Generic Environmental Impact Statement forLicense Renewal of Nuclear Plants: Main Report (NUREG-1437, Volume 1)

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• Publication Information
• Table of Contents
• Abstract

Publication Information

Manuscript Completed: April 1996
Date Published: May 1996

Division of Regulatory Applications
Office of Nuclear Regulatory Research
U.S. Nuclear Regulatory Commission
Washington, DC 20555-0001

Availability Notice

Table of Contents

•  
  • Abstract
  • Figures
  • Acronyms and Abbreviations
  • Executive Summary
    • Impacts of Refurbishment
    • Impacts of Operation
    • Accidents
    • Uranium Fuel Cycle and Management of Waste
    • Decommissioning
  • 1. Introduction
    • 1.1 Purpose of the GEIS
    • 1.2 Renewal of a Plant Operating License--the Proposed Federal Action
    • 1.3 Purpose and Need for the Action
    • 1.4 Alternatives to the Proposed Action
    • 1.5 Analytical Approach Used in the GEIS
    • 1.6 Scope of the GEIS
    • 1.7 Implementation of the Rule
      • 1.7.1 General Requirements
      • 1.7.2 Applicant's Environmental Report
      • 1.7.3 The NRC's Supplemental Environmental Impact Statement
      • 1.7.4 Public Scoping and Public Comments on the SEIS
      • 1.7.5 Commission's Analysis and Preliminary Recommendation
      • 1.7.6 Final Supplemental Environmental Impact Statement
    • 1.8 References
  • 2. Description of Nuclear Power Plants and Sites, Plant Interaction with the Environment, and Environmental Impact Initiators Associated with License Renewal
    • 2.1 Introduction
    • 2.2 Plant and Site Description and Plant Operation
      • 2.2.1 External Appearance and Setting
      • 2.2.2 Reactor Systems
      • 2.2.3 Cooling and Auxiliary Water Systems
      • 2.2.4 Radioactive Waste Treatment Systems
      • 2.2.5 Nonradioactive Waste Systems
      • 2.2.6 Nuclear Power Plant Operation and Maintenance
      • 2.2.7 Power-Transmission Systems
    • 2.3 Plant Interaction with the Environment
      • 2.3.1 Land Use
      • 2.3.2 Water Use
      • 2.3.3 Water Quality
      • 2.3.4 Air Quality
      • 2.3.5 Aquatic Resources
      • 2.3.6 Terrestrial Resources
      • 2.3.7 Radiological Impacts
      • 2.3.8 Socioeconomic Factors
    • 2.4 License Renewal--The Proposed Federal Action
    • 2.5 Baseline Environmental Impact Initiators Associated with Continued Operation of Nuclear Power Plants
      • 2.5.1 Definition of Environmental Impact Initiators
      • 2.5.2 Baseline Environmental Impact Initiator Estimates
    • 2.6 Environmental Impact Initiators Associated with License Renewal and Continued Operation
      • 2.6.1 Scope and Objectives of Section 2.6
      • 2.6.2 Bases, Assumptions, and Approach
      • 2.6.3 Typical License Renewal Scenario
      • 2.6.4 Conservative License Renewal Scenario
      • 2.6.5 Impact Initiator Estimate Uncertainties
    • 2.7 Summary
    • 2.8 Endnotes
    • 2.9 References
  • 3. Environmental Impacts from Nuclear Power Plant Refurbishment
    • 3.1 Introduction
    • 3.2 On-Site Land Use
    • 3.3 Air Quality
    • 3.4 Surface Water and Groundwater Quality
      • 3.4.1 Surface Water
      • 3.4.2 Groundwater
    • 3.5 Aquatic Ecology
    • 3.6 Terrestrial Ecology
    • 3.7 Socioeconomic Impacts
      • 3.7.1 Introduction
      • 3.7.2 Housing
      • 3.7.3 Taxes
      • 3.7.4 Public Services
      • 3.7.5 Off-Site Land Use
      • 3.7.6 Economic Structure
      • 3.7.7 Historic and Archaeological Resources
      • 3.7.8 Aesthetic Resources
    • 3.8 Radiological Impacts
      • 3.8.1 Public Exposures
      • 3.8.2 Occupational Dose
    • 3.9 Threatened and Endangered Species
    • 3.10 Summary of Impacts of Refurbishment
    • 3.11 Endnotes
    • 3.12 References
  • 4. Environmental Impacts of Operation
    • 4.1 Introduction
    • 4.2 Once-Through Cooling Systems
      • 4.2.1 Surface Water Quality, Hydrology, and Use
      • 4.2.2 Aquatic Ecology
    • 4.3 Cooling Towers
      • 4.3.1 Introduction
      • 4.3.2 Surface Water Quality and Use
      • 4.3.3 Aquatic Ecology
      • 4.3.4 Agricultural Crops and Ornamental Vegetation
      • 4.3.5 Terrestrial Ecology
      • 4.3.6 Human Health
      • 4.3.7 Noise Impacts
    • 4.4 Cooling Ponds
      • 4.4.1 Introduction
      • 4.4.2 Surface Water Use and Quality
      • 4.4.3 Aquatic Ecology
      • 4.4.4 Terrestrial Ecology
    • 4.5 Transmission Lines
