Fig. 1. Volume of commercial LLW
received at disposal sites (based on data from National Low-Level Waste
Program)
Jas S. Devgun, Ph.D.
Delta Environmental Corporation
1018 Rain Tree Drive
Bolingbrook, IL 60440
Robert W. Peters, Ph.D.
Argonne National Laboratory
9700 South Cass Avenue
Argonne, IL 60439
ABSTRACT
It has been sixteen years since the enactment of Low-Level Radioactive Waste Policy Act (LLRWPA) in 1980 which shifted responsibility for the disposal of low-level radioactive waste (LLW) to the states. During this period, the LLW generation, processing and disposal have undergone dramatic changes. While the future of nuclear power generation has remained in a stalemate, there has been a major shift in the nuclear power industry as far as the generation and processing of LLW are concerned. Other generation sources of LLW have also undergone major changes. The waste volumes for disposal have decreased significantly during the past sixteen years, with more drastic changes occurring during the last past six years. The progress on development of new disposal capacity remains stalled, and the continued availability of current disposal sites remains uncertain. It would appear that there is a definite need for further disposal capacity development. However, no new disposal sites have opened yet and it is now evident that disposal facility development is more complex, time-consuming, and controversial than originally anticipated. In the meanwhile, escalating disposal costs have become the main driving force leading to a determined effort in LLW source reduction and waste minimization by the nuclear power industry and other generators. The result has been a dramatic reduction in waste volumes to a point where a reconsideration of further disposal capacity development is necessary. Several other considerations complicate the issue.
This paper analyses the issue of disposal capacity development as opposed to the generation volumes in a qualitative fashion. It also summarizes the current status of low-level radioactive waste generation and the status of new disposal facility development efforts by the compacts and unaffiliated states. It should be noted that at this stage a quantitative assessment is not feasible because of a lack of definitive data on planned disposal capacity development and because of the presence of a number of nontechnical issues in the process. Essentially, the plans remain in a flux. It should also be noted that this paper focuses only on the commercial LLW and does not consider the Department of Energy waste or the waste from nation's nuclear defense programs.
INTRODUCTION
During the late 1970s, all of the nations commercial low-level radioactive waste was shipped to three disposal facilities located in Beatty, Nevada; Barnwell, South Carolina; and Richland, Washington. The Low-Level Radioactive Waste Policy Act of 1980 (LLRWPA) made disposal of LLW waste a state responsibility. The Congress encouraged states to form compacts; it further gave compacts the authority to exclude waste from outside the boundaries of the compact region. An interstate compact is a formal agreement between two or more states. This approach was attractive to states because access to a regional disposal facility would be more cost-effective and it could be restricted solely to members of the compact. However, the states could choose to develop facilities on their own and a number of states have remained unaffiliated.
The expectation in the LLRWPA was that new disposal facilities could be operating during the next five years and the legislation specifically provided that after January 1, 1986, the compacts could exclude waste generated outside their compact. By 1983, it was clear that no new facilities would be operational in near future. In December 1985, Congress revisited the issue and enacted the Low-Level Radioactive Waste Policy Amendments Act of 1985 (LLRWPAA). At this time Congress granted consent to the original seven compacts and the LLRWPAA extended the January 1, 1986 deadline by seven years. It also established other milestones, penalties and incentives to encourage development of disposal facilities. Once again, the milestones established by the LLRWPAA proved to be unrealistic and no new disposal sites have opened as yet. The disposal facility development is more complex, time-consuming, and controversial than originally anticipated.
While the development of new disposal sites by the compacts has continued to be stalled or delayed, the nuclear power industry has undergone dramatic changes as far as the generation and processing of LLW are concerned. There have been significant changes in other generation sources of LLW also. The waste volumes for disposal have decreased dramatically during the past sixteen years. A number of factors affect the issue of disposal capacity development versus waste volume generation. These include disposal cost per cubic foot, life cycle estimates of current disposal sites, technologies for waste volume reduction, new facility development costs, siting restrictions, equity considerations, a defacto moratorium on nuclear energy development, public opposition to disposal facilities, and political considerations. The real "wild card" is the decommissioning waste. As several of the nuclear power reactors approach the end of their design life or are decommissioned for other reasons, the quantity of waste generated could increase significantly.
