Record of Decision for Remedial Action - Railroad Avenue Superfund Site
Northern Plume, West Des Moines, Iowa
The U.S. Environmental Protection Agency (EPA) has signed a Record of Decision (ROD) for a Remedial Action that addresses ground water contamination by hazardous substances in the Northern Plume of the aquifer at the Railroad Avenue site in West Des Moines, Iowa. This action is being taken under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA), also known as the Superfund law. The ROD was signed on September 19, 2005.
The EPA estimates there are currently no significant risks presented by the site. However, significant potential future risks exist, based on assumptions of individual well water use from the contaminated area.
EPA received public comments on the Proposed Plan at a public meeting and through written submissions. Although EPA and the Iowa Department of Natural Resources (IDNR) recommended the proposed action to address the contamination, a final decision was not made until EPA reviewed comments from the public. After the comment period closed, EPA selected a remedy and published a Record of Decision (ROD). The ROD includes EPA’s remedy selection and a summary of EPA's responses to the comments received during the public comment period.
ABOUT THE CONTAMINATION
The contamination at this site consists of tetrachloroethene (PCE); trichloroethene (TCE); cis-1,2-dichloroethene (cis-1,2-DCE); and vinyl chloride (VC). Several potential source areas for the Northern Plume were investigated; however, a specific source area for the Northern Plume was not identified.
EPA's selected remedy will use Monitored Natural Attenuation to address the remaining threats at the site. The major components of the selected remedy for ground water include:
- Institutional Controls - including seeking city well permitting requirements or a protected water source designation and public education. These institutional controls will minimize potential health risks associated with ground water contaminants still undergoing attenuation
- Monitored Natural Attenuation - would rely on the aquifer's ability to lower contaminant concentrations through monitored natural attenuation processes. This alternative includes ground water and surface water monitoring, to confirm continued efficiency of the natural attenuation of contaminants.
Implementation of this Alternative would be performed simultaneously with the previous interim Remedial Action that included expansion of the treatment capacity at the WDM water plant. The interim remedy addressed only a portion of the northern West Des Moines well field area. Based on additional investigations, monitoring of the impact of the pumping under the interim ROD, and a Feasibility Study, this ROD addresses the final remedy for the rest of the Northern Plume
The Record of Decision and other site-related documents provide details of the nature and extent of contamination and the work that has been completed at the site. These documents are part of the Administrative Record File, available at the following locations during regular business hours:
West Des Moines Public Library
4000 George M. Mills Civic Parkway
West Des Moines, Iowa
EPA Region 7
901 N. 5th Street
Kansas City, Kansas
If you have questions or need additional information, please contact:
Community Involvement Coordinator
EPA, Region 7, Office of External Programs
901 North 5th Street
Kansas City, Kansas 66101