      • 4.5.1 Introduction
      • 4.5.2 Air Quality
      • 4.5.3 Land Use
      • 4.5.4 Human Health
      • 4.5.5 Surface Water Quality and Aquatic Ecology
      • 4.5.6 Terrestrial Ecology
      • 4.5.7 Floodplains and Wetlands
      • 4.5.8 Aesthetic Resources
    • 4.6 Radiological Impacts of Normal Operation
      • 4.6.1 Public Exposure
      • 4.6.2 Public Radiation Doses
      • 4.6.3 Occupational Radiation Dose
    • 4.7 Socioeconomic Impacts
      • 4.7.1 Housing
      • 4.7.2 Taxes
      • 4.7.3 Public Services
      • 4.7.4 Off-Site Land Use
      • 4.7.5 Economic Structure
      • 4.7.6 Aesthetic Resources
      • 4.7.7 Historic and Archaeological Resources
    • 4.8 Groundwater Use and Quality
      • 4.8.1 Groundwater Use
      • 4.8.2 Groundwater Quality
      • 4.8.3 Groundwater Quality Impacts of Cooling Ponds
    • 4.9 Summary of Impacts of Operation
    • 4.10 Endnotes
    • 4.11 References
  • 5. Environmental Impacts of Postulated Accidents
    • 5.1 Introduction
    • 5.2 Plant Accidents
      • 5.2.1 General Characteristics of Accidents
      • 5.2.2 Accident Experience and Observed Impacts
      • 5.2.3 Mitigation of Accident Consequences
    • 5.3 Accident Risk and Impact Assessment for License Renewal Period
      • 5.3.1 Regulatory Interface Between License Renewal and Accident Impacts
      • 5.3.2 Design-Basis Accidents
      • 5.3.3 Probabilistic Assessment of Severe Accidents
      • 5.3.4 Uncertainties
    • 5.4 Severe Accident Mitigation Design Alternatives (SAMDAs)
      • 5.4.1 Commission Experience Regarding Severe Accident Mitigation
    • 5.5 Summary and Conclusions
      • 5.5.1 Impacts from Design-Basis Accidents
      • 5.5.2 Impacts from Severe Accidents
    • 5.6 Endnotes
  • 6. The Uranium Fuel Cycle and Solid Waste Management
    • 6.1 Introduction
    • 6.2 Impacts of the Uranium Fuel Cycle
      • 6.2.1 Background of Tables S-3 and S-4
      • 6.2.2 Uranium Fuel Cycle Environmental Impact
      • 6.2.3 Sensitivity to Recent Changes in the Fuel Cycle
      • 6.2.4 Conclusions
    • 6.3 Transportation
      • 6.3.1 Introduction
      • 6.3.2 Table S-4--Environmental Impact of Transportation of Fuel and Waste to and from One Light-Water-Cooled Nuclear Power Reactor
      • 6.3.3 Effects of License Renewal
      • 6.3.4 Conclusion
    • 6.4 Generation and Storage of Radioactive Waste During the Term of the Renewed License
      • 6.4.1 Introduction
      • 6.4.2 Low-level Waste
      • 6.4.3 LLW Baseline
      • 6.4.4 Effects of License Renewal on LLW
      • 6.4.5 Mixed Waste
      • 6.4.6 Spent Fuel
    • 6.5 Nonradiological Wastes
      • 6.5.1 Baseline
      • 6.5.2 Effects of License Renewal
      • 6.5.3 Conclusion
    • 6.6 Summary
    • 6.7 Endnotes
    • 6.8 References
  • 7. Decommissioning
    • 7.1 Introduction
    • 7.2 The Decommissioning Process
      • 7.2.1 Nuclear Power Plants
      • 7.2.2 Decommissioning Methods
      • 7.2.3 Decommissioning Experience
      • 7.2.4 Inventory and Disposition of Radioactive Materials
    • 7.3 Decommissioning Impacts and Changes Resulting from Life Extension
      • 7.3.1 Radiation Dose
      • 7.3.2 Waste Management Impacts
      • 7.3.3 Air Quality Impacts
      • 7.3.4 Water Quality Impacts
      • 7.3.5 Ecological Impacts
      • 7.3.6 Economic Impacts
      • 7.3.7 Socioeconomic Impacts
    • 7.4 Conclusions
    • 7.5 References
  • 8. Alternatives to License Renewal
    • 8.1 Introduction
    • 8.2 Environmental Impacts of the No-Action Alternative
    • 8.3 Environmental Impacts of Alternative Energy Sources
      • 8.3.1 Wind
      • 8.3.2 Photovoltaic Cells
      • 8.3.3 Solar Thermal Power
      • 8.3.4 Hydropower
      • 8.3.5 Geothermal
      • 8.3.6 Wood Waste
      • 8.3.7 Municipal Solid Waste
      • 8.3.8 Energy Crops
      • 8.3.9 Coal
      • 8.3.10 Natural Gas
      • 8.3.11 Oil
      • 8.3.12 Advanced Light-Water Reactor
      • 8.3.13 Delayed Retirement of Existing Non-Nuclear Plants
      • 8.3.14 Conservation
      • 8.3.15 Imported Electrical Power
    • 8.4 Termination of Nuclear Power Plant Operations And Decommissioning
      • 8.4.1 Land Use
      • 8.4.2 Air Quality
      • 8.4.3 Water Resources
      • 8.4.4 Ecology
      • 8.4.5 Radiological Impacts
      • 8.4.6 Waste Management
      • 8.4.7 Socioeconomics
      • 8.4.8 Aesthetics Resources
    • 8.5 References
  • 9. Conclusions
  • 10. List of Preparers

