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1 Introduction and Background 1.1 INTRODUCTION The U.S. Department of Energy (DOE) manages dozens of sites pri- marily devoted to research, design, and production of nuclear weapons and nuclear reactors for defense applications. These sites are legacies of the Manhattan Project and the Cold War, and some continue to support defense activities. Wastes and contamination at these sites pose a national chal- lenge: DOEâs Office of Environmental Management plans to spend several decades and well over $100 billion to clean them up, and even then waste and contamination will remain. Some of the greatest projected risks, cleanup costs, and technical challenges come from processing and disposi- tion of transuranic (TRU) and high-level radioactive waste (HLW). DOE 3 estimates that it has approximately 340,000 cubic meters (m ) of HLW con- 3 taining about 835 million curies of radioactivity, and at least 287,000 m of TRU waste containing a few million curies of radioactivity at its sites. A multitude of waste streams make up these totals. Deep geologic disposal is 1 the only disposition path contemplated for some of them, but DOE has sought alternative disposition paths for others. 1 The committee uses the term âdisposalâ to mean the emplacement of waste in a facility without the intention of retrieval. âDispositionâ is a broader term referring to 13
14 RISK AND DECISIONS ABOUT TRU AND HLW DOEâs Office of Environmental Management asked the National Re- search Council of the National Academies to provide advice on techni- cally sound approaches for using risk assessment in selecting disposition paths, including alternatives to deep geologic disposal, for its TRU and HLW. To fulfill this request, the National Research Council appointed an eleven-member committee under the auspices of the Board on Radioac- tive Waste Management. The committeeâs statement of task appears in Sidebar 1.1, and biographical sketches of the committee members can be found in Appendix E. Sidebar 1.1: Statement of Task This study will examine risk-based approaches for transuranic and high-level radioactive waste disposition and provide recommendations, as appropriate, on implementation by the Department of Energy in its cleanup program. To this end, the study will explicitly address the following issues: ⢠key elements of a risk-based approach; ⢠criteria for risk assessment; ⢠potential alternatives to geologic disposal for disposition of low- hazard waste; ⢠compatibility with current regulatory regimes; ⢠knowledge and technology gaps for implementation; and ⢠broader implications, if any, for disposition of other DOE wastes. The study also will examine the application of risk-based approaches to selected DOE waste streams to assess their practical usefulness. The waste streams to be examined will be selected in consultation with DOE and regulators to illustrate a range of real-world applications. positioning of waste, whether in interim storage or permanent isolation (disposal) in a repository.
INTRODUCTION 15 Statement of Task The committeeâs charge is to recommend how DOE might imple- ment risk-based approaches for disposition of high-level and transuranic radioactive waste. When discussing a risk-based approach for waste dis- position, the committee views human health risk as the primary analysis outcome, and human health risk is what the committee means when it uses the term risk (unless otherwise qualified). For the sake of clarity, societal or cultural risks (e.g., impacts on community well-being and so- cial cohesion), environmental or ecological risks (e.g., impacts on the environment, ecosystems, and endangered species), and technological or programmatic risks (e.g., the risk that a cleanup technology or a program will not perform as effectively as expected) are considered separately, except to the extent that they affect estimated human health risk. This report focuses on human health risk because it is of concern for all of the waste streams and because it has traditionally been studied in risk analy- sis. However, the committee does not mean to imply that other risks such as ecological or cultural risk are unimportant. A proper risk analysis should identify and consider all of the relevant risks at a given site. When assessing costs one must consider indirect costs such as those incurred by degrading ecosystem services (NRC, 2004). As will become apparent to the reader, the committee believes that it is important to consider all of these factors. In fulfilling its charge, the committee had to consider first whether a risk-based approach is appropriate and desirable in disposing of TRU and HLW. The nation has a system for classification of radioactive waste and disposition options for each waste class. DOEâs cleanup and waste dis- position programs, however, are now the center of great controversy and uncertainty. DOEâs proposals, plans, and declared authority for deciding on on-site, near-surface disposal of waste streams that are (or are made from processing) TRU and HLW have strained its relationships with 2 many of the regulators, nearby American Indian nations, and local communities at the DOE sites. This has left the path forward unclear. 2 The committee uses the term American Indian throughout the report. In the context of this report, in which several different federally recognized American Indian tribal na- tions are active stakeholders and have special rights or claims, the committee decided it is more appropriate to use a general term, rather than list each nation. Also, the committee chose the term American Indian because while there appears to be no consistent prefer- ences among Indigenous American groups for that term or for the term Native American, some term had to be chosen.
16 RISK AND DECISIONS ABOUT TRU AND HLW Thus, the critical questions for these wastes are the following: 1. Should the nation consider pursuing alternatives to deep geologic disposal for some waste currently classified as TRU or HLW? If the answer is âyes,â then other questions must follow. 2. What are legitimate and appropriate bases and processes for de- termining that alternative disposition should be used for a spe- cific waste stream? 3. How should such processes be implemented? The committee has framed its report around these questions and ad- dressed the elements of the statement of task throughout the report. This chapter describes how the committee carried out the study and provides background on TRU and HLW and the requirement for deep-geologic disposal. In Chapter 2, the committee argues that the cost of permanent geologic disposal may be disproportionate to the risks actually posed by some HLW and TRU waste. Chapter 2 also describes the types of wastes that are candidates for seeking alternative disposition paths, potential alternatives to deep geologic disposal for disposition of low-hazard 3 waste, and compatibility with current regulatory regimes. In Chapter 3, the committee argues that our nation should have an explicit mechanism to allow alternative disposition of some fraction of these wastes, rather than taking an ad hoc approach. The committee finds that risk is a good basis or starting point for a process to decide on disposition paths, and describes a system that could allow alternative disposition for a small set of TRU and HLW, using risk as the basis or starting point. The commit- tee describes this approach as risk-informed rather than risk-based to emphasize that risk is one of several factors on which decisions must be based. As described in Chapter 3, the committee focuses on an exemp- tion process for making disposition determinations for problematic wastes because such a process has emerged as the least disruptive way to seek reasonable, appropriate, and acceptable resolution of the disposition questions. Exemptions, as outlined in the report, do not offer direct relief from legal agreements concerning cleanup, but the process recommended in the report provides a persuasive way for DOE to approach renegotia- tion of the agreements. The committee recognizes that there are potential 3 âLow-hazard wasteâ has no consistent or agreed-on definition. In general terms, the committee considers waste that has low concentrations of harmful radionuclides and is in a physical and chemical form that does not facilitate exposure over the duration of the hazard to be low-hazard waste.
