Continued Safe Storage of Used Nuclear Fuel

San Onofre nuclear plant, like nuclear power plants throughout the United States, has a process for safely managing and storing used nuclear fuel and protecting workers, the public and the environment. San Onofre safely stores used uranium fuel on site using a combination of technologies: enclosed, steel-lined pools (spent fuel pools) and sealed stainless steel canisters that are housed in reinforced concrete structures (dry cask storage).

Now that San Onofre is permanently retired, Southern California Edison (SCE) is taking steps to transfer in the process of transferring all of the used nuclear fuel into dry cask storage. This proven technology involves sealing used fuel in airtight steel (or in steel and concrete) containers or casks that provide both structural strength and shielding. Dry cask storage systems are designed to withstand various natural phenomena such as floods, projectiles from a tornado, seismic events, temperature extremes and lightning.

In 2014, SCE established a Community Engagement Panel (CEP) to advise the company on decommissioning San Onofre, including issues such as interim storage of used nuclear fuel. The CEP has heard presentations from federal regulators, dry storage suppliers and energy policy experts on issues ranging from dry storage technology to national energy policy. Currently, about one-third of San Onofre’s used nuclear fuel is in dry storage and SCE plans to transfer all remaining fuel to dry storage by mid-2019.

The fuel will remain on site until the federal government puts in place a program to dispose of these materials. By law, the U.S. Department of Energy is responsible for developing a disposal facility for the long-term management of used uranium fuel from San Onofre and other U.S. nuclear power plants. However, the federal government does not have a viable program for the management of used nuclear fuel. After two years of study, the President’s Blue Ribbon Commission on America’s Future issued recommendations to create a safe, long-term solution for managing and disposing of used nuclear fuel.

The U.S Nuclear Regulatory Commission strictly regulates the management and storage of used nuclear fuel. In addition, the Nuclear Energy Institute, an industry trade association, has information about the industry practices regarding used fuel storage, as well as the NRC’s updated rule on continued storage of used nuclear fuel (previously known as waste confidence).


Consent-based Consolidated Interim Storage (CIS) of used nuclear fuel was recommended by the President's Blue Ribbon Commission on Nuclear Energy in 2012 as part of an integrated waste management plan. Public interest in CIS has grown in southern California following the retirement of San Onofre nuclear plant. Two proposed CIS sites in the southwest are the primary focus: Carlsbad, New Mexico, which already is home to a deep geologic depository called the Waste Isolation Pilot Plant, and Andrews, Texas, home to Waste Control Specialists. CIS is part of DOE's three-pronged strategy to manage used nuclear fuel: a pilot, interim storage facility with limited capacity that will be focused on fuel from the decommissioned sites (scheduled to open by 2021); a larger CIS facility (either co-located with the pilot facility and/or geologic repository); and a permanent geologic repository for disposal of used nuclear fuel and high-level radioactive waste (Yucca Mountain). Pending legislation to authorize CIS and manage used nuclear fuel includes the Interim Consolidated Storage Act of 2015 and similar legislation introduced in 2016. DOE hosted public meetings throughout the country in 2016, including Sacramento, CA, to get public comment to shape a fair and effective process for a CIS site.


In 1987, Congress amended the Nuclear Waste Policy Act of 1982 to establish Yucca Mountain as the nation's geologic repository for high-level nuclear waste. In 2008, the Department of Energy submitted a license application to the U.S. Nuclear Regulatory Commission (NRC) to begin construction of the facility on federally owned desert land about 100 miles northwest of Las Vegas. However, progress on the proposed storage facility has been stalled since then by opposition led by Nevada political figures and with the support of the Obama administration. In May 2016, the NRC released a final environmental impact statement (EIS) for the proposed project, finding the potential impacts on groundwater and surface groundwater discharges and determines all impacts would be "small."


The chairman of the San Onofre Community Engagement Panel (CEP), David Victor, has taken a strong leadership role advocating for off-site storage of San Onofre's used nuclear fuel. CEP member Jerry Kern, who serves as an Oceanside councilman, has spearheaded efforts by area local governments to pass resolutions urging the federal government to authorize off-site storage for the used nuclear fuel. In 2015-2016, his resolutions focused on legislation introduced by U.S. Rep. Mike Conaway, R-Texas, (H.R. 3643), the Interim Consolidated Storage Act of 2015, and co-sponsored by U.S. Rep. Darrell Issa, R-Vista. Sen. U.S. Sen. Dianne Feinstein, D-Calif., co-sponsored similar bipartisan legislation in the Senate. These measures would amend the existing Nuclear Waste Policy Act allowing the DOE to take title to the nuclear waste and contract with private companies to store the waste at a consolidated site. In addition, the California state senate in April 2016 approved a resolution authored by state Sen. Patricia Bates (R-Laguna Niguel) urging Congress to approve legislation (H.R. 4745) authorizing off-site storage of used nuclear fuel.

In 2017, Rep. Issa introduced HR 474, Interim Consolidated Storage Act of 2017 on January 12.  The bill is before the House Energy and Commerce Committee, and co-sponsors include California Representatives Ken Calvert (R-CA-42), Scott Peters (D-CA-52), Doris Matsui (D-CA-6), Ami Bera (D-CA-7), Duncan Hunter (R-CA-52) and Dana Rohrabacher (R-CA-48).  For more information on the bill’s current status click here.

U.S. Rep. John Shimkus (R-IL), chairman of the House Energy and Commerce Subcommittee on Environment, introduced HR 3053, the Nuclear Waste Policy Amendments Act, in April 2017. The legislation was approved by the House Energy and Commerce Committee on June 28 and awaits consideration by the full House this summer.


The NRC has determined that used nuclear fuel can be stored safely at a power plant or central storage facilities for at least 120 years. Nuclear power plants throughout the United States have been safely storing used nuclear fuel in steel-lined concrete pools, and in 1986 began expanding capacity by adopting dry storage technology. Thirty-four states have at least one dry cask storage facility; these are formally known as Independent Spent Fuel Storage Installations. Eleven states currently have shutdown reactors without an operating reactor, including three in California. San Onofre, one of those three sites, has safely stored used nuclear fuel for more than three decades. San Onofre has about 2,668 fuel assemblies in spent fuel pools for Units 2 and 3 and about 800 Unit 2 and 3 fuel assemblies in dry cask storage. There are about 400 Unit 1 used nuclear fuel assemblies in dry cask storage on site. In addition, there are 270 fuel assemblies for Unit 1 stored offsite at General Electric's used fuel storage facility in Morris, Ill. All of San Onofre's used fuel currently in spent fuel pools is scheduled to be transferred to dry storage by 2019.