ML18038B025
| ML18038B025 | |
| Person / Time | |
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| Issue date: | 12/31/2017 |
| From: | Couret I L Office of Public Affairs |
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| Meyd. Donald | |
| Shared Package | |
| ML18038B330 | List:
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| References | |
| NUREG 1350 V29 R01 | |
| Download: ML18038B025 (14) | |
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63Photo courtesy: NAC International 64Low-Level Radioactive Waste DisposalLow-level radioactive waste (LLW) includes items contaminated with radioactive material or exposed to neutron radiation. This waste typically consists of contaminated protective shoe covers and clothing, wiping rags, mops, ~lters, reactor water treatment residues, equipment and tools, medical waste, and laboratory animal carcasses and tissue. Some LLW is quite low in radioactivity-even as low as just above background levels found in nature. Some licensees, notably hospitals, store such waste on site until it has decayed and lost most of its radioactivity. Then it can be disposed of as ordinary trash. Other LLW, such as parts of a reactor vessel from a nuclear power plant, is more radioactive and requires special handling. Waste that does not decay fairly quickly is stored until amounts are large enough for shipment to an LLW disposal site in containers approved by DOT and the NRC.Commercial LLW can be disposed of in facilities licensed by either the NRC or Agreement States. The facilities are designed, constructed, and operated to meet NRC safety standards. The facility operator analyzes how the facility will perform in the future based on the environmental characteristics of the site. Current LLW disposal uses shallow land disposal sites with or without concrete vaults (see Figure 32: Low-Level Radioactive Waste Disposal).The NRC classi~es LLW based on its potential hazards. The NRC has speci~ed disposal and waste requirements for three classes of waste-Class A, B, and C-with progressively higher concentrations of radioactive material. Class A waste, the least radioactive, accounts for approximately 96 percent of the total volume of LLW in the United States. Determining the classi~cation of waste is a complex process. A fourth class of LLW, called "greater-than-Class-C waste," is not generally acceptable for near-surface disposal. Under the Low-Level Radioactive Waste Policy Amendments Act of 1985, DOE is responsible for disposal of greater-than-Class-C waste. The volume and radioactivity of waste varies from year to year. Waste volumes currently include several million cubic feet each year from reactor facilities undergoing decommissioning and from cleanup of contaminated sites.The LLW Policy Amendments Act gave the States responsibility for LLW disposal.
The Act authorized States to:
- form regional compacts, with each compact to provide for LLW disposal site access
- manage LLW import to, and export from, a
compact* exclude waste generated outside a compact See Appendix O for regional compacts and closed LLW sites.
65Figure 32. Low-Level Radioactive Waste DisposalThis LLW disposal site accepts waste from States participating in a regional disposal agreement.The States have licensed four active LLW disposal facilities:
- EnergySolutions' Barnwell facility, located in Barnwell, SC-Previously, Barnwell accepted LLW from all U.S. generators of LLW. Barnwell now accepts waste only from the Atlantic Compact States of Connecticut, New Jersey, and South Carolina. The State of South Carolina licensed Barnwell to receive Class A, B, and C waste.
- EnergySolutions' Clive facility, located in Clive, UT-Clive accepts waste from all regions of the United States. The State of Utah licensed Clive for Class A waste only.
- US Ecology's Richland facility, located in Richland, WA, on the Hanford Nuclear Reservation-Richland accepts waste from the Northwest Compact States (Alaska, Hawaii, Idaho, Montana, Oregon, Utah, Washington, and Wyoming) and
the Rocky Mountain Compact States (Colorado, Nevada, and New Mexico). The State of Washington licensed Richland to receive Class A, B, and C waste.
- Waste Control Specialists' Andrews facility, located in Andrews, TX-Andrews accepts waste from the Texas Compact, which consists of Texas and Vermont. It also accepts waste from out-of-the-compact generators on a case-by-case basis.
The State of Texas licensed Andrews to receive Class A, B, and C waste.
66High-Level Radioactive Waste Management Spent Nuclear Fuel Storage Commercial spent nuclear fuel, although highly radioactive, is stored safely and securely throughout the United States. Spent fuel is stored in pools and in dry casks at sites with operating nuclear power reactors. Several storage facilities do not have operating power reactors but are safely storing spent fuel. Waste can be stored safely in pools or casks for 100 years or more. The NRC licenses and regulates the storage of spent fuel, both at commercial nuclear power plants and at separate storage facilities. Most reactor facilities were not designed to store the full amount of spent fuel that the reactors would generate during their operational lives.