INTRODUCTION 17 pitfalls to this approach, nonetheless the committee judged that this was the approach to recommend. Chapter 4 describes the key elements of a risk-informed approach and criteria for risk assessment. Chapter 5 dis- cusses technical and institutional impediments to such an approach, in- cluding knowledge and technology gaps for implementation. Chapter 6 summarizes the committeeâs findings and recommendations. Data Gathering The committee held five information-gathering meetings, including visits to the Idaho National Engineering and Environmental Laboratory (INEEL) in December 2003, the Savannah River Site (SRS) in January 2004, and the Hanford Site in March 2004. Through these meetings and its review of documents, the committee gathered information on DOEâs waste streams and disposition options; how risk assessment is done at the different sites (by DOE and others); and how DOE, regulators, affected American Indian nations, and the public think risk should be used in de- cision making. The committee has endeavored to hear from interested parties at each site by inviting participation by representatives of DOE, its contractors, tribal governments, national laboratory scientists, the U.S. Environmental Protection Agency (U.S. EPA), the U.S. Nuclear Regulatory Commission (U.S. NRC), the states, local governments, and public interest groups. The committee has also invited the general public to participate in open evening sessions at each field location. DOE and participants from each of the other groups and entities, as well as interested individual citizens, have been gen- erous with their time and have shared their knowledge, views, and judg- ment in the course of the meetings and through written input. DOE, regulators, and members of the public suggested numerous HLW and TRU waste streams that might serve as case studies for this report. DOE has also accommodated the preferences and procedural needs of the committee by opening each site tour to members of the public who requested to partici- pate. A list of speakers at each of the committeeâs information-gathering meetings and a list of facilities visited during the tours can be found in Ap- pendix C. All of these interactions have enhanced the committeeâs under- standing of the topic. Prior to each site visit, the committee sent the siteâs DOE field office and other participants lists of questions and requests that presenters were asked to address and that the committee would be probing (see Sidebar 1.2). To evaluate the approach to decision making and how risk figures
18 RISK AND DECISIONS ABOUT TRU AND HLW into the waste disposition process, the committee requested presentations from individuals at DOE who are in charge of specific waste manage- ment and cleanup projects at the sites. 4 As a side note, DOEâs risk-based end states (RBES) corporate project started to become publicly known just as this study began. The coincident timing of the RBES project with the committeeâs study and the similarity in their titles has caused a certain amount of confusion at DOE sites and among the public about the relationship between the two. The RBES pro- ject was not the focus of the committeeâs activities; the committee was not charged with, nor did it undertake, a peer review or other assessment of RBES, per se. However, to the extent that the RBES project represents a use of risk assessment in DOEâs decision making, it was relevant to the committeeâs charge. Consequently, the committee requested presentations and discussions on the RBES project at each of the visited sites. Section 5.4 and Appendix B discuss the RBES project further. Sidebar 1.2: Questions for Information Gathering Questions posed and requests made to DOE: ⢠Wastes. The committee requested from each site a simple table describing the types of waste, their locations, physical and chemical forms, and disposition plans and options. ⢠Disposition alternatives. What alternatives for management, treatment, and disposal of radioactive waste have been exam- ined? What are the health risks, costs, and time lines for each al- ternative? ⢠Risks. What kinds of risks are considered (worker, public, expo- sure pathways and scenarios, etc.)? How are the risks calcu- lated? Under what assumptions and over what time frame? What factors drive the risks for different disposal alternatives? Are those factors and the underlying mechanisms well understood (with reliable models)? What parts of the calculations introduce 4 In 2003, DOE issued a policy stating that every site should formulate cleanup plans by (1) developing an end state vision for the site based on an integrated site-wide plan for future land use, (2) developing exposure scenarios based on the end state, and (3) devel- oping remediation alternatives based on the risks associated with the exposure scenarios (DOE, 2003a);. The deadlines that sites were given to draft the first vision documents coincided with the startup of the committeeâs study.
INTRODUCTION 19 the greatest uncertainties? Do any distinct groups bear greater risk burdens than others? How is the local public involved in the risk assessments? How will risk decisions be implemented? ⢠Regulations. Are there any cases in which the current regulatory structure is thwarting risk-based decisions? ⢠Documents. The committee requested that DOE provide the fol- lowing types of documents for HLW tanks and their residual con- tents and for buried TRU: (1) Detailed risk analyses in support of the current planned cleanup option, (2) detailed risk analyses of any alternative cleanup options that may have been considered, and (3) decision documents that describe weighting of risk and other criteria for decision making (e.g., evidence of incorporation of non-risk considerations). Also, any documents that detail any peer reviews or supporting documentation that explains why the committee, and especially those that are at the receiving end of the particular risks being examined, should believe the results of these analyses to the degree necessary for their use in making decisions. Questions posed to regulators: ⢠Roles and authorities. What is the regulatorâs role in decision mak- ing and disposal of the siteâs high-level, transuranic, and low-level waste, including waste in storage and waste from cleanup? Under what authority does the regulator operate for the different wastes? How do the different regulatorsâ authorities fit together? ⢠Risk in decisions. What kinds and levels of risk are considered acceptable? How does risk factor into decisions in these different cases? What other factors are important? Are there pitfalls asso- ciated with taking a so-called ârisk-basedâ approach to selecting disposal options? Are there specific examples in which regula- tions are incompatible with or prevent DOE from pursuing an op- tion that appears preferable from a risk perspective? Are there any broader implications for disposition of other DOE wastes if a ârisk-basedâ approach is taken for HLW and TRU waste? General questions posed to all parties: ⢠The committee has to select a few waste streams within the DOE complex to examine as case studies. Which waste streams would you suggest? ⢠What information and questions has the committee missed?
