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The Regulatory Framework MECHANICS OF EXISTING AND FORMER STANDARDS GOVERNING RELEASES OF RADIOACTIVELY CONTAMINATED MATERIAL The technical assumptions underlying existing and former radiation stan- dards are integral to the standards themselves and thus critical to evaluating them. In this section, the study committee reviews several of the most important con- cepts used in establishing radiation standards, including dose-based versus activ- ity-based standards, the role of calculated simulations in assessing risks, the importance of defining critical groups, and important uncertainties in assessing risks (see Box 2-1 for description of different types of radiation standards). The general trend in environmental regulation is toward risk-based stan- dards, which typically focus on the estimated increased lifetime risk of cancer posed by the regulated material (NRC, 1994~. Certain statutes, however (e.g., sections of the Clean Air Act), continue to use technology-based standards. That is, they prescribe the use of a particular control technology rather than establish- ing an acceptable exposure level. Calculating the health risks associated with a radioactively contaminated object involves a two-step process. First, the dose must be calculated, which entails constructing a range of scenarios to represent the range of potential doses to individuals. Second, for each estimated dose, the attendant health risk or harm must be estimated. As discussed below, both steps necessarily introduce uncertainties and typically use simplifying assumptions. The virtues of a risk-based approach are that it establishes standards close to the level of public health concern, ensures that contaminant levels are controlled 33

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34 THE DISPOSITION DILEMMA to achieve acceptable levels of public health protection, and promotes consis- tency among different regulations. Risk-based standards are meant to be respon- sive to public policy decisions on widely acceptable levels of risk and are pre- sumed to be rationally based on carefully conducted estimates of dose and risk. The unavoidable uncertainties in risk-based standards are therefore more than offset by their capacity to incorporate policy determinations into a rigorous, scientifically based framework. However, an important challenge is to ensure

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THE REGULATORY FRAMEWORK 35 that the methods used, including their simplifying assumptions and inherent con- straints, are sufficiently transparent to both technical peers and the concerned public. As noted earlier, two types of standards exist in the area of radiation safety for slightly radioactive solid material (SRSM). One type is based on the level of radiation exposure, or dose. The other is based on the level of radioactivity of the material in question and is therefore often called an activity-based standard. Superficially, a radioactivity-based standard appears to be the more direct of the two approaches because it prescribes a maximum level of radiation that may be emitted by an object that is to be used or disposed in a specified manner. A radioactivity-based standard does not appear to require the complex process of assessing how individuals might be exposed to the object's radioactivity and what the resulting doses are likely to be. Technical analyses such as draft NUREG-1640 (USNRC, 1998b) derive radioactivity-based limits for selected disposition cases that are based on risk or dose limits (see Chapter 5~. However as discussed further below, whether there is in fact a significant difference in com- plexity between these two types of standards depends on whether the governing regulation is based on technology (i.e., a control or measurement limitation) or on limiting exposure, hence risk. Technology-Based Regulations Regulatory standards may be based on the limitations of existing control or measurement technologies. The U.S. Nuclear Regulatory Commission's (USNRC's) existing guidance document concerning release of solid materials with surface contamination from regulatory control, developed in the 1970s, is based on the decontamination survey practices that were in use at that time (see Box 2-2~. Some environmental laws, such as specific provisions in the Clean Air Act, base regulations on the "best available control technologies." In this ap- proach to regulation, the focus is not on risk, which is difficult to estimate and even harder to defend, but on promoting the use of the most advanced technolo- gies and fostering their further development. Regulations that require the use of best available control technology obviate the need for dose estimates. In some instances, specifying activity limits is not necessary. The salient issue is maximizing the use of the most effective control technologies. To achieve this, a regulation could prescribe limits on radioactivity levels (e.g., annual emissions limits on radionuclides) or require that specified instruments or methods, and defined limits, be employed when radioactively contaminated materials are monitored. To a large degree, the existing guidance embodies this latter principle, relying on extensive guidance for procedures and practices (AEC, 1974; USNRC, 1981~. Technology-based regulation has the advantage of being relatively simple to implement. It avoids the complexities of determining the myriad ways in which

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36 THE DISPOSITION DILEMMA people might be exposed to radiation from radioactively contaminated materials. A major disadvantage, however, is that if the approach were applied in total ignorance of the potential harms, it could result in either serious underregulation and thus increased risk to the public or overregulation and hence increased costs to the regulated industries. Thus, when developing technology-based regulations, regulatory agencies are well advised to conduct at least brief analyses of the risk reduction and cost-benefit achieved by the specific technologies that might be implemented. Risk-Based Regulations In practice, many standards are a hybrid of dose-based and activity-based approaches. For example, any risk-based standard, whether its allowed maximum levels are expressed as doses or radioactivity levels, entails that the ultimate dose to a certain class of individuals, termed the "critical group," be assessed. To bound the analysis in the assessment requires fairly elaborate simulations and numerous technical judgments. The inherent uncertainty associated with these

