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I~ow-Activity Waste Overview This chapter summarizes current Tow-activity radioactive waste (LAW) manage- ment and regulatory practices in the United States. The first section provides information on the characteristics, inventories, and regulatory controls for wastes in each of the cate- gories introduced in Chapter 1. The second section provides a perspective on the radio- logical hazards of these wastes. The final section describes currently available disposal sites ant! disposal practices, with more cletailed descriptions given in Appendix D. ~ developing this chapter the committee has focused on the relevant information that led to its findings, rather than reproducing the detailed summary information available else- where.1 Among the wastes described in this chapter, low-level wastes (FEW) from De- partment of Energy (DOE) and commercial nuclear facilities have received the most at- tention from regulators and the public.2 LLW in the form of debris, rubble, and contaminated soils from facility decommissioning and site cleanup constitute much larger volumes than LLW from operational facilities but generally contain very low concentra- tions of radioactive material. Discrete radioactive sources that are no longer useful also meet the definition of LLW even though they may contain highly concentrated radioac- tive material. Although similar in their characteristics, DOE "defense" LLW and com- mercial LLW are generally managed and regulated separately according to their respective origins in the DOE or private sector. Tailings and other wastes from mining and processing uranium and thorium ores have been produced in very large quantities. Like LLW, uranium and thorium wastes are subject to the Atomic Energy Act (AEA), but concern about them has been limited mainly to populations living around mining ant! milling sitesincluding Native Ameri- cans. Non-nuclear enterprises such as mineral recovery and water treatment produce equally large or larger volumes of wastes that contain the same naturally occurring radio- ~ Detailed summary information is available from DOE, 1999, 2001, 2003, the Manifest In- formation Management System (MIMS) at ~http://mims.apps.em.doe.gov>, and the Central Inter- net Database (CID) . Note that DOE 1999, 2003, and MIMS provide commercial-sector data. 2 Low-level wastes fall under the Atomic Energy Act. They are defined in the Nuclear Waste Policy Act of 1982 by exclusion, namely waste that is not spent fuel, high-level waste from fuel reprocessing, transuranic waste, or 1 1 e.~2) byproduct material (see Chapter 2~. 25

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active materials (NORM) as uranium and thorium wastes. NORM wastes are not subject to the AEA, ant! there is no consistent system for regulating them. COMMERCIAL LOW-LEVEL WASTE Commercial LLW comes from nuclear power facilities and other industrial, medical, and research applications. Typical examples include protective shoe coverings and clothing, mops, rags, equipment and tools, laboratory apparatus, process equipment, reactor water treatment residues, non-fuel-bearing hardware, and some decontamination and decommissioning wastes. Low-leve] radioactive wastes are produced in essentially every state. With a few exceptions, the radionuclicles container! in commercial LLW are relatively short-livec! fission products. The ~ 978 revision of the AEA gave the Nuclear Regulatory Commission (USN8C) authority to regulate wastes from the private sector. Defense LLW becomes subject to USNRC regulations if it is shipped for disposal in a commercial facility. In its regulations governing the disposal of commercial low-level waste, the USNRC defines three classes (A the least hazardous -B. and C) based largely on the concentrations and half-lives of radionuclides in the waste. High or essentially unrestricted concentrations of radionuclides with half-lives less than 5 years are allowed, concentrations of some spe- cific fission and activation products with longer half-lives are restricted, and concentra- tions of transuranic nuclides with half-lives greater than 5 years are limited to 100 nanocuries/gram (see Appendix B. Tables B. 1 and B.21. The vast majority of the volume of commercial low-level waste consists of the least hazardous USNRC Class A waste. The Manifest Information Management System (MIMS) provides information on waste shipments to commercial disposal facilities (Barnwell, South Carolina; Clive, Utah; and Richiand, Washington, discussed later in this chapter).3 According to MIMS, ap- proximately 600,000 cubic meters of waste containing almost 