An Environmental Impact Statement (EIS) is in the early planning stages by the U.S. Nuclear Regulatory Commission (NRC) to evaluate increasing the Waste Confidence Decision and Waste Confidence Rule from 120 years to 300 years. The existing Decision and Rule assume that SNF will be stored during the initial 40-year term of the nuclear power plant’s operating license, and during the additional 20-year term of the renewed license, and then for another 60 years after the plant has been shut down. NRC is now in the planning processes to increase the post-shutdown storage period to 240 years, which would allow SNF to be stored either at a nuclear reactor site or off-site for up to 300 years. The evaluation of this increased time frame for SNF storage will include the preparation and distribution of a draft EIS, the solicitation of public comments, and issuance of a final EIS that addresses comments received.
Long-Term Assumptions Underlying the EIS for 300-Year Waste Confidence
Use of nuclear power will continue to provide the US with approximately 20% of its energy needs while generating approximately 2,000 metric tons of SNF each year.
- The same type of nuclear fuel will continue to be used in commercial nuclear power plants in the US, and any future fuel types will not create significantly different storage and transportation impacts.
- Dry cask storage will be the primary mode of SNF storage although limited long-term storage in wet fuel pools will also occur.
- Present-day transportation infrastructure and modes (rail, truck, and barge) will be available in the future; however, aging effects on dry casks and re-packaging impacts on transportation will be evaluated.
- Long-term SNF storage will include a program to monitor, detect and mitigate the effects of aging, but significant mitigation actions may include refurbishment and repackaging.
- Regulatory program for SNF storage will continue including oversight and enforcement, and financial assurance for SNF will be maintained.
- Either 25% or 75% of the commercial SNF will be reprocessed prior to transport to a disposal facility.
- Reasonable accident scenarios for both SNF storage and transportation are assumed possible and causes could include human error, mechanical failure and natural events.
- The generic environmental impacts resulting from an act of terrorism against a dry cask storage facility or SNF transportation will be evaluated.
The EIS will consider 4 different “scenarios” that are intended to bound the potential environmental impacts associated with 300 years of SNF storage. Each scenario assumes that ultimately the SNF will be transported to at least one geologic repository for disposal. Generic impacts will be evaluated for a number of different generic sites (ranging from 5 to more than 20). Each generic site will reflect composite characteristics of actual and proposed operating and decommissioned nuclear power plant sites, on-site and off-site storage facilities, and other storage and handling facilities.
Four Long-Term Scenarios Considered for 300-Year Waste Confidence
SCENARIO 1: Extended onsite storage (some in pools) of SNF at nuclear power reactor sites and off-site (away-from-reactor) storage at ISFSIs.
SCENARIO 2: Interim on-site storage of SNF at nuclear power reactor sites and shipment of at least 50% of the SNF to one or more regional dry cask storage facilities (2 to 4 generic sites considered) that are operated privately or by the government.
SCENARIO 3: Interim on-site storage of SNF at nuclear power reactor sites and shipment of a significant amount of that SNF to one centralized storage facility or monitored retrievable storage facility operated by DOE or another federal entity.
SCENARIO 4: Interim on-site storage of SNF at nuclear power reactor sites and shipment of a significant amount of that SNF to one or more reprocessing facilities (one or more generic sites considered) that is co-located at an interim storage facility.