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THE REGULATORY FRAMEWORK 37 simulations and judgments varies with the quality of data and the range of poten- tial exposure scenarios that must be considered. Constructing Critical Groups and Exposure Scenarios Often, relatively clear bounding hypotheses for the analysis can be identified by using conservative assumptions about possible routes of exposure. For ex- ample, in developing its analyses for risk-based standards, the Environmental Protection Agency (EPA) has sought to identify plausible examples from which significant exposures could arise. It uses these exposure scenarios to construct the critical groups for the analysis. The doses to these critical groups, estimated by simulating the exposure scenario, dictate the level of radioactivity that is permit- ted in materials subject to regulation. As an illustration of how critical groups are used, one critical group consid- ered by the EPA is represented by an operator of an industrial lathe made with radioactively contaminated cast iron. This is a relatively high-dose scenario be- cause of the time spent next to the radioactive object, as well as its size and proximity. The larger the object, given the same concentration of radioactive material, and the longer the time in proximity, the higher is the exposure (EPA, 1997a). In most cases, as in the above example, the doses to the critical groups are constructed to provide the upper bound on what is permissible under the regula- tion. The method assumes that most of the public will be exposed to far lower levels of radiation than would members of the critical groups. An important question that is frequently raised about such simulations is whether exposure from a number of different sources could lead to much higher levels of risk. Returning to the example of the lathe operator, multiple exposures would occur if this individual were exposed not only to radiation from the indus- trial lathe but also to radiation from cast iron cooking utensils and large home appliances. In theory, these multiple routes of exposure could raise the individual's exposure above the level that the applicable regulation is attempting to ensure is not exceeded. Regulators work to account for the potential that multiple exposures will occur by using information on the volume of materials at issue, the materials' potential uses, the relative importance of different routes of exposure, and the circumstances under which the materials are used (EPA, 1997a). Using this infor- mation and a conservative set of assumptions, regulators attempt to assess the likelihood and importance of multiple exposures. For completeness, it is impor- tant to take into account the potential for such multiple exposures, even where the levels of contamination in the materials are very low, since multiple exposures can result in a higher dose to an individual than originally analyzed. Allowance for multiple exposures may be in the form of choosing a level for a standard that reflects the likelihood of multiple exposure. Thus, the standard for release of a

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38 THE DISPOSITION DILEMMA site may be a relatively large fraction of the public exposure safety limit, while the standard for release of material into commerce would be a much smaller fraction, even a de minimis level. Uncertainty and Sensitivity of Analytical Assumptions The inherent complexity of dose assessment analyses requires that numerous simplifying assumptions be made. For example, assumptions must be made about the length of time a person spends next to a contaminated object and at what distance, as well as whether the contaminated material is mixed with clean mate- rials before being fabricated into a consumer product. These assumptions and the variability in the quality of information available mean that the exposure simula- tions on which the analysis depends are subject to significant uncertainties. These uncertainties are typically difficult to quantify. If overly conservative assump- tions are used in the analysis, the assessment will err on the side of caution. Conversely, if simplifying assumptions minimize or underestimate potential risks, the assessment will err toward inadequate control to protect health and safety. If uncertainty distributions or ranges for the input assumptions are available, ana- lysts can perform studies, using methods such as Monte Carlo simulations, to obtain estimates of the uncertainties in the dose calculations or other predictions from the analysis (see Chapter 5 for further discussion). In addition to uncertainty, the difference that any given assumption makes to the overall analysis can be quantified by using a sensitivity analysis. The sensitiv- ity of the final dose estimate to a particular input assumption or factor is mea- sured by varying the value assumed for that assumption without varying any other factors. Although Monte Carlo simulations and sensitivity analyses can be compli- cated by variables that are strongly dependent, they provide an important means by which analysts can gain a qualitative sense of the reliability, or variability, of their estimates and an understanding of what factors are most important. Regula- tors therefore have at their disposal an array of analytical methods that can be used to assess whether their judgments are reasonable. Critical Uncertainties Although the analytical methods employed by regulators in establishing stan- dards have become increasingly sophisticated, uncertainty and judgment are un- avoidable in assessing potential risks and deciding how much extra conservatism to embed in the regulations. In the present context, there are several particularly important uncertainties, which the committee discusses at several points in this report. Among these uncertainties are the following: The risk that radionuclides will concentrate in certain solid materials that

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THE REGULATORY FRAMEWORK 39 are unconditionally released into commerce; The limits on existing radiation monitoring equipment and survey meth- ods; The significance of multiple potential exposure pathways for cumulative exposure to the public; and The reliability of conservative, or bounding, hypotheses in designating critical groups. . The consequences of these uncertainties for assessing risks associated with radionuclides are particularly complex because many radionuclides are long- lived and because monitoring for low levels of radioactivity requires sophisti- cated instrumentation and rigorous methods. In making conservative estimates, regulators must carefully take these factors into account. As discussed in Chapter 5, analysts attempt to incorporate these factors into their calculations and assess their significance, at least qualitatively. HISTORICAL EVOLUTION OF THE REGULATORY FRAMEWORK FOR CONTROLLING RADIOACTIVELY CONTAMINATED SOLID MATERIALS Under the Atomic Energy Act of 1946 as amended in 1954 (AEA), the Atomic Energy Commission (AEC) and its successor agency, the USNRC, were granted the authority to regulate radioactive materials associated with nuclear fission. These materials are categorized in the AEA as source materials (i.e., uranium and thorium), special nuclear materials (e.g., plutonium), and byproduct materials (e.g., most radioactive material including common radioactive wastes) (42 U.S.C. 2073, 2091, 2111~.1 Byproduct material includes any radioactive material (except special nuclear material) yielded in or made radioactive by the process of nuclear fission. This process includes both fission fragments (fission products) and activation products (42 U.S.C. 2014(e)~.2 Notably, the AEA does cover naturally radioactive source materials, but does not cover naturally occur- ring radioactive material (NORM) (e.g., radon gas), technologically enhanced 1References to the United States Code (U.S.C.) are given parenthetically using the conventional format with the title number first (Title 42 in this reference), followed by the initials U.S.C. and the section numbers within the title. 2The Uranium Mill Tailings Radiation Control Act of 1978 (Public Law 95-604) added a second category of byproduct materials at section ll(e)(2) of the AEA, defining them as the "tailings" or waste produced by the extraction or concentration of uranium or thorium from any ore processed primarily for its source material (i.e., uranium or thorium) content. This and other terms have been paraphrased from their original sources, the Atomic Energy Act and 10 CFR Part 20. These sources should be consulted with regard to the precise legal meaning and effect of these terms.