9 million curies of radioac- tivity were disposed from 1989 through 2001 (see Figures 3.1 and 3.2~. The vast majority of the waste, some 85 percent of the volume and the curies, came from nuclear utilities. Wastes from other industries amounted to about 7 percent of the volume and the curies. Wastes received from DOE sites made up most of the remainder. Waste from medical and academic origins amounted to less than 1 percent of the volumes and curies disposed. The Bend toward volume reduction begun in the mid ~ 990s resulted from signifi- cant efforts to reduce waste production and to further reduce volume by compaction and super compaction of waste. The substantial volume increase beginning in 2000 is the result of large amounts of slightly contaminated soils, debris, and rubble that Envirocare of Utah began receiving in that year. The waste sent to Envirocare, however, contained less that ~ percent of the curies disposed. 3 See . DOE does not assure the quality of this information. 26 Interim Report

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120000 ~ 100000 E Q 80000 60000 40000 u, ._ ~ 20000 - o 1 1 1 _ ~ , , _. , . - I I ~ - r --or 1 - I ---r----8 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 Year Figure 3.1. Volumes of Low-Level Waste Disposed at Commercial Sites. Upper bars beginning in 1998 are very-low-level wastes received at Envirocare of Utah. Source: MIMS, 20003. 2000 1 800 1600 - u, ~5 3 1 400 t in o in ._ in = 1200 1000 800 600 400 200 o _ 1 1 1 1 1 1 1 1 ~ 1 1 1 1 1 1 1 1 1 1 1 1 1 989 1 990 1 991 1 992 1 993 1 994 1 995 1 996 1 997 1 998 1 999 2000 2001 Year Figure 3.2 Curies of Low-Level Waste Disposed at Commercial Sites. Source: MIMS, 20003. Interim Report 27

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DOE DEFENSE LOW-LEVEL WASTE Defense T. 'LW has been generated in the course of producing or using special nu- clear materials throughout the DOE complex, including fuel fabrication, reactor opera- tion, and isotope separation ant! enrichment, and it continues to be produced in site cleanup work.4 In general terms, DOE LLW is quite similar to commercial LINT except that some ractionuclides specific to nuclear fuel reprocessing appear in higher quantities. For example, some DOE LLW contains transuranic isotopes, mainly plutonium, at con- centrations between 10 and 100 nanocuries per gram (nCi/g). Cumulatively through fiscal year (FY) 1999, DOE had disposed an estimated to- tal volume of 5.S million cubic meters of low-level waste and contaminated media containing almost 50 million curies. In FY-2000, DOE treated about 833,000 cubic meters of LLW and disposer! about 40,000 cubic meters. DOE clisposed of another 29,000 cubic meters in commercial facilities. The treater! and subsequently ctisposec3 waste volumes were about equal to new additions, so the beginning and year-enc! inventory remained almost constant at about 146,000 cubic meters. DOE estimates that another 2 million cubic meters wait be disposed by 2070 (DOE, 2001; CID, 20031. DOE's main sites that generate and dispose of LLW are shown in Figure 3.3. As notes! in Chapter 2, DOE is self-regulating for wastes generated and clisposec3 at its sites. Onsite wastes that do not i it into other waste categories clefinect by Order 435.1 are managed and disposed as LLW. DOE LLW shipped to commercial facilities is subject to the USNRC's or the Agreement State's commercial waste regulations. SLIGHTLY RADIOACTIVE SOLID MATERIALS Nuclear facility decommissioning produces debris, rubble, and contaminated soil characterizes! by large volumes of materials having small quantities of radioactive con- taminationincluding concrete, plastics, metals and other building materials, equipment, and packaging. A previous stu(ly (NRC, 2002a) introduced the term "slightly radioactive solid materials" (SRSM) to describe these materials. These wastes are produced in both the DOE and commercial sectors. Decommissioning the existing commercial power reactor facilities may generate up to about ~ million cubic meters of SRSM, about 90 percent being concrete. These same facilities may also yield! about a million metric tons of metallic SRSM (NRC, 2002a). DOE estimates that about 700 of its reactor ant! processing facilities will be fully decommissioned! in the course of site cleanup (NRC, 1998~. DOE also estimates that about 82 ~ ,000 cubic meters of solid contaminated media may be excavated during its site cleanup activities between 2000 and 2010 (DOE, 2001~. Currently these wastes are regulated and disposer! as USNRC Class A wastes, which means they must be disposed in USNRC licensed facilities (or their equivalent at DOE sites). However, these wastes usually contain very small amounts of radioactivity. Debris and rubble sent to Envirocare amounted! to about 90 percent of the total LLW vol- ume disposed in 2000, but amounted to only about ~ percent of the radioactivity (MIMS, 2003~. The US~C and its Agreement States have allowed alternative disposal 4 Depa~l~ent of Defense low-activity waste is not discussed in this report. This waste is man- aged and disposed by contractors as commercial waste regulated by the USNRC unless it is classi- fied for security purposes. Classified waste is managed and disposed by DOE. 28 Interim Report

