United States Environmental Protection Agency Office of Radiation Programs Washington, DC 20460 EPA 520/1-88-009 July 1988 Radiation Waste Package Performance Criteria for Deepsea Disposal of Low-Level Radioactive Waste ------- TECHNICAL REPORT DATA (Please read Instructions on the reverse before completing) 1, REPORT NO. ' 2, EPA-52Q/ 1-88-009 4. TITLE AND SUBTITLE Waste Package Performance Criteria for Deep Sea Di of Low-Level Radionactive Waste 7. AUTHORSS) P. Colombo and M. Fuhrmann 9. PERFORMING ORGANIZATION NAME AND ADDRESS Dept. of Nuclear Energy Brookhaven National Laboratory Upton, Long Island, New Yrok 11973 12. SPONSORING AGENCY NAME AND ADDRESS U. S. EPA Office of Radiation Programs 401 M Street, SW Washington, T)C. PlUfifi YBFCITfl^1? w* S. REPORT DATE -Do-al July» 1988 "f """£ PERFORMING ORGANIZATION CODE 8. PERFORMING ORGANIZATION REPORT NO. 10. PROGRAM ELEMENT NO. 11. CONTRACT/GRANT NO. 13. TYPE OF REPORT AND PERIOD COVERED Final 14. SPONSORING AGENCY CODE 15. SUPPLEMENTARY NOTES 16. ABSTRACT This report presents technical information relevant to the packaging of Low-Level Radioactive Wastes for ocean disposal. Sction 2.2 of the report contains 11 recommended waste package performance criteria. Specifications and rational statement for each criterion are also included. 17. KEY WORDS AND DOCUMENT ANALYSIS a. DESCRIPTORS b.lDENTIFI Radionuclides Radioactive Disposal Package Deep Sea Radiation Waste Ocean 18. DISTRIBUTION STATEMENT 19. SECURI Unclas Release unlimited 20 SECURI ERS/OPEN ENDED TERMS c. COSATI Field/Group TY CLASS (ThisReport) 21. NO. OF PAGES sified 43 TY CLASS (This page) 22. PRICE A93 *>3.&> EPA Form 2220-1 (Rev, 4-77) PREVIOUS EDITION IS OBSOLETE ------- WASTE PACKAGE PERFORMANCE CRITERIA FOR DEEPSEA DISPOSAL OF LOW-LEVEL RADIOACTIVE WASTES By P, Colombo and M. Fuhrmann July 1988 NUCLEAR WASTE RESEARCH GROUP DEPARTMENT OF NUCLEAR ENERGY BROOKHAVEN NATIONAL LABORATORY ASSOCIATED UNIVERSITIES, INC. UPTON, LONG ISLAND, NEW YORK 11973 This report was prepared as an account of work sponsored by The United States Environmental Protection Agency under Interagency Agreement No. AD-89-F-1-558-0 Project Officer Robert S. Dyer Analysis and Support Division Office of Radiation Programs U.S. Environmental Protection Agency Washington, DC 20460 ------- Foreword The Environmental Protection Agency (EPA) was given a Congressional mandate to develop criteria, standards, and regulations governing the ocean disposal of all forms of wastes pursuant to Public Law 92-532, the Marine Protection, Research and Sanctuaries Act of 1972, as amended. In response to this mandate, EPA has initiated a program to develop regulations and criteria to control the ocean disposal of radioactive wastes. The EPA ocean dumping regulations and criteria were issued in the Federal Register on January 11, 1977. These regulations require that high-level radioactive wastes be prohibited from ocean dumping; and all other radioactive materials be contained to prevent their direct dispersion or dilution in ocean waters. Furthermore, these containerized radioactive wastes must decay to environmentally innocuous levels within the life expec- tancy of the container(s) and/or the inert matrix. The United States Congress has had a continuing interest in the question of ocean disposal of low-level wastes (LLW) and, in consequence, has recently approved Public Law (PL) 97-424. This Act amended PL 92-532 to include provisions to specifically consider the structural aspects of each container when evaluating any permit for the ocean disposal of radioactive waste. For the past few years the EPA has been considering the question of suitable packaging of radioactive wastes for sea disposal, both by evaluating the fate of radioactive waste packages dumped at formerly used United States ocean dumpsites, and considering how past packaging designs might be improved. Although the EPA has not received a request for a permit to dispose of LLW in the ocean, it is incumbent on vhe Agency to develop the criteria necessary to evaluate permit requests. For determining whether any particular containment system or waste packaging system is adequate, it is necessary to establish a set of performance criteria or guidelines against which a particular packaging system can be evaluated. The following report, prepared by the Nuclear Waste Research Group of the Brookhaven National Laboratory, contains recommendations to the Environmental Protection Agency on packaging performance guidelines and criteria. The performance criteria present requirements for the behavior of the waste in combination with its immobilization agent and outer container in a deepsea environment. It is expected that some of the criteria given in this report may be modified or amended, or new criteria added as more technical information becomes available. The Environmental Protection Agency requests agencies and individuals to provide the Agency with any comments and suggestions pertinent to improving the document and the recommendations contained therein. Such comments or suggestions should be submitted to Mr. David E. Janes, Director, Analysis and Support Division, Office of Radiation Programs (ANR-461), Washington, DC 20460. Richard J./yGuimond, Director Office of 'Radiation Programs ------- Preface This report presents technical information relevant to the packaging of low-level radioactive wastes (LLW) for ocean disposal. Section 2.2 of the report contains 11 recommended waste package performance criteria. Specifications and rationale statements for each criterion are also included. The recommended criteria were developed in response to Environmental Protection Agency responsibilities under PL 92-532 and PL 97-424 (see Foreword and Section 1.1). The Agency's existing (1977) Ocean Dumping Regulations contain no waste package performance criteria for LLW. Accordingly, the Agency is now evaluating these recommended criteria. v Preceding page blank ------- 1. INTRODUCTION 1.1 Background Sea disposal of low-level radioactive waste began in the United States in 1946, and was placed under the licensing authority of the Atomic Energy Commission (AEC). In 1962, the first commercial shallow-land disposal site was licensed in Beatty, Nevada. As land disposal operations expanded, ocean disposal was sharply reduced. The practice stopped completely in 1970 upon the recommendations of the Council on Environmental Quality in a Report to the President [1]. Most of the waste disposed of at sea was packaged in second-hand or reconditioned 55-gallon drums filled with cement so that the average package density was sufficiently greater than that of sea water to ensure sinking. It was assumed that all the contents would eventually be released since the packages were not designed or required to remain intact for sustained periods of time after descent to the ocean bottom [2]. In 1965, the Nuclear Energy Agency (NEA) of the Organization for Economic Cooperation and Development (OECD), in collaboration with a number of interested countries, undertook a series of studies of the practicability of joint sea disposal operations for low-level radioactive wastes. These studies led to the formulation of a number of conditions relating to the selection of suitable disposal areas, the design of waste containers and the selection of ships suitable for disposal operations. Procedures were also adopted for conducting and supervising these operations to prevent unacceptable radioactive contami- nation. On the basis of these studies, NEA sponsored the first international sea disposal operation for radioactive waste in 1967. Five OECD/NEA Member countries (Belgium, France, the Federal Republic of Germany, the Netherlands and the United Kingdom) participated in this first sea disposal operation under international supervision. During the next internationally supervised sea disposal operation in 1969, Italy, Sweden and Switzer- land also participated while the Federal Republic of Germany abstained. Between 1971 and 1983, only Belgium, the Netherlands, Switzerland and the United Kingdom have used the sea disposal option. Recently, there has been renewed interest in ocean disposal, both in this country and abroad, as a waste management alternative to land burial. It is currently under review in several European countries and in Japan as a viable method for the disposal of other than high-level wastes. Although the United States is not presently engaged in ocean disposal of radioactive waste, it has ratified and,is a Contracting Party to the London Dumping Convention (an international agreement to control sources of marine pollution, including the disposal of radioactive materials, in international waters) [3]. Also, the United States is a Member Nation of the International Atomic Energy Agency (IAEA) and a Participating Country to the OECD Council Decision establishing a Multilateral Consultation and Surveillance Mechanism for Sea Dumping of Radioactive Wastes [4]. Thus, the United States shares ------- responsibility with other nations for the consequences of ocean disposal of radioactive wastes. The Marine Protection, Research and Sanctuaries Act of 1972 (PL. 92-532) gives EPA the regulatory responsibility for ocean dumping of all materials, including radioactive waste. This act prohibits the ocean disposal of high-level radioactive waste and requires EPA to control the ocean disposal of all other radioactive waste through the issuance of permits. In implementing its permit authorities, EPA issued an initial set of regulations and criteria in 1973 to control the disposal of material into the ocean waters [5]. It was in these regulations that EPA initially introduced the general requirement of isolation and contain- ment of radioactive waste as the basic operating philosophy. 