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40 THE DISPOSITION DILEMMA NORM (TENORM), or materials made radioactive from particle accelerator ex- periments. In establishing the AEC's regulatory authority, the AEA delineated appro- priate regulatory procedures in substantial detail (42 U.S.C. 2073,2091,2111~. It did not prescribe specific technical requirements, deferring instead to the AEC, and later the USNRC, to develop and promulgate requirements for specific ac- tivities. Accordingly, all activities that were to be licensed by the AEC originally required the applicant to submit technical justifications for the proposed practice and to undergo a case-by-case review for authorization. Over time, specific re- quirements have been established for recurring or routine license applications. Regulatory Practices and Controls Title 10 (Energy) of the Code of Federal Regulations establishes licensing requirements for all practices using nuclear materials under the jurisdiction of the USNRC and agreement states. Examples include 10 CFR Part 40 for source material, 10 CFR Part 50, et seq., for facilities that produce or utilize special nuclear material, and a series of regulations beginning with 10 CFR Part 30 for byproduct material. These regulations codify licensing requirements in a generi- cally applicable way to the extent possible. The USNRC issues two basic types of licenses, specific and general. A specific license is required for practices involving significant quantities of nuclear material that warrant licensee control employing at least one radiation control professional. Commercial nuclear power plants, for example, are operated under a specific license issued by the USNRC. A general license may be issued if the quantity of nuclear material is significant but adequately protected through de- sign and administrative controls (e.g., an industrial gauge that uses a strong radiation source). General licensees are not required to have radiation control professionals but are required to use a generally licensed device under the speci- fied controls. The design and administrative controls are imposed through the specific licensee who makes and distributes a generally licensed device, as well as the end user of the device. Certain radioactive materials may be deemed exempt from regulation if the amount of radioactive material involved is small enough or adequately protected by design. Examples include ionization smoke detectors and the small quantities and concentrations listed as exempt in 10 CFR 30.70, 30.71. Extensive regulations govern the disposal of radioactive wastes generated by or from licensed facilities. The regulations for high-level radioactive waste, 10 CFR Part 60 and Part 63, define high-level radioactive waste by its origin, not its radioactive content, and delineate detailed requirements for its licensed disposal. The disposal requirements for the three classes of low-level radioactive waste (LLRW) are contained in 10 CFR Part 61. Although these regulations impose upper bounds on the radioactive content for Class A, B. and C low-level waste,

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THE REGULATORY FRAMEWORK 41 they do not specify a floor or threshold content of radioactivity below which material may be treated as nonradioactive waste. Accordingly, under existing regulations there is no generally applicable criterion for determining that the radioactive content in solid waste is de minimis.3 Formal USNRC regulations are augmented by a series of guidance docu- ments, referred to as "Regulatory Guides," that establish preferred or acceptable methods for regulatory compliance purposes. Regulatory Guides are developed and proposed by committees of technical experts in a specific area, such as radiation monitoring or facility engineering requirements. If the USNRC en- dorses a proposed practice, it is formally published as a Regulatory Guide. Lic- ensees who adopt a Regulatory Guide by incorporating it by reference in their license application are subject to inspection and enforcement of its requirements. A license applicant may choose instead to propose different practices for special reasons. However, doing so can lead to substantial delays in licensing decisions. One such guidance document, Regulatory Guide 1.86, Termination of Oper- ating Licenses for Nuclear Reactors (AEC, 1974), is of particular interest to the study committee's task (see Box 2-2~. Issued in June 1974, this guide was re- leased in the midst of the transition from the former AEC to the newly established USNRC. This was also the time when the first generation of demonstration power reactors was decommissioned. Unlike the typical document in this series, Regu- latory Guide 1.86 was not developed by an expert committee; it was promulgated as a placeholder to enable reactor decommissioning to proceed. Thus, it enumer- ates licensing administrative requirements and different approaches to reactor decommissioning and specifies, in its fourth and final section, a systematic ap- proach for license termination and release of equipment and the site. Regulatory Guide 1.86 includes a table, Table I, of acceptable surface con- tamination levels. This AEC guidance for permitting clearance of radioactive materials dates back more than 25 years, to the initial preparation of Regulatory Guide 1.86. The Table I guidance had been in informal use for some time before 1974 and apparently was based on the detection limits of the instruments avail- able at that time, not on an assessment of risk.4 Table I contains guidance on clearance standards for surfaces such as floors, walls, structural materials, and equipment; it contains no standards for volume contamination. The table, which became the USNRC's de facto standard for clearance of solid materials with residual surface contamination, has been widely used for decades. Selecting a clearance level requires that specific implementing protocols be developed. Office of Inspection and Enforcement (IE) Circular No. 81-07, Con- 3For two radionuclides only, in solid materials, and in one specific application, section 2005(a)(2) of 10 CFR Part 20 does contain release criteria. These criteria allow disposal of volume-contami- nated animal tissue containing less than 1.85 kBq/g of 3H or 14C as if it were not radioactive. 4The committee was not able to uncover substantial evidence that this early work was based on an assessment of risk.

