Radiation is used in many different industries, including as fuel for nuclear power plants and in the production of nuclear weapons for national defense. These uses generate nuclear waste, and this waste must be disposed of in safe and effective ways. There are three main types of nuclear waste—high-level, transuranic, and low-level waste—and each type must be disposed of according to its risk to human health and the environment.

Federal agencies regulate, treat, and dispose of nuclear waste. For example, the Department of Energy (DOE) oversees the treatment and disposal of radioactive waste from the nation’s nuclear weapons program; it is also responsible for siting, building, and operating a future geologic repository to dispose of high-level nuclear waste However, there are a number of ways that DOE could improve how it stores, treats, and disposes of this waste.

High-level waste

High-level nuclear waste remains highly radioactive for tens of thousands of years and must be disposed of in such a way that it can be securely isolated for a long period of time.

Civilian high-level waste. The nation has over 80,000 metric tons of spent nuclear fuel from commercial nuclear power plants. DOE is responsible for disposing of this waste in a permanent geologic repository, but has yet to build such a facility. As a result,the amount of spent nuclear fuel stored at nuclear power plants across the country continues to grow by about 2,000 metric tons a year. Meanwhile, the federal government has paid billions of dollars in damages to utilities for failing to dispose of this waste and may potentially have to pay tens of billions of dollars more in coming decades. If DOE were to implement a coordinated outreach strategy, it could better achieve and sustain the public acceptance needed to site, build, and operate a permanent repository for spent nuclear fuel.

The nation has over 80,000 metric tons of spent nuclear fuel from commercial nuclear power plants. DOE is responsible for disposing of this waste in a permanent geologic repository, but has yet to build such a facility. As a result,the amount of spent nuclear fuel stored at nuclear power plants across the country continues to grow by about 2,000 metric tons a year. Meanwhile, the federal government has paid billions of dollars in damages to utilities for failing to dispose of this waste and may potentially have to pay tens of billions of dollars more in coming decades. If DOE were to implement a coordinated outreach strategy, it could better achieve and sustain the public acceptance needed to site, build, and operate a permanent repository for spent nuclear fuel. Defense high-level waste. DOE also oversees the treatment and disposal of about 90 million gallons of radioactive waste from the nation's nuclear weapons program. Most of this waste is stored in tanks at 3 DOE sites. According to federal law, certain high-level mixed waste must be vitrified—a process in which the waste is immobilized in glass—and disposed of in a deep geologic repository. However, DOE estimates that about 90% of the volume of this waste contains about 10 percent of the radioactivity and is therefore considered to be low-activity waste. DOE may be able to reduce certain risks and save tens of billions of dollars by adopting alternative approaches to treating and disposing of a portion of its low-activity radioactive waste at its Hanford Site in Washington State. DOE has also faced challenges designing and building high-level waste treatment facilities at its Idaho National Laboratory, as well as at its Hanford Site.



Moreover, the United States will continue to generate new defense waste as a result of its ongoing weapons program and efforts to modernize the nuclear stockpile is expected to increase by the 2030s. For example, the United States is continuing to manufacture weapons components and is resuming manufacturing plutonium components—which is a capability the nation has not had at more than a demonstration level since the early 1990s—which is a capability the nation has not fully had since the early 1990s.

The Partially Constructed Hanford Pretreatment Facility in Washington State, 2013 and 2020

Transuranic waste

Transuranic nuclear waste is waste contaminated by nuclear elements heavier than uranium, such as diluted plutonium. The United States has only one deep geologic repository for the disposal of defense-related transuranic waste—the Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico. However, DOE does not have sufficient space at WIPP to dispose of all defense transuranic waste and is still recovering from accidents in 2014 that resulted in suspending operations.

Underground tunnel at the geologic repository for defense waste in New Mexico

Low-level waste

Low-level waste may be generated from both civilian and defense activities. Low-level waste is generally defined as waste that is not high-level or transuranic waste. Low-level waste decays rapidly and can typically be disposed of in a near-surface disposal facility. Three gaseous diffusion plants—located near Paducah, Kentucky; Portsmouth, Ohio; and Oak Ridge, Tennessee—at one time enriched uranium for both defense and civilian purposes. However, these plants were rendered obsolete by newer, more efficient technologies. As DOE decontaminates and decommissions these facilities, it generates significant amounts of waste, including building materials and hazardous and radioactive waste removed from equipment and piping. Much of this waste is considered to be low-level waste and must be disposed of at a low-level waste disposal facility. However, DOE’s fund to clean up these plants is likely not large enough—cleanup costs may exceed the amount in this fund by $47 billion.

Uranium Enrichment Processing Building at the Department of Energy’s Former Gaseous Diffusion Plant in Paducah, Kentucky

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