EPA Announces Final Decision for Time-Critical Removal Action, Des Moines (ex) Ordnance Plant Superfund Site, Ankeny, Iowa
The U.S. Environmental Protection Agency (EPA) Region 7 has reached a final decision for a Time-Critical Removal Action at the landfill/lagoon complex portion of the Des Moines (ex) Ordnance Plant (DMOP) Superfund Site. Site-related activities are scheduled to begin in the fall of 2008. The clean-up will address contamination that poses a risk to human health and the environment at the landfill/lagoon complex. The public was provided an opportunity to comment on EPA's proposed clean-up actions from May 29 – June 29, 2008.
EPA has documented the clean-up decision and provided a response to citizens' comments in an Action Memorandum and a Responsiveness Summary that can be found in the Administrative Record developed for the Site.
EPA is currently finalizing an agreement with the responsible parties to perform the necessary clean-up work.
OBJECTIVES OF REMOVAL ACTION
As described in the Action Memorandum, the objectives of the Time-Critical Removal Action are as follows:
- Perform groundwater and soil investigations to define the nature and extent of contamination.
- Excavation and off-site disposal of contaminated soils, sediments, and liquids from lagoons that are above health-based levels of concern.
- Prevent direct contact with and ingestion of contaminated soil/landfill contents by constructing an engineered cap.
- Control the landfill surface water runoff and erosion.
- Minimize or prevent the migration of contamination to the groundwater and surface water.
- Implement institutional controls to protect and maintain the landfill cover and restrict land and groundwater uses.
The Clean-up will consist of the following activities:
Groundwater samples will be collected to assess the potential for migration of groundwater flow around the vicinity of the Site. The investigation will also include soil sampling in an 18-20 acre area southwest of Saylor Creek. The landfill will be capped with a multilayer cover system to prevent direct contact with the landfill contents, minimize infiltration and prevent leaching to groundwater, and minimize the migration of contaminants from the source area. A layer of clean topsoil will be placed and seeded over the multilayer cover system to restore the landfill area.
The water will be drained from the lagoons prior to the excavation of impacted areas. The liquids removed will be sampled and disposed of at an appropriate disposal location. Contaminated sediments and surrounding soils from the lagoons will be excavated and disposed of at an appropriate disposal location.
During the course of field work, air sampling will be conducted during critical work phases to ensure protection of the nearby community. Security fencing will be installed around certain contaminated areas of the Site to ensure restricted entry during the clean-up of identified hazardous substances. All phases of the clean-up will be closely monitored by EPA, and the work is anticipated to be completed within six to eight months.
LONG-TERM MONITORING AND INSTITUTIONAL CONTROLS
After the landfill/lagoon complex clean-up is complete, long-term monitoring of the groundwater will be performed. Institutional controls will be placed on the property to further prevent unacceptable exposure to contamination. Specifically, the institutional controls will require the city and future land owners to protect and maintain the landfill cap, prevent installation of drinking water wells, and limit the use of the property for recreational purposes.
EPA invited the public to provide feedback during a public comment period from May 29 – June 29, 2008. On May 29, 2008, EPA hosted a public availability meeting in Ankeny, Iowa, to discuss the environmental threats that are present at the DMOP, and to explain the proposed Time-Critical Removal Action. EPA established an Administrative Record which contains all of the documents that form the basis for the selection of an EPA response action at the DMOP.
EPA has reviewed all of the comments received from the community regarding the DMOP and nearby redevelopment areas. All of the comments submitted during the public comment period were considered in formulating the Time-Critical Removal Action for the DMOP. The public comments received did not disclose any facts or considerations that would indicate EPA's selected clean-up plan is inappropriate.
EPA encourages the community to review the Administrative Record regarding the DMOP for updates on activities related to the Site. All of the documents regarding the DMOP Site are included in the Administrative Record. The Administrative Record is available at the following locations during normal business hours:
Kirkendall Public Library
Attention: Myrna Anderson
1210 N.W. Prairie Ridge Drive
Ankeny, Iowa 50023
EPA Region 7
901 N. Fifth Street
Kansas City, KS 66101
If you have questions or need additional information, contact
Belinda Young at 1-800-223-0425, or by e-mail at email@example.com.