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42 THE DISPOSITION DILEMMA trot of Radioactively Contaminated Material, provides guidance on radiation control programs, including material clearance protocols (USNRC, 1981~. It con- tains guidance for implementing the surface contamination standards in Table I, such as data on radiation detection instrumentation, as well as radiation control systems required generally of licensees. Like Regulatory Guide 1.86, this guid- ance is not specific to volume-contaminated materials. Authorized Releases of Radioactive Materials from Regulatory Control Existing and Proposed Standards The USNRC's general radiation protection regulations in 10 CFR Part 20 prescribe acceptable radiation exposures for workers and the public, as well as permissible levels of radioactivity in gaseous or liquid emissions from licensed facilities. Section 2002 of Part 20 provides for a case-by-case review to obtain approval to dispose of radioactive materials in unlicensed facilities when proce- dures are not specifically prescribed by existing regulations. (The USNRC re- ceived approximately 15 such requests over the past 5 years [USNRC, 2001bj. As the committee understands it, these requests cover only proposed disposals that are different from standard practices.) In addition to the requirements specified in Part 20, the USNRC frequently incorporates directly into a facility's license specific requirements for release of certain radioactively contaminated solid materials. Except for the exemption tables in 10 CFR Part 30, general standards for the unrestricted release of vol- ume-contaminated solid materials have not been promulgated. First in 1986 and again in 1990, the USNRC proposed to formalize and update the existing guidance and other regulations by establishing policies on radiation levels that would be considered "below regulatory concern" (BRC). These proposals were meant to establish a threshold for residual levels of radio- activity, below which the solid material could be cleared from further regulatory control. Section 10 of the Low-Level Radioactive Waste Policy Amendments Act of 1985 (42 U.S.C. 2021j) specifically addresses low-level waste. Consistent with this statute, the proposed BRC policy attempted to set general criteria for allowable individual dose and collective doses resulting from authorized releases of radioactively contaminated materials from licensed activities. The BRC proposal was intended to be an overarching approach that would establish specific quantitative standards for site releases at license termination, unrestricted release of waste materials, and consumer or industrial product uses of radioactive materials, as well as other standards. In some quarters, however, this proposal was perceived as a subterfuge to reclassify a large part of the low- level waste from commercial reactors as nonradioactive waste, thereby allowing Collective dose is the sum of the individual doses received, in a given period of time by a specified population, from exposure to a specified source of radiation.

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THE REGULATORY FRAMEWORK 43 licensees to avoid the costs of disposal at a licensed LLRW facility (USNRC, 1991a). Many comments from the general public, the states, and Congress re- jected the BRC approach for releasing radioactively contaminated materials for unrestricted reuse or disposal. In response to these criticisms, the USNRC placed a moratorium on the proposed BRC policy while it attempted to build public consensus for it. That effort failed, and Congress formally revoked the BRC policy in the Energy Policy Act of 1992. The USNRC rescinded its proposed BRC policy statement soon afterward. In response to the USNRC's deregulation efforts, at least 16 states subse- quently passed regulations or laws that were stricter than the federally proposed allowable releases. The intent evident in most of these new restrictions was to continue regulatory control if the federal government allowed deregulation. Ma- jor concerns voiced by the public included the uncertain risks, a lack of confi- dence in the USNRC and the Department of Energy (DOE), and general concerns about the release of radioactive materials into consumer products (USNRC, l991a,1991b). Chapter 8 provides further details on public reactions to the BRC proposal. The committee has been asked to address questions related to a proposal that may be considered another attempt by the USNRC to establish uniform standards for the unrestricted release of SRSM. In 1998 the Commission directed the USNRC staff to consider a rulemaking for establishing a dose-based standard for release of SRSM (USNRC, 1998a), and in January 1999 the USNRC initiated an enhanced participatory rulemaking directed at establishing a clearance standard (USNRC, l999c). At the same time, the USNRC sponsored a draft technical report on the topic, NUREG-1640, Radiological Assessments for Clearance of Equipment and Materials from Nuclear Facilities (USNRC, 1998b). This draft report was criticized severely when concerned parties learned that the contractor developing the draft, Science Applications International Corporation (SAIC), was concurrently also doing work for a company that stood to gain financially from the promulgation of a clearance standard. The USNRC published an issues paper in the Federal Register (64 Federal Register 35090-35100; June 30, 1999) and held a series of public meetings from September through December 1999. Its proposal for rulemaking on release crite- ria aroused the same skepticism that had greeted its earlier BRC policy. Con- sumer and environmental groups were particularly incensed that in their view, the USNRC had predetermined the outcome before it started. These concerns led to a broad-based boycott of the first two 1999 public meetings. At the same time, the USNRC, through its contract with SAIC, was conducting a detailed technical analysis that would become NUREG-1640 to assess the risks associated with establishing a clearance standard. As discussed in the section "Stakeholder In- volvement" below, significant concerns about public health and safety issues and negative economic impacts on certain industries were raised. A USNRC paper summarizing the public meetings, technical bases, and alternatives was issued on

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44 THE DISPOSITION DILEMMA March 23, 2000 (USNRC, 2000a). A final stakeholder briefing occurred on May 9, 2000. As part of its response to the concerns expressed at these meetings, the Commission requested that a study be undertaken by the National Academy of Sciences. COMPARATIVE ASSESSMENT OF EXISTING REGULATIONS IN THE UNITED STATES There are numerous regulations in the United States governing releases of radioactively contaminated materials and facilities. Three agencies the USNRC, DOE, and EPA have promulgated regulations and/or guidance according to their respective statutory authorities. The standards range from about 1 mrem/yr (USNRC' s Regulatory Guide 1.86, as estimated in USNRC, 1998b), to 100 mrem/ yr (10 CFR Part 20.1301, which limits the annual dose received by members of the public from a licensee), to 500 mrem (10 CFR Part 35.75, which allows a licensee to release a person who has received radiopharmaceuticals provided doses to other persons will not exceed 500 mrem). In radiation control the USNRC generally applies the standards as limits supplemented by explicit steps to main- tain the exposures at levels that are as low as reasonably achievable (ALARA). The EPA generally applies specific limits to specific applications. While there is general agreement among the three agencies, differences persist with regard to standards for protection of groundwater and for an all-pathways dose. Even within one agency' s regulations, there are apparent discrepancies. For instance, the can- cer risks associated with EPA standards for water, air, and Superfund cleanup range over more than two orders of magnitude (NRC, 1999~. In summary, the levels of protection afforded by federal regulation of radioactive materials vary widely. USNRC Regulations There are two sets of USNRC regulations for unrestricted release. One set pertains to the release of facilities from regulatory control; the other pertains to materials to be released on an unrestricted basis from regulated facilities. Each set of regulations provides for significant regulatory flexibility depending on the circumstances. The USNRC's License Termination Rule: Release of Facilities The USNRC's License Termination Rule, 10 CFR Part 20, Subpart E, gov- erns unrestricted and restricted release of USNRC-licensed facilities from regula- tory control. This rule establishes procedures and specific standards that must be met before regulatory oversight of a facility can be terminated. The rule's key requirements are as follows:

