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Backgrounder on Nuclear waste

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On this folio:

• High-Level Waste
• Storage and Disposal
• NRC Responsibilities
• Responsibilities of Other Government Agencies
• Low-Level Waste matter
• Mill Tailings

Radioactive (or nuclear) waste material is a byproduct from nuclear reactors, fuel processing plants, hospitals and research facilities. Radioactive waste is as well generated while decommissioning and dismantling nuclear reactors and other nuclear facilities. In that location are two broad classifications: high-level or low-level waste. High-level waste is primarily spent fuel removed from reactors after producing electricity. Low-level waste material comes from reactor operations and from medical, academic, industrial and other commercial uses of radioactive materials.

The NRC regulates the storage and disposal of all commercially generated radioactive wastes in the U.s.. The NRC too regulates high-level wastes generated by the Section of Free energy that are subject to long-term storage and non used for, or office of, research and evolution activities. Regulations establish minimum adequate operation criteria for licensees managing wastes, while providing for flexibility in technological arroyo.

High-Level Waste matter

High-level radioactive waste primarily is uranium fuel that has been used in a nuclear ability reactor and is "spent," or no longer efficient in producing electricity. Spent fuel is thermally hot besides as highly radioactive and requires remote handling and shielding. Nuclear reactor fuel contains ceramic pellets of uranium-235 inside of metal rods. Before these fuel rods are used, they are only slightly radioactive and may be handled without special shielding.

During the fission process, two things happen to the uranium in the fuel. First, uranium atoms split, creating energy that is used to produce electricity. The fission creates radioactive isotopes of lighter elements such every bit cesium-137 and strontium-90. These isotopes, called "fission products," business relationship for most of the heat and penetrating radiations in high-level waste. Second, some uranium atoms capture neutrons produced during fission. These atoms form heavier elements such as plutonium. These heavier-than-uranium, or "transuranic," elements practise not produce near the amount of heat or penetrating radiation that fission products do, but they take much longer to decay. Transuranic wastes, sometimes called TRU, business relationship for most of the radioactive hazard remaining in high-level waste material later one,000 years.

Radioactive isotopes somewhen decay, or disintegrate, to harmless materials. Some isotopes decay in hours or even minutes, but others decay very slowly. Strontium-ninety and cesium-137 have half-lives of about xxx years (half the radioactivity will decay in 30 years). Plutonium-239 has a half-life of 24,000 years.

High-level wastes are chancy because they produce fatal radiations doses during short periods of direct exposure. For example, x years afterwards removal from a reactor, the surface dose rate for a typical spent fuel assembly exceeds 10,000 rem/hour – far greater than the fatal whole-trunk dose for humans of near 500 rem received all at one time. If isotopes from these high-level wastes get into groundwater or rivers, they may enter nutrient bondage. The dose produced through this indirect exposure would exist much smaller than a straight-exposure dose, merely a much larger population could be exposed.

Reprocessing separates residual uranium and plutonium from the fission products. The uranium and plutonium can be used again as fuel. Most of the high-level waste (other than spent fuel) generated over the last 35 years has come from reprocessing fuel from government-owned plutonium production reactors and from naval, research and test reactors. A modest amount of liquid high-level waste was generated from reprocessing commercial power reactor fuel in the 1960s and early on 1970s. In that location is no commercial reprocessing of nuclear power fuel in the Usa at nowadays; almost all existing commercial high-level waste is unreprocessed spent fuel.

Storage and Disposal

All U.South. nuclear power plants store spent nuclear fuel in "spent fuel pools." These pools are made of reinforced concrete several anxiety thick, with steel liners. The water is typically nigh twoscore feet deep and serves both to shield the radiations and cool the rods.

Dry out Cask Storage of Spent Fuel

Every bit the pools virtually chapters, utilities move some of the older spent fuel into "dry cask" storage. These casks are stainless steel canisters surrounded by physical. Fuel is typically cooled at least 5 years in the pool before transfer to cask. NRC has authorized transfer equally early as 3 years; the industry norm is nearly 10 years. The NRC certifies cask designs and licenses dry cask storage facilities for up to 40 years. The certifications and licenses can exist renewed.

The NRC believes spent fuel pools and dry casks both provide adequate protection for public health and condom and the environment. Therefore at that place is no pressing safety or security reason to mandate before transfer of fuel from pool to cask.

Spent fuel storage at power institute sites is considered temporary, with the ultimate goal being permanent disposal. The NRC is currently reviewing two applications for "Consolidated Acting Storage Facilities," in Texas and New Mexico. These facilities would store spent fuel from commercial nuclear power plants until a permanent disposal facility is available.

At this time there are no facilities for permanent disposal of high-level waste. In the Nuclear Waste Policy Act of 1982, amended in 1987, Congress directed the Department of Energy to design and construct an underground geologic repository at Yucca Mountain, Nevada. DOE practical to the NRC for a construction authorization in 2008; however, DOE canceled the project in 2010 before the NRC completed its review. The NRC closed out its review and the associated adjudicatory hearing in 2011. The NRC completed its technical review in 2015 and published a supplement to the Yucca Mount Environmental Bear upon Argument in 2016, in compliance with an appeals courtroom ruling. For more information on this process, encounter the backgrounder on Licensing Yucca Mount.

NRC Responsibilities

The NRC licenses and regulates the receipt and possession of high-level waste matter at privately owned facilities and at certain DOE facilities. The DOE facilities subject to NRC regulation are defined by law to include: (ane) facilities used primarily for receiving and storing high-level waste from activities licensed under the Atomic Energy Act and (2) facilities other than research and development facilities authorized for the express purpose of long-term storage of DOE-generated waste product. Facilities for permanent disposal will require a license from NRC under these provisions.