Abstract

The Nuclear Regulatory Commission (NRC) anticipates that it will receive applications for renewal of the operating licenses of a significant portion of existing nuclear power plants. This Generic Environmental Impact Statement (GEIS) examines the possible environmental impacts that could occur as a result of renewing licenses of individual nuclear power plants under 10 CFR Part 54. The GEIS, to the extent possible, establishes the bounds and significance of these potential impacts. The analyses in the GEIS encompass all operating light-water power reactors. For each type of environmental impact the GEIS attempts to establish generic findings covering as many plants as possible. While plant and site-specific information is used in developing the generic findings, the NRC does not intend for the GEIS to be a compilation of individual plant environmental impact statements.

This GEIS has three principal objectives: (1) to provide an understanding of the types and severity of environmental impacts that may occur as a result of license renewal of nuclear power plants under 10 CFR Part 54, (2) to identify and assess those impacts that are expected to be generic to license renewal, and (3) to support a rulemaking (10 CFR Part 51) to define the number and scope of issues that need to be addressed by the applicants in plant-by-plant license renewal proceedings. To accomplish these objectives, the GEIS makes maximum use of environmental and safety documentation from original licensing proceedings and information from state and federal regulatory agencies, the nuclear utility industry, the open literature, and professional contacts.

Figures

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Figure 2.1 Pressurized-water-reactor power generation system

Figure 2.2 Boiling-water-reactor generating system

Figure 2.3 License renewal schedule and outage periods considered for environmental impact initiator definition

Figure 3.1 The seven case study nuclear plants

Figure 4.1 Examples of typical transmission line towers

Figure 5.1 Potential exposure pathways to individuals

Figure 5.2 Log plot of early fatalities (average deaths per reactor-year) for final environmental statement boiling-water reactor plants, fitted regression line (solid curve), and 95 percent normal-theory upper prediction confidence bounds (dotted curve)

Figure 5.3 Log plot of early fatalities (average deaths per reactor-year) for final environmental statement pressurized-water reactor plants, fitted regression line (solid curve), and 95 percent normal-theory upper prediction confidence bounds (dotted curve)

Figure 5.4 Log plot of normalized latent fatalities (average deaths per 1000 MW reactor-year) for final environmental statement boiling-water reactor plants, fitted regression line (solid curve), and 95 percent distribution-free upper prediction confidence bounds (dotted curve)

Figure 5.5 Log plot of normalized latent fatalities (average deaths per 1000 MW reactor-year) for final environmental statement pressurized-water reactor plants, fitted regression line (solid curve), and 95 percent distribution-free upper prediction confidence bounds (dotted curve)

Figure 5.6 Log plot of normalized total dose (person-rem per 1000 MW reactor-year) for final environmental statement boiling-water reactor plants, fitted regression line (solid curve), and 95 percent distribution-free upper prediction confidence bounds (dotted curve)

Figure 5.7 Log plot of normalized total dose (person-rem per 1000 MW reactor-year) for final environmental statement pressurized-water reactor plants, fitted regression line (solid curve), and 95 percent distribution-free upper prediction confidence bounds (dotted curve)

Figure 5.8 Water body surface areas and volumes within 80 km (50 miles) of representative nuclear power plant sites (potentially affected water bodies)

Figure 5.9 Water body surface areas and volumes within 80 km (50 miles) of the reactor site and within six of the 22.50 compass sectors that exhibit the greatest percentage of time for which the wind blows toward that compass direction (likely affected water bodies)

Figure 5.10 Water body flow rate at representative nuclear power plant sites

Figure 5.11 Contaminant residence time (flushing rate) and surface area-volume ratios for water bodies within an 80-km (50-mile) radius of selected nuclear power plants

Figure 6. 1 Low-level radioactive waste compact status

Figure 7.1 Typical pressurized-water reactor generating station layout

Figure 7.2 Site layout on a typical boiling-water reactor power plant

Figure 7.3 Buildup of activation products in pressurized-water reactor internal components as a function of effective full-power years

Figure 7.4 Time dependence of radioactivity and dose rate in a boiling-water reactor core shroud after 40 years of operation

Figure 8.1 U.S. wind energy resources

Figure 8.2 Solar resource availability: annual average daily direct normal solar radiation

Figure 8.3 U.S. conventional hydroelectric generating capacity, developed and undeveloped

Figure 8.4 U.S. known and potential geothermal energy resources

Acronyms and Abbreviations

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Executive Summary

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This Generic Environmental Impact Statement (GEIS) for license renewal of nuclear power plants was undertaken to

(1) assess the environmental impacts that could be associated with nuclear power plant license renewal and an additional 20 years of operation of individual plants and

(2) provide the technical basis for an amendment to the Nuclear Regulatory Commission's (NRC's) regulations, 10 CFR Part 51, "Environmental Protection Regulations for Domestic Licensing and Related Regulatory Functions," with regard to the renewal of nuclear power plant operating licenses. The rule amendment and this document were initiated to enhance the efficiency of the license renewal process by documenting in this GEIS and codifying in the Commission's regulations the environmental impacts that are well understood.

Under NRC's environmental protection regulations in 10 CFR Part 51, renewal of a nuclear power plant operating license is identified as a major federal action significantly affecting the quality of the human environment, and thus an environmental impact statement (EIS) is required for a plant license renewal review. The EIS requirements for a plant-specific license renewal review are specified in 10 CFR Part 51. Operating licenses may be renewed for up to 20 years beyond the 40-year term of the initial license. License renewal applicants perform evaluations and assessments of their facility to provide sufficient information for the NRC to determine whether continued operation of the facility during the renewal term will endanger public health and safety or the environment. The assessments also help to determine what activities and modifications are necessary at the time of license renewal and throughout the renewal term to ensure continued safe operation of the plant. Most utilities are expected to begin preparation for license renewal about 10 to 20 years before expiration of their original operating licenses. For the analysis in this GEIS, the staff anticipates that plant refurbishment undertaken specifically for license renewal would probably be completed during normal plant outage cycles, beginning 8 years before the original license expires, and during one longer outage, if a major refurbishment item is involved.

The Commission will act on an application for license renewal submitted by a licensee of an operating nuclear power plant. Although a licensee must have a renewed license to operate a plant beyond the term of the existing operating license, the possession of that license is just one of a number of conditions that must be met for the licensee to continue plant operation during the term of the renewed license. If the Commission grants a license renewal for a plant, state regulatory agencies and the owners of the plant would ultimately decide whether the plant will continue to operate based on factors such as need for power or other matters within the state's jurisdiction or the purview of the owners. Economic considerations will play a primary role in the decision made by state regulatory agencies and the owners of the plant. Thus, for license renewal reviews, the Commission has adopted the following definition of purpose and need:

The purpose and need for the proposed action (renewal of an operating license) is to provide an option that allows for power generation capability beyond the term of a current nuclear power plant operating license to meet future system generating needs, as such needs may be determined by State, utility, and, where authorized, Federal (other than NRC) decisionmakers.

In Chapter 8, the Commission considers the environmental consequences of the no-action alternative (i.e., denying a license renewal application) and the environmental consequences of the various alternatives for replacing lost generating capacity that would be available to a utility and other responsible energy planners. No conclusions are made in this document about the relative environmental consequences of license renewal or the construction and operation of alternative facilities for generating electric energy. The information in the GEIS is available for use by the NRC and the licensee in performing the site-specific analysis of alternatives. This information will be updated periodically, as appropriate.

The GEIS summarizes the findings of a systematic inquiry into the potential environmental consequences of renewing the licenses of and operating individual nuclear power plants for an additional 20 years. The inquiry identifies the attributes of the nuclear power plants, such as major features and plant systems, and the ways the plants can affect the environment. The inquiry also identifies the possible refurbishment activities and modifications to maintenance and operating procedures that might be undertaken given the requirements of the safety review as provided for in the Commission's regulations in 10 CFR Part 54, or given a utility's motivation to increase economic efficiency. Two scenarios were developed to identify possible initiators of environmental impacts from the possible set of refurbishment activities and continuation of plant operation during the renewal term. One scenario was developed as a typical but somewhat conservative scenario for license renewal, intended to be representative of the type of program that many licensees seeking license renewal might implement. The other scenario is highly conservative, encompassing considerably more activities, and is intended to characterize a reasonable upper bound of impact initiators that might result from license renewal.