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THE REGULATORY FRAMEWORK 45 Unrestricted release of a USNRC-licensed facility is permitted if the all- pathways dose, including groundwater, does not exceed 25 mrem/yr and radioactive residues have been reduced to levels that are ALARA. Restricted release of a USNRC-licensed facility is permitted if (1) the net public and environmental harm is comparable to compliance with the 25 mrem/yr limit for unrestricted release and the residue levels are ALARA; (2) institutional controls are adequately funded and legally enforceable; (3) requirements for restricted release have the advice of a broad cross section of the community interests; and (4) in the event that institutional controls fail, the maximum dose is ALARA and does not exceed 100 mrem/yr (or 500 mrem/yr under exceptional circumstances substantiated by detailed information). Alternative criteria may be submitted by a licensee for review if they are sup- ported by adequate plans and analyses prepared with community advice. The dose limits apply to the total effective dose equivalent for the average member of the critical group, calculated over the first 1,000 years after decommissioning. The USNRC's Case-by-Case Approach: Release of Materials Overview. As noted in Chapter 1, the USNRC's regulations under 10 CFR Part 20 limit the radiation dose that an individual can receive from the operation or decommissioning of a USNRC-licensed facility and also require that doses re- ceived are ALARA. Although Part 20 sets standards for releases of effluents (liquids or gases), it sets no specific standard for release of solid materials with surface or volume contamination.6 The USNRC generally evaluates releases on a case-by-case basis using license conditions and existing regulatory guidance. 6According to the USNRC (1999a): For most NRC licensees, solid materials have no contamination because these licens- ees use sealed sources in which the radioactive material is encapsulated. These include small research and development facilities and industrial use of various devices including gauges, measuring devices, and radiography. For other licensees (including nuclear reactors, manufacturing facilities, larger educa- tional or health care facilities, including laboratories) materials generally fall into one of three groups based on its location or use in the facility: Clean or unaffected areas of a facility, from which areas the solid materials would likely have no radioactive contamination; Areas where licensed radioactive material is used or stored, from which areas mate- rials can become contaminated although the levels would likely be low to none; and Material used for radioactive service in the facility or located in contaminated areas or areas where contamination can occur, from which materials generally have levels of contamination that would not allow them to be candidates for release unless they are decontaminated.

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46 THE DISPOSITION DILEMMA In Section 2002 of Part 20, "Method for obtaining approval of proposed disposal procedures," the basis for the case-by-case review is virtually the same as that in the old Section 302 of Part 20. As noted above, neither version provides specific standards for exemption.7 The pertinent portion of Part 20.2002 reads as follows: A Licensee or applicant for a license may apply to the Commission for approval of proposed procedures, not otherwise authorized in the regulations in this chap- ter, to dispose of licensed material generated in the licensee's activities. Each application shall include: a. A description of the waste containing licensed material to be disposed of, including the physical and chemical properties important to risk evaluation, and the proposed manner and conditions of waste disposal; and b. An analysis and evaluation of pertinent information on the nature of the environment; and c. The nature and location of other potentially affected licensed and unlicensed facilities; and d. Analyses and procedures to ensure that doses are maintained ALARA and within dose limits in this part. Under the case-by-case approach, the USNRC does not consider most re- leases of solid materials to be "disposals" authorized under Part 20 or Part 61. Instead, these releases are frequently authorized by specific license conditions, that is, a specific provision contained in the facility's license.8 Categories of Release. USNRC guidance on release of SRSM falls into three categories: (1) release of solid materials with surface residual radioactivity at reactors, (2) release of surface-contaminated solid materials possessed by a mate- rials licensee (i.e. nonreactor licensee), and (3) release of volume-contaminated solid materials possessed by reactor and materials licensees (USNRC, 2001b). The guidance for each category is summarized next. 7The 1957 issue of Part 20 had a short section on waste disposal that included Part 20.302, "Method for obtaining approval of proposed disposal procedures," the basis for case-by-case review of disposal procedures not authorized by the two succeeding sections on disposal in sewerage sys- tems or in soil. The original Part 20 gave general requirements for waste disposal of byproduct material. The 1957 standard did not include any criteria for a floor to the amount or concentration of controlled radionuclides, which criteria might be used as the basis for exemption of waste from regulatory control. sit is not appropriate to apply the ALARA principle at or below the dose limits that are typically proposed for clearance calculations. These are not dose safety limits in the ordinary sense of the word, but are levels at which SRSM may be released from regulatory control. The dose limits of 0.1 to 10 mrem/yr are already orders of magnitude below natural background levels. Additionally, the variation in natural background dose is larger than the level of the selected dose limit. Since the proposed dose limits are already well below most established safety limits, it is not appropriate to apply the ALARA principle to the clearance dose limits as calculated in NUREG-1640.

