The Environmental Protection Agency expects to issue its Record of Decision for cleanup of the radioactively contaminated West Lake Landfill in Missouri by Sept. 30.
The agency’s preferred option for cleanup is called partial excavation: removing soil contaminated at 52.9 picocuries per gram or more to 16 feet below ground, then covering the area.
Some residents near the Environmental Protection Agency (EPA) Superfund site in the St. Louis area expressed concern that the July 5 resignation of EPA Administrator Scott Pruitt might delay progress in the cleanup plan.
“Acting EPA Administrator Andrew Wheeler has been briefed multiple times on the West Lake Superfund site beginning when he was Deputy Administrator and continues to be actively engaged,” an agency spokesperson said by email on July 13. “He is committed to making a sound decision and moving this site forward as it has been listed on the National Priorities List for decades.”
The EPA administrator must sign off on any Superfund project that costs more than $50 million.
In February, the EPA said the preferred alternative would likely be a five-year project that would cost $236 million; a 2017 EPA draft feasibility study said partial excavation would cost $276 million.
The 2017 feasibility study cited seven potential options for the two West Lake sites, mostly some form of partial or full excavation. Costs range from $75 million for merely covering the contaminated sites to $695 million for excavating and removing all “radiologically impacted materials,” EPA has said. Total excavation would take almost 15 years, the agency estimates.
Partial excavation would remove 70 percent of the radioactivity from the two contaminated West Lake sites, EPA has said.
Together, the sites hold 8,700 tons of low-level radioactive wastes, which in 1973 were mixed with l38,000 tons of soil. EPA has not decided if the removed waste will be buried in a specially lined site at the landfill, or at another location. The two West Lake locations were filled prior to passage of laws requiring lining for landfills.
The 200-acre West Lake Superfund complex encompasses both the Bridgeton and West Lake landfills, which include several burial sites. A smoldering underground fire at the Bridgeton section is threatening the buried radioactive materials at the West Lake section, which is about 1.5 miles from the Missouri River.
West Lake’s groundwater was found to have unsafe levels of radioactive uranium, radium, and thorium-230 during tests from 2012 to 2014. Most of that is Thorium-230: a decay product of uranium processed at St. Louis’ Mallinckrodt Chemical Works facility during World War II for the Manhattan Project.
Once the West Lake plan is finalized, the EPA will begin working with the potentially responsible parties for West Lake, who will be on the hook for remedial design and action, and the cleanup bill. Potentially responsible parties are the Department of Energy, power company Exelon, and site owner Republic Services.
