The U.S. Nuclear Regulatory Commission (NRC) is an independent authority regulating the possession and use of nuclear materials as well as the siting, construction, and operation of nuclear facilities. NRC regulates commercial nuclear fuel cycle materials and facilities, commercial sealed sources, including disused sealed sources. NRC also oversees certain state programs where NRC has relinquished limited regulatory authority to the individual states. The 50 U.S. States have the responsibility to provide for disposal of Class A, B, and C LLW, and may join together as compacts for this purpose.
The U.S. Department of Energy (DOE) is responsible for and performs most of the spent fuel and radioactive waste management activities for DOE-owned and generated waste and materials, mostly located on Government-owned sites. DOE is also responsible for disposition of high-level waste and spent fuel, and Greater-than-Class C low-level radioactive waste. DOE operates the Waste Isolation Pilot Plant, a geologic repository for defense TRU waste.
The U.S. Environmental Protection Agency (EPA) establishes generally applicable environmental standards to protect the environment from hazardous materials and certain radioactive materials. EPA establishes standards for remediating active and inactive uranium mill tailing sites, environmental standards for the uranium fuel cycle, and environmental radiation protection standards for management and disposal of spent fuel, HLW, and TRU waste. EPA promulgates standards for and certifies compliance at WIPP.
Owners and operators of nuclear power plants and other types of facilities generating radioactive waste manage radioactive waste generated by their facilities prior to disposal. There is a commercial market for radioactive waste management services in the U.S. and licensees may hire commercial firms or self perform work. U.S. Federal or state governments, however, will ultimately administer waste disposal sites. Government custody may occur at different stages of the waste management scheme depending on the type of radioactive waste and generating activity.
Commercial and government facilities exist for low-level radioactive waste (LLW) processing, including treatment, conditioning, and disposal. Generators prepare LLW for shipment to licensed disposal facilities. Class A, B and C LLW is disposed in near surface facilities, i.e., a land disposal facility in which radioactive waste is disposed of in or within the upper 30 meters of the earth’s surface. Greater-Than-Class C LLW is stored until an adequate method of disposal is established
Transuranic waste generally consists of protective clothing, tools, glassware, equipment, soils, and sludge contaminated with manmade radioisotopes beyond or “heavier” than uranium on the periodic table of the elements. These elements include plutonium, neptunium, americium, curium, and californium. TRU waste is produced during nuclear fuel research and development; and during nuclear weapons research, production, and cleanup. TRU waste from the government’s defense activities is disposed in a deep geologic repository, the Waste Isolation Pilot Plant.
High level waste (HLW) from commercial reprocessing activities was vitrified and is stored at the former reprocessing plant in West Valley, New York. Defense HLW is stored, managed and treated at three DOE sites.
Uranium recovery is the extraction or concentration of uranium from any ore processed primarily for its source material content. This results in waste from uranium solution extraction processes. These wastes usually have relatively low concentrations of radioactive materials with long half lives. Uranium recovery facilities shut down or scaled back operations in the early 1980s, when the price of uranium fell. Many of the previously operating facilities were reclaimed or are in the process of remediating (decommissioning) waste resulting from extracting uranium. The product from uranium recovery facilities is processed to enrich the fissile content. Tailings containing depleted uranium are a by-product of the enrichment process. Numerous tailings disposal facilities exist within the U.S.
Radioactive wastes are treated primarily to produce a structurally stable, final waste form and minimize the release of radioactive and hazardous components. The United States does not commonly make a distinction between the terms treatment and conditioning. U.S. terminology covering both conditioning and treatment is generally referred to as treatment or processing.
Commercial generators of LLW waste in the United States must treat these wastes to remove free liquids, and stabilize or destroy other hazardous components contained in the waste. Wastes are also often treated to reduce the final disposal volume through compaction and incineration. Private companies in the United States provide processing (e.g. packaging and treatment) and brokerage services to facilitate safe storage, transportation and,ultimately, disposal of LLW at one of three commercial disposal facilities. Some of these waste processor/brokers serve limited clientele. Others perform these services for a wider body of clients.
DOE has numerous facilities for management of waste at its sites. Many facilities exist to provide lag storage until waste is treated and disposed.
HLW is stored at four sites where it was generated from reprocessing of spent fuel:
- All HLW generated from reprocessing at the former commercial reprocessing plant at West Valley, New York, between 1966 and 1972 was vitrified and is awaiting disposal.
- HLW from reprocessing defense materials at the Savannah River Site consists of both insoluble solid chemicals and water soluble salts. The waste is stored in underground stainless steel tanks until treated. Waste is being transferred to the site’s Defense Waste Processing Facility (DWPF) for immobilization in borosilicate glass.
- Reprocessing defense materials at the Hanford Site began in 1944, and ended nearly 50 years later. The waste is stored in 177 underground tanks. DOE plans to process the tank waste after treatment (vitrification of HLW). Design and construction of the Waste Treatment Plant, which includes a pre-treatment facility, low-activity waste treatment facility, HLW facility, and analytical laboratory is progressing.
