Exempt Radioactive Waste

4 Exempt Radioactive Wastes. The radioactive waste classification system in the United States does not include a general class of exempt waste (see Table 1.1). Rather, many products and materials that contain small amounts of radionuclides (e.g., specified consumer products, liquid scintillation counters containing 3H and 14C) have been exempted from requirements for use or disposal as radioactive material on a case-by-case basis. The various exemption levels are intended to correspond to low doses to the public, especially compared with dose limits in radiation protection standards for the public or doses due to natural background radiation. However, the exemption levels are not based on a particular dose, and potential doses to the public resulting from use or disposal of the exempt products and materials vary widely. 

A general class of exempt radioactive waste would include any waste containing sufficiently small amounts of radionuclides that the materials could be managed and disposed of as if they were nonradioactive and still provide adequate protection of human health. An important benefit of establishing a general class of exempt radioactive waste would be a reduction in the resources required for waste treatment and disposal. Classification of waste as exempt also would allow consideration of beneficial uses of the materials. 

5 Deficiencies in the Radioactive Waste Classification System. The classification system for radioactive waste in the United States summarized in Table 1.1 is based primarily on the earliest descriptions of different classes of waste that arises from chemical reprocessing of spent nuclear fuel and subsequent processing of nuclear materials that were developed beginning in the late 1950s. These wastes were considered to be the most important in regard to potential radiological impacts on workers. 

As summarized below, however, the classification system that encompasses nuclear fuel-cycle and NARM waste also has exhibited a number of deficiencies that call into question its continued suitability. 

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Legal impediments to development of a new waste classification system would be ignored. These include, for example, the distinction between radioactive waste that arises from operations of the nuclear fuel-cycle and NARM waste, which is based on provisions of AEA, the distinction between radioactive and hazardous chemical wastes, which is based on provisions of AEA and RCRA, and the provision in the National Energy Policy Act that prohibits NRC from establishing a general class of exempt radioactive waste. 

IAEA has been developing recommendations on classification of radioactive waste and principles for exempting radioactive waste from regulatory requirements for radioactive material for more than 30 y. This Section briefly reviews these developments. 

Exempt waste would be defined as waste that contains such low concentrations of radionuclides that it could be exempted from regulatory control as radioactive material because the radiological hazards associated with disposal of the waste would be negligible. The basis for defining exempt radioactive waste recommended by IAEA is a limit on annual dose to individuals from waste disposal of 10 xSv (see Section 4.1.3.2). 

Finally, recommendations on principles that could be used to exempt radioactive waste from regulatory control as radioactive material have been developed both in the United States (NCRP,... 

The provision of the National Energy Policy Act (NEPA, 1992) that prohibits NRC from establishing dose criteria that could be used to exempt radioactive wastes from licensing requirements for disposal clearly is an impediment to development of generally applicable exemption levels for radioactive waste. An exempt class of radioactive and hazardous chemical waste is the cornerstone of the risk-based waste classification system developed in this Report, and any legal and regulatory impediments to establishment of generally applicable exemption levels would need to be removed. 

On July 18, 2000, the Agency released HWIR-waste exemption levels for 36 chemicals that were developed using a risk model known as the Multimedia, Multi-pathway and Multi-receptor Risk Assessment (3MRA) Model.17 The May 16, 2001, HWIR-waste rule revised and retained the hazardous waste mixture and derived-from rules as previously discussed in this module. In addition, the rule finalized provisions that conditionally exempt mixed waste (waste that is both radioactive and hazardous), if the mixed waste meets certain conditions in the rule.5... 

The classification system lacks a set of principles for determining when a waste contains sufficiently small amounts of radionuclides that it can be exempted from regulatory control as radioactive material. The lack of a general class of exempt waste increases in importance as the resources required for management and disposal of radioactive waste increase compared with the resources required for management and disposal of these materials as nonradioactive waste, and it may foreclose possible beneficial uses of slightly contaminated materials. 

As part of this study, proposed radioactive waste classification systems that differ from the existing classification system in the United States were reviewed and evaluated. Of particular interest is the classification system currently recommended by the International Atomic Energy Agency (IAEA). This classification system and the disposal options for each waste class are summarized in Table 1.2. The basic waste classification system consists of exempt waste, low-and intermediate-level waste, and high-level waste. 

The similarities are of the following kinds. First, neither classification system includes a general class of exempt waste. Second, neither classification system is comprehensive, because the classification system for radioactive waste distinguishes between fuel-cycle and NARM waste and the classification system for hazardous chemical waste excludes many potentially important wastes that contain hazardous chemicals. Third, any waste must be managed and disposed of in a manner that is expected to protect public health and the environment. In addition, the approach to disposal of hazardous chemical waste under RCRA, which emphasizes monitoring of releases from disposal facilities and an intention to maintain institutional control over disposal sites for as long as the waste remains hazardous, is applied to disposal of uranium or thorium mill tailings under AEA. 

Management and disposal of hazardous chemical waste under RCRA is based on detailed and prescriptive technical requirements that apply to any facility for waste treatment, storage, or disposal, whereas management and disposal of low-level radioactive waste is more flexible because AEA allows consideration of waste- and site-specific factors. As a consequence, acceptable approaches to management and disposal of mixed low-level waste probably will be determined primarily by RCRA requirements, unless exempt levels of hazardous chemicals are established that render the waste nonhazardous under RCRA. 

