Code of FederalRegulations (10 CFR) 51.92, Supplement to the Final Environmental Impact Statement,require the NRC staff to prepare a supplement to the final environmental statement if there aresubstantial changes in the proposed action relevant to environmental concerns or if there aresignificant new circumstances or information relevant to environmental concerns bearing onthe proposed action or its impacts. The same regulation permits the staff to prepare asupplement when, in its opinion, preparation of a supplement will further the interests of theNational Environmental Policy Act of 1969. NUREG-0498, Supplement No. 2, Draft FinalEnvironmental Statement Related to the Operation of Watts Bar Nuclear Plant, Unit 2,October 2011, Accession Nos. ML1 1298A094 and ML1 1298A095, documents the staff'senvironmental review. This document is referred to as the WBN Unit 2 Draft FinalEnvironmental Statement (2011 FES). The staff concluded in the 2011 FES that impacts fromthe operation of WBN Unit 2 associated with water use, terrestrial resources, aquatic ecology,design-basis accidents, socioeconomics, the radiological and nonradiological environments,decommissioning, air quality, and land use are generally consistent with those reached in the1978 FES and Supplement No. 1 to the Final Environmental Statement Related to theOperation of Watts Bar Nuclear Plant, Units 1 and 2, dated April 1995 (1995 SFES-OL-1). Insome cases, the impacts were less than those identified in the 1978 FES.Since the issuance of the 2011 FES, TVA has updated the hydrologic analysis for the WBNUnits 1 and 2 site. The update of the hydrologic analysis includes, but is not limited to, thefollowing:* Changes to the description of the current hydrosphere," Use of more recent flood history information," Changes to the inputs used for determining PMP,* Changes to the PMF and DBF elevations at the plant site,* Changes to the runoff and stream course model," Changes to the determination of seismically induced dam failure flood impacts at theplant site,* Changes to the analysis for determining that adequate water is available for operationof WBN Units 1 and 2, and* Updates to flooding protection requirements.The update to the runoff and stream course model includes updated discharge rating curves toaddress recently identified rim leaks for Fort Loudoun Reservoir and Watts Bar Reservoirwhich result in bypass flow around the respective dams. As a result of the issues and updatesPage 1 of 3 ENCLOSURE2IMPACT OF REVISED HYDROLOGIC ANALYSIS ONWBN UNIT 2 DRAFT FINAL ENVIRONMENTAL STATEMENT (2011 FES)associated with the hydrologic analysis, the PMF elevation at the WBN site is increased fromelevation 734.9 ft to 739.2 ft, and the resulting DBF elevations affecting the safety-relatedSSCs are increased. Most of the SSCs that are required to be protected from a flood are notimpacted by the increased DBF elevations, because margin remains between the DBFelevations and the elevations of the SSCs or the existing flood protection measures are stilleffective. However, there are exceptions that require temporary compensatory measures toensure adequate flood protection in the interim, with permanent plant modifications planned torestore or gain additional margin between the revised DBF elevations and the elevations of thelimiting safety-related SSCs.These updates have been addressed in the Final Safety Analysis Report (FSAR) portion of theapplication for an operating license for WBN Unit 2 (Reference: Letter from Raymond A.Hruby, Jr. (Watts Bar Unit 2, General Manager, Technical Services) to U.S. NRC datedAugust 23, 2012, Watts Bar Nuclear Plant (WBN) Unit 2 -Final Safety Analysis Report(FSAR), Amendment 109, Accession No. ML12244A018).In Section 2.2 of the 2011 FES, a description of the surface water hydrology (Section 2.2.1.1),regional water use (Section 2.2.2.1), and surface water quality (Section 2.2.3.1) are discussed.The impact of the revised hydrologic analysis including update to the methodology fordetermining PMF and DBF elevations at the plant as well as revision of the PMF and DBFelevations themselves is described for each corresponding section in the followingdiscussions.2.2.1.1 Surface Water HydrologySurface water hydrology is discussed in this subsection of the 2011 FES, including changes inthe operations