EPA contractor removing the contaminated pond liner above
The Emergency Response and Removal Branch (ERRB) initiated an emergency removal action at Starmet (“Site”) on June 24, 2002, to prevent the release of depleted uranium from the wastewater retention ponds behind the facility and to mitigate other risks posed by hazardous materials on site. U238 is listed in the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) as a hazardous substance. The pond liners were in poor condition and there were indications that the liner system was failing. At the time of the initial response, the ponds were in danger of overflowing due to heavy rains. EPA treated the wastewater with by heat induced evaporation followed by solidification of the wastewater brine. The solids were disposed of in the Envirocare Landfill in Clive, Utah.
Extensive work is required to remove the large quantities of radioactive materials remaining from Starmet operations. At the commencement of the removal, EPA assessed over 12,000 drums of improperly stored UF4 as well approximately 3,700 drums of calcium fluoride on site from Starmet operations. Other low-level radioactive wastes left on site include magnesium fluoride and dry activated waste (i.e., HEPA filters contaminated with trace levels of uranium). Addutinally, there were hundreds of tons of radioactive debris on site.
Effective February 13, 2004, EPA entered into a multiparty Administrative Order on Consent (AOC) with the United States Enrichment Corporation (USEC), the Department of Energy (DOE), and the Department of the Army to complete the time critical removal at the Starmet site. Under the terms of the AOC, USEC is conducting a PRP-lead removal (“USEC-lead work”) for all waste materials associated with the conversion of USEC uranium hexafluoride to uranium tetrafluoride (UF4) after July 28, 1998 (the date USEC became a private entity). USEC-lead work includes the removal of approximately 5,700 drums of UF4, 3,600 drums of calcium fluoride (with radioactive residual), hydrogen fluoride, and associated dry active waste. The USEC portion of the removal accounts for approximately 38% of the total removal action.
Concurrently, EPA has commenced a fund-lead removal (“EPA-lead work”), financed by a special account established by DOE/the Army through the United States Judgement Fund. EPA is removing 6,200 drums of UF4 and hundreds of tons of radioactive waste metals, and other radioactive waste materials associated with production of uranium metal under DOE and Army contracts.
EPA accomplishments on site to date include:
1. Treatment of 530,000 gallons of uranium contaminated wastewater. The water was treated with heat-induced evaporation. The brine was solidified with polyacrylate to form a green gel suitable for transportation and disposal off site to an approved landfill in Utah. (in progress);
2. Closure of the ponds. The liners and contaminated soil were removed, and the ponds were backfilled with clean fill.
3. Treated and stabilized 1651 lbs of pyrophoric shavings that are the byproduct of the manufacture of uranium derbies. The uranium shavings are dissolved and oxidized to form a stable solid. (completed)
4. Neutralized 480 gallons of plating vat acids and consolidated neutralization sludges. Acid liquids were removed from vats in the cadmium counter-weight plating line. Acid liquids were neutralized by adding a lime slurry consisting of hydrated lime and water to a mixing tank, containing the acids in small quantities, while the pH was monitored. The neutralized liquids were dried and then consolidated. (completed)
5. Upgrade of the facility fire suppression and alarms.
6. Packaging, transport, and disposal of over 5,500 drums of UF4.
7. Characterization and disposal of 78 B-25 boxes filled with radioactive debris.
8. Removal, transport, and disposal of hundreds of tons of low-level radioactive debris.
Site Background
The Starmet CMI, Inc., facility, located in Barnwell, South Carolina, converted uranium hexafluoride (UF6) to the more stable uranium tetrafluoride (UF4) and re-plated uranium counterweights for the airline industry. A portion of the UF4 was converted to uranium metal and used in manufacturing. The South Carolina Department of Health and Environmental Control (DHEC) issued an Emergency and Administrative Order to Starmet CMI, Inc. on June 24, 2002, based on numerous violations of the facility's Atomic Energy and Radiation Control Act license (issued by DHEC) and DHEC regulations. This order required the facility to cease operations.