Facilities originally planned to store spent fuel temporarily in deep pools of continuously circulating water, which cools the spent fuel assemblies. After a few years, the facilities were expected to send the spent fuel to a reprocessing plant. However, in 1977, the U.S. Government declared a moratorium on reprocessing spent fuel in the United States. Although the Government later lifted the restriction, reprocessing has not resumed in the United States.
See Glossary for fuel reprocessing (recycling).
As a result, facilities expanded their storage capacity by using high-density storage racks in their spent fuel pools. To provide supplemental storage, some fuel assemblies are stored in dry casks on site (see Figure 33: Spent Fuel Generation and Storage after Use). These facilities are called independent spent fuel storage installations (ISFSIs) and are licensed by the NRC. These large casks are typically made of leak-tight, welded, and bolted steel and concrete surrounded by another layer of steel or concrete. The spent fuel sits in the center of the cask in an inert gas. Dry cask storage shields people and the environment from radiation and keeps the spent fuel inside dry and nonreactive (see Figure 34: Dry Storage of Spent Nuclear Fuel). The NRC regulates facilities that store spent fuel in two different ways. The NRC may grant site-speci~c licenses after a safety review of the technical requirements and
operating conditions for an ISFSI. The NRC has issued a general license authorizing nuclear power reactor licensees to store spent fuel on site in dry storage casks that the NRC has certi~ed. Following a similar safety review, the NRC may issue a Certi~cate of Compliance and add the cask to a list of approved systems through
a rulemaking. The agency issues licenses and certi~cates for terms not to exceed 40 years, but they can be renewed for up to an additional 40 years (see Figure 35:
Licensed and Operating Independent Spent Fuel Storage Installations by State).
See Appendices M and N for information about dry spent fuel storage and licensees.
A-Z 67Public Involvement The public can participate in decisions about spent fuel storage, as it can in many licensing and rulemaking decisions. The Atomic Energy Act of 1954, as amended, and the NRC's own regulations call for public hearings about site-speci~c licensing actions and allow the public to comment on certi~cate of compliance rulemakings. Members of the public may also ~le petitions for rulemaking. Additional information on ISFSIs is available on the NRC's Web site (see the Web Link Index).
Spent Nuclear Fuel Disposal The current U.S. policy governing permanent disposal of high-level radioactive waste is de~ned by the Nuclear Waste Policy Act of 1982, as amended, and the
Energy Policy Act of 1992. These acts specify that high-level radioactive waste will be disposed of underground in a deep geologic repository licensed by the NRC. Because the timing of repository availability is uncertain, the NRC looked at potential environmental impacts of storing spent fuel over three possible
timeframes: the short term, which includes 60 years of continued storage after a reactor's operating license has expired; the medium term, or 160 years after license expiration; and inde~nite, which assumes a repository never becomes available. The NRC's ~ndings-that any environmental impacts can be managed-appear in the 2014 report NUREG-2157, "Generic Environmental Impact Statement for Continued Storage of Spent Nuclear Fuel." The NRC adopted those ~ndings into NRC regulations in a continued storage rule. This rule provides an important basis for issuing new or renewed licenses
for nuclear power plants and spent fuel storage facilities.
The NRC holds public meetings around the country, where NRC staff members provide information about the agency's role and mission and about the
performance of area nuclear power plants.
68Figure 33. Spent Fuel Generation and Storage After Use 1A nuclear reactor is powered by enriched uranium-235 fuel. Fission (splitting of atoms) generates heat, which produces steam
that turns turbines to produce electricity. A reactor rated at several hundred megawatts may contain 100 or more tons
of fuel in the form of bullet-
sized pellets loaded into long
metal rods that are bundled together into fuel assemblies.
Pressurized-water reactors (PWRs) contain between
120 and 200 fuel assemblies.
Boiling-water reactors (BWRs) contain between
370 and 800 fuel assemblies.
2After 5-6 years, spent
fuel assemblies (which are typically 14 feet [4.3 meters]
long and which contain nearly 200 fuel rods for PWRs and 80-100 fuel rods for BWRs) are
removed from the reactor and allowed to cool in storage pools.
At this point, the 900-pound (409-kilogram) assemblies
contain only about one-~fth the original amount of uranium-235.