20 RISK AND DECISIONS ABOUT TRU AND HLW 1.2 BACKGROUND To understand the committeeâs data gathering, reasoning, findings, and recommendations, readers need to know some background, including the kinds of wastes that are in question, the reasoning behind the re- quirement for deep geologic disposal of these wastes, and the physical and institutional situation of the wastes. Overview of HLW and TRU Waste and the Requirement for Deep Geologic Disposal In 1944, the T-Plant at the Hanford Site (at that time referred to as Site W) began dissolving irradiated uranium fuel from Hanfordâs B- reactor to recover traces of plutonium for the Manhattan Project to use in the first nuclear weapons. The liquid waste from the first stages of this and later, more efficient chemical separation processes consisted of an acidic solution containing radioactive fission products and most of the 5 actinides produced in the reactor fuel. The waste was, in most cases, chemically neutralized with sodium hydroxide and stored in large, un- 6 derground tanks made of carbon steel. Decay of the radioactive constitu- ents generated large amounts of heat and radiation, which required that the storage tanks contain structures to enable active cooling of the waste to prevent self-boiling and made handling this material extremely haz- ardous (Gephart, 2003). In the 1950s, the Atomic Energy Commission (a predecessor of DOE) referred to this waste as âhigh-level radioactive wasteâ and lumped all other radioactive wastes into two other categories: medium- or intermediate-level waste and low-level waste. These latter two categories were both disposed at or near the surface (NCRP, 2002). Thus, HLW was originally defined primarily by its source and that ap- proach has not changed (U.S. Code, Title 42, Section 10101): High-Level Waste is (A) the highly radioactive waste material resulting from the reprocessing of spent nuclear fuel, including liquid waste produced directly in reprocessing and any solid material derived from such liquid waste that con- tains fission products in sufficient concentrations; and (B) other highly radioac- 5 For a solvent extraction separation process, this liquid remainder is called the raffi- nate; thus, the term âfirst-cycle raffinateâ appears in some documents. 6 Tanks at INEEL and a tank at the West Valley Demonstration Project were made of stainless steel, and the wastes in these tanks were not neutralized for storage.
INTRODUCTION 21 tive material that the Commission, consistent with existing law, determines by 7 rule to require permanent isolation. Until the middle 1970s, it was planned that spent fuel from power re- actors would be reprocessed in relatively modern facilities to yield HLW which, like the waste from the nuclear weapons program, would pose major challenges in waste management and disposal. For several reasons, most notably economic and political, reprocessing of civilian spent nu- clear fuel was realized on only a small scale, halted in the 1970s, and has 8 not been pursued in the United States since then. The Atomic Energy Commission considered several possible ways of disposing of highly radioactive liquid waste. In 1957, the National Research Councilâs (NRCâs) Committee on Waste Disposal (a predeces- sor of the current Board on Radioactive Waste Management) issued a report requested by the Atomic Energy Commission recommending that high-level radioactive waste be disposed of in a deep geologic formations (NRC, 1957). The report highlighted salt formations as looking particu- larly promising. Deep geologic disposal has the advantage of isolating radioactive waste in an environment that is designed to require little ongoing active maintenance. Because some radioactive waste will remain hazardous for millennia, it is important to dispose of it in a way that protects future generations from harm in the event that institutional knowledge of its whereabouts and hazards is lost. During the first 300-500 years after HLW is generated, the radioactivity, the heat generation, and radiation emitted by the waste are dominated by relatively short-lived isotopes, such as strontium-90 and cesium-137. Thereafter, as these shorter-lived radioisotopes decay, the actinides (uranium, neptunium, plutonium, and 9 americium) and long-lived fission products (technetium-99 and iodine- 129) remain and dominate the hazard. 7 A provision added in the FY 2005 Defense Authorization Bill modifies this defini- tion to some extent. See discussion of recent legal and regulatory developments that af- fect TRU and HLW disposal later in Section 1.2 of this report. 8 For descriptions of the history of the DOE sites and activities, see DOE (1995, 1997). Waste from reprocessing of civilian nuclear reactor fuel is not addressed in this report, but for two perspectives on the decision not to continue commercial reprocessing in the United States see http://www.pbs.org/wgbh/pages/frontline/shows/reaction/ readings/us.html. 9 All TRU isotopes (isotopes with atomic number greater than 92) are radioactive and many are alpha emitters, which are particularly hazardous when inhaled or ingested. Every TRU isotope is long-lived or has a long-lived decay product. This means that after
22 RISK AND DECISIONS ABOUT TRU AND HLW In the 1960s, the Atomic Energy Commission tried to develop a dis- posal site in salt formations near Lyons, Kansas. The effort fell apart when technical and political difficulties with the site became evident. Attention then shifted toward sites in the Delaware Basin, a large geo- logic formation covering much of the Southwestern United States. In particular, a site near Carlsbad, New Mexico, was selected for extensive study. This site was a candidate to host a HLW repository, but later was selected to dispose of TRU waste. By 1980, the nation still had no formal strategy for developing dis- posal capacity for spent nuclear fuel and HLW. In 1982, however, Con- gress enacted the Nuclear Waste Policy Act (NWPA). The NWPA codified the source-based definition of HLW and officially adopted the deep geologic repository concept as the nationâs long-term strategy for 10 HLW disposal. Yucca Mountain in Nevada was designated by the Nu- clear Waste Policy Amendments Act of 1987 as the only site to undergo characterization to determine its suitability to host a repository for com- mercial spent nuclear fuel and defense high-level waste. Congress also allocated the space available at this repository between the spent nuclear fuel coming from U.S. nuclear power plants and defense HLW (i.e., spent nuclear fuel and HLW produced by DOE facilities). In 2002, the secretary of energy recommended that the President find that the Yucca Mountain site is suitable for development of a deep geologic repository. The President did so and Congress overrode the veto exercised by the State of Nevada, as authorized in NWPA. DOE has said it plans to sub- mit a license application to the Nuclear Regulatory Commission for con- struction of a repository at Yucca Mountain. The U.S. Court of Appeals for the D.C. Circuit invalidated the radiation standards that govern li- censing of a HLW repository at Yucca Mountain. At the time of the 1957 NRC report, management of radioactive waste from weapons production was undergoing some changes. The bismuth phosphate process used by the first chemical separation plants was inefficient and generated large volumes of waste. Because tank space was in short supply, from the late 1940s the operators at Hanford pumped liquid waste through a cascade of tanks, allowing settling and precipitation to remove insoluble components of the waste. These solids, which remained in the bottoms of the tanks, contained most of the acti- a relatively brief period during which the initial shorter-lived isotopes decay, the hazard posed by TRU waste does not diminish substantially for millennia. 10 Nuclear Waste Policy Act of 1982, Public Law No. 97-425, 96 Stat. 2201, January 7, 1983.