The general analytical approach to each environmental issue is to (1) describe the activity that affects the environment, (2) identify the population or resource that is affected, (3) assess the nature and magnitude of the impact on the affected population or resource, (4) characterize the significance of the effect for both beneficial and adverse effects, (5) determine whether the results of the analysis apply to all plants, and (6) consider whether additional mitigation measures would be warranted for impacts that would have the same significance level for all plants.

A standard of significance was established for assessing environmental issues; and, because significance and severity of an impact can vary with the setting of a proposed action, both "context" and "intensity" as defined in the Council on Environmental Quality regulations (40 CFR 1508.27) were considered. With these standards as a basis, each impact was assigned to one of three significance levels:

Small: For the issue, environmental effects are not detectable or are so minor that they will neither destabilize nor noticeably alter any important attribute of the resource. For the purposes of assessing radiological impacts, the Commission has concluded that those impacts that do not exceed permissible levels in the Commission's regulations are considered small.

Moderate: For the issue, environmental effects are sufficient to alter noticeably but not to destabilize important attributes of the resource.

Large: For the issue, environmental effects are clearly noticeable and are sufficient to destabilize important attributes of the resource.

The discussion of each environmental issue in the GEIS includes an explanation of how the significance category was determined. For issues in which probability of occurrence is a key consideration (i.e., accident consequences), the probability of occurrence is factored into the determination of significance. In determining the significance levels, it is assumed that ongoing mitigation measures would continue and that mitigation measures employed during plant construction would be employed during refurbishment, as appropriate. The potential benefits of additional mitigation measures are not considered in determining significance levels.

In addition to determining the significance of environmental impacts associated with an issue for that issue, a determination was made whether the analysis in the GEIS could be applied to all plants and whether additional mitigation measures would be warranted. The categories to which an issue may be assigned follow.

This final GEIS assesses 92 environmental issues. Sixty-eight of these issues are found to be Category 1 and are identified in 10 CFR Part 51 as not requiring additional plant-specific analysis. Guidance on the analyses required for each of the other 24 issues is provided in 10 CFR Part 51. A summary of the findings for the 92 environmental issues is provided in Table 9.1 of this GEIS and summarized in narrative below.

Impacts of Refurbishment

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• On-site land use impacts are expected to be of small significance at all sites. Temporary disturbance of land may be mitigated by restoration to its original condition after refurbishment. This is a Category 1 issue.
• Nuclear power plant atmospheric emissions would either remain constant during refurbishment or decrease if the plant were partially or totally shut down. Small quantities of fugitive dust and gaseous exhaust emissions from motorized equipment operation during construction and refurbishment would temporarily increase ambient concentrations of particulate matter and gaseous pollutants in the vicinity of the activity but would not be expected to measurably affect ambient concentrations of regulated pollutants off-site. Additional exhaust emissions from the vehicles of up to 2300 personnel could be cause for some concern in geographical areas of poor or marginal air quality, but a general conclusion about the significance of the potential impact cannot be drawn without considering the compliance status of each site and the numbers of workers to be employed during the outage. This is a Category 2 issue.
• Proven erosion control measures such as best management practices are expected to be implemented at all plants and to minimize impacts to local water quality from runoff in disturbed areas. Consequently, impacts of refurbishment on surface water quality are expected to be of small significance at all plants. Because the effects of refurbishment are considered to be of small significance and potential mitigation measures are likely to be costly, the staff does not consider implementation of mitigation measures beyond best management practices to be warranted. This is a Category 1 issue.
• Additional water requirements during construction and refurbishment would be a small fraction of cooling water requirements of the operating power plant. If the plant were partially or totally shut down, cooling water use would decline. Water use during refurbishment is expected to have impacts of small significance on the local water supply. The only potential mitigation for any increase in water consumption would be to acquire the additional water from some other source. However, because this approach would provide very little, if any, environmental benefit and would be costly, the staff does not consider implementation of additional mitigation to be warranted. This is a Category 1 issue.
• Deep excavations and site dewatering would not be required during refurbishment. Consequently, the impacts of refurbishment on groundwater would be of small significance at all sites. No additional mitigation measures would be warranted because there would be no adverse impacts to mitigate. This is a Category 1 issue.
• Effluent discharges from the cooling system of a nuclear power plant would either remain constant during refurbishment or decrease if the plant were partially or totally shut down. Effects of changes in water withdrawals and discharges during refurbishment would be of small significance. No additional mitigation measures beyond those implemented during the current license term would be warranted because there would be no adverse impacts to mitigate. This is a Category 1 issue.
• The small on-site change in land use associated with refurbishment and construction could disturb or eliminate a small area of terrestrial habitat [up to 4 ha (10 acres)]. The significance of the loss of habitat depends on the importance of the plant or animal species that are displaced and on the availability of nearby replacement habitat. Impacts would be potentially significant only if they involved wetlands, staging or resting areas for large numbers of waterfowl, rookeries, restricted wintering areas for wildlife, communal roost sites, strutting or breeding grounds for gallinaceous birds, or rare plant community types. Because ecological impacts cannot be determined without considering site- and project-specific details, the potential significance of those impacts cannot be determined generically. This is a Category 2 issue.
• Because of refurbishment-related population increases, impacts on housing could be of moderate or large significance at sites located in rural and remote areas, at sites located in areas that have experienced extremely slow population growth (and thus slow or no growth in housing), or where growth control measures that limit housing development are in existence or have recently been lifted. This is a Category 2 issue.
• Tax impacts, which involve small to moderate increases in the direct and indirect tax revenues paid to local jurisdictions, are considered beneficial in all cases.
• In the area of public services, in-migrating workers could induce impacts of small to large significance to education, with the larger impacts expected to occur in sparsely populated areas. Impacts of small to moderate significance may occur to public utilities at some sites. Transportation impacts could be of large significance at some sites. These socioeconomic issues are Category 2.
• The impacts of refurbishment on other public services (public safety, social services, and tourism and recreation) are expected to be of small significance at all sites. No additional mitigation measures beyond those implemented during the current license term would be warranted because mitigation would be costly and the benefits would be small. These are Category 1 issues.
• In-migrating workers could induce impacts of small to moderate significance to off-site land use. The larger impacts are expected to occur in sparsely populated areas. This is a Category 2 issue.
• Based on the findings at the case study sites, refurbishment-related economic effects would range from small benefits to moderate benefits at all nuclear power plant sites. No adverse effects to economic structure would result from refurbishment-related employment.
• Site-specific identification of historic and archaeological resources and determination of impacts to them must occur during the consultation process with the State Historic Preservation Office (SHPO) as mandated by the National Historic Preservation Act. Impacts to historic resources could be large if the SHPO determines that significant historic resources would be disturbed or their historic character would be altered by plant refurbishment activities. The significance of potential impacts to historic and archaeological resources cannot be determined generically. This is a Category 2 issue.
• The impact on aesthetic resources is found to be of small significance at all sites. Because there will be no readily noticeable visual intrusion, consideration of mitigation is not warranted. This is a Category 1 issue.
• Radiation impacts to members of the public are considered to be of small significance because public exposures are within regulatory limits. Also, the estimated cancer risk to the average member of the public is much less than 1 x 10^-6. Because current mitigation practices have resulted in declining public radiation doses for nearly two decades, additional mitigation is not warranted. The impact on human health is a Category 1 issue.
• Occupational radiation exposure during refurbishment meets the ard of small significance. Because the as-low-as-reasonably-achievable (ALARA) program continues to reduce occupational doses, no additional mitigation program is warranted. This is a Category 1 issue.
• The significance of potential impacts to threatened and endangered species cannot be determined generically because compliance with the Endangered Species Act cannot be assessed without site-specific consideration of potential effects on threatened and endangered species. This is a Category 2 issue.