1.2 Present Packaging Requirements for Ocean Disposal In 1977, EPA issued final revised regulations and criteria concerning the disposal of radioactive wastes in the ocean [6]. In supporting the containment philosophy, the regulations requke that "the radioactive materials must be contained to prevent their direct dispersion or dilution in ocean waters" and that "the materials to be disposed of must decay, decompose or radiodecay to environmentally innocuous materials within the life expectancy of the containers and/or their inert matrix." The IAEA recommendations to the London Dumping Convention emphasize that isolation and containment of radioactive waste be pursued through the use of suitable packaging to keep radioactive releases "as low as reasonably achievable" [7]. Both EPA and IAEA have identified the waste package as the primary barrier for the containment of radioactive waste. However, there appears to be a significant difference in package performance requirements between the two organizations. The terms "innocuous" and "as low as reasonably achievable" are not defined as used in the domestic and international guidance, respectively. In the context of the EPA criteria, "innocuous" might be interpreted as being low concentrations of radionuclides which do not represent a hazard to man if released into the marine environment. On the other hand, "as low as reasonably achievable" refers to limiting radioactive releases, taking into account the state of packag- ing technology, economics of package improvements, public health and sa*ety, and other societal and socioeconomic considerations. The concept proposed in this report envisions the waste disposal system as a series of barriers necessary to ensure that radionuclides are retained or their movement is retarded to prevent a hazard to man. A multibarrier concept is assumed which consists of a "contain- ment system" and an "isolation system." The containment system includes the waste form and the container. In this system each component augments the other. The container protects the waste form from erosion and ------- detrimental affects of prolonged exposures to water, while the waste form provides internal support of the container against the great hydrostatic pressure at disposal depths. The isolation system consists of the containment system as well as the natural barriers against radionuclide transport from the disposal site to man. The sediment and suspended particulates will scavenge most of the remaining activity released after the 200-year lifetime of the container. The small fraction of activity which remains in the water column will be isolated by the residence time of water at the disposal depth and the vertical diffusivity to surface waters. ------- 2. WASTE PACKAGE PERFORMANCE CRITERIA AND SPECIFICATIONS FOR OCEAN DISPOSAL OF LOW-LEVEL RADIOACTIVE WASTES The basic criteria and specifications recommended in this section were recommended in a previous report [8], and are directed specifically toward conditions that influence the performance of the waste package in a marine disposal environment. Therefore, it pre- cludes criteria associated with other aspects of ocean disposal such as site selection, operations, and monitoring. Specific performance criteria are recommended for the waste package and for the individual waste package components which include the waste, the waste form and the container. Where possible, numerical values are listed to quantify criteria. While many of the requirements for the packaging of low-level radioactive wastes (LLW) for land disposal may be applicable to ocean disposal, special conditions of the deep-sea environment require specific considerations regarding packaging and package performance requirements. These special conditions include exposure of the waste package to high hydrostatic pressures and the corrosive sea water environment. 2.1 Assumptions It was necessary to make assumptions to enable the development of waste package performance criteria. These assumptions are: * Existing Federal regulations govern the interim storage, transportation and disposal of radioactive wastes. Waste packages intended for ocean disposal should meet all mini- mum Federal requirements, including relevant United States international treaty commit- ments. Only LLW, as defined in the Low-Level Radioactive Waste Policy Act (PL 96-573), is considered for ocean disposal. The disposal site is located in ocean waters at an average depth greater than 4,000 meters. The waste package is not intended to be routinely retrievable. « Package performance criteria are based upon a multiple barrier concept which considers the contributions of engineered barriers (waste form, container) and natural barriers (water column, physical and geochemical properties of the sediment). ------- 2.2 Waste Package Performance Criteria 2.2.1 Criterion: Specification: Discussion: 2.2.2 Criterion: Specification: Discussion: The package should have adequate density to ensure sinking to the seabed. The specific gravity of the waste package should not be less than 1.2 to ensure sinking to the seabed. A waste package should be sufficiently dense to sink immediately. Although the specific gravity of surface sea water does not exceed 1.03, the package should be sufficiently dense to ensure that its movements during descent and on the seabed are not readily influenced by currents. The waste package should be designed to remain intact upon impact with the sea surface and the seabed. The waste package should be designed to maintain its integrity upon impact with the sea surface and the ocean floor at a minimum calculated and/or measured velocity of 10 meters per second. There should be no loss or dispersion of radionuclides in the event of damage to the waste package upon impact of the waste package with the surface of the ocean or with the seabed. The IAEA, in its transporta- tion regulations [9], requires a drop test with a free fall of 1.2 meters onto an unyielding plate for waste pack- ages weighing less than 5,000 kg. Tests conducted on waste packages that meet IAEA transport regulations have shown that the impact of a package free-falling from a ship height of 9-15 meters to the ocean surface has not resulted in package failure [10, 11]. A waste form falling from the deck of a ship would impact the water at about 10 meters per second. In free fall tests from the water's surface to the ocean bottom (5,000 m), 55-gallon drums, filled with cement and waste, have terminal velocities between 1.7 and 3.1 meters per second [12, 13]. The impact of the package hitting the surface of the water is greater than its impact at the seafloor. There- fore, the package is expected to remain intact upon impact with the ocean floor if it meets the impact test ------- 2.2.3 Criterion: Specification: Discussion: requirements for the free fall from the ship to the surface of the ocean. However, sea floor characteristics should be considered. The container should be capable of maintaining its con- tents until the radionuclides have decayed to acceptable limits, as determined by appropriate regulatory authorities. The waste container should have an expected lifetime in the deepsea environment of 200 years or 10 half-lives of the longest lived radionuclide, whichever is less. A reasonable design objective for the average life ex- pectancy of a LLW container is 200 years. The two radionuclides that are found in large quantities in LLW and have relatively long half-lives (approximately 30 years) are cesium-137 (Cs-137) and strontium-90 (Sr- 90). Decay of these isotopes during a 200-year interval would reduce the activity to 1 percent of the original levels. For example Cs-137 activity from typical solidi- fied power reactor waste forms has been estimated to range from 30 to 300 mCi [14]. This activity will have decayed to between 0.3 and 3.0 mCi in 200 years. Depending on the types of activity contained and their quantity, some containers may not requke a lifetime as long as 200 years. Container failure is defined as the first breach of the container, when sea water first makes contact with the waste form [15]. This is consistent with the EPA philosophy that "radioactive materials must be con- tained to prevent their direct dispersion or dilution in ocean water." Furthermore, "they must decay, decom- pose or radiodecay to environmentally innocuous mate- rial within the life expectancy of the containers and/or their inert matrix" [6]. At container failure (after 200 years), only a small portion of the waste form is likely to be exposed to sea water. This failure mode, in the form of small perforations, has been observed for mild steel containers retrieved from previously used ocean disposal sites [16, 17, 18, 19]. Upon failure of the pri- mary or engineered barrier(s), the secondary or natural barrier(s) become important. At this point the ability of sediment and suspended particulates to adsorb these radionuclides and the residence time of seawater in the ------- 2.2.4 Criterion: Specification: Discussion: deep ocean would tend to minimize any potential haz- ards resulting from transport of released radiormclides from the site. A recent study of the adsorption capacity of sediment collected from the Atlantic 3,800-meter radioactive waste disposal site indicates that 90 percent of the Cs-137 is adsorbed by sediment under well mixed conditions at 5 °C [20, 21]. Modeling studies of dis- solved tracers released at the seafloor indicate that the residence time for deepwater (5,000 meters) in the west- ern basin of the North Atlantic is about 110 years. The vertical extent of dispersion after 100 years is estimated to be 2,200 meters [22]. Container life times can be affected by such factors as the choice of materials, the thickness of the material, and the fabrication technique (e.g., welds, crimps, etc.) [16]. Liquid radioactive waste should be immobilized by suit- able solidification agents. Liquid wastes should be solidified to form a homoge- neous, monolithic, free-standing solid