Uranium Fuel Pellet Fuel Rod 69 3Commercial light-water nuclear reactors store spent radioactive fuel in a steel-lined, seismically designed concrete pool under about 40 feet (12.2 meters) of water that provides shielding from radiation. Pumps supply continuously owing water to cool the spent fuel. Extra water for the pool is provided by other pumps that can be powered from an onsite emergency diesel generator.
Support features, such as water-level monitors and radiation detectors, are also in the pool. Spent fuel is stored in the pool until it is transferred to dry casks on site (as shown in Figure 34) or transported off site for
interim storage or disposal.
Uranium Fuel Pellet Fuel Rod 70Figure 34. Dry Storage of Spent Nuclear Fuel 2 The canisters can also be stored in aboveground concrete bunkers, each of which is about the size of a one-car garage.
1 Once the spent fuel has suf~ciently cooled, it is
loaded into special canisters that are designed to hold nuclear fuel assemblies. Water and air are removed. The canister is ~lled with inert gas, welded shut, and rigorously tested for leaks. It is then placed in a cask for storage or transportation.
The dry casks are then loaded onto concrete pads.At nuclear reactors across the country, spent fuel is kept on site, typically above ground, in systems basically similar to the ones shown here.
The NRC reviews and approves the designs of these spent fuel storage systems before they can be used.
71Figure 35.
Licensed and Operating Independent Spent Fuel Storage Installations by StatePENNSYLVANIA Limerick Susquehanna Peach Bottom Beaver Valley Three Mile Island SOUTH CAROLINA Oconee Robinson Catawba Summer TENNESSEE Sequoyah Watts Bar TEXAS Comanche PeakUTAH Private Fuel Storage VERMONT Vermont Yankee VIRGINIA Surry North AnnaWASHINGTON Columbia WISCONSIN Point Beach
Kewaunee LaCrosse ILLINOIS Braidwood Byron GE Hitachi Morris (Wet)
Dresden La Salle Quad Cities
ZionIOWA Duane Arnold LOUISIANA River Bend Waterford MAINE Maine YankeeMARYLAND Calvert Cliffs MASSACHUSETTS Yankee Rowe
Pilgrim MICHIGAN Big Rock Point Palisades
Cook FermiMINNESOTA Monticello Prairie Island MISSISSIPPI Grand Gulf MISSOURI Callaway NEBRASKA Cooper Ft. Calhoun NEW HAMPSHIRE Seabrook NEW JERSEY Hope Creek
Salem Oyster Creek NEW YORK Indian Point FitzPatrick
Ginna Nine Mile PointNORTH CAROLINA Brunswick
McGuire OHIO Davis-Besse Perry OREGON Trojan ALABAMA Browns Ferry Farley ARIZONA Palo Verde ARKANSAS Arkansas Nuclear CALIFORNIA Diablo Canyon Rancho Seco San Onofre Humboldt Bay COLORADO Fort St. Vrain CONNECTICUT Haddam Neck
Millstone FLORIDA St. Lucie Turkey Point GEORGIA Hatch Vogtle IDAHO DOE: TMI-2 (Fuel Debris)
DOE: Idaho Spent Fuel Facility ISFSI Site-Speci~c License (15)
ISFSI General License (63) 34 States have at least one ISFSIAlaska and Hawaii are not pictured and have no sites. Data are current as of July 2017. NRC-abbreviated site names listed. For the most recent information, go to the Dataset Index Web page at https://www.nrc.gov/reading-rm/doc-collections/datasets/
72Transportation The NRC is also involved in the transportation of spent nuclear fuel. The NRC establishes safety and security requirements in collaboration with DOT, certi~es transportation cask designs, and conducts inspections to ensure that requirements are being met. Spent fuel transportation casks are designed to meet the following safety criteria under both normal and accident conditions:
- prevent the loss or dispersion of radioactive contents
- shield everything outside the cask from the radioactivity of the contents
- dissipate the heat from the contents
- prevent nuclear criticality (a self-sustaining nuclear chain reaction) from occurring inside the caskTransportation casks must be designed to survive a sequence of tests, including a 30-foot (9-meter) drop onto an unyielding surface, a puncture test, a fully engul~ng ~re at 1,475 degrees Fahrenheit (802 degrees Celsius) for 30 minutes, and immersion under water. This very severe test sequence, akin to the cask striking a concrete pillar along a highway at high speed and being engulfed in a severe and long-lasting ~re and then falling into a river, simulates conditions more severe than 99 percent of vehicle accidents (see Figure 36: Ensuring Safe Spent
Fuel Shipping Containers).To ensure the safe transportation of spent fuel and other nuclear materials, each year the NRC takes the following actions:
- conducts transportation safety inspections of fuel, reactor, and materials licensees* reviews, evaluates, and certi~es new, renewed, or amended transportation package design applicationsFigure 36.