This paper analyses the issue of disposal capacity development as opposed to the generation volumes in a qualitative fashion.
COMMERCIAL LLW CLASSIFICATION AND THE GENERATION SOURCES
It is useful to summarize first the type of waste we are talking about. The commercial LLW covers a wide variety of waste types and activity levels. The classification was established by the U.S. Nuclear Regulatory Commission's Licensing Requirements for Land Disposal of Radioactive Waste (10 CFR Part 61) which also sets forth stability requirements. LLW is divided into four classes based on the concentration of certain short- and long-lived radionuclides. In general, Class A waste, with the lowest concentration of radionuclides, can be disposed of directly without additional stability requirements if it is separated from Class B and Class C waste. Class B and Class C waste forms or containers must maintain their gross physical properties and identity for 300 years. In addition, Class C waste requires disposal at a greater depth than Class A or Class B waste, or intruder barriers with an effective life of 500 years. Disposal of Greater-than-Class C waste, the LLW with the highest radionuclide concentrations, is a federal responsibility assigned to the U.S. Department of Energy. Most of the LLW currently disposed at the commercial disposal sites is Class A waste. During the period from 1991 through 1995, Class A waste comprised about 96% of the commercial LLW that was shipped for disposal, followed by Class B at about 3%, and Class C at 1%.
Among the different sources of commercial LLW, the nuclear power industry generates the largest amount of waste; industrial, academic, government, and medical sources account for the rest. During the period from 1991 through 1995, the nuclear power industry accounted for nearly 50% of the waste volume and above 80% of the activity. The LLW (dry active waste and wet solids) generated by nuclear power reactors contains the following key radionuclides: Fe-55, Co-60, Ni-63, Cs-134, Cs-137, Sr-90, I-129, C-14, H-3, Cr-51, Mn-54, and Tc-99. The dry active waste generally consists of contaminated protective clothing, plastics, paper, cloth, adsorbent materials, metals, wood, tools, concrete, and other miscellaneous items. Wet waste consists of resins filters, evaporator bottoms, and sludges. Wet waste can be dewatered, after which dry waste processing can be applied.
The key radionuclides in the waste originating from industrial sources include: H-3, Co-60, Cs-137, Cs-134, S-35, P-32, Th-232, Th-230, U-238, Ir-192, and Sr-90. Government-generated waste typically contains Sr-90, Co-60, Fe-55, U-238, Mn-54, Ni-63, Co-58, Ra-226, C-14, H-3, U-235, Ni-59, Tc-99, Am-241, I-125, and Cs-137. The waste from academia generally contains H-3, Co-60, I-129, Pm-147, S-35, Cr-51, P-32, C-14, I-131, I-125, Ca-45, Ni-63, Ra-226, Co-57, and K-40, while the medical waste may include P-32, C-14, S-35, Co-57, Ba-133, I-125, Ca-45, Cr-51, Tc-99, and H-3.
Most of the activity in commercial LLW comes from short-lived radionuclides. A 1993 U.S. Nuclear Regulatory Commission study found that during 1987, 1988, and 1989, 96% of the activity disposed at Barnwell, 99% of the activity disposed at Beatty, and 98% of the activity disposed at Richland consisted of isotopes with a half-life to 30 years or less. At least 80% of the activity disposed at each of the sites was attributable to three radionuclides: Fe-55 (2.7 year half-life), Co-60 (5.3 year half-life), and H-3 (12.3 year half life).
During 1995, the states shipping the largest volumes of LLW for disposal were: South Carolina, Tennessee, Oregon, Colorado, and Washington. Based on the total activity content of the waste shipped, the largest contributing states were: Alabama, Massachusetts, Georgia, Louisiana, and Pennsylvania. It should be noted that these data change from year to year dramatically and they should not be used to draw any general conclusions. For example, the state of New York has sent large volumes for disposal , above 70,000 ft3/year on the average during the years 1991-1994, but in 1995, this volume was only 10,000 ft3. Similarly, the activity was over 170,000 Ci in 1994, and 1950 Ci in 1995.