containing no more than 0.5 percent of free or unbound liquid by volume of the waste form. Many radioactive wastes are generated in the form of sludges, wet particulate filter media or wet ion ex- change resins [23]. These materials are not only dispers- ible but the liquid, which may be 80 percent of the volume, is often corrosive. This waste should be solidi- fied to eliminate the concern of dispersibility, to pro- vide material that is not corrosive, to give the waste form the strength to support the container against the hydrostatic pressure of the deep sea and to provide a density greater than 1.2 g/cm3. A variety of materials have been used to solidify wet wastes successfully; among them are portland cement, polymers and bitumen. These materials and the pro- cesses used to solidify low-level waste have been re- viewed [24, 25]. Potential solidification agents for ocean disposal have also been evaluated [26]. The limit of 0.5 percent by volume of free standing liquid is given primarily to ensure proper solidification ------- 2.2.5 Criterion: Specification: Discussion: 2.2.6 Criterion: Specification: Discussion: of die waste. With good production techniques and formulations, a waste form can be produced in which free liquid is below 0.5 percent [27]. Buoyant material should be excluded or treated to pre- clude its movement or separation from the waste form during and after disposal. Buoyant materials should be treated to form a homoge- neous free-standing monolithic solid having a specific gravity of not less than 1.2. A significant percentage of low-level radioactive waste consists of trash such as contaminated items composed of wood, cloth, paper or plastic [23]. Unless properly treated this material could separate from a waste form, in the event of container failure, and float to the surface. Typical treatment processes include incineration and shredding. In addition to the possibility of waste returning to the surface, consideration should be given to the ability of this type of waste to resist the hydrostatic pressure of the deep ocean. Waste forms containing trash have been observed to implode during descent [12] either because of large voids or compressive strengths that were unable o resist pressures even at depths of 1,800 meters. The waste package should be able to withstand the hy- drostatic pressure encountered during and after descent to the seabed. The triaxial compressive strength of a waste package should be 25 percent greater than the pressure encoun- tered at the disposal depth. Uniaxial compressive strength of the package may be measured (the triaxial strength is taken to be 4 times the uniaxial compressive strength [13]). Pressure equalization devices that allow only ingress of water can be used. Tests in Japan indicate that the triaxial compressive strength (which is equivalent to the hydrostatic pressure at any given ocean depth [28]) is 4 times that of the uniaxial co'mpressive strength. For example, at 4,000 meters depth, the triaxial compressive strength of the ------- 2,2.7 Criterion: Specification: Discussion: waste package is 400 kg/cm . This is equivalent to a uniaxial loading of 100 kg/cm". With the addition of a 25 percent safety factor the uniaxial compressive strength of the waste package at 4,000 meters should be 125 kg/cm2 [13]. The waste form and the container should withstand the hydrostatic pressure encountered at the disposal depth. The rigidity of the waste form supports the container against deformation. Therefore, there should be as few voids as possible in the waste form, since larger voids have been observed to cause implosion of the container during descent to the ocean floor [12]. It is conceded that pressure equalization devices are practical in tha» they compensate for deficiencies such as voids in the waste package. Where voids are present there is the possibility of failure resulting in the implo- sion or breaching of the container under normal hydro- static pressures encountered during descent to the ocean floor. The NBA [29] allows pressure equalization de- vices for waste packages disposed at Northeast Atlantic disposal sites. Pressure equalization devices should iso- late seawater, that has entered the container, from the marine environment. The leach rate of the waste form should be as low as reasonably achievable (ALARA). The leach rate for cesium-137 (Cs-137), strontium-90 (Sr-90 ) and cobalt-60 (Co-60), as well as other radionu- clides of concern in the waste, should be no greater than regulatory guidelines as measured by the ANS 16.1 Leach Test for leaching in seawater [30]. Adequate isolation of radionuclides at a LLW ocean disposal site depends on the performance of multiple barriers to retard radionuclide migration. One of the barriers is the waste form, which reduces the release of the waste to seawater in the event of container failure. The ability of the waste form to retain radionuclides is often described in terms of a leach test where the rates of release of elements from the waste form to the environment are measured. ------- The ANS 16.1 Leach Test [30] is a standardized test that is required for licensing of waste forms for disposal at commercial shallow-land burial sites. Results of this test can be expressed as a leach index. The Nuclear Regulatory Commission (NRC) Branch Technical Posi- tion on Waste Form [31] has established a leach index value of 6 for shallow land burial. The three radionu- clides, Cs-137, Sr-90 and Co-60, are used because they are the most common radioisotopes in LLW and the Cs and Sr are relatively long-lived. Actual conditions at a deepsea disposal site will proba- bly give a leaching index greater than 6 (lower leaching rates), as required for shallow-land burial, for the fol- lowing reasons: 2.2.8 Criterion: Specification: Discussion: Temperatures typical of deep seawater (1 to 4 °C) will reduce leaching by about 30 percent, relative to tests at 20 °C [32], because most solubilities and diffusion rates are reduced with lower temperature. At the tune of container failure only a limited surface area will be exposed to leaching, the remainder will be occluded by the container. Higher concentrations of certain elements in seawater will reduce the rate of release of similar ions from the waste form and, in general, reduce leachability [33]. Paniculate wastes should be rendered nondispersible. Paniculate wastes, such as ashes, powders and other dispersible materials should be immobilized by a suit- able solidification agent to form a homogeneous, mono- lithic, free standing solid. Paniculate wastes are readily dispersible in air and water and are especially hazardous when present as an airborne material of respirable size. To eliminate this hazard, in the event of a container failure during trans- portation, handling and disposal, wastes of this type should be immobilized. Also, a monolithic waste form provides support for the container under the high hydro- static pressures of the disposal environment. Solidifica- tion agents and techniques suitable for wet wastes are 10 ------- 2.2.9 Criterion: Specification: Discussion: 2.2.10 Criterion: Specification: Discussion: generally suitable for paniculate wastes as long as spe- cial consideration is given to handling the waste prior to solidification [21-24]. Free radioactive gaseous wastes should be prohibited from ocean disposal. No radioactive gaseous wastes should be accepted for ocean disposal unless they have been immobilized into stable waste forms such that the pressure in the waste package does not exceed atmospheric pressure. Compressed gases, by their nature, present a hazard to operating personnel during shipboard handling and dis- posal operations. In addition, the possibility of failure resulting from hydrostatic pressures encountered during descent could result in an instantaneous release of gas- eous radioactivity. The disposal of gaseous wastes such as Kr-85 and H-3, will require immobilization by meth- ods such as ion implantation on metal surfaces, sorption on various substrates, or reaction with transition metals to form metal hydrides. Mixed wastes, which contain hazardous constituents, should not be disposed of at a LLW ocean disposal site. Wastes that contain constituents prohibited, as other than contaminants in 40 CFR, Subchapter H, Subpart B, part 227.6 should not be disposed of at a LLW ocean disposal site. The design life time of a container for ocean disposal of LLW is recommended as 200 years in these criteria to ensure segregation of radionuclides from the environ- ment at reasonable cost. This is possible only because radioactive decay significantly reduces the quantity and hazard of these materials during the container lifetime. Many nonradioactive chemically hazardous wastes do not degrade with time or do so very slowly, therefore, any reasonable design objective for container lifetime is inadequate for these materials. 11 ------- 2.2.11 Criterion: Specification: Discussion: The waste should be physically and chemically compat- ible with the solidification agent. Waste forms should retain their structural stability after immersion in seawater for 180 days. Waste form degradation (swelling, cracking and disinte- gration) has been observed when certain chemically incompatible waste/solidification agent combinations have been immersed in water for prolonged times [35, 36, 37]. Swelling and exfoliation of waste forms is a common mode of failure when water is absorbed and waste components expand as they hydrate. Extensive container failure resulting from pressure exerted by the expanding waste could result from a minor leak allow- ing seawater to contact the waste form. After the 200- year container life time, the waste form is expected to maintain its structural stability to minimize radionuclide leaching. Materials that are pyrophoric or explosive should be ex- cluded from the waste form because they are intrinsi- cally incompatible with solidification agents or the tech- niques used to process the waste. Moreover, the hazard posed by these materials during processing, transporta- tion and disposal is unacceptable and, in many circum- stances, is prohibited by transportation regulations. 