Updated at 1:25 p.m. to add statement from Republic Services, and at 6:00 p.m. to add comments from EPA.
More radioactive material has been found at the West Lake Landfill in Bridgeton.
The material was detected during radioactivity testing in preparation for the construction of a trench. That trench will separate radioactive waste at the West Lake Landfill from an underground fire smoldering at the adjacent Bridgeton Landfill.
The U.S. Environmental Protection Agency is overseeing the construction of the firebreak trench.
According to a briefing paper the EPA provided to elected officials on Monday, contractors working under EPA oversight detected some "radiologically-impacted material" at "a handful of locations generally situated along one edge of the area being surveyed" for the construction of the trench.
The "Gamma Cone Penetration Testing" involves pushing a probe into the ground to look for radioactivity readings above normal background levels. The EPA says that testing, which began on Oct. 28 and ended on Nov. 26, found radioactive material 24-34 feet below the surface of the landfill. This is the first time radioactive material has been detected in these areas.
In a letter to EPA Regional Administrator Karl Brooks dated Nov. 27, Missouri Attorney General Chris Koster said the following about those preliminary test results:
"After reviewing the report, the State is concerned about some of the raw data summaries, which suggest the presence of higher-than-background-level radioactivity at depth outside the are where previous maps represented the radioactive material was located."
Koster goes on to ask the EPA to complete a comprehensive survey of the landfill to determine "with certainty" the boundaries of the radioactive material "without delay."
"In addition, due to the importance of this data and the high level of public interest in the site, the State strongly encourages EPA to make the information publicly available as soon as EPA validates the data for accuracy."
You can read all of the Koster's letter to EPA here.
EPA Regional Administrator Karl Brooks responded in letter dated Nov. 29, 2013. He says his agency has ordered a more comprehensive engineering survey of radioactivity in the area between West Lake Landfill and Bridgeton Sanitary Landfill, "to more precisely determine the extent and location of radiologically-impacted material."
Here is an excerpt of that response letter:
You can read all of the EPA's response letter here.
In an interview on Tuesday with St. Louis Public Radio and the Beacon, Brooks said the expanded radioactivity survey would start in one or two weeks, with new equipment.
“The equipment will be able to reach further down under the ground, it’ll be able to go through some of the construction debris that was encountered there, and provide additional information,” Brooks said.
And he reiterated that the latest findings do not change EPA's assessment of the risks.
“People who live and work in that neighborhood are not at risk from this buried material under the ground, or from the work that’s being done there during the survey,” Brooks said.
The fire smoldering below the surface of the Bridgeton Landfill was discovered by the landfill's owner, Republic Services, in 2010. Area residents found out about the fire when foul smells emanating from the landfill increased and began causing health problems.
In response to our request for comment about the new radioactivity findings, Republic Services provided the following statement:
"Together with the EPA, the West Lake Landfill continues to evaluate preliminary, uncorroborated data from a low-level gamma detection outside of the area where radiological contaminants are known to be buried within West Lake Landfill.
This material is estimated to be roughly 30 feet below ground, and is within a secured portion of the site that is closed to public access.
This recent detection is precisely why we are conducting thorough gamma detection tests before making any final barrier construction plans.
The EPA has reiterated that the recent detection does not change the Agency’s assessment that the buried radiological contaminants at West Lake Landfill do not pose a current risk to public health or safety."
Although the EPA is responsible for the oversight of the West Lake Landfill -- the federal Superfund site where the radioactive material is located -- the Missouri Department of Natural Resources is responsible for overseeing the Bridgeton Landfill and its underground fire.
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