United States Office of Solid Waste Environmental Protection and Emergency Response EPA/530-SW-9t-026 Agency Washington DC 20460 October 1990 Office of Solid Waste vvEPA Environmental Fact Sheet ERA'S FINAL CONDITIONAL NO-MIGRATION DETERMINATION FOR DOE'S WASTE ISOLATION PILOT PLANT BACKGROUND The 1984 Amendment to the Resource Conservation and Recovery Act (RCRA) imposed substantial new requirements on the land disposal of hazardous waste. Land disposal of waste is prohibited unless the waste is treated to meet best demonstrated available technology (BOAT) standards specified by EPA. As of May 1990 all wastes that were listed or identified as hazardous before November 8, 1984 cannot be land disposed unless they have been treated to BOAT standards, or unless the EPA Adminstrator determines that the prohibition is not required in order to protect human health and the environment for as long as the waste remains hazardous. This determination must be based on a demonstration through a "no migration petition" by the facility owner or operator that the waste will not migrate from the disposal unit or injection zone for as long as the wastes remain hazardous. In March 1989, the Department of Energy (DOE) submitted a no- migration petition to EPA for its Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico. DOE has designed the WIPP as a permanent repository for mixed hazardous and radioactive wastes that are generated and stored at ten DOE sites around the country. These wastes, which result from the decommissioning and production of nuclear weapons, consists of a variety of materials, some contaminated with hazardous wastes such as solvents and metals. Specifically, these materials include tools, equipment, protective clothing, rags, contaminated organic and inorganic sludge from wastsewater treatment operations; cemented process and laboratory wastes; and other material contaminated during the production and reprocessing of plutonium. ------- -2- Because of uncertainties related to the long-term performance of the repository, DOE has proposed to place a limited amount of waste underground for testing during the duration of the experimental program. Based on the results of the experimental program, a decision would be made as to whether the repository is appropriate for permanent disposal of mixed wastes. If the WIPP proves acceptable as a permanent repository other DOE facilities will ship drums, metal boxes and canisters of waste to the WIPP and they will be placed in underground rooms. The wastes must be backfilled with crushed salt and a clay mixture and then the rooms will be sealed. After an operating period of approximately 25-years, DOE would seal the shafts of the mine with cement plugs and compacted salt, and decommission the facility. ACTION EPA's decision today will allow DOE to place limited amounts of waste in the WIPP repository for the sole purpose of testing and experimenta- tion. If the tests fail to show that the site is acceptable for permanent storage. DOE must remove the waste from the repository. EPA has concluded that DOE has demonstrated to a reasonable degree of certainty that hazardous constituents will not migrate from the WIPP disposal unit under the conditions imposed in today's decision. EPA has thoroughly reviewed available information on the expected long- term performance of the WIPP repository. EPA believes that the WIPP is a promising site based on the geological stability of the area, the depth, thickness and the extremely low permeability of the salt formation in which the repository has been mined, and the properties of the rock salt as an encapsulating medium. This final determination establishes several conditions (appended) on DOE activities at the WIPP. Activities are limited to the testing and experimentation which is necessary to demonstrate long-term acceptance. Wastes must be retrieved from the depository if DOE, as a result of the testing, cannot demonstrate the long-term applicability of the site. The quantity of waste that DOE can place in the WIPP is limited to 8,500 drums, or one percent of the facility's final capacity. This determination also requires that DOE place the wastes in the repository in a readily retrievable form. DOE must monitor air emissions from the repository at the site. DOE must also test for flammable gases and. if found, wastes cannot be shipped to the WIPP. Finally, waste destined for the WIPP must undergo certain waste characterization analysis. ------- -3- EPA emphasizes that this final determination addresses only the specific question of whether hazardous constituents will or will not migrate from the WIPP. EPA's authority under RCRA over waste destined for the WIPP extends only to mixed waste, and it is further limited to the hazardous components of the mixed waste. The potential release of radioactive material from the WIPP is addressed under the Atomic Energy Act. Issues raised by the handling and possible treatment of waste before it reaches the WIPP. are beyond the scope of this final determination. CONTACT For further information, or to order a copy of the Federal Register notice, please call the RCRA Hotline Monday through Friday. 8:30 a.m. to 7:30 p.m. EST. The national toll-free number is (800) 424-9346; for the heaing impaired, it is fTDD) (800) 553-7672. In Washington. D.C.. the number is (202) 382-3000 or TDD (202) 475-9652. ------- CONDITIONS OF NO-MIGRATION DETERMINATION In granting the no-migration determination to DOE during the test phase for the WIPP. EPA requires that DOE meet the following conditions: o Wastes must be used for purposes of testing and experimentation to determine the long-term acceptability of the WIPP. (Placement of waste for purposes of conducting an operations demonstration is specifically prohibited.) o No more that 8500 drums (one percent of the repository) may be placed in the WIPP. o All mixed wastes must be removed if DOE cannot demonstrate no-migration for the permanent disposal of mixed wastes before the expiration of this determination. o Wastes must be placed in a readily retrievable manner. o DOE must install and operate a carbon adsorption device in the discharge system of the bin experiment rooms; they must also monitor the outlet airstream and keep appropriate records. o DOE must implement an air monitoring plan. o DOE must conduct waste testing and keep appropriate records for the following: -Test the headspace gases of each drum or individual container to be placed in the WIPP to ensure that they are not flammable or do not contain mixtures of gases that could become flammable when mixed with air. -Test the headspace gases of containers to be used in the bin-scale tests to ensure that they are compositionally similar to the data provided in the no-migration petition. o DOE must demonstrate the comparability of the headspace gases from the bin-scale wastes to the headspace gases from wastes described in the no-migration petition before placing wastes in the WIPP for the alcove tests. o DOE must provide annual reports to EPA on the status of the performance assessment during the test phase. ------- |