12 ------- REFERENCES 1. Council on Environmental Quality. October 1970. Ocean Dumping a National PoHcy, A Report to the President prepared by the Council on Environmental Quality, Washington, DC: U.S. Government Printing Office, 2. National Academy of Sciences. 1962. Disposal of Low-Level Radioactive Waste into Pacific Coastal Waters, National Research Council Publication No. 985. Washington, DC: National Academy of Sciences 3. 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"A Survey of Agents and Techniques Applicable to the Solidification of Low-Level Radioactive Wastes," BNL- 51521. Upton, NY: Brookhaven National Laboratory. 25. Holcomb, W.F. 1978. "A Survey of the Available Methods of Solidification for Radioactive Wastes," ORP/TAD-78-2. Washington, DC: U.S. Environmental Protec- tion Agency. 26. Fuhrmann, M. and Colombo, P. 1985. "Evaluation of Solidification Agents for Ocean Disposal of Low-Level Radioactive Waste," draft submitted to U.S. Environmental Protection Agency. Upton, NY: Brookhaven National Laboratory. 27. U.S. Nuclear Regulatory Commission. 1982. Final Environmental Impact Statement on 10 CFR Part 61, "Licensing Requirements for Land Disposal of Radioactive Wastes," NUREG-0945. Washington, DC: U.S. Nuclear Regulatory Commission. 28. Japan Atomic Energy Commission. 1978. Technical Criteria for Storage and Disposal of Radioactive Waste. Tokyo, Japan. 29. Nuclear Energy Agency. 1979. Guidelines for Sea Dumping Packages of Radioactive Waste. Paris, France: Organization for Economic Co-operation and Development. 30. American Nuclear Society. "Measurement of the Leachability of Solidified Low- Level Radioactive Wastes," Final Draft of a Standard. ANS Working Group ANS 16.1. Feb. 1984. 31. Nuclear Regulatory Commission. 1983. Branch Technical Position on Waste Form. Washington, DC: Nuclear Regulatory Commission. 32. Laske, D., Mueller A. and Kuenzle, M. 1985. "Leaching of Cemented Medium-Active Radwaste by Sea Water," Swiss Federal Institute for Reactor Research, Abstract only, In Waste Manegement Research, Abstract No. 16, IAEA/WMRA/16. Vienna: Interna- tional Atomic Energy Agency. 33. Colombo, P. 1983. "Leaching Properties of Solidified TRU Contaminated Incinerator Ash," BNL-33671. Upton, NY: Brookhaven National Laboratory. 34. National Archives and Records Administration. 1984. Code of Federal Regulations, 40 CFR 261.2, Subparts C and D. Washington, DC: US Government Printing Office. 35. Colombo, P. and Neilson, R.M. Jr. 1979. "Properties of Radioactive Wastes and Waste Containers," First Topical Report, BNL-NUREG-50957. Upton, NY: Brookhaven National Laboratory. 36. Zhou, H. and Colombo, P. "Solidification of Radioactive Waste in Masonry Cement," BNL-34788. Paper presented at the Fall Convention of the American Concrete Institute, October 28-November 2, 1984, New York, NY. 15 ------- 37. Colombo, P., Kalb P.D, and Fuhrmann, M. 1983. "Waste Form Development Program Annual Report," October 1982-Septernber 1983, BNL-51756. Upton, NY: Brookhaven National Laboratory. 16 ------- APPENDIX A. LOW-LEVEL RADIOACTIVE WASTES (LLW). To understand the concerns associated with the ocean disposal of low-level radioactive waste and to develop waste package performance criteria and specifications, you will find it useful to consider the types of wastes that comprise low-level radioactive wastes. This appendix will provide information concerning the sources and types of low-level wastes, their physical and chemical properties, and current and projected generation rates. The isotopes normally present in LLW are discussed in terms of their longevity, toxicity, and relative abundance. A-l Definitions Low-level radioactive waste (LLW) is defined fby the Low-Level Radioactive Waste Policy Act (PL 96-573 as amended by PL 99-240) as: radioactive waste not classified as high-level radioactive waste, transuranic waste, spent nuclear fuel or byproduct material as defined in Section lle.(2) of the Atomic Energy Act of 1954; and the Nuclear Regulatory Commission, consistent with existing law. The Act defines by-piroduct maierial as "the tailings or wastes produced by the extraction or concentration of uranium or thorium from any ore processed primarily for its source material content." High-level radioactive waste (HLW) is defined in the Marine Protection, Research and Sanctuaries Act of 1972 (Public Law 92-532) and EPA Ocean Dumping Regulations (40 CFR 227) as "the aqueous waste resulting from the operation of the first cycle solvent extraction system, or equivalent, and the concentrated waste from subsequent extraction cycles, or equivalent, in a facility for reprocessing irradiated reactor fuels or irradiated fuel from nuclear power reactors." This law and its implementing regulations also prohibit the ocean disposal of high-level wastes. Spent nuclear fuel is defined by 40 CFR Part 191.02 (g) (Sept. 19, 1985) entitled, "Environmental Standards for the Management and Disposal of Spent Nuclear Fuel, High- Level and Transuranic Radioactive Wastes; Final Rule." In this rule, spent nuclear fuel is defined as "fuel that has been withdrawn from a nuclear reactor following irradiation, die constituent elements of which have not been separated by reprocessing." The Atomic Energy Commission defined transuranic waste as material excluding high-level waste which contains more than 10 nanocuries per gram of transuranic nuclides, with the exception of Pu-238 and Pu-241, but including U-233 and its daughter products (AEC Manual, Chapter 0511, 1973). The AEC Manual also mentioned that the value of 10 nCi/g is subject to modification based on long-term studies of nuclide migration in soil. On September 14, 1974, the AEC proposed the 10 nCi/g value in the Federal Register. The definition for transuranic (TRU) contaminated material was redefined on September 30, 1982, through DOE ORDER 5820.1, to read; "without regard to source or form, materials that at the end of institutional control periods are contaminated with alpha-emitting radionuclides of atomic number greater than 92 and half-lives greater than 20 years in concentrations greater than 100 nCi/g." This definition does not explicitly apply to commercially generated (NRC licensed) wastes. The NRC limits for land disposal of low- level radioactive wastes (10 CFR 61) include a 100 nCi/g limit for alpha emitting A-l ------- transuianic nuclides with half-life greater than five years, with the exception of Pu-241 and Cm-242, in which case the limits are 3,500 nCi/g and 20,000 nCi/g, respectively. A-2 Sources and Types of Low-Level Wastes LLW are produced as a consequence of both federal government and commercial operations. The majority of federal LLW are from defense related activities, including fuel fabri- cation, reactor operation, spent fuel storage, fuel reprocessing and associated chemical processing operations. (Although fuel reprocessing is primarily associated with the genera- tion of high-level waste, significant quantities of low-level waste are also produced.) In addition, the federal government also generates LLW during facility decontamination and decommissioning activities and from research and development activities. LLW result from both fuel-cycle and nonfuel-cycle operations. Fuel-cycle operations include uranium mining, uranium milling, uranium hexafluoride (UF6) production, uranium enrichment, fuel fabrication, reactor operations, spent fuel storage and facility decontami- nation and decommissioning, (There is currently no fuel reprocessing conducted by the commercial sector, although this may resume in the future.) Commercial fuel-cycle activi- ties are similar in nature to federal government activities and produce analogous wastes. Nonfuel-cycle wastes are produced from both institutional (including medical institutions and universities) and industrial operations (pharmaceutical and other industries). The types of LLW produced by the various sources are summarized in Table A-l. These wastes may be classified as either dry wastes or wet wastes. Dry wastes are solids and include items such as paper, glass, metal, wood, plastic, rubber and rags. Dry wastes may be further classified as combustible or noncombustible and compactible or noncompactible. Combustible dry wastes may be incinerated to reduce volume. The resultant incinerator residue is highly dispersible and requires solidification prior to disposal. The majority of wet wastes are produced from the cleanup of aqueous processes or waste streams prior to recycle or discharge. The type of waste resulting from these cleanup operations depends upon the process used (filtration, ion exchange, evaporation, centrifu- gation, reverse osmosis, ultrafiltration, flocculation, or sedimentation). Filtration produces filter cartridge and filter sludge wastes. Spent resin, powdered resin sludges and regenerant solution wastes result from ion exchange operations. Evaporation, centrifugation, reverse osmosis, ultrafiltration, flocculation and sedimentation processes generate slurry, sludge and aqueous concentrate wastes. Reverse osmosis and ultrafiltration also produce mem- brane wastes. In addition, wastes resulting from these cleanup operations are often subjected to additional treatment to reduce their volume for disposal. For spent resins and sludges this may include a dewatering operation (settling, centrifugation, or filtration), while volume reduction of aqueous wastes is generally accomplished through some form of evaporation. Some wet wastes are combustible (resins, oils, and organic liquids) and A-2 ------- Table A-l Sources and Types of Low-Level Radioactive Wastes [1] TYPES OF HASTE GENERATED DRY