INTRODUCTION 23 nides and strontium from the waste, like the sludge found in the tanks today. The liquid supernate, which contained the soluble constituents (notably tritium, technetium, iodine, and cesium) was discharged to the soil. The practice of cascading the wastes was discontinued in the 1950s, but the supernate was still discharged to the soil after most of the cesium had been removed by precipitation by adding potassium ferrocyanide (Gephart, 2003; NRC, 2001a). Like these liquid wastes, until 1970 those solid wastes deemed other than high-level waste (i.e., not the solids in the HLW tanks, but all other solid radioactive wastes) were disposed of by dumping them in near-surface pits and trenches. In 1969, the Atomic Energy Commission General Managerâs Task Force on Operation Waste issued an immediate action directive calling for segregation and retrievable storage of plutonium and solid waste con- taminated with transuranic material above 10 nanocuries per gram (nCi/g) from waste destined for shallow land burial because it concluded that the practice of shallow land burial was unsuitable for TRU waste 11 (DOE, 1988). In 1973, the commission issued Chapter 0511 of the Atomic Energy Commission Manual, which defined TRU waste as waste that is âcontaminated with certain alpha-emitting radionuclides of long half-life and high specific radiotoxicity to greater than 10 nanocuries per gramâ (Smith, 1982). That definition was revised when DOE issued Or- der 5820.1, Management of Transuranic Contaminated Material, in 1982: âTRU-contaminated material includes alpha-emitting radionuclides of atomic number greater than 92 and half-life greater than 20 years in a concentration greater than 100 nCi/g (DOE, 2001; WIPPLWA, 1992). The boundary of TRU was raised from 10 to 100 nanocuries per gram (nCi/g) based on the recommendations of the Proceedings of Alpha Con- taminated Waste Management Workshop (ORNL, 1982). The recom- mendations were based on considerations of risk and practicality presented in numerous technical papers. The Waste Isolation Pilot Plant Land Withdrawal Act (Public Law 102-579) provides the current defini- tion: Transuranic Waste is waste containing more than 100 nanocuries of alpha- emitting transuranic isotopes [atomic number greater than 92] per gram of waste, with half-lives greater than 20 years, except for: ⢠High-level radioactive waste; 11 The implementation period for this notice extended into 1970, so the âeffective dateâ of the directive is often cited as 1970 (Perge, 1982).
24 RISK AND DECISIONS ABOUT TRU AND HLW ⢠Waste that the Secretary [of Energy] has determined, with the concurrence of the Administrator [of the Environmental Protection Agency], does not need the degree of isolation required by the disposal regulations; or ⢠Waste that the Nuclear Regulatory Commission has approved for disposal on a case-by-case basis in accordance with part 61 of title 10, Code of Federal Regulations. Most of the volume of transuranic waste is equipment and clothing contaminated with transuranic elements (such as plutonium) during the design and production of nuclear weapons. However, some of the wastes (e.g., sludge from cleanup) have much higher concentrations of pluto- nium. TRU waste is subclassified as âcontact handledâ or âremote han- dledâ based on the penetrating radiation it emits: these designations are most often used as a basis for defining operational requirements in the facility generating the waste, transportation, or disposal operations, al- though both contact-handled TRU and remote-handled TRU require dis- position in a deep geologic repository, by law. Distinctions are also made between TRU waste that is of civilian origin and TRU waste that is of defense origin based on the purpose of the program that generated the waste. This is a political distinction made important because Congress decided to develop a repository for the disposal of TRU waste that is of defense origin. As noted above, a site near Carlsbad, New Mexico, was under inves- tigation as a potential deep geologic repository. The Waste Isolation Pilot Plant (WIPP) began as a tunnel in bedded salt nearly 700 meters below the earthâs surface. Investigations continued for more than 20 years and Congress passed the Waste Isolation Pilot Plant Land Withdrawal Act in 1992 to create a formal mechanism for DOE to seek permission to oper- ate a repository there for disposal of defense-origin TRU waste. DOE constructed a mined repository and applied to U.S. EPA for certification 12 of the application. U.S. EPA certified WIPP, and the facility began ac- cepting TRU waste for geologic disposal in 1999. Following the 1969 directive, most DOE sites began storing TRU waste by stacking the waste containers (mostly barrels and boxes) on the ground and covering them with soil. Many of these âretrievably buriedâ packages are in poor condition now, but DOE is committed to retrieving them for disposal in a deep geologic repository and storage practices im- 12 Certification is the term used for the approval process created in the WIPP Land Withdrawal Act. It is analogous to a license-application approval used in other regulatory processes.
