NUREG-0498 Supplement No. 1 Final Environmental Statement related to the operation of Watts Bar Nuclear Plant, Units 1 and 2 Docket Nos. 50-390 and 50-391 Tennessee Valley Authority U.S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation April 1995 Q%''Ve,,° AVAILABILITY NOTICE Availability of Reference Materials Cited in NRC Publications Most documents cited in NRC publications will be available from one of the following sources: 1. The NRC Public Document Room, 2120 L Street, NW., Lower Level, Washington, DC 20555-0001 2.. The Superintendent of Documents, U.S. Government Printing Office, P. 0. Box 37082, Washington, DC 20402-9328 3. The National Technical Information Service, Springfield, VA 22161-0002 Although the listing that follows represents the majority of documents cited in NRC publica- tions, it is not intended to be exhaustive. 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Copies of industry codes and standards used in a substantive manner in the NRC regulatory process are maintained at the NRC Library, Two White Flint North, 11545 Rockville Pike, Rock- ville, MD 20852-2738, for use by the public. Codes and standards are usually copyrighted and may be purchased from the originating organization or, if they are American National Standards, from the American National Standards Institute, 1430 Broadway, New York, NY 10018-3308. NUREG-0498 Supplement No. I Final Environmental Statement related to the operation of Watts Bar Nuclear Plant, Units 1 and 2 Docket Nos. 50-390 and 50-391 Tennessee Valley Authority U.S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation April 1995 Abstract The Final Environmental Statement-Operating License (FES-OL) issued in 1978 represents the Nuclear Regula- tory Commission's (NRC's) previous environmental review related to the operation of Watts Bar Nuclear (WBN) Plant. The NRC staff has determined that it is appropriate to re-examine the issues associated with the environmental review before issuance of an operating license. The purpose of this NRC review is to discuss the effects of observed changes in the environment and to evaluate the changes in environmental impacts that have occurred as a result of changes in the WBN Plant design and proposed methods of operations since the last environmental review. A full scope of environmental topics has been evaluated, including regional demo- graphy, land and water use, meteorology, terrestrial and aquatic ecology, radiological and non-radiological impacts on humans and the environment, socioeconomic impacts, and environmental justice. The staff con- cluded that there are no significant changes in the environmental impacts since the NRC 1978 FES-OL from changes in plant design, proposed methods of operations, or changes in the environment. The Tennessee Valley Authority's (TVA's) preoperational and operational monitoring programs were reviewed and found to be appropriate for establishing baseline conditions and ongoing assessments of environmental impacts. The staff also conducted an analysis of plant operation with severe accident mitigation design alternatives (SAMDAs) and concluded that none of the SAMDAs, beyond the three procedural changes that the TVA com- mitted to implement, would be cost-beneficial for further mitigating environmental impacts. April 1995 i°° NUREG-0498, Supp. 1 Contents, Abstract ........... Foreword .......... xv D efinitions ............................ ........... xvii Abbreviations/Acronyms ................... ........... xxv Summary and Conclusions .................. ........... xxix I Introduction ....................... ........... 1-1 1.1 H istory ....................... ........... 1-1 1.2 Environmental Approvals and Consultations. ........... 1-4 1.3 References ...................... ........... 1-5 2 The Site ........... 2-1 2.1 Regional Demography .............. ........... 2-1 2.1.1 Population Changes ........... ........... 2-1 2.1.2 Changes in Regional Socioeconomic Characteristics 2-1 2.2 W ater Use ...................... ........... 2-9 2.2.1 Regional Water Use .......... ........... 2-9 2.2.2 Surface Water Hydrology ....... ........... 2-9 2.2.3 Water Quality .............. ........... 2-11 2.3 Meteorology ..................... ........... 2-16 2.3.1 Regional Climate ............ ........... 2-16 2.3.2 Severe Weather ............. ........... 2-16 2.3.3 Local Meteorological Conditions . ........... 2-17 2.3.4 Atmospheric Dispersion ........ ........... 2-18 2.4 Ecology ........................ ........... 2-19 2.4.1 Terrestrial Ecology ........... ........... 2-19 2.4.2 Aquatic Ecology ............. ........... 2-22 April 1995 V NUREG-0498, Supp. 1 Page 2.5 Background Radiological Characteristics.................................... 2-28 2.6 Historical and Archeological Sites .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .... 2-30 2.7 Geology and Seismology .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .... 2-31 2.8 References .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ...... 2-31 3 The Plant.. .. ... .. .. .. .. .. .. .. .... .. .. .. .. .. .. .. .. .. .. .. .. .. .. ..... 3-1 3.1 Plant Water Use .. .. .. .. ... .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .... 3-1 3.2 Heat Dissipation Systems.............................................. 3-1 3.3 Radioactive Waste Treatment System...................................... 3-2 3.4 Chemical, Sanitary, and Other Waste Treatment............................... 3-3 3.5 Power Transmission System............................................ 3-7 3.6 References....................................................... 3-7 4 Environmental Effects of Site Preparation and Plant and Transmission Facilities Construction ... 4-1 4. 1 References....................................................... 4-1 5 Environmental Impact of Watts Bar Nuclear Plant and Transmission Facilities Operations ... 5-1 5.1 Impacts on Land Use................................................ 5-1 5.2 Impacts on Water Use................................................ .5-2 5.2.1 Thermal Discharges........................................... 5-2 5.2.2 Operational Chemical Wastes..................................... 5-2 5.2.3 Sanitary Wastes.............................................. 5-3 5.2.4 NPDES Permit.............................................. 5-3 5.2.5 Effects on Water Users Through Changes in Water Quality..................5-3 5.2.6 Effects on Surface Water Supply................................... 5-3 5.2.7 Effects on Groundwater......................................... 5-4 5.2.8 River Recreational Use......................................... 5-4 5.3 Impacts on Terrestrial Environment....................................... 5-4 5.3.1 Impacts on Terrestrial Animal Species................................ 5-4 5.3.2 Impacts on Terrestrial Plant Species................................. 5-5 5.3.3 Impacts on Threatened and Endangered Terrestrial Species ................... 5-6 5.4 Impacts on Aquatic Environment......................................... 5-7 5.4.1 Entrainment and Impingement of Aquatic Biota.......................... 5-7 5.4.2 Thermal Effects.............................................. 5-7 5.4.3 Chemical Effects............................................. 5-8 NUREG-0498, Supp. 1IiArl19 vi April 1995 Page 5.4.4 Impacts on Threatened and Endangered Aquatic Species....................5-9 5.4.5 Nuisance Aquatic Organisms...................................... 5-10 5.5 Radiological Impacts................................................. 5-11 5.5.1 Changes to the Plant........................................... 5-11 5.5.2 Summary of Radioactive Effluents and Potential Exposures of Humans........... 5-11 5.5.3 Radiological Impact on Animals................ .................... 5-16 5.5.4 Storage and