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FIN 1 , /81 1 ~ - - ~ - ~ f far co c ~ o a cI ~ D_ cn cO o it' t~ u) v v, 5 o to ~8 cot cot ~ O 0~6 .~0 ~ v: Interim Report 29

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pathways (e.g., in permitted landfills) on a case-by-case basis (USN~C, 2002). Both the Environmental Protection Agency (EPA) and USNBC are investigating alternative dispo- sition options for these wastes. DISCRETE RADIATION SOURCES Discrete radiation sources usually consist of a radioactive material in a leak-tight metal casing. The amount and type of radioactive material used (e.g., Co-60, Sr-90, Cs- ~ 3 7, If- ~ 92, Cf-252, Am-24 ~ ~ determine the type and intensity of emitted radiation. Sealed sources have essential uses in medical diagnostics and therapy, industry (radiog- raphy, well logging), and research. Over the course of time, radioactive decay may re- duce their intensity below a useful level, or the application may become obsolete- such as the use of Ra-226 in medicine or Cs-137 irradiators. Unused radioactive sources are often referred to as "spent" sealed sources although they may continue to present a sig- nificant radiation hazard if not properly stored or disposed (IAEA, 2001~. Sealed sources in commercial use are licensed by the USNRC or an Agreement State. DOE controls sealed sources used at its sites. As a practical matter, however, the identifying marks and records on many sealed sources, especially older sources, are sometimes lost and the sources themselves may become lost or "orphaned." According to some estimates there are over 30,000 orphan sources in the United States. ~ cooperation with the Conference of Radiation Control Program Directors (CRCPD), the EPA, USNRC, and DOE are funding a program to assist states to retrieve and securely dispose of orphan sources.5 While many discrete sources clearly are not low-activi~ materials, they meet the Nuclear Waste Policy Act definition of LLW (see Chapter 24. Their designation as LLW generally works in practice because the radionuclides in these sources typically have half- lives of a few decades or less,6 and their small volume allows them to be safely stored in shielded containers. Regulatory authorities in most countries allow their disposal in near- surface facilities designed for LLW. Nonetheless, these sources represent the opposite extreme from the large volumes and Tow activities that characterize most other wastes considered in this report. URANIUM MINING ANI) PROCESSING WASTES Beginning with the Manhattan Project in 1942, uranium and thorium ores were mined and processed on a massive industrial scale (DOE, 1996). Initial ore production was dedicated to the manufacture of material for nuclear weapons; subsequent production supported the nuclear power industry as well. From the earliest days of the weapons pro- gram into the Cold War period, the government and its contractors, while maintaining the urgent pace of the program, developed an irregular pattern of waste retention and storage. The residues from recovering and processing uranium and thorium were stored in outdoor s See OCR for page 25
piles for later management or sometimes buried on site. In some cases tailings have been used inappropriately as construction materials (NRC, 1986~. The racliological hazards of these wastes arise from decay of naturally occurring uranium and thorium isotopes and their daughter isotopes (see Table 3.1~. Beginning with Th-232, U-23S, or U-235, radioactive decay produces a series of other radioisotopes (daughters) reacting to the eventual formation of stable (non-radioactive) isotopes. The half-lives of the thorium and uranium parent isotopes are extremely longcomparable to the age of the Earth, which is why they still exist in nature. The radioactivity associated with wastes containing these isotopes is therefore Tow but persistent. Raclon-222, a daughter product of U-23 ~ is of particular concern because it is gaseous and can diffuse from tailings piles unless they are properly capped. Uranium and thorium processing tailings wastes are clefined as byproduct mate- rial in section ~ le.