of the reservoirs on the Tennessee River upstream of WBN Unit 2 by TVARiver Operations (RO) since issuance of the 1995 SFES-OL-1. The changes discussed arefor the Watts Bar and Chickamauga reservoirs as a result of a Reservoir Operations Study(ROS) completed in 2004 (Reference: Reservoir Operations Study Final ProgrammaticEnvironmental Impact Statement, Tennessee Valley Authority in cooperation with U.S. ArmyCorps of Engineers and U.S. Fish and Wildlife Service, Accession Nos. ML041100586,ML041100585, ML041100590, ML041100588), with information regarding the physicalcharacteristics of these reservoirs from the ROS presented in Table 2-2. The informationpresented in the 2011 FES remains accurately described and is not impacted by the revisedhydrologic analysis.Also discussed in this subsection is TVA's renewal application for the NPDES permit in 2006(Reference: Letter from J.D. Smith (Manager, Site Licensing and Industry Affairs (Acting),TVA) to U.S. NRC dated December 19, 2006, Watts Bar Nuclear Plant (WBN) Unit 1 -Notification of National Pollution Discharge Elimination (NPDES) Permit Renewal, AccessionNo. ML063560378). This renewal application updates the 1993 State of Tennessee NPDESpermit cited in the 1995 SFES-OL-1, and remains accurately described in the 2011 FES and isnot impacted by the revised hydrologic analysis.Page 2 of 3 ENCLOSURE2IMPACT OF REVISED HYDROLOGIC ANALYSIS ONWBN UNIT 2 DRAFT FINAL ENVIRONMENTAL STATEMENT (2011 FES)TVA has confirmed that the discussions involving surface water hydrology, including the citedsupporting documentation, require no revision as a result of the updated hydrologic analysis.Therefore, there is no impact warranting further NRC review of this section of the 2011 FES.2.2.2.1 Regional Water UseRegional water use by the downstream users of both public and industrial water supplieswithin an 80-kilometer (50-mile) radius of the plant, and the water's travel time and dilutionfactor for these users, are discussed in this subsection of the 2011 FES. Since the issuanceof the 1995 SFES-OL-1, TVA provided updated information regarding downstream water usersin 2010 (Reference: Letter from Masoud Bajestani (Watts Bar Unit 2, Vice President) to U.S.NRC dated February 25, 2010, Watts Bar Nuclear Plant (WBN) Unit 2 -Additional InformationRegarding Environmental Review (TAC No. MD8203), Accession No. ML100630115), asaddressed in the 2011 FES. In addition, as part of the most recent update to the WBN Unit 2FSAR portion of the application for an operating license (Reference: Letter from Raymond A.Hruby, Jr. (Watts Bar Unit 2, General Manager, Technical Services) to U.S. NRC dated August23, 2012, Watts Bar Nuclear Plant (WBN) Unit 2 -Final Safety Analysis Report (FSAR),Amendment 109, Accession No. ML12244A018), TVA has provided the most recent regionalwater use information. The information presented in the 2011 FES remains accuratelydescribed and is not impacted by the revised hydrologic analysis.TVA has confirmed that the discussions involving regional water use, including the citedsupporting documentation, require no revision as a result of the updated hydrologic analysis.Therefore, there is no impact warranting further NRC review of this section of the 2011 FES.2.2.3.1 Surface Water QualityInformation and analyses of surface water quality in the Tennessee River in the vicinity of theWBN plant are discussed in this subsection of the 2011 FES. As stated in the 2011 FES, inresponse to Requests for Additional Information (RAls) for the environmental review, TVAprovided analyses performed between January 2006 and December 2008. The results fellwithin the range previously observed (Reference: Letter from Masoud Bajestani (Watts BarUnit 2, Vice President) to U.S. NRC dated December 23, 2009, Watts Bar Nuclear Plant(WBN) Unit 2 -Additional Information Regarding Environmental Review (TAC No. MD8203),Accession No. ML1 00210350). The information presented in the 2011 FES remainsaccurately described and is not impacted by the revised hydrologic analysis.TVA has confirmed that the discussions involving surface water quality, including the citedsupporting documentation, require no revision as a result of the updated hydrologic analysis.Therefore, there is no impact warranting further NRC review of this section of the 2011 FES.Page 3 of 3