Record of Decision Signed

INTRODUCTION

The U.S. Environmental Protection Agency (EPA) Region 7 issued the Record of Decision on Sept. 28, 2020, for the PCE Former Dry Cleaner Superfund Site, Operable Unit 1, located in Atlantic, Cass County, Iowa.

SELECTED REMEDY

The overall strategy of the selected remedy is to continue operating the Groundwater Extraction and Treatment System (GETS). The GETS will remove the contamination from the groundwater.

The selected remedy also includes institutional controls (ICs), which consist of legal or administrative actions or requirements imposed on the property to minimize the potential for human exposure to contamination or to protect the integrity of remediation.

The ICs consist of a city ordinance prohibiting the installation of private drinking water and non-drinking water wells within city limits. The ICs will prevent the ingestion of contaminated groundwater.

Routine groundwater monitoring will also be conducted on a semi-annual basis to evaluate the performance of the GETS and measure the stability of the contaminant plume.

The objective of the selected remedy is to restore the aquifer to beneficial use (i.e., drinking water use) by cleaning up groundwater below maximum contaminant levels (MCLs) in a reasonable time frame. The cleanup levels are based on the Safe Drinking Water Act MCL of 5 micrograms per liter (µg/L) for both contaminants of concern, tetrachloroethylene (PCE) and trichloroethylene (TCE).

ABOUT THE CONTAMINATION

PCE is a nonflammable colorless liquid, used as a dry-cleaning agent and metal degreasing solvent. It is also used as a starting material (building block) for making other chemicals and is used in some consumer products.

TCE is a highly volatile compound that is nonflammable and is a breakdown product of PCE. It is a colorless liquid with a somewhat sweet odor. TCE is used mainly to degrease metal parts, but it is also an ingredient in adhesives, paint removers, typewriter correction fluids, and spot removers.

For additional information about these contaminants of concern, please visit these Agency for Toxic Substances & Disease Registry websites: ToxFAQs™ and TOXZINE (PCE) and ToxFAQs™ (TCE).

BACKGROUND

The site was discovered in 1982 when the Iowa Department of Natural Resources (IDNR) was conducting a water quality survey and discovered PCE in Atlantic Municipal Utility Well-7 (AMU-7) at 170 µg/L.

Contamination detected in the municipal well was traced back to the former Norge Dry Cleaning Village, which was located at 1205 E. 7th Street. Historic use of the solvents PCE and TCE were common in dry-cleaning operations. The operations at the former dry cleaner resulted in releases of PCE to the soils in the area. The PCE leached from the soil to the water table, where it impacted groundwater and migrated in the general direction of groundwater flow, to the north toward the AMU public water supply wellfield.

The EPA Superfund program manages this project as a fund-lead site. Fund-lead sites are funded and managed directly by EPA because viable responsible parties have not been identified to perform the work.

COMMUNITY INVOLVEMENT

Between 2016 and 2019, EPA held public availability sessions and community meetings to present status updates and provide current sampling data and results to the community.

EPA and IDNR will continue to provide information regarding site activities to the public through the Administrative Record file for the site and announcements published in The Atlantic News Telegraph newspaper.

ADDITIONAL INFORMATION

EPA has assessed the ability of the public to access information about the site, including its Administrative Record file, through an internet-based repository and has determined that the local community has this ability. For additional site information, please visit EPA’s website.

EPA CONTACT INFORMATION

If you have questions or need additional information, please contact: