Until 1970, radioactive wastes heavily contaminated with plutonium and other transuranic radionuclides (elements with atomic numbers greater than that of uranium) were, for the most part, managed in the same way as "low-level" radioactive wastes and dumped into shallow land burial sites. Beginning in 1970, a new waste classification, transuranic (TRU) waste, was created. It was defined as waste containing greater than 10 nanocuries per gram of transuranic elements with half-lives greater than 20 years (relaxed in 1984, to 100 nanocuries per gram ).¹ TRU wastes are a concern because of the long half-lives and health dangers of transuranic elements, such as plutonium-239, and have been deemed dangerous enough to be disposed of in a deep geologic repository.

To further complicate the picture, some sites in the DOE weapons complex had their own definitions of TRU waste prior to 1970 that did not match subsequent Atomic Energy Commission (AEC) or DOE definitions. Some other sites ignored the 1970 AEC rule and continued to bury or otherwise dispose of TRU wastes. For example, between 1966 and 1984, Oak Ridge TRU wastes were mixed with cement and pumped into deep rock formations (a practice called "hydrofracture"), which resulted in contamination of the groundwater. Some of the TRU wastes that were classified as "retrievably stored" were, in fact, improperly managed and have now been designated as "buried waste," as for instance at Oak Ridge and Savannah River. The confusion in regulations and practice and lack of enforcement has complicated clean-up because the various TRU waste categories are now mixed up in burial areas.

In addition, data on the volume, mass, and radioactivity of buried transuranic waste and transuranic soil are inconsistent among DOE sites and poor overall. DOE's data on radioactive waste were, until recently, compiled annually in its Integrated Data Base Reports.² However, the data on TRU waste vary inexplicably from year to year and are inconsistent with those reported in other documents (see tables on buried TRU waste for details). For instance at Los Alamos, there are two quite different estimates of the amount of plutonium in the waste - one of 610 kilograms published by DOE headquarters in its report, "Plutonium: The First 50 Years"³ and the other of 1,375 kilograms published in various other sources.⁴ The enormous difference of 765 kilograms - enough to make more than 150 nuclear weapons - has not been explained so far as we are aware.

The DOE has no standard method for collecting and recording TRU waste data, nor has it been able to provide any rationale for the discrepancies. IEER's report demonstrated that DOE TRU waste data were hopelessly flawed and inconsistent for all sites except the Idaho National Engineering and Environmental Laboratory where some effort had been made to develop fact-based data. In five months of effort, the DOE could not provide IEER with evidence of any technical guidance or quality assurance methods used by it or its contractors to ensure the integrity of the data.

The only study of actual records that has been done (conducted for buried TRU waste at the Idaho Lab) estimated that the transuranic radioactivity was nine to twelve times higher than previously estimated and contained three times as much mass of transuranic radionuclides⁵. Despite this startling finding, DOE did little or nothing to try to arrive at better estimates of buried TRU waste quantities at other sites, or to reassess its strategy for managing these wastes. It took the publication of the IEER report for the DOE even to acknowledge that there may be a problem worth examining.

Based on the data available, it seems that roughly two-thirds of the waste is buried in shallow pits and trenches (generally before the 1970 directive ended this practice). The other one-third is kept in "retrievable storage," mostly in covered, above-ground facilities.

DOE is putting most of its TRU waste management money into the area that is least urgent - sending retrievably stored waste to the Waste Isolation Pilot Plant (WIPP) in New Mexico (see box). Of all TRU waste, the retrievably stored wastes pose the least short- and medium-term risks, since they are generally monitored and stored in covered facilities, or are in the process of being moved to such facilities. Newly-generated TRU wastes are also being monitored and retrievably stored. WIPP cannot accommodate the wastes that make up far more of the problem: buried TRU waste and associated highly contaminated soil. This waste threatens many vital water resources, including the Snake River Plain Aquifer, the Columbia River, and the Tuscaloosa Aquifer (located beneath the Savannah River Site). Despite these risks, DOE has put a low priority on buried TRU waste, TRU contaminated soil, and the aquifers they are threatening.

The high priority given to the WIPP repository does not arise out of environmental considerations. Rather it is driven by political and associated legal commitments made during the Cold War, notably to the state of Idaho, that stored TRU waste would be moved to a repository. DOE's commitment to WIPP is in direct contradiction to its stated policy of giving high priority to projects for managing and eliminating "urgent risks."⁶ At this stage the most important task, from the standpoint of safeguarding the environment and human health, is the protection of water resources from further contamination and the removal and stabilization of buried TRU waste and TRU soil.

DOE's few attempts to deal with buried TRU waste have been inadequate and misguided. Rather than develop a comprehensive plan that would begin with careful characterization of the problem and thorough technology development, DOE has wasted most of the relatively small resources devoted to the buried TRU waste problem. It has been pursuing in-situ vitrification, an inappropriate and inadequate technology.⁷ Its Pit 9 project at the Idaho National Environmental and Engineering Laboratory was an ill-advised experiment in "privatization" that led to huge cost increases, technical failure, disputes, and delays instead of actual progress on reducing the risks posed by buried waste.

Justification for leaving TRU waste in shallow land burial rests on an assumption that transuranic elements are relatively immobile in the environment. Based on some laboratory data and computer models that did not reflect field data, DOE predicted that it would take hundreds of thousands of years for the plutonium to travel distances of a few tens of meters. However, rapid migration of transuranic elements has been documented at several sites. A 1995 study at Oak Ridge found "significant and rapid"⁸ transport of curium-244, a transuranic element. A 1998 study at Oak Ridge indicates that contaminants show signs of rapid transportation "with little retardation."⁹ At the Idaho Lab, americium-241, another transuranic element, has been detected in the Snake River Plain Aquifer 580 feet below the burial areas. Measurements in wells at the Nevada Test Site have provided evidence that plutonium can and does bind to small ("colloidal") particles that may then travel "a significant distance through fractured volcanic rock."¹⁰ Measurements of the soil beneath the high-level waste tanks at the Hanford site show that plutonium has migrated a "surprisingly far distance" and has been measured as deep as 100 feet at elevated concentrations.

In light of our findings on DOE's management of TRU waste, IEER makes the following recommendations:

1. DOE should work with Congress and the affected states to stop the WIPP program and reorient the TRU waste management program to address buried waste and TRU-contaminated soil. Monitoring of retrievably-stored waste should be continued. TRU waste and high-level waste management should be merged into a single program for wastes designated for repository disposal. The Yucca Mountain repository program for high-level wastes should also be cancelled, so that the scientific work on how to isolate both transuranic and high-level wastes from the human environment can be put on a sound scientific footing.

2. DOE should immediately create a program of estimating the volume and activity of buried TRU waste along the lines of the Idaho Lab's effort. The overall effort could perhaps be modeled on the plutonium and uranium vulnerability studies.

3. DOE should abandon the strict distinction between the current TRU waste classification (100 nanocuries per gram) and waste with somewhat lower TRU concentrations (10 to 100 nanocuries per gram) and proceed to treat all waste associated with TRU burial areas as TRU waste, unless there is a technically and economically defensible rationale to do otherwise.

4. DOE should examine the feasibility of excavating all buried TRU waste and associated soil and storing it retrievably along with TRU waste that is already classified as retrievably stored. Due to the existing soil and groundwater contamination caused by buried TRU waste, as well as the long half-lives of transuranic radionuclides, institutional controls and caps are especially inappropriate solutions. It is impossible to maintain institutional controls for periods that might approach even a single half-life of plutonium-239 (over 24,000 years) and caps merely cover up the contamination without ensuring its isolation from the groundwater.

5. DOE should pursue a more technically-sound effort to develop safe retrieval technologies for TRU waste. Particular attention should be given to serious hazards that could affect worker safety and health, including explosives and highly toxic materials that may be buried at some sites.

1. The Nuclear Regulatory Commission definition puts the half-life minimum at five years. For anomalies in official definitions, see "The Curious Case of Curium" in Science for Democratic Action Vol. 6 No. 1, p. 12.

2. In December 1998, the DOE settled a 10-year lawsuit with 39 public interest groups over DOE's failure to conduct a PEIS for environmental remediation. Among other outcomes, the agreement requires DOE to create a regularly-updated public database on nuclear wastes stored and generated at DOE sites from all department activities. The data is to include waste types, volume, radioactivity, and transportation plans. Also as part of the settlement, plaintiff groups agreed not to bring legal action against DOE based on its failure to conduct a PEIS for environmental restoration and waste management.

3. US DOE, Plutonium: The First 50 Years: United States Plutonium Production, Acquisition, and Utilization from 1944 to 1994, (Washington: US DOE, February, 1996), p. 82.

4. DOE Memorandum to Jenny Craig, EM-24, Office of Environmental Management, from Richard J. Guimond, Admiral, Assistant Surgeon General, USPHS, Principal Deputy Assistant Secretary for Environmental Management, and Everet H. Beckner, Principal Deputy Assistant Secretary for Defense Programs, January 30, 1996, Attachment B.

5. Lockheed Martin Idaho Technologies Company, A Comprehensive Inventory of Radiological and Nonradiological Contaminants in Waste Buried in the Subsurface Disposal Area of the INEL RWMC During the Years 1952-1983, INEL-95/0310, Rev. 1, (Idaho Falls, ID: Idaho National Engineering Laboratory, August 1995).

6. The Environmental Management program states it as follows "Goal 1: Eliminate and manage urgent risks." US DOE, Environmental Management 1996: Progress and Plans of the Environmental Management Program, DOE/EM-0317, (Washington: DOE Office of Environmental Management, November, 1996). See also US DOE, Accelerating Cleanup: Focus on 2006, Discussion Draft, DOE/EM-0327, (DOE Office of Environmental Management, June, 1997), p. 2-2.

7. In-situ vitrification involves placing electrodes into the ground in a waste pit surrounded by materials (graphite and glass frit) that act as a "starter path" for an electrical current. The current travels along the starter path material to the adjacent contaminated soil in the pit, causing it to melt. Radionuclides in the soil are either incorporated into the molten soil or are burned off - gases are collected with a hood placed over the area. It can destroy organic toxic material in the soil and immobilize radionuclides. But the glass is frequently of poor quality, and cracks in the matrix could cause rapid leaching of contaminants.

8. R.B. Clapp and J. A. Watts, eds., Fourth Annual Environmental Restoration Monitoring and Assessment Report (FY 1995), DOE/OR/01-1413&D1, (Oak Ridge, TN: Environmental Sciences Division, Oak Ridge National Laboratory, ESD Publication 4463, issued September, 1995), p. 4-20.

9. John F. McCarthy, William E. Sanford, and Paige L. Stafford, "Lanthanide Field Tracers Demonstrate Enhanced Transport of Transuranic Radionuclides by Natural Organic Matter," Environmental Science and Technology, web edition (http://acsinfo.acs.org), ASAP article, Nov. 11 1998.

10. A.B. Kersting, et al, "Migration of Plutonium in Groundwater at the Nevada Test Site," in David K. Smith et al, Hydrologic Resources Management Program and Underground Test Area Operable Unit: FY1997 Progress Report, UCRL-ID-130792, (Livermore, CA: Technical Information Department, Lawrence Livermore National Laboratory, May, 1998), pp. 76-92.