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THE REGULATORY FRAMEWORK 47 Release of solid materials with surface residual radioactivity at reactors. Reactor licensees typically follow a policy established by IF Circular 81-07, Control of Radioactively Contaminated Material, and Information Notice 85-92, Surveys of Wastes Before Disposalfrom Nuclear ReactorFacilities(USNRC, 1981, 1985~. Under this policy, reactor licensees must survey equipment and material before its release. If the survey indicates the presence of licensed AEA material above natural background levels, the equipment or material cannot be released (USNRC, 2001b). The IF Circular 81-07 and related guidance basically set the sensitivity required of survey instruments, a sensitivity similar to that used in applying Regulatory Guide 1.86. Release of surface-contaminated solid materials possessed by a materials lic- ensee (i.e., nonreactor licensee). For materials licensees, the USNRC usually authorizes the release of solid material through specific license conditions. Table I of Regulatory Guide 1.86 is used to evaluate surface contamination on solid materials before they are released (AEC,1974~. Similar guidance is found in Fuel Cycle Policy and Guidance Directive FC 83-23, Guidelines for Decontamination of Facilities and Equipment Prior to Release for Unrestricted Use or Termina- tion of Byproduct, Source or Special Nuclear Materials Licenses (USNRC,1983~. Both documents contain a table of surface contamination criteria, which may be used by licensees as the basis for demonstrating that solid material with surface contamination can be released safely with no further regulatory control. Release of volume-contaminated solid materials possessed by reactor and mate- rials licensees. The USNRC has not provided guidance for volume-contaminated materials analogous to the guidance in Regulatory Guide 1.86 for surface con- tamination. Instead, the USNRC has decided these situations on a case-by-case basis by evaluating the doses associated with the proposed release of the material. Typically, the evaluation and decision is made in such a way as to ensure that the maximum doses are a small percentage of the Part 20 dose limit for members of the public of 100 mrem/yr. The Role of States. Under the AEA, the USNRC has preemptive authority to license and regulate the ownership, possession, use, and transfer of AEA materi- als source, byproduct, and special nuclear materials and to set standards, as are necessary to protect public health, for the ownership, possession, use, and transfer of AEA materials. However, Section 274 of the AEA specifically autho- rizes the Commission to enter into agreements with states to transfer limited elements of that authority. These agreements constitute a discontinuance of USNRC's authority, not a delegation; a state assumes the USNRC's authority over selected radioactive materials (specifically, byproduct materials, source materials, or special nuclear materials in quantities not sufficient to form a criti- cal mass). Once an agreement is signed, the USNRC continues to have an over-

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48 THE DISPOSITION DILEMMA sight responsibility to ensure that the state, called an "agreement state," has a program for the regulation of ALA material that is adequate to protect public health and safety and is compatible with USNRC regulations (USNRC, l999b). As of December 2001, 32 states had entered into agreements with the Com- mission, and four more states had applied for agreement state status. The USNRC has extensive arrangements and procedures for communicating and interacting with the agreement states, especially to ensure that agreement state regulations are compatible with USNRC regulations. For some USNRC requirements, such as basic radiation protection standards or those that have significant implications for interstate commerce or related activity (sometimes referred to as "transboundary implications"), the agreement state must adopt essentially identical requirements, in order to be compatible with the USNRC. For other USNRC requirements, such as most licensing require- ments, the agreement state has some flexibility to adopt its own requirement if the state's requirements meet the essential objective of the USNRC. States may also establish more restrictive requirements provided that they have an adequate sup- porting health and safety basis and the requirements do not preclude a practice that is in the national interest (USNRC, l999b). Criteria that have been applied by states on a case-by-case basis include the use of radiation levels that are indistinguishable from background, the use of guidelines similar or equivalent to Regulatory Guide 1.86, and the use of dose-based analyses (USNRC, l999b). Cited Advantages and Disadvantages of the Case-by-Case Approach. The USNRC document Control of Solid Materials: Results of Public Meetings, Status of Technical Analyses, and Recommendations for Proceeding (USNRC, 2000a) discusses issues and concerns related to a set of alternatives for establishing control of solid materials. In particular, it summarizes the following broad advan- tages and disadvantages of the current case-by-case approach, an appraisal with which the committee generally agrees: Advantages. The advantages of the case-by-case approach are the following (adapted from USNRC, 2000a): . . It is a flexible tool that is currently in use and well understood. The USNRC staff and licensees have developed a common understanding of the criteria involved. It is protective of public health and safety. The potential exposures re- ceived are a fraction of public health guidelines. Leaving it in place would not involve additional rulemaking resources. USNRC resources would be devoted to specific requests from licensees, which would bear the cost. The USNRC would not have to expend its resources on a rulemaking.

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THE REGULATORY FRAMEWORK Disadvantages. The disadvantages of the case-by-case approach are the fol- lowing (adapted from USNRC, 2000a): . 49 The criteria are inconsistent and incomplete. The absence of uniform criteria for controlling solid materials results in inconsistent release lev- els. Licensees also can have difficulty determining what information to provide for USNRC approval because the existing guidance and criteria may not be clear. The criteria are not risk informed. The current detection-based approach does not relate regulatory requirements to the potential risk that might be associated with the regulated activity. Expenditures of time and resources are required to resolve specific cases. Each review involves establishing and justifying criteria for that case. DOE Standards on Clearance of Solid Materials DOE's standards for surface contamination are set forth in Order DOE 5400.5,9 which incorporates Table I, the surface-activity standards, from USNRC's Regulatory Guide 1.86. At about the same time as the issuance of Regulatory Guide 1.86, the regulatory staff at the AEC were asked to develop solid release standards for volume-contaminated materials from modification of the uranium enrichment plants (see Chapter 5 for a discussion of NUREG-0518~. The development of that standard was set aside after publication of NUREG- 0518 (USNRC, 1980~. Since then, DOE has maintained a policy that generally precluded the release of radioactively contaminated materials for unrestricted use or disposal. Not until Assistant Secretary of Environmental Management Alvin Alm issued a policy statement in September 1996 promoting, on a provisional basis, the recycling of radioactively contaminated scrap steel did DOE formally alter its long-standing policy against unrestricted release of contaminated materi- als. DOE's release policy had initially focused narrowly on restricted end uses of recycled steel at DOE facilities. It was subsequently broadened, at least unoffi- cially, to include recycling into industrial and consumer products generally. The 1996 policy change was implemented on a conditional basis while DOE evaluated the safety and economics of recycling these materials. The first large- scale project involving the recycling of radioactively contaminated materials was initiated at the Oak Ridge Reservation's gaseous diffusion plants, which contain border DOE 5400.5, Radiation Protection of the Public and Environment, Department of Energy, February 8, 1990, revised January 7, 1992. A DOE memorandum dated November 17, 1995, from R.F. Pelletier, provided field and program offices with additional guidance regarding control of residual radioactive material, including the relationship of DOE standards to similar standards set by the USNRC and the states.