Impacts of Operation

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• It is not possible to reach a conclusion about the significance of potential impacts to threatened and endangered species at this time because (1) the significance of impacts on such species cannot be assessed without site- and project-specific information that will not be available until the time of license renewal and (2) additional species that are threatened with extinction and that may be adversely affected by plant operations may be identified between the present and the time of license renewal. This is a Category 2 issue.
• The staff examined nine aspects of water quality that might be affected by power plant operations: current patterns at intake and discharge structures, salinity gradients, temperature effects on sediment transport, altered thermal stratification of lakes, scouring from discharged cooling water, eutrophication, discharge of biocides, discharge of other chemical contaminants (e.g., metals), and discharge of sanitary wastes. Open-cycle cooling systems are more likely than other cooling systems to have such effects because they withdraw and discharge very large volumes of water; however, the impacts for each of these effects were found to be of small significance for all plants, regardless of cooling system type. For each type of impact, the staff considered potential mitigation measures but found that none were warranted because they would be costly and would have very small environmental benefits. These are Category 1 issues.
• The staff found no potential for water use conflicts or riparian plant and animal community impacts of moderate or large significance for plants with open-cycle cooling systems because they are used on large water bodies. Because the potential mitigation measures are costly and because the potential benefits are small, the staff does not consider mitigation to be warranted. These are Category 1 issues.
• The staff found that water use conflicts and the effects of consumptive water use on in-stream aquatic and riparian terrestrial communities could be of moderate significance at some plants that employ cooling-tower or cooling-pond systems because they are often located near smaller water bodies. For plants with these cooling systems, these are Category 2 issues.
• The staff examined 12 potential effects that nuclear power plant cooling systems may have on aquatic ecology: (1) impingement of fish; (2) entrainment of fish (early life stages); (3) entrainment of phytoplankton and zooplankton; (4) thermal discharge effects; (5) cold shock; (6) thermal plume barriers to migrating fish; (7) premature emergence of aquatic insects; (8) stimulation of nuisance organisms; (9) losses from predation, parasitism, and disease among organisms exposed to sublethal stresses; (10) gas supersaturation; (11) low dissolved oxygen in the discharge; and (12) accumulation of contaminants in sediments or biota. Except for three potential impacts (entrainment of fish and shellfish, impingement of fish and shellfish, and thermal discharge effects), each of these was found to be of small significance at all plants. Because mitigation would be costly and provide little environmental benefit, no additional mitigation measures beyond those implemented during the current license term are warranted. These are Category 1 issues. The other three impacts would be of small significance at all plants employing cooling-tower cooling systems. Because mitigation would be costly and provide little environmental benefit, no additional mitigation measures beyond those implemented during the current license term are warranted. For those plants, these are Category 1 issues. However, the impacts may be of greater significance at some plants employing open-cycle or cooling-pond systems; and these are Category 2 issues for those plants.
• The staff found that groundwater use of less than 0.0063 m³/s (100 gal/min) is of small significance because the cone of depression will not extend beyond the site boundary. Conflicts might result from several types of groundwater use by nuclear power plants. If groundwater conflicts arose, they could be resolvable by deepening the affected wells, but no such mitigation is warranted because sites producing less than 0.0063 m³/s (100 gal/min) would not have a cone of depression that extends beyond the site boundary. This is a Category 1 issue. Plants that extract more than 0.0063 m³/s (100 gal/min), including plants using Ranney wells, may have groundwater use conflicts of moderate or large significance. Groundwater use is a Category 2 issue for such plants.
• Cooling system makeup water consumption may cause groundwater use conflicts. During times of low flow, surface water withdrawals for cooling tower makeup from small rivers can reduce groundwater recharge. Because the significance of such impacts cannot be determined generically, this is a Category 2 issue.
• Groundwater withdrawals could cause adverse effects on groundwater quality by inducing intrusion of lower-quality groundwater into the aquifer. The staff found that the significance of these potential impacts is of small significance in all cases. Because all plants except Grand Gulf use relatively small quantities of groundwaters and surface water intrusion at Grand Gulf would not preclude current water uses, the staff found that mitigation was not warranted. This is a Category 1 issue.
• Cooling ponds leak an undetermined quantity of water through the pond bottom. Because the water in cooling ponds is elevated in salts and metals, such leakage may contaminate groundwater. The staff found that groundwater quality impacts of ponds that are located in salt marshes would be of small significance in all cases because salt marshes already have poor water quality. This is a Category 1 issue. Cooling ponds that are not located in salt marshes may have groundwater quality impacts of small, moderate, or large significance. This is a Category 2 issue.
• Small amounts of ozone and substantially smaller amounts of oxides of nitrogen are produced by transmission lines; however, ozone concentrations generated by transmission lines are too low to cause any significant effects. The minute amounts of oxides of nitrogen produced are also insignificant. Thus, air quality impacts associated with the operational transmission lines during the renewal term are expected to be of small significance at all sites. Potential mitigation measures would be very costly and are not warranted. This is a Category 1 issue.
• The potential impact of cooling tower drift on crops and ornamental vegetation arising from operations during the license renewal term is expected to be of small significance for all nuclear plants. No mitigation measures beyond those implemented during the current license term are warranted because there have been no measurable effects on crops or ornamental vegetation from cooling tower drift. This is a Category 1 issue.
• The impact of cooling towers on natural plant communities should continue not to result in measurable degradation as a result of license renewal and will therefore be of small significance. Because the impacts of cooling tower drift on native plants are expected to be small and because potential mitigation measures would be costly, no mitigation measures beyond those during the current term license would be warranted. This is a Category 1 issue.
• Bird mortality from collision with power lines associated with nuclear plants is of small significance for all plants because bird mortality is expected to remain a small fraction of total collision mortality associated with all types of man-made objects. Because the numbers of birds killed from collision with cooling towers are not large enough to affect local population stability or species function within the ecosystem, consideration of further mitigation is not warranted. Both bird collision with power lines and bird collision with cooling towers are Category 1 issues.