WASTE VOLUME TRENDS AND THE DISPOSAL STATUS
For more than twenty years, three disposal facilities (located at Barnwell, South Carolina; Beatty, Nevada; and Richland, Washington) accepted almost all the commercial LLW generated in the United State. Historically, Barnwell received the bulk of this waste because of its location relative to the states generating the largest amounts of waste. The Beatty disposal facility was permanently closed on January 1, 1993. Access to the Richland facility is restricted to the 11 states in the Northwest Compact and the Rocky Mountain Compact. Barnwell continues to accept waste from across the country except from North Carolina which has been excluded specifically by South Carolina state legislation.
During the past ten years, the total annual volume of commercial LLW disposed at the three facilities has decreased by two-thirds. In 1984, the total volume of waste disposed was approximately 2,709,000 ft3; by 1993, it had declined to 791,000 ft3. In 1995, the total waste shipped for disposal amounted to 690,000 ft3. However, the total activity of the waste disposed increased dramatically in 1989 and has remained generally high since then. The higher activity may be attributable to the increased age of some nuclear power plants and the need to replace equipment and components with high activity levels. It also may be attributable to LLW generators "cleaning house" of all wastes that could be shipped for disposal before the existing disposal facilities began to restrict access in 1993. Figures 1 and 2 summarize the waste volume and activity changes over the past ten years.
Fig. 1. Volume of commercial LLW
received at disposal sites (based on data from National Low-Level Waste
Program)
Fig. 2. Activity of commercial LLW
received at disposal sites (based on data from National Low-Level Waste Program)
NEW DISPOSAL CAPACITY DEVELOPMENT
Legislative and Other Drivers
As mentioned earlier, through the LLRWPA of 1980, the U.S. Congress encouraged the states to form regional compacts to develop disposal facilities. Assuming that new disposal facilities could be operating by January 1, 1986, the 1980 legislation provided that after January 1, 1986, compacts could restrict use of their disposal facilities by excluding waste generated outside their member states. By 1983, however, it had become clear that no new disposal facilities would be operational by the 1986 milestone because of the time required by the states to negotiate compact agreements and obtain the necessary consent of Congress to the compacts. As a result, the LLRWPAA was passed by Congress in December, 1985, at the same time when Congress granted consent to the original seven compacts comprising 35 states (Central, Central Midwest, Northeast, Northwest, Rocky Mountain, and Southeast Compacts). The LLRWPAA extended the January 1, 1986, deadline by seven years to January 1, 1993, and established a series of milestones, penalties, and incentives to encourage the compacts and states to develop new disposal capacity by the 1993 deadline. This deadline however passed without much progress or penalties.
Disposal cost and the imposition of "out of compact" surcharges are another major factors. Out of compact generators paid as much as $250 per ft3 over the disposal cost of about $60 per ft3. Since South Carolina pulled out of the Southeast compact and is now an unaffiliated state, in place of the above mentioned surcharge, the state imposes a tax of $235 per ft3 over the disposal cost of $65 per ft3. To waste shipper, total disposal cost remains about the same. A steep increase in disposal costs over the past ten years remains one major driver for compacts (and unaffiliated states) to develop their own facilities.
Uncertainty in access to disposal sites remains high. Access to the Richland facility is restricted to the 11 states in the Northwest compact and the Rocky Mountain compact. On July 1, 1994, access to the Barnwell facility was restricted to the eight states in the Southeast compact. However, the political changes in the state leadership, the state reconsidered and opened access to disposal on July 1, 1995. The state has recently pulled out of the Southeast compact. The Barnwell facility can currently accept waste from all states except the 11 states in the Northwest and Rocky Mountain compacts and the state of North Carolina, which has been specifically barred by the state legislation.
Future decommissioning projects in the compact regions and the waste generated from these projects are also major factors. Other factors include transportation issues, and issues related to geographical equity as well as the public and political input.
Current Status of Compacts
It is now 1997 and no new disposal facilities have opened, although four compacts have selected sites and submitted license applications. As of December 1994, ten compacts had been established comprising 45 states. These ten compacts included three new compacts formed since Congress granted consent to the original seven in 1985. The ten compacts are: Appalachian Compact (Delaware, Maryland, Pennsylvania, West Virginia), Central Compact (Arkansas, Kansas, Louisiana, Nebraska, Oklahoma), Central Midwest Compact (Illinois, Kentucky), Midwest compact ( Indiana, Iowa, Minnesota, Missouri, Ohio, Wisconsin), Northwest Compact (Alaska, Hawaii, Idaho, Montana, Oregon, Utah, Washington, Wyoming), Rocky Mountain Compact (Colorado, Nevada, New Mexico), Northeast Compact ( Connecticut, New Jersey), Southeast Compact ( Alabama, Florida, Georgia, Mississippi, North Carolina, Tennessee, Virginia), Southwestern Compact (Arizona, California, North Dakota, South Dakota), Texas Compact ( Maine, Texas, Vermont) .States of Massachusetts, Michigan, New York, New Hampshire, Rhode Island, the District of Columbia, and Puerto Rico remain unaffiliated. Michigan was originally a member of the Midwest Compact, but its membership was revoked in 1991 when it failed to develop a regional disposal facility.
