Ameren has begun addressing this contamination and submitted workplans to EPA to conduct additional cleanup actions

LENEXA, KAN. (FEB. 9, 2023) – Laboratory results from field work conducted by EPA in St. Charles, Missouri, in January have identified the Ameren Huster Road Substation as a source of vinyl chloride and cis-1,2-dichloroethene contamination in the city of St. Charles’ Elm Point Wellfield. With the new sampling results, EPA will now require Ameren to address the contamination originating from the substation.

“The Superfund program operates under the ‘polluter pays’ principle,” said EPA Region 7 Superfund and Emergency Management Division Director Bob Jurgens. “Recent field work by EPA has identified the Ameren Huster Road Substation as the source of newly found contamination in the Elm Point Wellfield. EPA will work with Ameren to ensure that they address the contamination quickly and protect drinking water for St. Charles residents.”

EPA sampled the Elm Point Wellfield between Jan. 17 and 26, using direct push technology to collect groundwater samples from 17 locations at various depths. In addition to collecting groundwater samples, the Agency also collected soil samples at various depths. After collecting the samples, EPA expedited the laboratory analysis as well as the quality assurance/quality control process to ensure rapid delivery of results to the public. EPA has shared the results of the sampling with the city.

EPA will present information on the sampling effort and results at the upcoming Community Meeting scheduled for Feb. 23 at the St. Charles Borromeo Catholic Parish gymnasium. The meeting will begin at 6 p.m. with an availability session, followed by a presentation at 7 p.m. Following the presentation, Agency officials will facilitate a question-and-answer session until 8:30 p.m.

The Ameren Huster Road Substation is Operable Unit 4 (OU4) at the Findett Corp. Superfund Site, and it is an active electrical distribution and transmission substation. It was originally constructed in 1963, and with subsequent expansions now encompasses approximately 8 acres. The substation property contains a control house, three transformers, two capacitor banks, and associated equipment, including a copper grounding grid embedded within crushed limestone. Between 2014 and 2018, Ameren conducted several pilot studies to address contamination at OU4. These pilot studies resulted in contamination remaining confined to the boundaries of the substation.

Additional information regarding the Findett Corp. Superfund Site is available on EPA’s Site Profile page. Read the original article about this tragedy on the EPA Official website.