WASTES COMBUSTIBLE NONCOMBUSTIBLE FILTER COMPAC- NOHCOH- COMPAC- NONCOH- CAR- SPENT SOURCES TIBLE PACTIBLE TIBLE PACTIBLE TRIDGES RESiNS GOVERNMENT DEFENSE * * * * 04 Dc * RO 4 Dd COMMERCIAL FUEL CYCLE MINING t MILLING * * UFg PRODUCTION ENRICHMENT FUEL FABRICATION * POWER PLANTS * SPENT FUEL STORAGE 040 *»* * NONFUEL CYCLE MEDICAL * * PHARHACEUTICAL6 , , UNIVERSITIES * * OTHER INDUSTRIES" t t * WET HASTES SLURRIES AQUEOUS SPECIAL OTHER AND CONCEN- AQUEOUS ORGANIC SLUDGES TKATES SOLUTIONS3 OILS LIQUIDS HEMBHANES& B10LOUICAL t * t I § * * t * t * * f * f a. Decontamination, pickling, etching, electropolishing, etc. solutions. b. Membranes from processes such as ultrafiltration (UF) and reverse osmosis (RO). c. Decontamination and decommissioning ( D 4 D) operations. d. Research, development, and demonstration (RO 4 D) programs. e. Data on these wastes are Incomplete and difficult to obtain. ------- incineration could be used to reduce waste volume. More detailed descriptions of these wastes and their origins can be found in the literature [1-4]. Generally, wet wastes are solidified prior to disposal. Exceptions include filter cartridges, some spent ion exchange resins and filter sludges and organic liquids. Solidifi- cation agents commonly used in the United States include portland cements and modified Portland cements. Urea-formaldehyde is no longer used. Thermosetting resins and asphalt are beginning to be used for the solidification of LLW in this country. Sorbents, such as vermiculite and synthetic calcium silicates have been used with wastes to immobilize liquids. While this practice has been greatly reduced at commercial fuel-cycle facilities due to recent NRC regulations (10 CFR 61) [5], their use is still faiily widespread at some government installations and at commercial nonfuel-cycle facilities. A-3 Generation Rates of Low-Level Wastes Estimated volumes and activities of LLW generated in the United States during 1985 are shown in Table A-2. More than half of the volume (61 percent) and activity (58 percent) originated from DOE/Defense sources. These wastes are not broken down further in Table A-2 but they have been categorized as: biological (0.01 volume percent), contaminated equipment (0.94 volume percent), decontamination debris (22 volume per- cent), dry solids (54.4 .volume percent), solidified sludges (0.02 volume percent) and "not classified" (23 volume percent) [6]. Some 60 volume percent of commercial low-level waste is generated in the fuel cycle, primarily by power reactor operations. Reactors generate 67 percent of the activity, most of which (99* percent) is tritium [6]. Considering the mix of power reactor types and their respective liquid processing systems (deep-bed resins or precoat filters for boiling water reactors (BWRs) and conden- sate polishing systems (CPS) or no CPS for pressurized water reactors (PWRs) [2,7]), about 48 percent of power reactor wastes are dry solids. The remaining waste fraction consists primarily of wet wastes which have been solidified prior to disposal. Dry solids constitute approximately 42 percent of institutional wastes [3] and as much as 90 percent of the volume of the LLW generated by some industrial producers [4]. Most of these dry wastes contain relatively small quantities of radionuclides. A significant fraction of this waste may not be contaminated and is referred to as "suspect" waste. Estimates of LLW volumetric generation rates and activities through the year 2020 are listed in Table A-3 [6]. Projections of the volume of fuel-cycle LLW are based upon a proposed reference growth scenario projecting 148 gigawatts (GW) of nuclear generated electricity by the year 2020. The generation .rate of governmental LLW is expected to increase significantly between 1990 and 2000 because of LLW resulting from high-level waste reprocessing as the Savannah River Plant. The generation rate of commercial LLW produced annually is projected to more than double by 2020. These projections do not consider governmental LLW resulting.from the decontamination and decommissioning of formerly utilized or surplused sites under the Formerly Utilized Sites Remedial Action A-4 ------- Program (FUSRAP) or the Surplus Facilities Management Program (SFMP). They also do not consider LLW resulting from a possible resumption of commercial spent fuel reprocess- ing. Most of this increase is due to increased quantities of fuel-cycle waste resulting from the expansion of installed power reactor capacity. The generation rate of fuel-cycle LLW is anticipated to increase by 380 percent between 1980 and 2200, while generation rates for nonfuel-cycle wastes over this period are projected to increase by 180 percent; however, reactor facilities in particular have significant incentive to reduce waste volume because of high transportation and disposal costs, especially following passage of PL 99-240. Table A-2 Estimates of Volumes and Activities of LLW Generated in the Untied States in 1985 [6] Source DOE/Defense Commercial Total Commercial LLW(a) Reactor Operations 43 x 103 51 398 x 103 67 Institutional^ 25 x 103 33 398 x 103 Industrial 5 x 103 7 164 x 103 28 Other(b) 4 x 103 3 30 x 103 __5_ 77 x 103 100 593 x 103 100 (a)Calculated from waste sent to burial site (b)Primarily UF6 (c>This js an anomalously low value. Typical values for recent years are - 1200 x 103 Ci. ( Institutional sources include hospitals, medical schools and universities. Cubic Meters 120 x 103 77 x 103 197 x 103 Volume Percentage 61 39 100 Curies 814 x 103(c) 593 x 103 1407 x 103 Activity Percentage 58 42 100 A-5 ------- Table A-3 Projected Low-Level Waste Generation Rates and Activities, 1985-2020 [6] GOVERNMENT Year 1985 1990 1995 2000 2005 2010 Volume 104 M3/yr 12.0 12.9 12.9 12.9 11.0 11.0 Activity 106 Ci/yr 0.8 1.6 1.6 1.6 1.6 1.6 COMMERCIAL* Volume 104 M3/yr 7.7 8.1 8.8 9.4 10.9 12.5 Activity 106 Ci/yr 0.59 0.81 0.88 0.93 1.11 1.31 2015 2020 11.0 11.0 1.6 1.6 14.0 16.0 1.49 1.73 *Based on a fuel cycle with no reprocessing A-4 Radionuclides Commonly Present in LLW More than 2,000 radionuclides exist in nature or have been produced by nuclear reactions. The vast majority of these are not of concern in waste disposal because their half-lives are much shorter than the time required to collect and process the waste. After a decay time of 7 half-lives, less than 1 percent of the original activity of a given radionuclide remains; after 10 half-lives less than one part in a thousand remains, and after 20 half-lives less than one part in a million of the original activity remains. Thus, radionuclides having half-lives shorter than 0.1 years will have decayed toless than 0.1 percent of their original activity after one year of aging and to less than 0.0001 percent after two years. Most of the radionuclides appearing in LLW are products of nuclear fission or neutron activation of stable elements contained in reactor cores (coolant, fuel hardware and cladding, reactor core structures, control rods, etc.). A few additional radionuclides manufactured by charged particle accelerators appear in industrial and institutional LLW; e.g., Na-22, Cl-36, Cd-109. A-6 ------- The distribution and quantity of specific radionuclides appearing in various low-level waste streams of reactors is quite diverse, depending on the reactor design, degree of fuel bumup and the details of the waste processing equipment. In general, the wastes have been poorly characterized because reliable assays have been limited. Consequently, large inconsistencies appear in published data. Recently, R.E. Wild et al. [8] completed a comprehensive analysis of radwaste data which appears to be particularly thorough. Some additional data have been taken from other sources, as cited in the references. Table A-4 lists the radionuclides commonly found in reactor waste streams. Isotopes with half-lives shorter than 0.5 years have been omitted from the table, since they will have decayed to negligible concentrations within the first five years after packaging, and therefore, do not contribute significantly to the long-term radioactive inventory in the disposal environment. Radionuclides with half-lives in the range of 0,5 to 5 years have been included because they must be considered when handling the wastes during disposal operations. A-5 Quantities of Radionuclides in LLW Column 4 of Table A-4 lists the quantities of each isotope that are estimated to appear in the LLW at commercial nuclear power plants in the year 1984. Most of the inventory of fission products remains trapped in the spent fuel and does not enter the LLW streams. (If reprocessing of spent fuel is resumed, the LLW streams from reprocessing plants will substantially increase the quantities of fission products for LLW disposal, even though most of the inventory will go into high-level waste streams.) Industrial and institutional LLW originate from many sources, including reactors and charged particle accelerators and do not show typical fission product distribution. The most common radionuclides in industrial and institutional LLW, with half-lives greater than 0.5 years are C-14, H-3 and, to a lesser extent, Cs-137 [6]. This inventory omits several important sources of waste; e.g., DOE production and research reactors and the nuclear navy, since such information is not in the public domain. However, as a rough estimate it can be assumed that the inventories will have a distribution similar to that shown in Table A-2 and that the listed inventories would about double. Table A-5 compares the estimated 1985 United States LLW inventory with the IAEA release rate limits. If the United States is to use ocean disposal for LLW at an annual rate equal to the 1985 inventory, only a small fraction of the IAEA release rate limits would be approached. Therefore, it can be concluded that the IAEA release rate limits will not be a major restrictive factor if the United States should decide to resume ocean disposal of LLW. A-7 ------- Element Table A-4 Radioactive Isotopes in Wastes from Commercial Nuclear Power Plants Only those important isotopes with half-lives greater than 0.5 years have been included. The "relative hazard index" (RHI) is defined as the quantity of water (in liters) required to dilute 1 micro-Ci of the radio- nuclide to Maximum Permissable Concentration (MPC) listed in 10 CFR 20, Appendix B, Table II, Column 2, Annual(a) Quantities Radionuclide(a> Half-Life(b) (1984) Relative Hazard Index (RHI)(C) After Various Periods of Radio- active Decay During Confinement Hydrogen Carbon Manganese Iron Nickel Cobalt Nickel Strontium Technetium Iodine Cesium Cesium Uranium Uranium H-3 C-14 Mn-54 Fe-55 Ni-59 Co-60 Ni-63 Sr-90 Tc-99 1-129 Cs-134 Cs-137 U-235 U-238 (Years) 12.33 5730 0.86 2.7 7.5 x 104 5.27 100.1 28.8 2.14 x 105 1.56 x 107 2.06 30.17 7.04 x 10s 4.47 x 109 (Ci/year) 135 18 10 1.9 x 105 180 2.5 x 105 1.8 x 104 120 0.31 0.87 5 x 103 8.4 x 103 0.21 1.6 (liters/initial micro-Ci) 0 yrs 0.33 1.3 0.01 1.3 5 20 33 3333 3.3 17000 11111 50 33 25 110 yrs 0.19 1.3 neg. 0.1 5 5.4 30.8 2620 3.3 17000 384 39.7 33 25 200 yrs neg.