The Northwest compact and the Rocky Mountain compact will continue to use the existing facility at Richland, Washington. Access to the existing facility at Barnwell, South Carolina, is available to all other states except the state of North Carolina. A license application has been submitted for a new regional disposal facility in North Carolina for the Southeast compact. The Southwestern Compact has been granted a license for a new regional disposal facility in California, but it has encountered litigation and land acquisition problems. The Appalachian Compact is nearing the final stage of its siting process in Pennsylvania. The other three remaining compacts have encountered setbacks and started over, or have not advanced. In the unaffiliated states, Massachusetts and New York have enacted legislation and have established siting processes. No activities are underway in the other unaffiliated states, the District of Columbia, or Puerto Rico.
Cumbersome site selection processes, and public and political opposition to those processes, have generally been the biggest impediments to progress in developing new disposal facilities. Other factors have included issues related to funding, enabling legislation, liability, risk, and disposal technology. Even the states that had aggressive siting plans have encountered delays, and legislative milestones have slipped. For example, in the Central Midwest Compact, a volunteer site at Martinsville, Illinois, was proposed for licensing by the state's Department of Nuclear Safety. The site, however, was rejected by a state siting commission after several years of site characterization activities and over $75 million in expenditures. As a result, the state legislature enacted new procedures for siting a disposal facility, and the initial plan to operate a facility in 1995 has been discarded. The only new facility which currently appears close to construction is the Southwestern Compact's proposed site at Ward Valley, California. Again, however, litigation and the delays on the transfer of federal land to California have presently stalled progress.
Cost
One of the biggest driving factor for source reduction and waste minimization has been the steep increases in the disposal cost. In 1975, the charge for disposing Class A waste was only $1 per ft3. By 1985 this charge had risen to $20 per ft3. By 1992, significant surcharges to the base disposal cost raised the cost to above $160 per ft3. With surcharges, disposal of out-of-state waste at Barnwell has been about $300 ft3. Recently, South Carolina pulled out of the Southeast compact and is now an unaffiliated state. Instead of the above mentioned surcharge, the state imposes a tax of $235 per ft3 over the disposal cost of $65 per ft3. To a waste generator, the disposal cost remains high as before.
Effect of Waste Minimization
Steep increases in disposal costs and the uncertainty in access to disposal sites have necessitated implementation of source reduction strategies and extensive use of volume reduction technologies. Concerted efforts by the nuclear utilities in source reduction and volume reduction have led to average volumes of dry active waste (which accounts for 60 to 70% of waste generated by a reactor) that are about one-fifth of the volumes produced only a decade ago. By 1992, an average pressurized water reactor (PWR) generated about 2010 ft3 of LLW annually, and a boiling water reactor (BWR) about 5015 ft3 annually. Similarly, because of the increasing treatment of wet waste, the annual average volume of wet reactor waste has declined to about 990 ft3 for a PWR and about 3990 ft3 for a BWR.
Compaction and supercompaction are the most widely used techniques to reduce volume of compactible solid waste. In addition, baling, shredding, and incineration can be used for solid wastes; incineration can especially provide large volume reduction factors, about 100 to 1. For wet solids, technologies include sedimentation, drying, dewatering, dehydration, and incineration. For liquid wastes, the technologies include evaporation, distillation, crystallization, precipitation, centrifugation, filteration/ultrafiltration, sedimentation, ion exchange, and reverse osmosis. In addition, the higher activity waste can be stabilized through bituminization, cementation, or vitrification. Many of the utilities now employ the services of Scientific Ecology Group's (SEG) centralized waste volume reduction facilities located in Oak Ridge, Tennessee.