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so THE DISPOSITION DILEMMA more than 100,000 tons of contaminated metals (EPA, 1997a; NRC, 1996~. The Oak Ridge project was intended to establish a precedent for a much broader reliance on reuse of radioactively contaminated materials throughout the nuclear weapons complex (NRC, 1996~. Under current estimates, DOE facilities contain about 1 million tons of contaminated metals that could be recycled (EPA, 1997a). Contrary to the recommendations of a prior National Research Council re- port (NRC, 1996), the Oak Ridge project proceeded with little public outreach, and it ultimately provoked significant opposition from the public and the metals recycling industry. In response to this strong opposition from both the private sector and the public, Secretary of Energy Bill Richardson halted further releases of volume-contaminated metals but not surface-contaminated metals from DOE facilities in January 2000. The moratorium was limited to volume-contami- nated metals because no generally accepted regulatory standard or guidance ex- isted. In July 2000, Secretary Richardson reaffirmed this moratorium on volume- contaminated materials and added a temporary suspension on unrestricted recycling of all scrap metal originating from within radiologically controlled areas. He proposed continuing the moratorium and suspension until the USNRC resolved whether to proceed with promulgating a standard governing the clear- ance of radioactively contaminated solid materials. DOE, however, recently ini- tiated the process for drafting a programmatic environmental impact statement on alternatives for recycling surface-contaminated metals (DOE, 2001~. The EPA Role Under the ALA and Reorganization Plan No.3 of 1970, the EPA has respon- sibility for establishing radiation standards, with which USNRC's and DOE's standards must conform. EPA has used its AEA authority to promulgate stan- dards such as 40 CFR Part 190, which sets limits on doses received by members of the public from nuclear power operations. Pursuant to other statutes, EPA has promulgated radiation standards for air emissions and safe drinking water levels. Under the Safe Drinking Water Act, the EPA established a 4 mrem/yr standard for the dose that an individual is permitted to receive from drinking water (40 CFR Parts 141-142~. This standard is based on a single pathway of exposure, under which an individual consumes 2 liters of water per day from a single source of drinking water. Under the Clean Air Act, the EPA promulgated the National Emission Standards for Hazardous Air Pollutants (NESHAP), which permits a 10 mrem/yr dose to the reasonably maximally exposed individual from airborne emission of radioactive materials (40 CFR Part 61~. The basis for this standard includes multiple exposure pathways, including exposure from airborne plumes, inhalation, and ingestion of foods on which radioactive materials have been deposited. In August 1997 the EPA issued guidance on residual levels of radionuclides permitted under the Comprehensive Environmental Response, Compensation,

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THE REGULATORY FRAMEWORK 51 and Liability Act (CERCLA) (EPA, 1997b). The agency premised its standard on the policy that remediation goals for radionuclides should be consistent with a lifetime risk ranging from 10= to 10-6. According to EPA guidance, clearance levels for CERCLA sites cannot result in a dose that exceeds 15 mrem/yr, which EPA guidance states "equates to approximately 3 x 10= increased lifetime risk" (EPA, 1997b). In the context of evaluating potential clearance, or de minimis, standards, the EPA has provided technical analyses in the form of two major studies. In 1997 it completed a draft technical support document, Evaluation of the Potential for Recycling of Scrap Metals from Nuclear Facilities (EPA, 1997a), and a cost- benefit analysis, Radiation Protection Standards for Scrap Metal: Preliminary Cost-Benefit Analysis (EPA, 1997c). The focus of EPA standard setting for unrestricted release has been on pro- moting consistent international import-export controls for materials containing residual radioactivity. This issue has become increasingly important with the erosion of regulatory controls at nuclear facilities in the countries of the former Soviet Union. A number of incidents have occurred in the United States and elsewhere in which radioactive materials have been discovered in scrap metal loads at steel mills and, less frequently, have contaminated the metal used to fabricate consumer products as in the Ciudad Juarez, Mexico, incident in 1983 (Lubenau, 1998~. In 1998 the EPA began to work with the International Atomic Energy Agency (IAEA) on clearance issues and import-export standards. EPA personnel initially worked on technical issues in an effort to promote agreement between the parties on appropriate methodologies for estimating exposure levels. Control of TENORM Naturally occurring radionuclides are found throughout the United States, primarily in the form of elements such as uranium, thorium, radium, potassium, and radon gas (NRC, 1999~. Industrial activities such as oil and gas extraction, water treatment, mining, fossil fuel processing, and aluminum production gener- ate tens of billions of metric tons of TENORM, some of which contain high levels of radioactivity (NRC, 1999~. However, TENORM is not subject to the AEA because it cannot be classified as a source material, special nuclear mate- rial, or byproduct material. Federal regulation of TENORM has been largely absent. In 1986 the Radon Gas and Indoor Air Quality Act directed the EPA to study the dangers of TENORM, particularly radon gas. After completing this study, the EPA drafted proposed rules to regulate TENORM under the Toxic Substances Control Act, which gives EPA the authority to regulate chemical substances, including those that are naturally occurring, that may present an "unreasonable risk of injury to health or the environment" (EPA, 1989~. The EPA's draft proposed rules were