(d) 1.27 neg. neg- 5 neg. 8.25 27.1 3.3 17000 neg. 0.5 33 25 300 yrs neg. 1.25 neg. neg. 5 neg. 4.14 2.44 3.3 17000 neg. 0.05 33 25 fn\ Significant radionuclides were identified and quantities estimated from data given in Ref. 8 and 7 and based on 42.3 gigawatts electric-year (GWe-yr) for 1984 [10]. (b)Ref. 9. (c>The RHI entries for 1 Ci at 0 years. Values shown for subsequent years take the radioactive decay into account. (d>Neg. negligible, less than 10"3. A-8 ------- Table A-5 Comparison of the Estimated 1985 United States LLW Inventory With the IAEA Criteria If the United States used ocean disposal at the estimated rate of 1985 gen- eration of wastes, the IAEA guidelines would not be exceeded. Grout Alpha emitters Beta/gamma emitters with half-lives of at least 1.0 years (excluding tritium) Tritium and beta/gamma emitters with half- lives less than 1.0 years Release Rate Limit 5.4 x 108 (2 x 107TBq) 8.1 x 109 (3 x Estimated 1985 U.S. (Ci/yr) [11] IAEA Single-Site 1.35 x 106 (5 x lO^Bq) LLW Inventory^ [6] (Ci/yr) 4.1 x 103 (152TBq) Fraction US/ IAEA 3 x 10° 2.8 x 10 (1.04 x 2.4 x (8.93 x 103TBq) 5.2 x 10" 3.0 x 10 -5 (a) Allowance for defense LLW would approximately double the numbers in this col- umn. A-9 ------- A-6 Toxicity of Radionuciides The radioactivity of a sample, measured in units of curies, is not an accurate reflection of its toxicity. (Of coarse, for a given isotope, 2 curies is twice as toxic as 1 curie.) The toxicity of a radionuclide depends also on the type and energy of the radiation it emits (alpha particles, beta particles, gamma rays, x-rays) and on the biochemical behavior of the chemical compounds of the radionuclide. The latter determines the routes by which a radionuclide can enter a living organism, which organs will be affected and the average residence time in each of the organs. The toxicity of individual radionuclides has been the continuing subject of investiga- tion by the International Commission on Radiological Protection (ICRP), the National Council on Radiation Protection and Measurement (NCRP) and various other national and international bodies. The recommendations of these organizations have been adopted with a slight modification by the U.S. Nuclear Regulatory Commission (NRC). The maximum permissible concentration (MPC) for each radionuclides in air and water is listed in 10 CFR 20, Appendix B [12]. The inverse of the MPC values can be regarded as a measure of the toxicity of each radionuclide and is referred to as the "relative hazard index," were RHI I/ (MPC x 10"3). Columns 5-8 of Table A-4 list the decreasing value of RHI selected for 0, 10, 200 and 300 years of containment. RHI is selected to illustrate the relative reduction in toxicity for radionuclides of importance in LLW. A-7 Identification of Most Important Radionuclides The data in Table A-4 make it possible to identify the most important isotopes from the viewpoint of disposal. These are the isotopes that have long half-lives, higher toxicities and are produced in large quantities. The three radionuclides that dominate disposal considerations for typical waste streams are: Sr-90, Cs-137 and Co-60. The radionuclides in LLW can be divided into two major groups: (1) those with half- lives of 30 years or less, and (2) those with half-lives greater than 30 years. The rationale for this division is that practical engineered barriers can be designed to immobilize the radionuclides with half-lives less than 30 years for the duration of their significant toxicity. For radionuclides with half-lives greater than 30 years factors other than engineered barriers, i.e., natural barriers, must be relied upon for long-term radiation protection. Except in unusual circumstances; e.g., cases in which radiochemical separations have been performed on wastes prior to disposal, relatively few radionuclides (Sr-90, Cs-137, Co-60) will dominate the waste stream and will determine the performance specifications of the waste package. Packages that can immobilize these radionuclides can adequately retain radionuclides with shorter half-lives. It is prudent to assume that after several hundred years economically practical waste packages on the ocean floor will have gradually deteriorated and the residual radioactivity will have been discharged into the surrounding environment. The consequences of the ultimate releases must be examined in geochemical terms. These include: A-10 ------- concentrations of identical or similar i^dionuclides already present in ocean waters from natural sources; abundance of stable isotopes of the element relative to the inventory of radioisotope released; chemical and geochemical behavior of the radionuclides in the disposal environ- ment. A-8 Conclusions The radionuclide content and quantities of radioactivity in low-level waste at current annual generation rates in the United States could be accommodated by ocean disposal without exceeding the limits recommended by the IAEA. Engineered barriers combined with natural barriers would enhance the margin of safety by retaining most of the shorter lived radionuclides for the duration of their toxicity. The desirable time span of 200 years for the integrity of the outer container barriers is dictated primarily by the radionuclides, Sr-90 and Cs-137, because of their relative quantities and their half-lives of approximately 30 years. A-ll ------- APPENDIX A. REFERENCES 1. Kibbey, A.H. and Godbee, H.W. 1980. A State-of-the-Art-Report on Low-Level Radioactive Waste Treatment, ORNL/TM-7427. Oak Ridge, TN: Oak Ridge National Laboratory. 2. Phillips, J., et al. 1979. Waste Inventory Report for Reactor and Fuel Fabrication Facility Wastes. ONWI-20/NUS-3314. Rockville, MD: NUS Corporation. 3. Beck, T.J., Cooley L.R. and McCampbell, M.R. 1979. Institutional Radioactive Wastes-1977, NUREG/CF-1137. Baltimore, MD: University of Maryland. 4. General Research Corporation. 1980. Study of Chemical Toxicity of Low-Level Wastes. NUREG/CR-1973. Santa Barbara, CA: General Research Corporation. 5. Nuclear Regulatory Commission. May 1983. Branch Technical Position on Waste Form. Washington, DC: U.S. Nuclear Regulatory Commission. 6. U.S. Department of Energy. 1986. Integrated Data Base for 1986: Spent Fuel and Radioactive Waste Inventories, Projections and Characteristics, DOE/RW-0006, Rev. 2. Washington, DC: U.S. Department of Energy. 7. Mullarkey, T.B. et al. 1976. A Survey and Evaluation of Handling and Disposing of Solid Low-Level Nuclear Fuel Cycle Wastes, AIF/NESP-008. Rockville, MD: NUS Corporation. 8. Wild, R.E. et al. 1981. Data Base for Radioactive Waste Management. Waste Source Options Report, NUREG/CR-1759, Volume 2. Dames and Moore, Inc. 9. Lederer, C.M. and Shirely, V.S. editors. 1978. Table of Isotopes, 7 Edition. New York: John Wiley and Sons, Inc. 10. Office of Resource Management. 1985. Licensed Operating Reactors Status Summary Report, Data as of 12-31-84. NUREG-0020, Vol. 9, No. 1. Washington, DC: U.S. Nuclear Regulatory Commission. 11. International Atomic Energy Agency, Report of Intersessional Activities Relating to the Disposal of Radioactive Wastes at Sea, including the Final Draft of the Scientific Review: Revision of the Definition Required by Annex I (paragraph 6) to the Convention and of the Recommendation Required by Annex n (Section D), LDC 9/INF.14, GOV/2218/Add.l, IAEA, Vienna, Austria, September 1985. 