QUALITATIVE ANALYSIS
Definitive information on design of the planned facilities for capacity design basis or on the basis of per year planned waste acceptance and the life cycle of the facility are not available for many of the compacts and states. Because of the lack of such information, it is not possible to do a quantitative analysis of generation vs. disposal capacity. In addition, the past experience at the compacts suggests that it is a dynamic process with a number of very significant albeit nontechnical factors. Thus, only a qualitative assessment is feasible.
We can look at some specific examples. In the case of Texas, the design basis for the Texas facilities is 3 million ft3 with a facility life cycle of 30 years. This essentially means a design basis of 100,000 ft3 per year. However, the state authority recognizes the declining volumes and the planning volumes are currently in the 40,000 to 50,000 ft3 per year range. The data over the past 11 years from 1985 to 1995, show an average wast volume generation of about 33,000 ft3 per year, even though wide fluctuations have occurred from year to year, from a low of 2935 ft3 in 1995 to a high of 162,844 ft3 in 1992. Even though Texas is now aligned with Vermont and Maine as a compact, both states are not major generators of LLW. Based on the five year data from 1991 to 1995, the average annual volumes were about 6,200 ft3 for Vermont and 4,800 ft3 for Maine. It clearly fits in with the Texas facility rationale of a planned volume in the 40 to 50 thousand per cubic feet per year range. It is also clear that the design capacities planned early in the compacts history may no longer be valid or needed.
In Massachusetts, for a hypothetical above ground vault facility, the state has estimated development costs based on four potential capacity figures. These figures are 35,000 ft3 per year, 50,000 ft3 per year, 80,000 ft3 per year, and 467,000 ft3 per year. For comparison, the data over the past 11 years , from 1985 to 1995 show that the waste shipped for disposal was on the average of about 39,000 ft3 per year. Again, for Massachusetts, an unaffiliated state, this wide variation shows the difficulty of assessing the true disposal capacity need with any degree of certainty. With the reopening of Barnwell facility to the outside waste again on July 1, 1995, Massachusetts generators can avail of the disposal facility there in the near-term. In addition, some waste meeting the Envirocare of Utah's license conditions can be shipped to its facility in Clive, Utah.
In the Southeast compact, the situation remains in a flux. South Carolina pulled out of the Southeast compact about a year ago and is now an unaffiliated state. Current estimates for the remaining disposal capacity at Barnwell facility in South Carolina, based on the current volumes, are 18 to 20 years. Chem Nuclear, the operator of the site has estimated a remaining capacity of about 8.5 million cubic feet. The volume of waste received can fluctuate significantly from year to year. Barnwell received 485,000 ft3 of waste in 1995; in 1996 this volume was down to 326,000 ft3 including the decommissioning waste from Yankee Roe in Massachusetts. Nevertheless, nationally, Barnwell still receives about 70 % of the total waste shipped for disposal. Even though the decommissioning waste may be factored into the remaining capacity estimates for Barnwell, there is no accurate way to predict the waste volumes arising due to decommissioning activities in future. Decommissioning waste is really the "wild card" in the capacity game. Smaller volumes may not put any significant demands on the existing capacity availability in future; larger volumes, however, could strain the availibilty and necessitate development of further disposal capacity.
In North Carolina, the host state for the Southeast compact, it is not the question of the capacity per se but that the state law will put a limitation on the total waste by volume in the facility or the 20 year operational life cycle, whichever comes first, and the state will have the right to refuse waste after such a condition is met.
The Northeast compact has an estimated 50 year or more capacity available at Richland, Washington, considering a waste volume of less than 100,000 ft3 per year. Data from 1985 to 1995 have averaged to about 69,000 ft3 per year, even though it has ranged from a low of 12,160 ft3 in 1995 to a high of 152,224 ft3 in 1987. The facility is currently operated by U.S. Ecology on DOE-owned land, leased to the state of Washington. During 1996, the facility also received waste from Fort St. Vrain decommissioning project in Colorado.
In the Central compact where Nebraska is the host state, controversial question remains whether there is enough waste volume to make a viable facility. Generally speaking similar questions are valid for many other states and compacts.