~2) of the AEA (see Chapter 2~. Typical tailings piles range in size from tens of thousands to over three million cubic meters (DOE, 2003~. If these wastes were generated at facilities uncler license by the USNRC in 1978 or thereafter, they are manages! under the Uranium Mill Tailings Radiation Control Act (UMTRCA) of ~ 978. Both the EPA and the USNRC regulate aspects of UMTRCA site remecliation and waste disposal. The USNRC has `determined that it does not have authority to regulate uranium mining and processing wastes at facilities that were not under USNRC license at the time of passage of UMTRCA. Some of these wastes, generated between the start of the Man- hattan Project and 1978 and related to the nation's early atomic weapons program, are managed under the Formerly Used Sites Remediation Action Program (FUSRAP) estab- lishecl under the ALA. FUSRAP cleanups are conclucte(1 by the Anny Corps of Engineers (see Siclebar 3. ~ ). The DOE manages uranium-contaminatec! wastes on its sites. TABLE 3.1 Uranium, Thorium and Their Lonaer-Lived Radioactive ne.~.nv Prn~lllrt~ Isotope Half-life Isotope Half-life Isotope Half-life U-238 4.47xlO9 y U-235 7.04xlO~ y Th-232 1.41x10~ y Th-234 24.1 d Pa-231 3.28x104 y Ra-228 5.75 y U-234 2.46xlOs y Ac-227 21.77y Th-228 1.91 y Th-230 7.54x104 y Ra-223 11.44d Pb-208 stable Ra-226 1600 y Pb-207 stable Rn-222 3.82 d Pb-210 22.3 y Po-210 138.4 d Pb-206 stable . .. . Note: y= years; d = days SOURCE: NRC, 1999a - Interim Report 31

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SIDEBAR 3.1 FUSRAP and UMTRCA: TWO PROGRAMS FOR THE SAME MATERIALS The Formerly Utilized Sites Remedial Action Program (FUSRAP) is an environmental program established in March 1974 by the Atomic Energy Commission under the authority of the Atomic Energy Act of 1954. The program was created to identify, investigate, and take appropriate cleanup action at sites with radioactive contamination resulting from the nation's early atomic weapons program. Cleanup at FUSRAP sites primarily involves building debris and soils con- taminated with uranium and thorium. The Department of Energy (DOE) assumed responsibility for FUSRAP in 1977. Initially records were reviewed and surveys were performed on more than 400 sites connected with the atomic weapons program. The DOE began limited cleanups of some sites in 1979 and started major re- medial actions in 1981; cleanup of 25 sites was completed by 1997. Congress transferred responsibility for the administration and execution of FUSRAP to the Army Corps of Engineers as part of the Energy and Water Development Appropriations Act of 1998. While the Corps was assigned the responsibility for the 21 sites in the program at the time of the transfer, the DOE continues to determine the eligibility of new sites for the program. The Corps conducts cleanups under the framework of the Comprehensive Environmental Resnonse Comnen- sation, and Liability Act of 1980 (CERCLA), as amended. ~~ 7 -----rem The Uranium Mill Tailings Radiation Control Act (UMTRCA) controls uranium- and thorium- contaminated wastes produced after 1978. Title I of UMTRCA deals with DOE remedial action programs at former mill tailings sites, and Title II deals with non-DOE mill tailings sites and ura- nium mining sites that are licensed by the USNRC or an Agreement State according to USNRC regulations (see Table 2.1 in Chapter 2 for details on UMTRCA). With FUSRAP and UMTRCA, wastes with similar radiological hazards arising mostly from ura- nium, thorium, and their radioactive decay products fall into different regulatory and management boxes depending on whether the materials were generated at facilities that were under license by the USNRC at the time of passage of UMTRCA in 1978. This statutory construct has led to a novel approach to managing pre- 1978 ore processing residuals within FUSRAP. If the USNRC approves materials from a FUSRAP site as alternate feed material to be processed at a uranium mill for further exaction of uranium, albeit uneconomically, the residues fall under UMTRCA (because they arose after 1978) and can be put in the molly tailings pile after processing. Some refer to this as "sham processing," an act to reclassify the waste for disposalalthough from a technical standpoint the FUSRAP waste may in fact be the same as the tailings waste and the USNRC has ruled that economics is not a factor in approving alternate feed material. However, if the FUSRAP waste (or other material) is not 1 left) in the clear sense of the AEA, then there are significant administrative hurdles in the way of direct disposal of this material into the tailings impoundment of an UMTRCA facility. NORM AND TENORl\l WASTES Naturally occurring radioactive materials (NORM) arise in many mineral extrac- tion operations and are often discarded as wastes examples include phosphate industry residues, scale and sludge from of] and gas production, non-uranium mining tailings, and coal ash residues (see Table 3.2~. The materials are referred to as technologically 32 Interim Report