12. National Archives and Records Administration. Jan. 9, 1986. Code of Federal Regula- tions, 10 CFR 20, Appendix B, Table II, Column 2. Washington, DC: U.S. Govern- ment Printing Office. A-12 ------- APPENDIX B, DOMESTIC AND INTERNATIONAL REGULATIONS WHICH POTENTIALLY IMPACT THE OCEAN DISPOSAL OF LOW-LEVEL WASTES A review of domestic and international regulations concerning the ocean disposal of low-level radioactive wastes is presented. These regulations potentially impact the develop- ment of waste package performance criteria, and therefore, must be considered. B-l United States B-l.l Environmental Protection Agency (EPA) The Environmental Protection Agency was created under Reorganization Plan Number 3 of 1970 to consolidate in one agency various Federal pollution abatement activities which had been performed under separate organizations. EPA regulations are published as Title 40 of the Code of Federal Regulations. The EPA has the authority to control the ocean disposal of all wastes, including radioactive wastes as specified in the Marine Protection, Research and Sanctuaries Act of 1972. The Marine Protection, Research and Sanctuaries Act of 1972 (Public Law 92-532) promotes a national policy to regulate the dumping into ocean waters of all materials which would adversely affect human health and welfare or the marine environment, ecological systems or economic potential. The Act prohibits the dumping or transportation for the purpose of dumping any radiological, chemical or biological warfare agent or any high- level radioactive waste into the territorial ocean waters of the United States (defined as 12 nautical miles from U.S. territory). It also describes conditions whereby permit' "nay be issued by EPA for ocean disposal of materials not otherwise prohibited. This Act was amended in 1974 (Public Law 93-254) to implement the provisions of the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter (London Dumping Convention), and for other purposes. In January 1977, EPA published regulations concerning the transportation aisi dump- ing of wastes in the ocean (40 CFR 220-229) [1]. These regulations contain general requirements for all wastes. They also establish a policy of isolation and containment for radioactive waste through two specific criteria: (1) Radioactive materials must be contained to prevent their direct dispersion or dilution in ocean waters. (2) The materials to be disposed of must decay, decompose, or radiodecay to environ- mentally innocuous materials within the life expectancy of the containers and/or their inert matrix. In December, 1982, the Ocean Dumping Act was further amended by PL 97-424 to provide for a Radioactive Material Disposal Impact Assessment which includes a specific B-l ------- consideration of structural aspects of each radioactive waste container when evaluating any permit for disposal. EPA has also promulgated regulations for determining if wastes are hazardous for purposes of implementing the Solid Waste Disposal Act as amended by the Resource Conservation and Recovery Act of 1976 (RCRA). The requirements for "Identification and Listing of Hazardous Waste" are contained in 40 CFR 261. The applicability of RCRA standards to mixed wastes (hazardous and radioactive) as they are generated at defense and commercially operated nuclear facilities and the potential impact on current waste disposal is of major concern to both the U.S. Department of Energy (DOE) and the U.S. Nuclear Regulatory Commission (NRC). B-1.2 Nuclear Regulatory Commission (NRC) The development of commercial nuclear activities has been subject to regulation since 1954. At that time, the Atomic Energy Act of 1954 created the authority to regulate the development of a civilian nuclear power program. The regulatory functions were performed by the Atomic Energy Commission and are currently the responsibility of the Nuclear Regulatory Commission, which was created by the Energy Reorganization Act of 1974. The basic authorities derived from the Atomic Energy Act include licensing and regulating the production, use, ownership and distribution of special nuclear materials, source material and by-product materials, as well as licensing and control over the manufacture, produc- tion, possession, use, importation or exportation of production and utilization facilities. Nuclear Regulatory Commission regulations are issued under Title 10 of the Code of Federal Regulations. Radioactive waste disposal regulations are primarily found in 10 CFF. Part 20 - Standards for Protection Against Radiation. In particular, it requires NRC authorization for ocean disposal of wastes from NRC-licensed facilities. Ocean disposal also requires a permit from the Environment?! Protection Agency under the Marine Protection, Research and Sanctuaries Act of 1972 for all nonprohibited radioactive wastes, and for all potential disposers. Nuclear Regulatory Commission regulations pertaining to radioactive waste form stability for land disposal is addressed in 10 CFR 61.56(b) [2]. These requirements are "intended to ensure that the waste does not structurally degrade and affect overall stability of the site through slumping, collapse, or other failure of the disposal unit and thereby, lead to water infiltration." Elaboration of this requirement is made in the Nuclear Regulatory Commission Branch Technical Position on the Waste Form (May 1983) [3] which provides guidance on waste form test methods and results acceptable for demonstrating compliance with 10 CFR 61 waste stability criteria. B-2 ------- B-1.3 Department of Transportation (DOT) The Department of Transportation was established by Congress (PL 89-670) in 1967 to administer and coordinate Federal government transportation programs. The Department of Transportation is authorized to regulate the transportation of explosives and other danger- ous, articles, including radioactive materials, in interstate and foreign commerce. Under the terms of a memorandum of understanding between the DOT and the NRC, the Department of Transportation has primary responsibility for regulations concerning the transportation of NRC-liceased materials, except for shipments of intermediate and large quantities of radioactive materials and shipments of fissile materials, which are primarily under NRC's jurisdiction. The DOT's primary responsibility is to develop safety standards for the classification and labelling of all packages of radioactive material and regulation of carriers and freight forwarding operations. The Department of Transportation regulations governing transportation of radioactive materials are largely found in Title 49, Parts 170-179 of the Code of Federal Regulations. B-2 International B-2.1 The Nuclear Energy Agency of the Organization for Economic Cooperation and Development (NEA/OECD) The OECD Nuclear Energy Agency (NEA) was established in 1972, replacing OECD's European Nuclear Energy Agency (ENEA). NEA now includes all the European Member Countries of OECD as well as Australia, Canada, Japan and the United States (23 countries). NEA's responsibilites regarding ocean disposal of low-level waste lie with the Mem- ber Countries of OECD and, recently, fall under a Decision of the OECD Council establishing a Multilateral Consultation and Surveillance Mechanism for Sea Dumping of Radioactive Waste (the OECD Council Decision) [4]. Twenty-one of the 23 member countries, excluding Austria and Australia, are Participating Countries to the OECD Council Decision. This mechanism is designed to further the objectives of the London Dumping Convenr.on. It provides for the establishment and review of standards, guidelines and procedures for the safe disposal of radioactive wastes, taking into account the provisions of the London Dumping Convention of 1972 and the IAEA Definition and Recommendations of 1978. In October 1978, the NEA guidelines were revised to conform to the requirements of the London Convention and the IAEA Recommendations. This revision was published in April 1979 [5]. B-2.2 The London Dumping Convention The Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter, commonly referred to as the London Dumping Convention, was adopted by B-3 ------- an intergovernmental conference in London in November 1972. The London Dumping Convention is an international convention to control marine pollution from the dumping of waste, including the dumping of radioactive material, in international waters. It applies only to those countries, including the United States, who have ratified, acceded or succeeded to the Convention (over 60 countries as of January 1986). The International Maritime Consultative Organization (IMCO) was designated as the formal secretariat for the Convention during a meeting of the parties in December 1975. B-2.3 International Atomic Energy Agency (IAEA) The London Dumping Convention provides for the IAEA (as the competent interna- tional body) to define "high-level radioactive wastes or other high-level radioactive matter as unsuitable for dumping at sea" [6]. The IAEA also is entrusted with the responsibility of establishing recommendations that the Contracting Parties to the Convention should con- sider in issuing permits for the dumping at sea of radioactive wastes or other radioactive material not otherwise prohibited by the IAEA Definition. Consequently, IAEA responsi- bilities for recommendations and guidance on the dumping of radioactive waste at sea comes from the London Dumping Convention with the recommendation." and guidance being taken into account by the Contracting Parties to the Convention. Such recommenda- tions and guidance were issued by IAEA in 1978 [7], and revised in 1985 [8]. For example, high-level radioactive waste is defined and limits placed on annual dumping rates of three classes of radionuclides. Criteria are also given for low-level radioactive waste forms and for approval of the ship and equipment used for ocean disposal. B-4 ------- APPENDIX B. REFERENCE 1. National Archives and Records Administration. 1982. Code of Federal Regulations, 40 CFR 220-229. Washington, DC: U.S. Government Printing Office. 2. National Archives and Records Administration. 1982. Code of Federal Regulations, 10 CFR 61. Washington, DC: U.S. Government Printing Office. 3. Nuclear Regulatory Commission. 1983. Branch Technical Position on Waste Form. Washington DC: Nuclear Regulatory Commission. 4. Nuclear Energy Agency. 1978. Decision of the OECD Counil of 22 July 1977 Establishing a Multilateral Consultation and Surveillance Mechanism for Sea Dump- ing of Radioactive Waste," NEA Sixth Activity Report 1977. Paris, France: Organiza- tion for Economic Cooperation Development. 5. Nuclear Energy Agency. 1979. Guidelines for Sea Dumping of Radioactive Waste, Revised Version. Paris, France: Organization for Economic Cooperation and Devel- opment. 6. "Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter," drawn up at the Intergovernmental Conference on the Dumping of Wastes at Sea, held in London, 30 October-10 November, 1972. 7. International Atomic Energy Agency, "Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter, - The Definition Required by Annex I, paragraph 6 to the Convention, and the Recommendations Required by Annex H, Section D," INFCIRC/205/Add.l/Rev. 1, IAEA, Vienna, Austria, August 1978. 