This story was updated Oct. 20 with a response from Republic Services — The Missouri Department of Natural Resources has ordered Bridgeton Landfill LLC owner Republic Services to study the increased groundwater contamination detected at the site.
In a letter addressed to Republic Services engineer Erin Fanning last Friday, MDNR engineer Charlene Fitch provided a detailed review of groundwater sampling reports that span from October 2014 to April 2016. The sampling was conducted by a contractor hired by Republic Services. It noted increasing levels of hazardous substances that exceed federal levels, particularly benzene, which can increase the risk of cancer to those exposed to it.
The Bridgeton Landfill contains an underground smoldering fire, which sits approximately 600 feet from World War II-era nuclear waste under the West Lake Landfill Superfund site.
The state has required Republic Services to take a number of actions, which include a study of the direction in which the groundwater contamination is flowing and installing additional wells at the site.
Area resident Dawn Chapman, who runs the Just Moms STL activist group, is worried the contamination could mix with radioactive waste.
"Depending on the direction the groundwater moves, even if it moves only one direction for a week or so in a year, if it's moving towards and interacting with the radiological material in the ground, then we have a big problem," Chapman said.
The company must also notify nearby property owners about the contamination. Chapman said that would likely include business owners in Earth City.
"After years of intensive groundwater monitoring, there has been no evidence of off-site downstream impacts attributable to the landfill," said Russ Knocke, Republic Services' vice president of communications and public affairs. "Federal regulators have been clear that no one will ever drink or use the groundwater at the site. It will never be a public water source. These test results are unlikely to affect any regulators' plans. In addition, MDNR's letter will not change the ongoing, comprehensive groundwater monitoring regime and liquids management processes at the site."
Republic Services has spent more than $200 million in treatment and monitoring infrastructure at the Bridgeton and West Lake landfills. Recently, a cooling barrier was installed in the neck, the area between the landfills.
However, activists and residents demand that state and federal regulators conduct more thorough testing for contaminants, especially off-site.
"They [need] to put forth a meaningful sampling plan that involves digging wells beginning at the landfill, which they have, and moving outward to determine the extent of the contamination," said Ed Smith, policy director for the Missouri Coalition for the Environment.
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