INTRODUCTION 25 proved so the challenge of working with corroded or disintegrating pack- ages does not extend to all TRU. In addition to retrievable TRU waste, large volumes of waste that meet the concentration specifications in the TRU definition were dis- posed of in trenches and pits prior to the 1969 directive. This âburied TRUâ waste is regulated under the Comprehensive Environmental Re- sponse, Compensation, and Liability Act (CERCLA, see 40 CFR Parts 300-374 for the regulations), the Resource Conservation and Recovery Act (RCRA), or applicable state statutes because it is an uncontrolled release of hazardous substances into the environment. DOE currently manages buried TRU on a site-by-site basis with local regulatory author- ity, like it does environmental restoration issues at the sites. The CER- CLA process illustrates how some decisions about buried TRU are made. Within the context of the CERCLA process, a remedial solution to remove, reduce, and/or manage the contamination can be judged as a potentially âacceptable solutionâ through the application of nine evalua- tion criteria, as follows: 1. overall protection of human health and the environment; 2. compliance with applicable or relevant and appropriate require- ments (ARARs) unless a waiver is granted; 3. long term effectiveness and permanence; 4. reduction of toxicity, mobility, or volume through the use of treatment; 5. short term effectiveness; 6. implementability; 7. cost; 8. state acceptance; and 9. community acceptance. CERCLA calls for remedial actions at hazardous waste sites that (1) satisfy standards from other federal and state environmental programs that are âapplicable or relevant and appropriate under the circumstances (ARARs)â and (2) are protective of human health and the environment (U.S. EPA, 1989). Qualitative preferences for remedies that provide reli- able and long term protection are stated, but numerical standards (allow- able content of contaminant in a specific volume of environmental media) and acceptable or allowable risk limits are not listed. In addition, CERCLA provides no paradigm to consider its nine balancing criteria in an explicit and consistent manner. See Section 5.4 for more discussion of DOE risk assessment processes, such as CERCLA.
26 RISK AND DECISIONS ABOUT TRU AND HLW The geologic-disposal requirement for TRU waste is an ARAR under CERCLA. CERCLA §121(d) and its implementing regulations (the Na- tional Contingency Plan) provide exceptions for meeting ARARs, in- cluding a process for seeking ARARs exemptions (see Sidebar 3.3). Depending on what action is selected in the record of decision at each of these disposal sites, buried TRU waste may be exhumed, characterized, treated, and shipped for disposal at WIPP, or other remedial actions may be taken. In selecting a remedy under CERCLA, the long-term effective- ness of the remedy must be considered and there is a preference for per- manent solutions. Some see these provisions as indicating a default preference for retrieval and deep geologic disposal of buried TRU waste. Thus, the disposition path for nearly all HLW and TRU waste is pre- sumed to be deep geologic disposal, where disposal refers to emplace- ment with no intent to retrieve. Since the publication of the 1957 National Research Council report, other options for dealing with TRU and HLW have been considered, including (1) extraterrestrial disposal, (2) subseabed and deep borehole disposal, and (3) partitioning and 13 transmutation, which is now being explored by several nations. Al- though these alternative methods could hold promise for future genera- tions, emplacement in a deep geologic repository now remains the best prospect for permanent isolation. Another NRC committee recently reaf- firmed this recommendation (NRC, 2001b), and disposition in a deep geologic repository remains the preferred option for disposing of long- 14 lived radioactive waste produced by defense facilities, nuclear power plants and other sources (NRC, 1990, 2001b). 13 Schemes for partitioning and transmutation involve chemical separation of long- lived constituents of spent nuclear fuel or HLW and irradiation of these constituents in a critical or subcritical nuclear reactor. Such schemes can reduce the quantity of long-lived radioactivity in the waste, although some remains and long-lived isolation is still required (see, e.g., NRC, 1995a, and NRC, 2001b pp. 119â124). 14 Long-lived radioactive waste is radioactive waste that requires isolation from the biosphere for thousands of years or more.
INTRODUCTION 27 Summary of Waste Inventories and Current Expected Disposition Paths 3 15 DOE estimates that it has approximately 340,000 m of HLW, which consists mostly of mixed fission products containing approxi- 16 mately 835 million curies (MCi) of radioactivity. DOE also estimates 3 that it has at least 287,000 m of retrievably stored and buried TRU waste containing more than 3.1 MCi of TRU radioactivity, including some fis- sion and activation products (DOE, 2001) at its sites. High-level waste includes small volumes of intensely radioactive material and large quan- tities of nonradioactive chemicals mixed with various radionuclides (e.g., saltcake containing sodium nitrate and cesium-137). The TRU waste in- cludes some waste that requires remote handling to protect workers and also includes much less radioactive equipment, rags, and protective clothing near the 100 nCi/g contamination limit that defines TRU waste. The buried TRU waste is highly heterogeneous and was generally dumped into pits and trenches, with no effort made to keep waste pack- ages intact and little effort expended on record keeping. For these rea- sons and because of the hazards that could be incurred by digging into it, characterization of these wastes has been difficult. DOE estimates that the total volume of buried TRU waste in near-surface pits and trenches is 3 approximately 126,000 m containing about 397,000 curies (Ci) of TRU 17 3 radioactivity. Another 11,000 m containing 10,000 Ci is disposed of at 18 greater depths. Soils contaminated such that they are considered TRU 3 waste (found mostly at Hanford) comprise an additional 32,000 m con- taining about 33,000 Ci (DOE, 2000). The volumes of buried TRU are not included in the wastes planned for disposal at WIPP. 15 This volume of HLW would occupy nearly 9400 standard tanker trucks, or about one and one-half large oil tanker ships. 16 These numbers do not include spent nuclear fuel, which is outside the scope of this study. The total radioactivity, obtained from site personnel during this study, is inconsis- tent with that found in DOE (2001), which reports larger total radioactivity in HLW at SRS and INEEL than any other DOE source the committee found. 17 This is the projected value correcting for decay through 2006 (DOE, 2000). 18 These wastes were disposed of by injecting waste grout into cracks in shale forma- tions 250-360 meters below the surface (a method called hydrofracture) at the Oak Ridge Reservation from 1963 to 1984, by placement in roughly 20-meter-deep shafts (for post- 1971 remote-handled TRU) at the Los Alamos National Laboratory; and by placement in thirteen 40-meter-deep boreholes at the Nevada Test Site (for classified TRU waste) (DOE, 1998a, 2001; SNL, 2004). âGreater depthsâ is intermediate depth.