A general class of exempt waste, which could be regulated as nonhazardous material, would be established. Development of an exempt class of waste that contains low levels of hazardous substances has been controversial and currently is banned by law in the case of radioactive waste. Some radioactive and hazardous chemical wastes have been exempted on a case-by-case basis, but general principles for exempting radioactive or hazardous chemical wastes have not been established. In spite of these difficulties, however, a meaningful risk-based waste classification system must include a general class of exempt waste. 

This Section describes the concepts used in exempting waste that contains radioactive material and discusses efforts in the United States to establish exemption levels for radioactive waste. 

Concepts and definitions. Two concepts are potentially useful in establishing exemption levels for radioactive waste. The first is the concept of a generally applicable negligible (de minimis) dose or risk, and the second is the concept of amounts of radionuclides that are exempt or below regulatory concern (BRC) for particular practices or sources. 

Exemption levels for radioactive waste. This Section discusses exemption levels for radionuclides in waste materials that have been established or were proposed by NRC. Exemption levels for radioactive waste have not been established by DOE or EPA. 

Summary of exemptions for radioactive waste in the United States. At the present time, exemption levels for radionuclides in waste materials, or materials intended for beneficial use,... 

NCRP has developed a recommendation on a negligible individual dose that could be used to establish exemption levels for radioactive waste for such purposes as disposal and recycle/reuse, but this recommendation has not been adopted by regulatory authorities. Indeed, NRC is prohibited by law from implementing a proposed generic policy on exemption of radioactive materials that was consistent with the NCRP recommendation. 

IAEA Recommendations on Radioactive Waste Classification and Exemption Principles... 

A number of alternatives to the qualitative and source-based classification system for radioactive waste in the United States have been proposed. The alternative waste classification systems have three important features in common. First, they are comprehensive, in that NARM waste and nuclear fuel-cycle waste are included in the same classification system. Second, they are based on the concept that waste classes should be defined primarily on the basis of risk, particularly the risk resulting from waste disposal. Finally, to some degree, they associate waste classes with particular disposal systems that are expected to be generally acceptable. None of these features is embodied in the radioactive waste classification system in the United States. In addition, some proposed classification systems include an exempt class of radioactive waste that contains negligibly small amounts of radionuclides. Waste in this class would be regulated in all respects as if it were nonhazardous. A general class of exempt waste is not included in the radioactive waste classification system in the United States. 

Previous sections have presented technical and historical information on radiation and chemical risk assessment and on classification of radioactive and hazardous chemical wastes. This information provides important perspectives for establishing the foundations of a new hazardous waste classification system. Before establishing these foundations, it is useful to specify the attributes that an ideal waste classification system should possess. The following sections identify the desirable attributes of a waste classification system including that the system should be risk-based, it should allow for exemption of waste, and it should be comprehensive, consistent, intrinsic, comprehensible, quantitative, compatible with existing systems, and flexible. These attributes should be recognized as goals that are not all likely to be fully realized in a practical waste classification system. 

The most profound change in waste classification that would result from implementation of the system proposed in this Report would be the establishment of an exempt class of waste. This class would be defined based on the principle that waste could be regulated as if it were nonhazardous if the hazardous constituents were present in amounts sufficiently low that the risk from disposal would be negligible (de minimis). At present, EPA has not established general provisions for exemption of listed hazardous chemical wastes regulated under RCRA, and efforts by NRC to establish general conditions for exemption of radioactive wastes were halted at the direction of Congress. 

A striving to embody all the desired attributes of the new system, while recognizing that this may take many years and that a number of important benefits can be obtained by interim implementation of parts of the system. The most important areas in which interim implementations are likely to be beneficial include the establishment of exemption levels for radionuclides and hazardous chemicals in waste, to allow hazardous wastes to be managed as nonhazardous material or to allow mixed waste to be managed as radioactive or hazardous chemical waste only, and the elimination of source-based definitions of hazardous wastes, especially radioactive wastes. 

Radioactive waste is any material that contains, or is contaminated with, radionuclides at concentrations of radionuclides greater than the exempted quantities established by the regulatory body and for which no future use is foreseen. This is after a definition by IAEA. 

The main purpose of this Act is to ensure effective control over radioactive wastes. Under the Act those who keep or use radioactive materials on premises used for the purposes of an undertaking (trade, business, profession etc.) are required to register with Her Majesty s Inspectorate of Pollution of the Department of the Environment, Welsh Office, Her Majesty s Industrial Pollution Inspectorate for Scotland of the Scottish Development Department or the Department of the Environment for Northern Ireland, according to the region, or to be exempted from registration. Conditions may be attached to registrations and exemptions, and these are made with regard to the amount and character of the radioactive waste likely to arise. 

Furthermore, no person may dispose of or accumulate radioactive waste unless he is authorised by the appropriate Department or is exempt. Whenever possible local disposal of radioactive waste is arranged but with many industrial sources such as those used in gauges and radiography it is necessary to use the National Disposal Service. 

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