Given the declining volumes as shown in Fig. 1, and given the future capacity projections at Barnwell and Richland, it can be concluded that development capacities as originally planned by the compacts and unaffiliated states may not be necessary. The key question may not be the existing disposal capacity but whether it is accessible. As the experience with the closing of Barnwell site to outside waste, albeit for only one year, has shown, uncertainty in access to disposal can be the key factor in compacts developing their own disposal facilities. Current exclusion of North Carolina from access to Barnwell also shows the essential dependency of the access to disposal on political considerations. On the other hand as Texas example shows, originally planned disposal capacities may not be matched to the current or future waste generation volumes. As the volumes decline, questions arise whether it is necessary to spend large amounts of money on developing large facilities, or facility capacities should be inherently tied to the projected needs, in some modular design fashion.
Given the overall situation at the present the question must be asked - Are too many sites being developed? There is no technical obstacle to disposing of all LLW in the United States at one location. However, there appears to be no political will or way to build one site to serve all of the states because of equity arguments. Internal political opposition in the states with disposal facilities could lead to a determination that a greater distribution of the burden is necessary. The local community sentiment, often described as "not in my backyard" opposition, will continue to be a significant impediment and will not disappear.
The real "wild card" is the decommissioning waste. As several of the nuclear power reactors approach the end of their design life or are decommissioned for other reasons, the quantity of waste generated could increase significantly which in turn could put disproportionate demand on the existing waste disposal capacity.
Another important factor that will change the whole equation of future capacity needs is the concept of Below Regulatory Concern (BRC) or de minimis. The concept of an established lower boundary, the radiometric value below which the waste is no longer considered to be hazardous in a regulatory sense has been discussed in detail by the International Atomic Energy agency (IAEA). The IAEA recommended value for exemptible waste is 1mrem/yr. In the United States, the BRC was mandated, established, reviewed, and revoked by Congress through the Nuclear Regulatory Commission in a series of actions during the period of 1985 to 1993. This withdrawal of the BRC rule has opened up the possibility of major problems in nuclear waste in the areas of economic evaluation, engineering design, and remediation. It has also left major waste classifications such as Naturally Occurring Radioactive Material (NORM), Accelerator Produced Radioactive Material (NARM), and Class A low level waste with a needed definition of a lower limit. Such a lower limit is necessary for future applications to be developed in the areas of reuse and recycling of materials. Additionally, without a regulated lower limit, it is impossible to decontaminate, decommission, or remediate any licensed nuclear facility on a consistent national basis. Such a limit will also impact the capacity projections of future waste disposal facilities.
CONCLUSION
For all the good intentions of Congress, the time frames established in the LLRWPA and LLRWPAA were not sufficient. While the formation of regional compacts represents a significant step, not enough progress has been made in developing new disposal capacity during the past sixteen years. The siting process has proven to be very complex, time-consuming, and contentious.
While the development of new disposal sites by the compacts has continued to be stalled or delayed, the nuclear power industry has undergone dramatic changes as far as the generation and processing of LLW are concerned. There have been significant reductions in other generation sources of LLW also. The waste volumes for disposal have decreased dramatically during the past ten years, mostly driven by the escalating disposal cost. As waste volumes decline, questions are being raised whether it is necessary to continue with developing additional disposal facilities. As a number of the compacts have found in their continued planning process, the issue of disposal capacity matched to the anticipated need is a dynamic one.
A number of factors, both technical as well as nontechnical, affect the issue of disposal capacity development versus waste volume generation. Based on the current waste volumes, the capacities at Barnwell and Richland could be sufficient for the waste generated during the next two to three decades. However, political considerations, and equity considerations may force the sharing of the burden may be necessary through regional facilities. On the other hand, economics may become the driving force for the continued use of the existing facilities as the first choice. For example, South Carolina is using the state tax of $235 per ft3 on the waste disposed at Barnwell to fund the state education programs. So long as the generators have assured access at affordable cost, they will continue to use Barnwell and Richland facilities. Use of centralized waste volume reduction facilities, such as, the SEG facilities at Oak Ridge, can provide generators the ability to reduce volumes and hence save on disposal cost.
The real "wild card" is the decommissioning waste. As several of the nuclear power reactors approach the end of their design life or are decommissioned for other reasons, the quantity of waste generated could increase significantly which in turn could put disproportionate demand on the existing waste disposal capacity. Any further action by the Nuclear regulatory Commission on the definition and acceptance of an exemptible waste will also affect the need for future disposal capacity.
BIBLIOGRAPHY