28 RISK AND DECISIONS ABOUT TRU AND HLW Deep geologic disposal is the only contemplated ultimate disposition path for several waste streams. These include: ⢠HLW already immobilized in approximately 1750 canisters of HLW glass stored at SRS and the 275 canisters stored at the West Valley site, ⢠the high-actinide-content waste streams from processing the re- 3 maining 330,000 m (about 91 million gallons) of HLW at Han- ford and SRS (Hintze, 2004; Wiegman, 2004), and, 3 ⢠nearly all of the approximately 115,000 m of retrievably stored TRU waste across the DOE complex. DOE has been evaluating alternative disposition approaches for a di- verse set of waste streams including lower-activity waste streams from processing HLW (e.g., sodium-bearing waste at INEEL, lower-activity saltcake at SRS, and low-activity waste and supplemental treatment waste at Hanford), âheelsâ (liquids from tank washing and some original waste solids remaining in tanks after substantial retrieval) in more than 200 HLW tanks; 131 MCi of encapsulated cesium and strontium sources separated from Hanfordâs HLW (DOE, 2002a); tens of curies of corro- sion products from spent fuel stored in the K Basins at Hanford; buried TRU waste (potentially more than tens of thousands of cubic meters) about which DOE and states disagree on ultimate disposition; and TRU waste on which DOE says the WIPP waste acceptance criteria impose major burdens. Some of these are described in greater detail in Chapter 2. The foregoing discussion has focused on the waste and how it will be managed, but the wastes are part of the DOE cleanup program and so are handled in the context of the overall cleanup at the sites. Each of the three sites visited by the committee has a federal facility agreement (FFA) that defines what DOEâs cleanup efforts must accomplish, when it must accomplish each step, and in many cases, the means by which the accomplishments are to be achieved (Hanford FFA, 2003; INEEL FFA, 1991; SRS FFA, 1993). These compliance agreements are legally en- forceable. Violations of these agreements have occurred and led to fines being imposed on DOE by the state. The compliance agreements involve at least three parties: DOE, the siteâs regional EPA office, and the host state, which is usually repre- sented by its department of environmental compliance or equivalent. Be- cause DOE is self-regulating concerning the radionuclide content of the
INTRODUCTION 29 TRU and HLW waste streams, these agreements focus on lawsâ CERCLA, the RCRA, the Safe Drinking Water Actâthat apply to cer- tain radioactive wastes but were designed for other environmental haz- 19 ards. In most cases the agreements do not cover all details of long-term ef- forts, such as cleanup of HLW tanks and buried TRU waste. Instead, the agreements are fairly prescriptive for the next few or several years and then identify only general directions or simply the need to make a deci- sion at some point in the future. An example of this is the Hanford agreement, which has milestones and other details including minimum removal requirements for tank wastes, but does not yet specify how or when tanks will be closed once retrieval is completed. To allow for such evolution, the agreements are âliving documentsâ that can be modified to accommodate progress and changing circumstances. The evolving na- ture of these agreements is a practical necessity given that it would be impossible to know everything in sufficient detail at the outset to pre- scribe actions over the life of a multiple-decade project. The committee was told that the Hanford agreement had been modified hundreds of 20 times. Significantly, all three parties must agree to make any change in the agreement or even to enter discussion of making changes in the agreement before these events can occur. Recent Legal and Regulatory Developments That Affect TRU and HLW Disposal In the 1980s, DOE determined that immobilizing all of the HLW in the complex without some kind of separations would send enormous numbers of canisters of HLW to the HLW repository. To reduce the number of canisters destined for a repository (see Chapter 2 for more details), DOE developed plans to chemically process or treat HLW to 19 SRS operates under a wastewater permit from the South Carolina Department of Health and Environmental Quality. 20 â Since it was first approved on May 15, 1989 there have been 428 change requests approved to the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement). Each of these approved change requests can consist of many different types of changes. For example a change request can consist of a minor modification such as the update of a personâs title or it can be a major modification to the milestones controlling a large scope of work. Many of the approved change requests have added milestones (addi- tional work scope) which has increased the number of enforceable milestones from the 161 original milestones to 1,188 todayâ (Morrison, 2004).
30 RISK AND DECISIONS ABOUT TRU AND HLW separate most of the long-lived and highly radioactive constituents into a high-activity waste stream leaving only low concentrations of radioactiv- ity in a large volume of low-activity waste. The high-activity waste stream would still be considered HLW and would require disposal in a deep geologic repository. The remaining low-activity waste stream would be much less hazardous and DOE reasoned that it would not re- quire the isolation required for HLW. To address the various waste streams that emerged from this treat- ment of HLW, in 1999 DOE issued Order 435.1 which set out a proce- dure for determining some waste to be âincidental to reprocessingâ and therefore classified and managed either as low-level waste or transuranic 21 waste (see Sidebar 1.3). As low-level waste, the material could be dis- posed of in a near-surface facility onsite at the DOE facilities where the wastes were generated. The first official document referring to waste incidental to reprocess- ing appears to be a 1969 Atomic Energy Commission Notice of Proposed Rulemaking on regulations for nuclear fuel reprocessing plants. The Fi- nal Rule in 1970, Appendix F to 10 CFR Part 50, dropped the incidental waste description, and was the first regulation to define liquid HLW as âthose aqueous wastes resulting from the operation of the first cycle sol- vent extraction system, or equivalent, and the concentrated wastes from subsequent extraction cyclesâ¦.â In the late 1980s and early 1990s, DOE sought U.S. NRC concurrence on how DOE proposed to determine when HLW has been retrieved to a point sufficient that residues in tanks, pipes, and equipment, and the waste in the separated low-activity streams could be classified as something other than HLW (Rizzo, 1989; Bernero, 1989). U.S. NRC denied a petition by the states of Oregon and Washing- ton which requested that U.S. NRC assert authority over HLW classifica- tion determinations and âestablish a procedural framework and substantive standards by which the Commission would determine whether reprocessing waste...is HLWâ (Bernero, 1993). U.S. NRC in- stead found that the principles for waste classification are well estab- lished,â endorsing the criteria DOE later used in Order 435.1. 21 DOE regulates itself on matters covered by the Atomic Energy Act (most relevant here are nuclear materials and radioactive waste). Similar to regulations at U.S. NRC and U.S. EPA, DOE orders are the rules that govern DOE facilities on these matters. DOE Order 435.1 is titled âRadioactive Waste Managementâ (see www.directives.doe.gov). A prior DOE order with the same title, DOE Order 5820.2A, did not contain the provisions for determining waste to be incidental to reprocessing.