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TABLE 3.2 Domestic Processes that Generate NORM Waste Process Waste description Radionuclide Estimated Major generator concentration waste genera- locations (picocuries per lion (million gram) metric tons per year) Soils in the (Benchmark for 0.2 - 4.2 United States typical background) Coal combustion Fly ash 2 - 9.7 44 Midwestern and South Atlantic states Bottom ash and slag 1.6 - 7.7 17 Geothermal en- Solids 10 - 250 0.05 California ergy production Metal mining Slag, leachate and Mostly Midwestern and processing tailings from: and Western states -Large volume in- 0.7 - 83 1000 dustries* -Special application 3.9 - 45 0.47 metals -Rare earth metals 5.7 - 3,200 0.002 Municipalwaste Sludge** 1.3 - 11,600 3 All, especially treatment (picocuries per North Central and liter) Atlantic Coastal Plain Oil and natural Scale and sludge Background to 2.6 States where petro- gas production over 100,000 leum or natural gas is produced or processed Phosphate min- Oretailings and 7-55 48 Florida, Idaho, and ing and fertilizer phosphogypsum other states in the production*** (calcium sulfate West and Southeast * Such as iron and copper mining. **Filters typically have concentrations of 40,000 picocuries/gram but arise in much smaller volumes. ***Phosphate fertilizer volumes are about one order of magnitude less, with the same concentra- tions of radionuclides. SOURCES: DOE, 1997, and ~http://www.tenorm.com> Interim Report 33

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enhanced NORM, or TENORM if their concentrations of radioactive matenals are in- creased above naturally occurring levels. Sludge or filter media from water and wastewa- ter treatment are good examples of TENORM waste. Estimates of the NORM and TENORM inventories from U.S. industries exceed 60 billion tons (NRC, 1999a). The radionuclides in NORM waste arise mainly from uranium and thorium series isotopes (see Table 3.11. NORM waste is therefore radiologically similar to uranium mining and milling wastes, although some radioisotope concentrations may differ. Unlike uranium and thorium wastes, NORM is not a byproduct of the production of fis- sionable materials and is not controlled by the AEA. Except for Department of Transpor- tation regulations on transportation of radioactive materials, for the most part NORM is not regulated by federal agencies but rather by states.7 As noted in Chapter 2, there is considerable variation among states, which often regulate non-AEA materials collectively as "NARM" (see Siclebar 3.2~. In Agreement States the same state agencies that have authority for AEA materials usually regulate NORM materials as well. States that regulate NORM specify concentrations of radium below which materials are exempt from regulation as waste, but the concentrations vary from state to state. Recognizing these disparities, the Conference of Radiation Control Program Directors has developed suggester! state regulations for TENORM.8 HAZARD CONSIDERATIONS FOR LOW-ACTIVITY WASTE The radiological hazards of LAW depend on both its level of radioactivity ant! its longevity. As noted by the Board on Radioactive Waste Management at the outset of this study (see Chapter 1), the radiological hazard of LAW is typically much less than that for spent nuclear fuel or high-level reprocessing waste, but the hazard may persist for very long periods. Chapter 4 will summarize the committee' s view of these risks and where they fall within the current regulatory scheme. While the regulatory system was devel- oped primarily to control radiological risks of LAW the focus of this reportnon- radiological hazards are also important. The radioactivity in any material depends on the concentration of radioactive at- oms present and their half-lives (see Sidebar 3.3~. Low-activity wastes are oilmen only slightly contaminated so the radioactivity is very low. However, LAW may contain a substantial concentration of radionuclides with very long half-lives (e.g., uranium and thorium wastes, NORM wastes). The radioactivity is low, but the hazard does not dimin- ish appreciably with time. ~ addition, DOE ant! USNRC regulations