After two years of delay, the U.S. Environmental Protection Agency announced on Thursday that it will move ahead with plans to build a firebreak at a landfill complex in north St. Louis County.
A fire has been smoldering underground at the Bridgeton Landfill since late 2010, about 1,000 feet away from tons of radioactive waste buried in the adjacent West Lake Landfill.
The landfills' owner, Republic Services, first agreed to build a firebreak in late 2013, but the EPA delayed its construction, saying more tests were needed to determine the extent of radioactive contamination. The EPA has not yet released the results of those tests or a map showing the boundaries of the radioactive waste at the landfills, but an agency spokesperson said it would do so early in 2016.
In a written statement, EPA Acting Regional Administrator Mark Hague called mitigating the potential impacts of a "subsurface smoldering event" at the landfills a "top priority" for the agency.
“We are now working through the highly complex details of implementing our decision and the associated legal steps," Hague said. "Once the plan is finalized, we are committed to providing this information to the public,” Hague said. “EPA will use all available enforcement authorities to ensure implementation of this work.”
As announced last year, the EPA will oversee the construction of the firebreak with input from the U.S. Army Corps of Engineers. Under the EPA's Superfund program, the costs of building the underground fireproof wall would be borne by Republic Services, along with the Chicago-based power company Exelon and the U.S. Department of Energy.
The EPA said it would release more information about the firebreak, including its location within the landfill complex and a timeline for its construction, "once plans are finalized."
In addition to a "physical isolation barrier," the EPA is calling for other engineering controls at the landfills such as subsurface "cooling loops."
Earlier this month, the EPA ordered measures to be taken to prevent surface fires at the landfills, including removing vegetation from areas known to contain radioactive waste and covering them with fireproof materials like dirt or gravel.
The EPA has committed to issue a proposed decision for what to do with the radioactive waste at the West Lake Landfill by December 2016. After giving the public the opportunity to comment on the plan, the agency will issue its final decision sometime in 2017.
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