INTRODUCTION 31 Sidebar 1.3: Waste Incidental to Reprocessing DOE Order 435.1 states: [wastes incidental to reprocessing] may include, but are not limited to, spent nuclear fuel reprocessing plant wastes that: (a) Will be managed as low-level waste and meet the following criteria: 1. Have been processed, or will be processed, to remove key radionu- clides to the maximum extent that is technically and economically prac- tical; and 2. Will be managed to meet safety requirements comparable to the per- formance objectives set out in 10 CFR Part 61, Subpart C, Performance Objectives; and 3. Are to be managed, pursuant to DOEâs authority under the Atomic En- ergy Act of 1954, as amended, and in accordance with the provisions of Chapter IV of this Manual, provided the waste will be incorporated in a solid physical form at a concentration that does not exceed the applica- ble concentration limits for Class C low-level waste as set out in 10 CFR 61.55, Waste Classification; or will meet alternative II-14 DOE G 435.1- 1 7-09-99 Chapter II High-Level Waste Requirements for waste classifi- cation and characterization as DOE may authorize. (b) Will be managed as transuranic waste and meet the following criteria: 1. Have been processed, or will be processed, to remove key radionu- clides to the maximum extent that is technically and economically prac- tical; and 2. Will be incorporated in a solid physical form and meet alternative re- quirements for waste classification and characteristics, as DOE may au- thorize; and 3. Are managed pursuant to DOEâs authority under the Atomic Energy Act of 1954, as amended, in accordance with the provisions of Chapter III of this Manual, as appropriate. The implementation of DOE Order 435.1 was challenged in federal district court in 2001 on the grounds that, contrary to law, the order grants DOE the authority to reclassify waste arbitrarily and unilaterally (NRDC v. Abraham, 2002, Case 01-413). The court reviewed the defini- tion of HLW in the NWPA and DOEâs interpretation of the definition. In its ruling, the court stated that âDOEâs Order 435.1 directly conflicts with NWPAâs definition of HLW. NWPAâs definition pays no heed to technical or economic constraints in waste treatment. Moreover, NWPA
32 RISK AND DECISIONS ABOUT TRU AND HLW does not delegate to DOE the authority to establish alternative require- 22 ments for solid waste.â Following the Idaho court decision that rejected DOEâs Order 435.1 process for exempting wastes, there were no regula- tory exceptions to the characterization of tank wastes as HLW. In United States of America v. Dirk Kempthorne, Governor of Idaho (USA v. Kempthorne, Case No. 91-054-S-FJL, March 31, 2003), a differ- ent judge in the U.S. district court in Idaho ruled that a 1995 settlement agreement between the State of Idaho and DOE requires that DOE re- move all TRU waste, including buried TRU waste, from the INEEL by the end of the year 2018. DOE is also seeking to reverse this ruling. DOE appealed both of these rulings to the U.S. Court of Appeals for the Ninth Circuit. In the first case, DOE also asked Congress to restate the definition of HLW consistent with DOEâs interpretation in Order 435.1 by amending the NWPA (Abraham, 2003). DOE is also negotiat- ing with the States of Idaho, Washington, South Carolina, and New Mex- ico on HLW issues, seeking to ease requirements under the federal facility agreements that DOE has signed with U.S. EPA and the states. On October 8, 2004, the U.S. House and Senate Armed Services Committees conferees agreed on the contents of the National Defense Authorization Act of 2005, Section 3116, which concerns waste inciden- tal to reprocessing. President Bush signed the act into law on October 28, 2004. Sidebar 1.4 contains the text of that section. In summary, the legis- lation qualifies the definition of HLW by stating that reprocessing waste that meets certain criteria (i.e., has had highly radioactive radionuclides removed to the maximum extent practical; does not require permanent isolation in a deep geologic repository; and performance objectives for low-level waste) is not HLW. DOE is to make such determinations in consultation with the U.S. NRC, and disposal must be in accord with a 22 The U.S. district court in Idaho ruled that the NWPA grants DOE no discretion in the question of disposal method. It further held that the statutory definition admits of no exemptions from HLW for liquid reprocessing waste. Solid waste derived from such liquid waste, on the other hand, need not be classified as HLW if it is does not contain âsufficient concentrationsâ of radionuclides. However, the court invalidated DOEâs method for reclassification of wastes for three reasons. First, it applied to both liquids and derived solids, and liquids do not have exemptions. Second, the statutory language refers only to concentrations of radionuclides as the proper criterion for reclassification, and DOEâs internal regulations included cost and technical feasibility as criteria. Third, the DOE regulations did not meaningfully limit its discretion to reclassify such wastes. The court was neither presented with, nor did it address the possibility of a general de minimis exemption for disposal of minute amounts of liquid or solid HLW (NRDC v. Abraham. 2003. Memorandum Decision. Civ. No. 01-0413-S-BLW. U.S. District Court for the District of Idaho. 271 F. Supp. 2d 1260. July 2, 2003).