• Because no threat to the stability of local wildlife populations or vegetation communities is found for any cooling pond, the impacts are found to be of small significance. Potential mitigation measures would include excluding wildlife (e.g., birds) from contaminated ponds, converting to a dry cooling system, or reducing plant output during fogging or icing conditions. The impacts are found to be so minor that consideration of additional mitigation measures is not warranted. These effects of cooling ponds are so minor and so localized that cumulative impacts are not a concern. This is a Category 1 issue.
• Maintaining power-line right-of-ways (ROWs) causes fluctuations in wildlife populations, but the long-term effects are of small significance. The staff found that bird collisions with transmission lines are of small significance. Also, transmission line maintenance and repair would have impacts of only small significance on floodplains and wetlands. In each case, the staff found that potential mitigation measures beyond those implemented during the current license term would be costly and provide little environmental benefit, and thus are not warranted. These are Category 1 issues.
• Wildlife, livestock, and plants residing in power-line electromagnetic fields (EMF) apparently grow, survive, and reproduce as well as expected in the absence of EMF. The potential impact of EMF on terrestrial resources during the license renewal term is considered to be of small significance for all plants. Because the impact is of small significance and because mitigation measures could create additional environmental impacts and would be costly, no mitigation measures beyond those implemented during the current term license would be warranted. This is a Category 1 issue.
• Land use restrictions are necessary within transmission-line ROWs. The staff found these impacts to be of small significance at all sites. Mitigation beyond that imposed when ROWs were established might include relocating the transmission line. The staff concluded that such mitigation would not be warranted because it would be very costly and provide little environmental benefit. This is a Category 1 issue.
• During the license renewal term, the radiation dose commitment to the total worker population is projected to increase less than 5 percent at nuclear power plants under the typical scenario and less than 8 percent at any plant under the conservative scenario. The present operating experience results in about 30,000 person-rem/year for all licensed plants combined. After the period of refurbishment, routine operating conditions are expected to result in 32,000 person-rem/year for all plants combined. The risk associated with occupational radiation exposures after license renewal is expected to be of small significance at all plants. No mitigation measures beyond those implemented during the current license term are warranted because the existing ALARA process continues to be effective in reducing radiation doses. This is a Category 1 issue.
• Among the 150 million people who live within 50 miles of a U.S. nuclear power plant, about 30 million will die of spontaneous cancer unrelated to radiation exposure from nuclear power plants. This number is compared with approximately 5 calculated fatalities associated with potential nuclear-power-plant-induced cancer. The estimated annual cancer risk to the average individual is less than 1 x 10^-6. Public exposure to radiation during the license renewal term is of small significance at all sites, and no mitigation measures beyond those implemented during the current license term are warranted because current mitigation practices have resulted in declining public radiation doses and are expected to continue to do so. This is a Category 1 issue.
• The significance of potential for electrical shock from charges induced by transmission lines that may occur during the license renewal term cannot be evaluated generically because no National Electric Safety Code (NESC) review was performed for some of the earlier licensed plants. For those that underwent an NESC review, a change in the transmission line voltage may have been made since issuance of the initial operating license, or changes in land use since issuance of the original license could have occurred. This is a Category 2 issue.
• There is no consensus among scientists on whether 60-Hz EMF have a measurable human health impact. Because of inconclusive scientific evidence, the chronic effects of EMF would be not be categorized as either a Category 1 or 2 issue. If NRC finds that a consensus has been reached that there are adverse health effects, all license renewal applicants will have to address EMF effects in the license renewal process.
• Occupational health questions related to thermophilic organisms like Legionella are currently resolved using proven industrial hygiene principles to minimize worker exposures to these organisms in mists of cooling towers. Adverse occupational health effects associated with microorganisms are expected to be of small significance at all sites. Aside from continued application of accepted industrial hygiene procedures, no additional mitigation measures beyond those implemented during the current license term are warranted. This is a Category 1 issue.
• Thermophilic organisms may or may not be influenced by operation of nuclear power plants. The issue is largely unstudied. However, NRC recognizes a potential health problem stemming from heated effluents. Public health questions require additional consideration for the 25 plants using cooling ponds, lakes, canals, or small rivers because the operation of these plants may significantly enhance the presence of thermophilic organisms. The data for these sites are not now at hand, and it is impossible with current knowledge to predict the level of thermophilic organism enhancement at any given site. Thus, the impacts are not known and are site specific. Therefore, the magnitude of the potential public health impacts associated with thermal enhancement of N. fowleri cannot be determined generically. This is a Category 2 issue.
• The principal noise sources at power plants (cooling towers and transformers) do not change appreciably during the aging process. Because noise impacts have been found to be small and generally not noticed by the public, noise impacts are expected to be of small significance at all sites. Because noise reduction methods would be costly, and given that there have been few complaints, no additional mitigation measures are warranted for license renewal. This is a Category 1 issue.
• The staff examined socioeconomic effects of nuclear power plant operations during a license renewal period. Five of these would be of small significance at all sites: education, public safety, social services, recreation and tourism, and aesthetics. Because mitigation measures beyond those implemented during the current license term are costly and would offer little benefit, no additional mitigation measures are warranted. These are Category 1 issues. Four of the socioeconomic effects were found to have moderate or large significance at some sites: housing, transportation, public utilities (especially water supply), and off-site land use. These are Category 2 issues. In addition, the statute (National Historic Preservation Act) requires consultation; thus historic and archaeological resources are Category 2 issues.

