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Site Contact:
Eric Nold


Site Location:
810 East South Street
Marengo, IA 52301

EPA Region 7 received a Request for Federal Action from the Iowa Department of Natural Resources (IDNR) on Tuesday, April 25, 2023.

The EPA Region 7 Superfund Program had closely monitored the C6-Zero site and was in close coordination with IDNR leading up to the request. EPA Region 7 acknowledged receipt of the request on the same day and began transitioning oversight responsibilities.

EPA has engaged with the facility operator and property owner under its Comprehensive Environmental Response, Compensation, and Liability Act (Superfund) authorities. Through CERCLA and the Superfund process, EPA Region 7 On-Scene Coordinators (OSCs) worked with facility response personnel on-site, as well as IDNR, to ensure cleanup operations performed at the property are protective of human health and the environment. 

C6-Zero, through their contractor, shipped liquid wastes to a facility near Harper, Kansas, that is approved for Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Off-Site Rule disposals of non-hazardous waste.  Disposal of all liquids generated was completed by November 3, 2023.

October 11 was the target date for response-generated waste to be disposed of under EPA’s oversight. Disposal of all contaminated soils/solids was completed by November 2, 2023 at the Iowa County Landfill.  After disposal was completed, an additional removal assessment was initiated on November 13, 2023  to determine if any additional work is needed at the site.

The Iowa Department of Natura Resources (IDNR) completed the treatment of over 13 million gallons of water from the stormwater basin in February and March 2023.

EPA Region 7’s Enforcement and Compliance Assurance Division is continuing the investigation into C6-Zero. EPA does not comment on ongoing investigations.