INTRODUCTION 33 closure plan approved by the host state. Section 3116 of the act applies to the States of South Carolina and Idaho only. Washington, Oregon, and other states aside from Idaho and South Carolina explicitly are not sub- ject to this provision of the law. Finally, the Court of Appeals for the Ninth Circuit ruled on both of DOE's appeals. On November 5, 2004, a three-judge panel overturned the District court's summary judgment in the HLW case because the case was not ripe, i.e., DOE had not yet applied Order 435.1 to a particular situation (Case No. 03-35711, D.C. Number CV-01-00413-BLW). The court there- fore could not address the merits of the case. On December 3, 2004, the same panel of judges remanded the decision on INEEL's buried TRU waste back to the District court, as DOE requested, to consider extrinsic evidence central to DOE's argument (Case No. 03-35470, D.C. Nos. CV-91-00054- HLR/EJL and CV-91-00035-HLR/EJL). This committee has no authority to determine matters of law and of- fers no opinion on the merits of the litigation or other actions taken to change or preserve the current legal interpretation of HLW or to deter- mine final disposition of the buried TRU waste at INEEL. The foregoing information is provided to illustrate the events surrounding DOEâs re- quest for review of the risk-based disposition of HLW and TRU waste and the committeeâs deliberations. As described in Chapter 3, the com- mittee contends that the approach advocated in this report should be pur- sued under the new law, regardless of the outcome of the litigation. Even if DOEâs existing exemption process is found legally valid, its substance and procedure would be improved by the process set out herein. Sidebar 1.4: The Ronald W. Reagan National Defense Authorization Act for Fiscal Year 2005 Section 3116. Defense Site Acceleration Completion. (a) IN GENERAL.âNotwithstanding the provisions of the Nuclear Waste Policy Act of 1982, the requirements of section 202 of the Energy Reorganization Act of 1974, and other laws that define classes of radioactive waste, with respect to mate- rial stored at a Department of Energy site at which activities are regulated by a cov- ered State pursuant to approved closure plans or permits issued by the State, the term âhigh-level radioactive wasteâ does not include radioactive waste resulting from the reprocessing of spent nuclear fuel that the Secretary of Energy (in this section referred to as the âSecretaryâ), in consultation with the Nuclear Regulatory Commis- sion (in this section referred to as the âCommissionâ), determinesâ
34 RISK AND DECISIONS ABOUT TRU AND HLW (1) does not require permanent isolation in a deep geologic repository for spent fuel or high-level radioactive waste; (2) has had highly radioactive radionuclides removed to the maximum extent practical; and (3) (A) does not exceed concentration limits for Class C low-level waste as set out in section 61.55 of title 10, Code of Federal Regulations, and will be disposed ofâ (i) in compliance with the performance objectives set out in subpart of part 61 of title 10, Code of Federal Regulations; and (ii) pursuant to a State-approved closure plan or State-issued permit, authority for the approval or issuance of which is conferred on the State outside of this section; or (B) exceeds concentration limits for Class C low-level waste as set out in section 61.55 of title 10, Code of Federal Regulations, but will be dis- posed ofâ (i) in compliance with the performance objectives set out in subpart C of part 61 of title 10, Code of Federal Regulations; (ii) pursuant to a State-approved closure plan or State-issued permit, authority for the approval or issuance of which is conferred on the State outside of this section; and (iii) pursuant to plans developed by the Secretary in consultation with the Commission. (b) MONITORING BY NUCLEAR REGULATORY COMMISSION.â (1) The Commission shall, in coordination with the covered State, monitor dis- posal actions taken by the Department of Energy pursuant to subparagraphs (A) and (B) of subsection (a)(3) for the purpose of assessing compliance with the performance objectives set out in subpart C of part 61 of title 10, Code of Federal Regulations. (2) If the Commission considers any disposal actions taken by the Department of Energy pursuant to those subparagraphs to be not in compliance with those performance objectives, the Commission shall, as soon as practicable after discovery of the noncompliant conditions, inform the Department of Energy, the covered State, and the following congressional committees: (A) The Committee on Armed Services, the Committee on Energy and Com- merce, and the Committee on Appropriations of the House of Representa- tives. (B) The Committee on Armed Services, the Committee on Energy and Natu- ral Resources, the Committee on Environment and Public Works, and the Committee on Appropriations of the Senate. (3) For fiscal year 2005, the Secretary shall, from amounts available for defense site acceleration completion, reimburse the Commission for all expenses, in-
INTRODUCTION 35 cluding salaries, that the Commission incurs as a result of performance under subsection (a) and this subsection for fiscal year 2005. The Department of Energy and the Commission may enter into an interagency agreement that specifies the method of reimbursement. Amounts received by the Commis- sion for performance under subsection (a) and this subsection may be re- tained and used for salaries and expenses associated with those activities, notwithstanding section 3302 of title 31, United States Code, and shall remain available until expended. (4) For fiscal years after 2005, the Commission shall include in the budget justi- fication materials submitted to Congress in support of the Commission budget for that fiscal year (as submitted with the budget of the President un- der section 1105(a) of title 31, United States Code) the amounts required, not offset by revenues, for performance under subsection (a) and this sub- section. (c) INAPPLICABILITY TO CERTAIN MATERIALS.âSubsection (a) shall not apply to any material otherwise covered by that subsection that is transported from the covered State. (d) COVERED STATES.âFor purposes of this section, the following States are covered States: (1) The State of South Carolina. (2) The State of Idaho. (e) CONSTRUCTION.â (1) Nothing in this section shall impair, alter, or modify the full implementation of any Federal Facility Agreement and Consent Order or other applicable con- sent decree for a Department of Energy site. (2) Nothing in this section establishes any precedent or is binding on the State of Washington, the State of Oregon, or any other State not covered by sub- section (d) for the management, storage, treatment, and disposition of radio- active and hazardous materials. (3) Nothing in this section amends the definition of âtransuranic wasteâ or regu- lations for repository disposal of transuranic waste pursuant to the Waste Isolation Pilot Plant Land Withdrawal Act or part 191 of title 40, Code of Federal Regulations. (4) Nothing in this section shall be construed to affect in any way the obligations of the Department of Energy to comply with section 4306A of the Atomic En- ergy Defense Act (50 U.S.C. 2567). (5) Nothing in this section amends the West Valley Demonstration Act (42 U.S.C. 2121a note).
36 RISK AND DECISIONS ABOUT TRU AND HLW (f) JUDICIAL REVIEW.âJudicial review shall be available in accordance with Chapter 7 of title 5, United States Code, for the following: (1) Any determination made by the Secretary or any other agency action taken by the Secretary pursuant to this section. (2) Any failure of the Commission to carry out its responsibilities under subsec- tion (b).