Currently, facilities at reactor sites and at Morris, Ill., and the Idaho National Engineering science and Ecology Laboratory are licensed by NRC for temporary storage of spent fuel.

By police, the Commission is non authorized to license:

• Receipt or possession of high-level waste used for or function of DOE activities in a DOE research and development facility;
• DOE facilities for the brusque-term storage of high-level waste from DOE activities (such equally  existing DOE high-level waste product storage tanks);
• Operating DOE facilities for the storage or disposal of transuranic contaminated waste matter, foreign high-level waste not resulting from a licensed activity, and low-level wastes;
• Decommissioned DOE facilities, except those covered under Section 202 of the Energy Reorganization Act. (Section 202 authorizes NRC to license certain DOE facilities, including non only the loftier-level waste matter storage facilities noted above, but also certain demonstration reactors);
• DOE high-level waste processing facilities, such as those for solidification, strontium and cesium extraction, and waste product crystallization.

Responsibilities of Other Government Agencies

Other authorities agencies play a role in managing loftier-level waste.

The Section of Free energy plans and carries out programs for condom handling of DOE-generated radioactive wastes, develops waste disposal technologies, and will design, construct and operate disposal facilities for DOE-generated and commercial loftier-level wastes. DOE has completed solidifying the liquid wastes that are currently in storage at W Valley in New York. The Nuclear Waste matter Policy Act of 1982 sets specific roles and schedules for the DOE to follow in developing high-level waste matter repositories. (The repositories will be licensed past the NRC.)

The Environmental Protection Agency develops ecology standards and federal radiation protection guidance for offsite radiation due to the disposal of spent nuclear fuel and high-level and transuranic radioactive wastes. The standards limit the corporeality of radioactivity entering the biosphere outside the boundaries of the facility, and besides limit the radiation exposure to the public from management of spent fuel and waste prior to disposal. The guidance establishes criteria for disposing of waste.

The Department of Transportation regulates both the packaging and railroad vehicle of all hazardous materials including radioactive waste matter. Packaging must meet NRC regulations, which are uniform with internationally developed standards, and the package design must be reviewed and certified by the NRC. DOT sets limits for external radiation levels and contamination, and controls the mechanical condition of carrier equipment and qualifications of carrier personnel.

The Department of the Interior, through the U.S. Geological Survey, conducts laboratory and field geologic investigations in back up of DOE's waste product disposal programs and collaborates with DOE on the earth science technical activities. The Bureau of Country Management, within DOI, manages certain public lands. DOI may withdraw such public lands for the limited sectional use of DOE in support of nuclear waste disposal actions.

Depression-Level Waste

Low-level wastes, generally defined equally radioactive wastes other than high-level and wastes from uranium recovery operations, are commonly tending of in nigh-surface facilities rather than in a geologic repository. There is no intent to recover the wastes once they are tending of.

Low-level waste includes items that have get contaminated with radioactive cloth or take become radioactive through exposure to neutron radiations. This waste product typically consists of contaminated protective shoe covers and clothing, wiping rags, mops, filters, reactor water treatment residues, equipment and tools, luminous dials, medical tubes, swabs, injection needles, syringes, and laboratory beast carcasses and tissues. The radioactivity tin can range from simply above background levels constitute in nature to much higher levels in certain cases, such every bit from parts from inside the reactor vessel in a nuclear power constitute.

Low-level waste is typically stored on-site by licensees, either until information technology has decayed abroad and can be disposed of as ordinary trash, or until amounts are large enough for shipment to a low-level waste disposal site in approved containers.

The NRC's regulations (x CFR Part 61) establish procedures, criteria, terms and conditions for licensing low-level waste disposal sites. Office 61 besides provides the ground for Agreement State regulations, since state rules must be compatible with NRC requirements. Additionally, licensees may use 10 CFR xx.2002 to dispose of low-level wastes that typically are a small fraction of the Class A limits in Part 61. The extensive controls in Role 61 are not needed to ensure protection of public health and safety and the surround from such wastes.

There take been 8 operating commercial facilities in the United States licensed to dispose of low-level radioactive wastes. They are located at (ane) West Valley, New York; (2) Maxey Flats near Morehead, Ky.; (3) Sheffield, Sick.; (4) Beatty, Nev.; (five) Hanford, Wash.; (6) Clive, Utah; (7) Barnwell, Due south.C.; and (viii) Andrews, Texas. At the present time, only the latter four sites are receiving waste product for disposal; they are regulated by the states. Burial of transuranic waste matter is limited at all of the sites. Transuranic waste matter includes material contaminated with radioactive elements (eastward.g., neptunium, americium, plutonium) that are artificially made and is produced primarily from reprocessing spent fuel and from employ of plutonium in fabrication of nuclear weapons.

Manufactory Tailings

Another type of radioactive waste consists of tailings generated during the milling of sure ores to extract uranium or thorium. These wastes accept relatively low concentrations of radioactive materials with long half-lives. Tailings comprise radium (which, through radioactive disuse, becomes radon), thorium, and pocket-size residual amounts of uranium left over from the milling process. Part twoscore Appendix A of the NRC'southward regulations sets procedures and criteria for disposing of manufacturing plant tailings and maintaining the disposal site.

June 2019

Page Last Reviewed/Updated Tuesday, July 23, 2019

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Source: https://www.nrc.gov/reading-rm/doc-collections/fact-sheets/radwaste.html

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