allow some wastes with relatively high radioactivity to be managed and disposed as LLW. These wastes contain fission or activation products with relatively short half-lives so their radioactivity diminishes rather rapidly~ver time scales of decades to centuries. ' If sites containing NORM are listed on the National Priorities List they are subject to CERCLA, and the management of the NORM wastes generated at the site are governed by appli- cable or relevant and appropriate requirements (ARARS), which are specified on a case-by-case basis in each Record of Decision (ROD). When there is no ARAR or when the ARAR is consid- ered to be non-protective, a lifetime risk range of 10-4 to 1 o-6 is used to establish the standard. See . 34 Interim Report

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SIDEBAR 3.2 NARM, NORM, and TENORM These acronyms refer to an assortment of materials that are not subject to federal regulation under the AEA, and thus are regulated by the individual states. In many state regulations and elsewhere (e.g., NCRP, 2002) they are referred to collectively as NARM (nah~raliv occurring ~nr1 ~r.r.ele.r; tor-produced adioactive materials). \_ , ~ ~ c, wand ~ . , ~ Particle accelerators are often used to produce isotopes for medical and research purposes. In addi- tion to these products, components of the accelerator itself may become radioactive. According to the EPA there are no firm estimates of the amount of accelerator-produced wastes, but it is gener- ally accepted that the volume of these wastes containing isotopes with half-lives greater than one year (i.e., long enough to present waste management challenges) is very small compared to other low-activity wastes. The committee paid little attention to these materials. For completeness, however, concentrated materials with longer half-lives, e.g., Co-60, Ir-192, can be included as discrete sources in the committee's categorization of low-activity waste. Otherwise the waste will be radiologically similar to defense or commercial low-level waste. Naturally occurring radioactive materials (NORM) are a subset of NARM. They contain radioac- tive elements such as uranium and thorium, which were present when the Earth was formed, their radioactive decay products,* and some isotopes that are produced by cosmic rays from the sun such as C- 14. In its categorization the committee chose to distinguish wastes in which NORM is coincidental to recovery of mineral resources Omening, oil, gas) from wastes produced in recovery of uranium and thorium for nuclear purposes. Uranium and thorium mining and processing wastes are covered by the AEA. Most mineral recovery operations tend to concentrate NORM to produce TENORM- technologically enhanced NORM. Examples are pipe scale, tailings piles, sludges, and filters. Water purification and treatment also produce TENORM. While noting that EPA and state regu- lations generally address TENORM only; for completeness the committee included both NORM and TENORM together in one category. * 1-A; ')~< ~_1:~_~:..~ IN I ~~ IT an r___ ~_1 1 ~ x ~ 1~a~lulil-^ no, a l~UlU~LlV~ My plOQUUt O1 U-~O OCR for page 25
for LAW. Present requirements placed on waste generators along with the limited num- ber of disposal sites result in transporting large amounts of LAW over long distances. Envirocare of Utah receives very large amounts of slightly contaminates! wastes shipped by rail and truck from all parts of the country. Plans are underway to ship the San Onofre, California, reactor pressure vessel to Barnwell, South Carolinapossibly by sea around South America because the vessel and shipping cask are too large for cross- country rail shipment and too heavy to go through the Panama Canal (St. Onge, 2003) Barnwell is the only disposal facility that can accept Class B or C waste from California (see the following section on clisposal). - SIDEBAR 3.3 RA1)IOACTIVITY IN LOW-ACTIVITY WASTES The radioactivity in any material is proportional to the concentration of radioactive atoms of a given type divided by their half-life: A =kN/t~/2 where A is the number of radioactive disintegrations in a given time typically disintegrations per second (becquerels) or a much larger unit (curies), equal to about 3.7 x10' becquerels; N is the number of radioactive atoms of a given kind (radionuclides) often expressed In units of concentra- tion (e.g., per unit mass or volume of waste); to is the time required for half of the initial number of radionuclides to decay (half-life); and k is a constant equal to about 0.7. Wastes are usually contaminated with more than one radionuclide, so the total radioactivity is the sum of their