Accidents

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• The environmental impacts of postulated accidents were evaluated for the license renewal period in GEIS Chapter 5. All plants have had a previous evaluation of the environmental impacts of design-basis accidents. In addition, the licensee will be required to maintain acceptable design and performance criteria throughout the renewal period. Therefore, the calculated releases from design-basis accidents would not be expected to change. Since the consequences of these events are evaluated for the hypothetical maximally exposed individual at the time of licensing, changes in the plant environment will not affect these evaluations. Therefore, the staff concludes that the environmental impacts of design-basis accidents are of small significance for all plants. Because the environmental impacts of design basis accidents are of small significance and because additional measures to reduce such impacts would be costly, the staff concludes that no mitigation measures beyond those implemented during the current term license would be warranted. This is a Category 1 issue.
• The staff concluded that the generic analysis of severe accidents applies to all plants and that the probability-weighted consequences of atmospheric releases, fallout onto open bodies of water, releases to groundwater, and societal and economic impacts of severe accidents are of small significance for all plants. However, not all plants have performed a site-specific analysis of measures that could mitigate severe accidents. Consequently, severe accidents are a Category 2 issue for plants that have not performed a site-specific consideration of severe accident mitigation and submitted that analysis for Commission review.

Uranium Fuel Cycle and Management of Waste

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• The radiological and nonradiological environmental impacts of the uranium fuel cycle have been reviewed. The review included a discussion of the values presented in Table S-3, an assessment of the release and impact of ²²²Rn and of ⁹⁹Tc, and a review of the regulatory standards and experience of fuel cycle facilities. For the purpose of assessing the radiological impacts of license renewal, the Commission uses the standard that the impacts are of small significance if doses and releases do not exceed permissible levels in the Commission's regulation. Given the available information regarding the compliance of fuel-cycle facilities with applicable regulatory requirements, the Commission has concluded the actual impacts of the fuel cycle are at or below existing regulatory limits. Accordingly, the Commission concludes that individual radiological impacts of the fuel cycle (other than the disposal of spent fuel and high-level waste) are small. With respect to the nonradiological impact of the uranium fuel cycle, data concerning land requirements, water requirements, the use of fossil fuel, gaseous effluent, liquid effluent, and tailings solutions and solids, all listed in Table S-3, have been reviewed to determine the significance of the environmental impacts of a power reactor operating an additional 20 years. The nonradiological environmental impacts attributable to the relicensing of an individual power reactor are found to be of small significance. The individual radiological and the nonradiological effects of the uranium fuel cycle are Category 1 issues.
  
  The radiological impacts of the uranium fuel cycle on human populations over time (collective effects) have been considered within the framework of Table S-3. The 100-year environmental dose commitment to the U.S. population from the fuel cycle, high-level-waste and spent-fuel disposal excepted, is calculated to be about 14,800 man-rem, or 12 cancer fatalities, for each additional 20-year power-reactor operating term. Much of this, especially the contribution of radon releases from mines and tailing piles, consists of tiny doses summed over large populations. This same dose calculation can theoretically be extended to include many tiny doses over additional thousands of years as well as doses outside the United States. The result of such a calculation would be thousands of cancer fatalities from the fuel cycle, but this result assumes that even tiny doses have some statistical adverse health effect that will not ever be mitigated (for example, no cancer cure in the next thousand years) and that these dose projections over thousands of years are meaningful. However, these assumptions are questionable. In particular, science cannot rule out the possibility that there will be no cancer fatalities from these tiny doses. For perspective, the doses are very small fractions of regulatory limits and even smaller fractions of natural background exposure to the same populations. No standards exist that can be used to reach a conclusion as to the significance of the magnitude of the collective radiological effects. Nevertheless, some judgment as to the regulatory NEPA implication of this issue should be made, and it makes no sense to repeat the same judgment in every case. The Commission concludes that these impacts are acceptable in that these impacts would not be sufficiently large to require the NEPA conclusion, for any plant, that the option of extended operation under 10 CFR Part 54 should be eliminated. Accordingly, while the Commission has not assigned a single level of significance for the collective effects of the fuel cycle, this issue is considered Category 1.
  
  There are no current regulatory limits for off-site releases of radionuclides from high-level-waste and spent-fuel disposal at the current candidate repository site at Yucca Mountain. If we assume that limits are developed along the lines of the 1995 National Academy of Sciences report and that, in accordance with the Commission's Waste Confidence Decision, a repository can and likely will be developed at some site that will comply with such limits, peak doses to virtually all individuals will be 100 mrem/year or less. However, while the Commission has reasonable confidence that these assumptions will prove correct, there is considerable uncertainty since the limits are yet to be developed, no repository application has been completed or reviewed, and uncertainty is inherent in the models used to evaluate possible pathways to the human environment. The National Academy report indicates that 100 mrem/year should be considered as a starting point for limits for individual doses but notes that some measure of consensus exists among national and international bodies that the limits should be a fraction of the 100 mrem/year. The lifetime individual risk from 100-mrem/year dose limit is about 3 x 10^-3. Doses to populations from disposal cannot now (or possibly ever) be estimated without very great uncertainty. Estimating cumulative doses to populations over thousands of years is more problematic. The likelihood and consequences of events that could seriously compromise the integrity of a deep geologic repository have been evaluated by the Department of Energy (DOE) and the NRC, and other federal agencies have expended considerable effort to develop models for the design and for the licensing of a high-level-waste repository, especially for the candidate repository at Yucca Mountain. More meaningful estimates of doses to population may be possible in the future as more is understood about the performance of the proposed Yucca Mountain repository. Such estimates would involve very great uncertainty, especially with respect to cumulative population doses over thousands of years. The standard proposed by the NAS is a limit on maximum individual dose. The relationship of potential new regulatory requirements, based on the NAS report, and cumulative population impacts has not been determined, although the report articulates the view that protection of individuals will adequately protect the population for a repository at Yucca Mountain. However, EPA's generic repository standards in 40 CFR Part 191 generally provide an indication of the order of magnitude of cumulative risk to population that could result from the licensing of a Yucca Mountain repository, assuming the ultimate standards will be within the range of standards now under consideration. The standards in 40 CFR Part 191 protect the population by imposing "containment requirements" that limit the cumulative amount of radioactive material released over 10,000 years. The cumulative release limits are based on EPA's population impact goal of 1,000 premature cancer deaths worldwide for a 100,000-metric tonne (MTHM) repository.
  