- HLW from more than 50 years of defense spent fuel reprocessing at Idaho National Laboratory has been stored in tanks and treated for disposal. Much of the waste was previously treated and is now stored as dry granular calcine in stainless steel bins. The remaining liquid HLW contains a high concentration of sodium, and will be treated by steam reforming.
Residual waste in the tanks at Hanford, Idaho and Savannah River has been managed as HLW. DOE may determine certain quantities of this residual waste from reprocessing are not HLW if certain conditions are met. DOE consults with NRC prior to making such determinations and depending on the location, follows the process set forth in section 3116 of the National Defense Authorization Act (NDAA) for Fiscal Year 2005 or the Waste Incidental to Reprocessing (WIR) provisions of DOE Manual 435.1-1, Radioactive Waste Management.
WIPP is a geologic repository to dispose, safely and permanently, TRU waste left from the research and production of nuclear weapons. WIPP began operations on March 26, 1999, after more than 20 years of scientific study, public input, and regulatory review.
There are currently three active, licensed commercial LLW disposal sites. A license application for a fourth facility has been issued:
- EnergySolutions/Chem-Nuclear, formerly GTS-Duratek (Barnwell, South Carolina) - As of July 2008, access is limited to LLW generators within three states composing the Atlantic Compact (South Carolina, Connecticut, and New Jersey). Barnwell disposes of Class A, B and C LLW.
- U.S. Ecology (on DOE’s Hanford Site near Richland, Washington) - restricted access to only the Northwest and Rocky Mountain Compacts. U.S. Ecology disposes of Class A, B and C LLW.
- EnergySolutions, formerly Envirocare of Utah (Clive, Utah) - accepts Class A LLW and mixed LLW for LLW generators not limited or bound by compact rules. See Section H.1 for additional information.
- A license application was issued in 2009 by the State of Texas for a new commercial LLW disposal site at Waste Control Specialists near Andrews, Texas. The proposed site includes a facility to dispose of LLW for the Texas compact and a facility to dispose of Federal mixed LLW and LLW.
Commercial LLW sites now closed are: Beatty, Nevada (closed 1993); Maxey Flats, Kentucky (closed 1977); Sheffield, Illinois (closed 1978), and West Valley, New York (closed 1975).
DOE operates disposal facilities for LLW at: Hanford, Washington; Idaho Site, Idaho; Los Alamos National Laboratory (LANL), New Mexico; Nevada Test Site, Nevada; and Savannah River Site, South Carolina. DOE also operates LLW disposal facilities for waste from cleanup projects (generally large volumes with low concentrations) at Hanford Site, Idaho Site, and Oak Ridge Reservation in Tennessee.
There are also closed disposal facilities managed by DOE. The Greater Confinement Disposal Facility (boreholes) was used to dispose of certain TRU and other defence waste at the Nevada Test Site until 1989. There are closed burial grounds for LLW used decades ago for disposal of wastes resulting from defence activities, e.g., at Hanford, Oak Ridge, and Savannah River. Hydro-fracture was once used at Oak Ridge, Tennessee, for disposal of waste in slate formations beneath the site. DOE has also closed disposal facilities at Monticello, Utah, Weldon Spring, Missouri, and Fernald, Ohio following completion of site clean up activities.
There are 61 disposal facilities located throughout the U.S. for uranium and thorium mill tailings. Disposal facilities at most these sites are closed and under long term monitoring. Two commercial by-product material disposal facilities are licensed and operating in the U.S. at Clive, Utah, and Andrews, TX.
Spent fuel is stored in government and licensed non-government facilities. The overwhelming majority is located in spent fuel pools within nuclear power plants or independent spent fuel storage facilities (ISFSIs), many of which are located at decommissioned or operating nuclear power plant sites. Nearly 20 percent of all commercial spent fuel assemblies were stored in dry casks at ISFSIs as of December 2007.
Reprocessing Facilities: No commercial reprocessing facilities are in operation. The West Valley reprocessing plant which closed in 1972 is being decommissioned
Long-Term Disposition of HLW and Spent Fuel: The U.S. government is currently developing a new strategy for HLW and spent fuel waste management and disposal as DOE is committed to fulfilling its legal obligations. DOE continues to develop and execute a research and development program that will address critical scientific and technical issues associated with the long-term management and disposal of “used nuclear fuel”. NRC continues its statutory responsibilities and is reviewing a license application for a repository at Yucca Mountain.
The potential shortage of Class B and C LLW disposal capacity requires additional storage solutions: NRC’s strategic assessment of the commercial LLW program resulted in a range of activities to improve the LLW regulatory framework, such as better guidance on extended storage, reconsideration of waste classification to include depleted uranium, and other alternatives for disposal. Furthermore, a license for a new LLW disposal was issued by the State of Texas.
The lack of a repository for Greater-than-Class-C LLW: DOE began to prepare in 2007 on an Environmental Impact Statement (EIS) to dispose of GTCC LLW and other DOE GTCC-like waste. The EIS is considering several DOE and generic commercial sites, and several technologies, such as geologic repositories, intermediate depth boreholes, and enhanced near surface disposal. A report to the U.S. Congress on disposal alternatives and action by Congress is required before a decision can be reached.