individual radioactivities. The radioactivity in wastes is typically measured or calcu- lated on the basis of volume (e.g., becquerels per cubic meter). For slightly contaminated wastes (protective clothing, building debris, rubble) the number or concentration of radioactive atoms, N. is relatively small so the activity, A, is small, according to He above equation. Conversely, wastes may contain relatively large concentrations of radionu- clides with long half-lives (uranium residues, NORM). For these wastes the quotient (N / the) is small and the radioactivity, A, is still lowbut it persists for a very long time. LOW-ACTIVITY WASTE DISPOSAL DOE practices onsite treatment and disposal for much of the LAW generated at its major sites, which are depicted in Figure 3.3. Disposal capacity at DOE sites, espe- cially at the Nevada Test Site and Hanford, Washington, appears to be more than acle- quate for future disposal needs (GAO, 2000~. Nevertheless, DOE does make use of commercial treatment ant! clisposal capabilities (described below), when appropriate for cost reduction or to supplement DOE's capabilities. In the commercial sector, there are three sites available for disposal of low- activity wastes: Barnwell, South Carolina, operated by Chem-Nuclear; CTive, Utah, oper- ated by Envirocare of Utah; and within the DOE Hanford site near RichIand, Washing- ton, operated by U.S. Ecology. A fourth facility at Grand View, Idaho, operated by U.S. Ecology and designed for chemically hazardous wastes, is currently receiving FUSRAP waste. Each of these facilities is limiter! in the types and volumes of waste that can be 36 Interim Report

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. disposed. Sidebar 3.4 summarizes commercial waste disposal regulations and practices. Appendix D provicles descriptions of the disposal facilities. Only one disposal facility, at Barnwell, is currently accepting USNRC Class A, B. and C Tow-leve! waste from all states. South Carolina formed the Atlantic Compact (formerly the Northeast Compact) with Connecticut and New Jersey on July I, 2000. Un- cler the Compact, South Carolina can limit the use of the Barnwell facility to the three compact members. A state law enacted in June 2000 phases out acceptance of non- compact waste after 2008. The other existing disposal facility for all three major classes of low-level we.. _ ~ 1 $ ~ ~ ~ * = ~ . ~ IS the Cantors, Washington, site operated by U.S. Ecology. Controlled by the Northwest Compact, the Hanford site will continue taking waste Tom the neighboring Rockv Mn~m- tain Compact (see Table 2.1) under a contract. The Envirocare of Utah facility is available for most Class A wastes generated nationwide. The site's operator, Enviroc are, applied to the state on November 1, 1999, for a license amendment to accept Class B and C waste as well. Utah regulators granted the license amendment. For the amendment to take effect, however, approvals by the state legislature and the governor are required. Envirocare has deferred seeking final state ap- proval in part because of citizens' concerns and non~irlernble nnlitir~1 c!~nciti~rit`, the ``rn~= ~ =~ ~ a ~ _ 711, L~ Eva '1: I ~ _ _ 1 _ ~ . . ~ _ _ _ disposal issues (e.g., a proposed commercial scent file.1 Tarts f~rilit~l near drift on the Goshute reservation). It is notable that no new commercial disposal facilities have been opened since the Envirocare of Utah site opened in 1988. After the Low-Level Waste Policy Act made states responsible for disposal of their low-level wastes and directed the formation of in- terstate compacts, the states and compacts spent about $600 million in mostly failed sit- ing efforts (GAO, 1999, also see Sidebar 2.11. A site at Ward Valley, California, was licensed by U.S. Ecology in 1993, but land transfer issues From the federal to state gov- ernment effectively blocked that site's startup. Recently, however, the Texas legislature and governor have annrove.~1 hills to Lou r~mm`~r~io1 l<~~r_l-~rm1 art ,1;~ 1 :~ 61 state. -< ~ = ~~448~_1 61001 ~11 ~ 11 v~a1 ~ Errs ~~ ~---~ ~~~v~~i ~V-VV-l~V~l Wanly Ul~pUb~1 111 t11~1 Although the specific reasons for the lack of success vary among compacts and states, there are several common threads. One thread is the controversial nature of nu- clear waste disposal, which often manifests itself in the form of skepticism about and op- position to disposal facilities by members of the public and political leaders. Waste generators, compacts, and states have in recent years reassessed their need for disposal facilities and deferred the development of facilities because of the declining vol',me of ~1~ 1~ Hi ~ Id `~_ ~:_1 _' _ r 1 1 In ~ un(1 ~ wastes, me man cost of Developing new disposal facilities and the contin- ued availability of disposal services to most waste generators (GAO, 1999~. Current policies (specifically, surcharges and taxes levied by states that host the three commercial disposal facilities) put into place in the 1980s for managing commercial low-level radioactive waste have led to higher prices to generators. Potential lack of ac- cess to existing disposal capacity due to restrictions by host states creates concerns among generators, especially in view of the planned closing of the Barnwell site to users outside the Atlantic Compact in 2008. The picture for defense low-level waste, much of which is radiologically similar to the civilian waste stream, is very different with access to disposal capacity being assured at a much lower cost (DOE, 2002~. Interim Report 37

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SIDEBAR 3.4 REGULATION AND DISPOSAL OF LLW IN NEAR-SURFACE FACILITIES The USNRC and the states govern the siting, operation, and closure of all low-level waste disposal facilities. The USNRC has set forth requirements to protect people from releases from the site, prevent inadvertent intrusion into the waste, protect workers during operation, and ensure the sta- bility of the site after closure. USNRC regulations for required low-level waste disposal time periods. The USNRC requires that Class A low-level waste be contained for up to 100 years, Class B waste for 300 years, and Class C waste for up to 500 years. USNRC regulations for low-level waste disposal facilities. The USNRC has established techni- cal requirements for shallow land disposal. These requirements include areas, such as wildlife pre- serves, to be avoided; the site must be sufficiently isolated from groundwater and surface water; and the site must not be in an area of geological activity (such as volcanoes or earthquakes). Re- gardless of design, all low-level waste disposal sites use a series of natural and engineered barriers to prevent radioactivity from reaching the environment. There are five designs for building dis- posal facilities: shallow land burial, modular concrete canister, below-ground vault, above-ground vault, and earth-mounded concrete bunker. Waste Treatment. Most LLW including those wastes that are LAW as defined in this report are disposed in 55-gallon drums, B-25 boxes, or other specialized concrete, metal, or sometimes wooden containers. Wastes are prepared by compaction, super compaction, dewatering solidif~ca- tion, consolidation, or other techniques approved by regulators of disposal sites. These require- ments are spelled out in site licenses and waste acceptance plans or waste acceptance criteria. Shallow land burial. Waste containers are placed in long, lined trenches 25 or more feet deep. The trenches are covered with a clay cap or other low-permeability cover, gravel drainage layers, and a topsoil layer. They then are contoured and replanted with vegetation for drainage and ero- sion control. In addition, an intrusion barrier, like a thick concrete slab, is added to Class C waste trenches. The sites are carefully monitored to ensure performance in compliance with the regula- tions. Facilities are sited in an area away from surface water and where travel of any groundwater is slow. Other disposal systems include but are not limited to: Modular concrete canister disposal. This method consists of individual waste containers placed within concrete canisters, which are then disposed in shallow land sites. The array of canisters has an earthen cover. This additional engineered barrier system has been used at the Barnwell, South Carolina, facility since 1995 and has been proposed for Classes B and C disposal at Envirocare. Below-ground vault. This type of disposal uses a sealed structure built of masonry blocks, fabri- cated metal, concrete, or other materials that provide a barrier to prevent waste migration. It has a drainage channel, a clay top layer and a concrete roof 'n k~.~n wafer nice ~ Ore hn~1~f;~] ~~A drainage pad for the concrete vault. ----a -I ~~~ ~ Am V~~1111~ ally a Above-ground vault or engineered berm. This is a reinforced-concrete building that provides isolation on the Earthls surface. Its walls and roof are two to three feet thick' and it has a sloping roof to aid water runoff. Some Canadian utilities use similar above-ground vaults for storing low- level waste for later disposal. For low-activity radioactive waste, above-ground engineered berms provide the same isolation as shallow land burial. Envirocare of Utah uses above-ground en~si- neered berms. SOURCE: NEI