  Nevertheless, despite all the uncertainty surrounding the effects of the disposal of spent fuel and high-level waste, some judgment as to the regulatory NEPA implications of these matters should be made, and it makes no sense to repeat the same judgment in every case. Even taking the uncertainties into account, the Commission concludes that these impacts are acceptable in that these impacts would not be sufficiently large to require the NEPA conclusion, for any plant, that the option of extended operation under 10 CFR Part 54 should be eliminated. Accordingly, while the Commission has not assigned a single level of significance for the impacts of spent-fuel and high-level-waste disposal, this issue is considered Category 1.
• The radiological and nonradiological environmental impacts from the transportation of fuel and waste attributable to license renewal of a power reactor have been reviewed. Environmental impact data for transportation are provided in Table S-4. The estimated radiological effects are within the Commission's regulatory standards. Radiological impacts of transportation are therefore found to be of small significance when they are within the range of impact parameters identified in Table S-4. The nonradiological impacts are those from periodic shipments of fuel and waste by individual trucks or rail cars and thus would result in infrequent and localized minor contributions to traffic density. These nonradiological impacts are found to be small when they are within the range of impact parameters identified in Table S-4. Programs designed to reduce risk, which are already in place, provide for adequate mitigation. Table S-4 should continue to be the basis for case-by-case evaluations of transportation impacts of spent fuel until such time as detailed analysis of the environmental impacts of transportation to the Yucca Mountain repository becomes available. Transportation of fuel and waste is a Category 2 issue.
• The radiological and nonradiological environmental impacts from the storage and disposal of low-level radiological waste attributable to license renewal of a power reactor have been reviewed. The comprehensive regulatory controls that are in place and the low public doses being achieved at reactors ensure that the radiological impacts to the environment will remain small during the term of the renewed license. The maximum additional on-site land that may be required for low-level waste storage during the term of a renewed license and associated impacts will be small. Nonradiological environmental impacts on air and water will be negligible. The radiological and nonradiological environmental impacts of long-term disposal of low-level waste from any individual plants at licensed sites are small. The need for the consideration of mitigation alternatives within the context of renewal of a power reactor license has been considered, and the Commission concludes that its regulatory requirements already in place provide adequate mitigation incentives for on-site storage of low-level waste and that, for off-site disposal, mitigation would be a site-specific consideration in the licensing of each facility. In addition, the Commission concludes that there is reasonable assurance that sufficient low-level waste disposal capacity will be made available when needed for facilities to be decommissioned consistent with NRC decommissioning requirements. Low-level waste is a Category 1 issue.
• The radiological and nonradiological environmental impacts from the storage and disposal of mixed waste attributable to license renewal of a power reactor have been reviewed. The comprehensive regulatory controls and the facilities and procedures that are in place ensure proper handling and storage, as well as negligible doses and exposure to toxic materials for the public and the environment at all plants. License renewal will not increase the small, continuing risk to human health and the environment posed by mixed waste at all plants. The radiological and nonradiological environmental impacts of long-term disposal of mixed waste from any individual plant at licensed sites are small. The maximum additional on-site land that may be required for mixed waste is a small fraction of that needed for low-level waste storage during the term of a renewed license, and associated impacts will be small. Nonradiological environmental impacts on air and water will be negligible. The radiological and nonradiological environmental impacts of long-term disposal of mixed waste from any individual plants at licensed sites are small. The need for the consideration of mitigation alternatives within the context of renewal of a power reactor license has been considered, and the Commission concludes that its regulatory requirements already in place provide adequate mitigation incentives for on-site storage of mixed waste and that, for off-site disposal, mitigation would be a site-specific consideration in the licensing of each facility. In addition, the Commission concludes that there is reasonable assurance that sufficient mixed waste disposal capacity will be made available when needed for faculties to be decommissioned consistent with NRC decommissioning requirements. Mixed waste is a Category 1 issue.
• The Commission's waste confidence finding at 10 CFR 51.23 leaves only the on-site storage of spent fuel during the term of plant operation as a high-level waste storage and disposal issue at the time of license renewal. The Commission's regulatory requirements and the experience with on-site storage of spent fuel in fuel pools and dry storage have been reviewed. Within the context of a license renewal review and determination, the Commission finds that there is ample basis to conclude that continued storage of existing spent fuel and storage of spent fuel generated during the license renewal period can be accomplished safely and without significant environmental impacts. Radiological impacts will be well within regulatory limits; thus radiological impacts of on-site storage meet the standard for a conclusion of small impact. The nonradiological environmental impacts have been shown to be not significant; thus they are classified as small. The overall conclusion for on-site storage of spent fuel during the term of a renewed license is that the environmental impacts will be small for each plant. The need for the consideration of mitigation alternatives within the context of renewal of a power reactor license has been considered, and the Commission concludes that its regulatory requirements already in place provide adequate mitigation incentives for on-site storage of spent fuel. On-site storage of spent fuel during the term of a renewed operating license is a Category 1 issue.
• The environmental impacts from the storage and disposal of nonradiological waste attributable to the license renewal of a power reactor have been reviewed. Regulatory and operational trends suggest a gradual decrease in quantities generated annually and the impacts during the terms of renewed licenses. Facilities and procedures are in place to ensure continued proper handling and disposal at all plants. Consequently, the generation and management of solid nonradioactive waste during the term of a renewed license is anticipated to result in only small impacts to the environment. Because the facilities and procedures that are in place are expected to ensure continued proper handling and disposal at each plant, additional mitigative measures are not a consideration in the context of a license renewal review. Nonradiological waste is a Category 1 issue.

Decommissioning

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• Decommissioning after a 20-year license renewal would increase the occupational dose no more than 0.1 person-rem (compared with 7,000 to 14,000 person-rem for DECON decommissioning at 40 years) and the public dose by a negligible amount. License renewal would not increase to any appreciable extent the quantity or classification of LLW generated by decommissioning. Air quality, water quality, and ecological impacts of decommissioning would not change as a result of license renewal. There is considerable uncertainty about the cost of decommissioning; however, while license renewal would not be expected to change the ultimate cost of decommissioning, it would reduce the present value of the cost. The socioeconomic effects of decommissioning will depend on the magnitude of the decommissioning effort, the size of the community, and the other economic activities at the time, but the impacts will not be increased by decommissioning at the end of a 20-year license renewal instead of at the end of 40 years of operation. Incremental radiation doses, waste management, air quality, water quality, ecological, and socioeconomic impacts of decommissioning due to operations during a 20-year license renewal term would be of small significance. No mitigation measures beyond those provided by ALARA are warranted within the context of the license renewal process. The impacts of license renewal on radiation doses, waste management, air quality, water quality, ecological resources, and socioeconomics impacts from decommissioning are Category 1 issues.