8. -International Atomic Energy Agency, Report of Intersessional Activities Relating to the Disposal of Radioactive Wastes at Sea, including the Final Draft of the Scientific Review: Revision of the Definition Required by Annex I (paragraph 6) to the Convention and of the Recommendation Required by Annex n (Section D), LDC 9/INF.14, GOV/2218/Add.l, IAEA, Vienna, Austria, September 1985. B-5 ------- APPENDIX C. GLOSSARY Some of the terminology used in this report is defined to provide the reader with a quick reference to uncommon terms, or terms having unique meanings in the field of radioactive waste management. Although it is acknowledged that the definitions may not be universally accepted, it is anticipated that the inclusion of this glossary will result in a better understanding of the criteria in Section 2. Acceptable Limit: Activity: Alpha Particle: As Low As Reasonably Achievable (ALARA) Barrier: Becquerel (Bq): Beta Particle: Buoyant Material: Radioactivity or radiation limit acceptable to a regulatory body. A measure of the rate of radioactive decay occurring in a given quantity of material; i.e., the number of nuclear disintegrations per unit of time. Activity is commonly expressed in curies (Ci), or becquerel (Bq). A positively charged nuclear particle consisting of two protons and two neutrons. Alpha particles are ejected during certain radioactive tranformations usually involv- ing very heavy isotopes; i.e., those of Z > 82. ALARA refers to limiting release and exposure and is used by the Nuclear Regulatory Commission (NRC) (10 CFR 50.34) in the context of " as low as reasonably achievable, taking into account the state of technology and the economics of improvements in relation to benefits to the public health and safety and other societal and socio- economic considerations." Any medium, engineered or natural, which prevents or retards the movement of radioactive materials. A unit of radioactivity equivalent to 1 disintegration/ second or approximately 2.7 x 10~u Ci. A positively or negatively charged subatomic particle hav- ing an atomic mass of 5.4 x 10" (1 emitted from an atomic nucleus during certain radioactive transformations. Material having the tendency or capacity to remain afloat when Immersed in water. C-l ------- Compressive Strength: Container: Container Lifetime: Containment: Criterion: Curie (Ci): Deepsea: Dispersion: Disposal: Dumping: (also Ocean Dumping) Environment: Fuel Cycle: Fuel Reprocessing: The load per unit of cross-sectional area under which a solid block fails. The receptacle into which a waste form is placed for disposal. The time period during which the container effectively serves as a barrier to radionuclide movement. The retention of radioactive material by the use of suitable packaging in such a way that it is effectively prevented from being dispersed into the environment. A standard on which a decision or judgement may be based. It may be qualitative or quantitative. A unit of activity equal to 3.7 x 10 disintegrations per second. In context of ocean disposal of radioactive wastes, it is that part of the ocean where the average water depth is -greater than 4,000 meters. The summed effect of those processes of transport, diffu- sion and mixing which tend to distribute materials from wastes or effluents through an increasing volume of water. The ultimate effect appears as a dilution of material. The disposition of waste materials at a designated site without the intention of routine retrieval. The deliberate disposal of wastes into the ocean from vessels, aircraft, platforms or other manmade structures, as defined by the Marine Protection, Research and Sanctu- aries Act of 1972, as amended. The sum of all the conditions and influences that affect the survival and development of an organism. All the steps involved in supplying and using fuel materi- als for nuclear reactors, including waste management op- erations. The dissolving of spent fuel elements for the removal of waste materials and the recovery and segregation of reus- able materials. C-2 ------- Gamma Ray: Gigawatt (GW): Gigawatts electric-year (GWe-yr): Half-life: Hazard: High-Level Waste (HLW): Immobilization: Isolation: Isotope: High-energy, short-wavelength, electromagnetic radiation deriving from nuclear transformations; similar to, but gen- erally more penetrating than x-rays. Gamma radiation frequently accompanies alpha and beta emissions and al- ways accompanies fission. A rate of doing work or expending energy. A gigawatt is equivalent to 10 watts or 109 joules per second. A unit of energy or work used to measure large-scale electricity production. It is equivalent to approximately 3.2 x 1016 joules. The characteristic time in which half the atoms of a particular radioactive substance disintegrate. Each radio- nuclide has a unique half-life. A natural or manmade cause of a potential deleterious effect, as differentiated from an expected or actual delete- rious effect. Irradiated reactor fuel; liquid wastes from the first solvent extraction cycle of chemical reprocessing of irradiated reactor fuel, or equivalent processes; and solidified forms of such waste; and and other waste or matter of activity concentration exceed- ing: (a) 5 x 10"5 TBq-kg"1 for alpha emitters; (b) 2 x 10"2 TBq-kg"1 for beta/gamma emitters with half- lives of greater than one year (excluding tritium); and (c) 3 TBq-kg" for tritium and beta/gamma emitters with half-lives of one year or less. The above activity concentrations shall be averaged over a gross mass not exceeding 1,000 tonnes. Conversion of a waste to a form that reduces the potential for migration or dispersion of radionuclides during stor- age, transportation and disposal. The segregation of radionuclides from the human environ- ment and the restriction of their release into the environ- ment in unacceptable quantities or concentrations. Atoms of the same atomic number but with different atomic masses. For a given element the chemical properties of its various isotopes are almost identical; however, the nuclear properties of each isotope are distinctly different. C-3 ------- Leach Rate: Low-Level Waste (LLW): Matrix Material: Maximum Permissible Concentration (MFC): Migration (radionuclide): Mixed Waste: Monolith: Multibarrier: Nuclide: Neutron: Package: Pyrophoric Material: Radioactive Decay: The rate of release of components from a solid in the presence of an aqueous environment. Radioactive waste not classified as either high-level radio- active waste, transuranic waste, spent nuclear fuel or ura- nium mill tailings, as defined in the Low-level Radioac- tive Waste Policy Act (PL 96-573). See Solidification Agent. Maximum levels of radioactivity in drinking water or in air for the occupational worker, as defined in 10 CFR 20, Appendix B. The movement of radionuclides through various media due to dissolution, fluid flow and/or by diffusion. Radioactive wastes that contain nonradioactive co- contaminants (defined as hazardous in 40 CFR 261). Exhibiting rigid and uniform properties. A system using two or more independent barriers to iso- late the waste from the human environment. These can include the waste form, the container, other engineered barriers and the disposal medium and its environment. A species of the nucleus of an atom characterized by its mass number, atomic number and nuclear energy state. An uncharged nuclear particle, with atomic mass of ap- proximately 1, which is emitted from an atomic nucleus during certain radioactive transformations. The waste form and any container(s) as it is prepared for handling, transport, storage and disposal. Any material (solid or liquid) that ignites spontaneously in dry or moist air at or below 130°F. A spontaneous nuclear transformation in which alpha par- ticles, beta particles or neutrons are emitted, sometimes with associated gamma rays, or x-ray radiation is emitted following orbital electron capture, or the nucleus undergoes spontaneous fission. C-4 ------- Radioactive Waste: (Radwaste) Relative Hazard Index (Rffl): Site (Disposal or Dump): Solidification: Solidification Agent: Spent Nuclear Fuel: Transuranic Waste (TRU): Uranium Mill Tailings: Waste Form: Waste Management: X-ray: Any material or equipment that contains or is contami- nated with radionuclides at concentrations or radioactivity levels established by the regulatory authorities and, for which there is no anticipated use. The quantity of water (in liters) required to dilute 1 j^Ci of an isotope to MFC, listed in 10 CFR 20, Appendix B. The area containing low-level nuclear waste that is de- fined by a boundary and which is under effective control of the implementing organization. Conversion of liquid radioactive waste to a dry, stable monolithic solid. A material used to solidify or immobilize radioactive waste by forming a monolithic solid (e.g, cement, bitu- men, polymer). Nuclear fuel which has been discharged from a reactor after having been subjected to nuclear reactions. (Fuel is usually discharged because it has been consumed to the design limit or because of failure or for necessary reactor maintenance). Wastes containing quantities of alpha-emitting radionu- clides of atomic number greater than 92 in concentrations greater than 100 nCi/g. Finely ground residues resulting from processing of ores for recovery of uranium. A monolithic free standing solid resulting from the incor- poration of waste into a matrix material (e.g., liquid in concrete, solids in bitumen). The planning and execution of essential functions relating to radioactive wastes, including treatment, packaging, in- terim storage, transportation and disposal. A penetrating form of electromagnetic radiation emitted either when the inner orbital electrons of an excited atom return to their normal state (characteristic x-rays), or when a metal target is bombarded with high-speed electrons. C-5 f US. QQVEftBEi!£«T PfUHTENCl OFFICB: >SH ~ 617-003 - l ------- |