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52 THE DISPOSITION DILEMMA stayed indefinitely. An exception to this void in regulating TENORM is Order DOE 5400.5, which DOE issued under its general responsibility to protect health and safety in conducting activities authorized under the AEA. This regulatory gap persists despite the fact that many forms of TENORM can be substantially more radioactive than LLRW subject to regulation under the AEA (NRC, 1999~. The existing state regulations that apply to TENORM have largely been limited to disposal and handling requirements enacted under the state's general radiation protection laws or under other authority, such as the Resource Conservation and Recovery Act. The Conference of Radiation Control Program Directors (CRCPD) has drafted model state regulations for TENORM, but these have been neither finalized nor adopted by any states. State regulations remain limited and vary greatly from state to state (CRCPD, 1997~. STAKEHOLDER INVOLVEMENT As noted earlier, the current evaluation of clearance of solid materials by the USNRC is not the first time it has attempted to update and formalize guidance for unrestricted releases of SRSM. The most notable prior attempts were those in 1986 and 1990 (discussed above) to establish policy and guidance for solid materials whose residual radioactivity would be "below regulatory concern." These attempts and the subsequent stakeholder reactions provide invaluable in- sight into the current USNRC effort to establish uniform standards for release of SRSM. After the 1990 BRC policy statement was published in the Federal Register (55 Federal Register 27522; July 3, 1990), the USNRC held public meetings in five cities (USNRC, 1991a). These meetings were contentious and well attended by representatives of a large number of stakeholder groups. The USNRC esti- mated that more than 900 people attended, and oral statements were taken from 215 people. The oral statements were supplemented by numerous written ques- tions and comments. "The prevailing sentiment expressed at each of the meetings was one of opposition to the BRC policy and to its implementation" (USNRC, 1991a). In 1991 the USNRC staff reported that three themes were common to the five public meetings. First, "extreme concern was expressed concerning the pos- sibility of deregulation of nuclear power waste." Second, many attendees from the public (including a large number of environmental groups) stated their strong opposition to recycling of materials that could be used in unlabeled consumer products. Third, many attendees perceived that the policy would "permit a large number of deaths per year per practice despite the presence of collective dose criterion" (USNRC, 1991a). In short, stakeholders' concerns expressed at the meetings centered on whether the USNRC could adequately protect the public. Many of these stakeholders also expressed the belief that low levels of radia- tion were much more harmful than the regulatory agencies had determined them

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THE REGULATORY FRAMEWORK 53 to be. This expressed fear was compounded by concerns that it would not be possible to monitor solid materials adequately for radioactivity when they were being surveyed before release. Many of the stakeholders also raised two closely related issues. First, many alleged that the regulatory system failed to take into account multiple exposures. Second, general standards for release would under- mine individual rights to decide the nature and magnitude of the risks to which members of the public would be exposed. These issues continue to be central to stakeholder criticisms. Most of the stakeholder concerns still revolve around safety and protection of the public. The nuclear industry strongly supported the 1990 BRC policy, as did a few other stakeholder groups, on the grounds of economic and resource efficiency. However, the sheer number of groups opposing the policy; the intensity of their viewpoints; and their consistency in raising issues of public health, safety, and welfare doomed this policy from the outset. After the policy was announced in 1990, the USNRC hired a consultant to begin a phased consensus-seeking pro- cess. This effort collapsed shortly after it started because public interest groups refused to engage in the process (USNRC, l991b). As noted above, Congress formally nullified the BRC policy as part of the Energy Policy Act of 1992. Even before Congress acted, the USNRC issued a moratorium on the BRC policy in July 1991 (56 Federal Register 36068-36069; July 30, 1991~; after the Energy Policy Act was signed into law, the USNRC rescinded the policy in August 1993. The BRC policy was defeated largely by the efforts of these public interest groups, which successfully used the political arena to expand the controversy over the issue and to make the issue salient to a large number of stakeholder groups and other interested parties. The lines that were drawn in 1991 over the BRC policy do not seem to have altered appreciably. Many of the public interest groups that the USNRC con- cluded were indispensable to any effort to promote a consensus-seeking process are adamantly opposed to the proposed USNRC rulemaking on SRSM. The only shifts that have occurred are in the positions of officials from several states, whose representatives had opposed the BRC policy solely because of concerns that it would abrogate the states' enforcement authority. However, even among the agreement states from which the committee has heard, there is no consensus on the proposed rule. Many of those who addressed the committee questioned whether such a rule is necessary at all. What lessons, if any, the USNRC has learned from the BRC controversy is a question that the committee addresses in Chapter 9. FINDINGS Finding 2.1. The USNRC does not have a clear, overarching policy statement for management and disposition of SRSM. However, SRSM has been released from licensed facilities into general commerce or landfill disposal for many years

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54 THE DISPOSITION DILEMMA pursuant to existing guidelines (e.g., Regulatory Guide 1.86) and/or following case-by-case reviews. The USNRC advised the committee of no database for these releases. Finding 2.2. A dose-based clearance standard can be linked to the estimated risk to an individual in a critical group from the release of SRSM. The general regu- latory trend is toward standards that are explicitly grounded in estimating risks. Finding 2.3. For clearance of surface-contaminated solid materials, the clearance practices regulated by the USNRC and agreement states are based on the guid- ance document Regulatory Guide 1.86, which is technology based and has been used satisfactorily in the absence of a complete standard since 1974. Finding 2.4. For clearance of volume-contaminated solid materials, the USNRC has no specific standards in guidance or regulations. Volume-contaminated SRSM is evaluated for clearance on a case-by-case basis. This case-by-case approach is flexible, but it is limited by outdated, incomplete guidance, which may lead to determinations that are inconsistent. Finding 2.5. Industrial activities are generating very large quantities of techno- logically enhanced naturally occurring materials (TENORM). Federal regulation of TENORM has been largely absent. State regulations vary in breadth and depth.