Ensuring Safe Spent Fuel Shipping Containers The impact (free drop and puncture), ~re, and water immersion tests are considered in sequence to determine their cumulative effects on a given package.
73* conducts inspections of cask vendors and manufacturers to ensure the quality of dry cask design and fabrication
- reviews and evaluates license applications for the export or import of nuclear materialsAdditional information on materials transportation is available on the NRC's Web site (see the Web Link Index).
Decommissioning Decommissioning is the safe removal of a nuclear facility from service and the reduction of residual radioactivity to a level that permits release of the property and termination of the license. NRC rules establish site-release criteria and provide for unrestricted and (under certain conditions) restricted release of a site. The NRC also requires all
licensees to maintain ~nancial assurance that funds will be available when needed for decommissioning. The NRC regulates the decontamination and decommissioning of nuclear power plants, materials and fuel cycle facilities, research and test reactors, and uranium recovery facilities, with the ultimate goal of license termination (see Figure 37: Reactor Decommissioning Overview Timeline).Figure 37. Reactor Decommissioning Overview Timeline See Appendices C, I, and P for licensees undergoing
decommissioning.
74Figure 38.
Power Reactor Decommissioning Status FLORIDA Crystal River 3 ILLINOIS Dresden 1 Zion 1 and 2MARYLAND N.S. Savannah MASSACHUSETTS Yankee Rowe MAINE Maine Yankee MICHIGAN Fermi 1 Big Rock Point NEBRASKA Fort Calhoun NEW YORK Indian Point 1
Shoreham OREGON Trojan PENNSYLVANIA Saxton Peach Bottom 1 Three Mile Island 2SOUTH DAKOTA Path~nder VERMONT Vermont Yankee WISCONSIN LaCrosse Kewaunee CALIFORNIA GE EVESR GE VBWR Humboldt Bay 3 Rancho Seco San Onofre 1 San Onofre 2 and 3 COLORADO Fort St. Vrain (DOE License)
CONNECTICUT Millstone 1 Haddam NeckSAFSTOR DECONISFSI (Independent Spent Fuel Storage Installation) onlyLicense Terminated Decommissioning CompletedAlaska and Hawaii are not pictured and have no sites. Notes: GE Bonus, Hallam, and Piqua decommissioned reactor sites are part of the DOE nuclear legacy. For more information, visit DOE's Of~ce of Legacy Management LM Sites Web page at https://www.energy.gov/lm/sites/lm-sites. CVTR, Elk River, and Shippingport decommissioned reactor sites were either decommissioned before the formation of the NRC or were not licensed by the NRC. Licensees have announced their intention to permanently cease operations for the following: Palisades (2018), Pilgrim (2018), Three Mile Island (2019), Indian Point (2020 and 2021), Oyster Creek (2018), and Diablo Canyon (2025). NRC-abbreviated reactor names are listed. For the most recent information, go to the Dataset Index Web page at https://www.nrc.gov/reading-rm/doc-collections/datasets/
75For commercial power reactors that have ceased operations, the decommissioning process may take up to 60 years. This may include extended periods of inactivity (called SAFSTOR), during which residual radioactivity is allowed to decay, making eventual cleanup easier and more ef~cient. A facility is said to be in DECON when active demolition and decontamination is underway. Active decommissioning of a
nuclear power plant takes about 10 years on average.The NRC terminates approximately 150 materials licenses each year. Most of these license terminations are routine, and the sites require little or no cleanup to meet the NRC's criteria for unrestricted access. The decommissioning program focuses on the termination of licenses for sites involving more complex decommissioning activities (see Figure 38: Power Reactor Decommissioning Status, and Figure 39:
Locations of NRC-Regulated Sites Undergoing Decommissioning).
The Status of the Decommissioning Program-2016 Annual Report (SECY 16-0129) contains additional information on the decommissioning programs of the NRC and Agreement States. More information is on the NRC's Web site (see the Web Link Index).Figure 39.
Locations of NRC-Regulated Sites Undergoing DecommissioningPower Reactor Sites Complex Materials Fuel Cycle FacilitiesResearch and Test Reactors Uranium Recovery SitesNote: For the most recent information, go to the Dataset Index Web page at https://www.nrc.gov/reading-rm/doc-collections/datasets/