EPA Grants Ameren an Extension to Submit Draft Focused Feasibility Study for Huster Road Substation in St. Charles, Missouri
The extension provides Ameren an additional two weeks – until July 17 – to complete the draft study

U.S. Environmental Protection Agency, Region 7 - 11201 Renner Blvd., Lenexa, KS 66219

Iowa, Kansas, Missouri, Nebraska, and Nine Tribal Nations

Contact Information: Kellen Ashford, ashford.kellen@epa.gov, 816-610-2132

LENEXA, KAN. (JUNE 29, 2023) – Today, the U.S. Environmental Protection Agency (EPA) Region 7 granted Ameren a two-week extension to complete a draft Focused Feasibility Study (FFS) for the Huster Road Substation in St. Charles, Missouri.

Ameren now has until July 17, 2023, to provide EPA with the draft FFS. The original deadline for the FFS was June 30. EPA has notified the city of St. Charles and will continue to keep them informed on progress at the site.

This two-week extension ensures that the FFS received by the Agency will have additional data needed to provide a detailed analysis of cleanup options to establish the basis for remedy selection decisions that will be made by EPA.

“EPA is providing oversight of Ameren’s work at the Findett Corp. Superfund Site to assure that it meets the requirements set forth by Superfund,” said EPA Region 7 Superfund and Emergency Management Division Acting Director Scott Hayes. “Providing Ameren this extension helps to make sure that the work performed by Ameren is exhaustive and methodical to ensure protectiveness of human health and the environment.”

EPA examined Ameren’s extension request thoroughly and granted the two-week extension for several reasons. Since February 2023, EPA has directed Ameren to:

  • Complete a performance monitoring plan for the zero-valent, iron permeable reactive barriers, which have been installed to break down contaminants as they pass through them.
  • Complete a site characterization plan to further define the contaminated groundwater plume.
  • Update the conceptual site model (CSM), which is a representation of a site that summarizes and helps project teams visualize and understand available information.
  • Complete a comprehensive groundwater monitoring plan for historical and new monitoring wells within the Elm Point Wellfield; and,
  • Complete a revised quality assurance project plan (QAPP).

EPA also considered the May 5, 2023 finalization of an access agreement for the Elm Point Wellfield between Ameren and the city in approving Ameren’s request for an extension.

For additional information regarding the Findett Corp. Superfund Site and Ameren Huster Road Substation (Operable Unit 4), please visit EPA’s Site Profile page.

# # #

Learn more about EPA Region 7