Announcing the Fourth Five-Year Review Report for the Des Moines TCE Superfund Site, Polk County, Iowa
The U.S. Environmental Protection Agency (EPA) conducts regular checkups, called five-year reviews, on Superfund sites where cleanups are in progress or have been completed. These reviews are required by the Superfund law [42 U.S.C. Section 9621 (c)]. EPA Region 7 has completed the fourth five-year review of the Des Moines TCE Superfund Site in Des Moines, Polk County, Iowa.
In the mid-1970s, EPA responded to findings by the city of Des Moines and the state of Iowa that there were volatile organic compounds (VOCs) in the Des Moines water supply.
EPA investigations showed that the property owned by Dico, Inc. was the primary source of the VOC contamination. Dico manufactured steel wheels on the property starting in the mid-1940s. As part of its manufacturing process, Dico used industrial solvents, including trichloroethylene, known as TCE.
To clean up the contaminated ground water, a treatment system was installed in 1987. The treatment system includes ground water extraction wells, an on-site treatment system and monitoring wells. Dico continues to operate and maintain the treatment system.
From the mid-1950s to the early 1970s, pesticide and herbicide products were formulated on the property owned by Dico, Inc. Investigations conducted by Dico and EPA determined that these operations left residual contamination in several buildings and outside soils. Contaminants found in the buildings and in the adjacent soils included aldrin, dieldrin, heptachlor, chlordane, 2,4-D, 2,4,5-T and polychlorinated biphenyls (PCBs).
A series of cleanup actions was conducted in the mid-1990s to address contamination in surface soils and buildings. Dico placed an asphalt cap over much of its property to prevent exposure to contaminated soils and cleaned and coated surfaces in several buildings to prevent exposure to contamination. The cap and coatings require long term maintenance to ensure they remain effective. Dico currently provides the required maintenance.
Also in the mid-1990s, a group of other potentially responsible parties excavated pesticide contaminated soils from a drainage ditch adjacent to the Dico property and from the South Pond Area on the Dico property. These soils were taken to an offsite disposal facility.
During this five-year review the site was inspected and there was a review of the site records developed over the past five years. The conclusion of this fourth five-year review is that the cleanup actions in place at the site remain protective of human health and the environment for the current land use.
During this site inspection, it was discovered that some buildings on the Dico property had been dismantled and other buildings were in the process of being dismantled. These buildings were included in earlier cleanup actions and their long-term maintenance was part of the remedial action selected for this site. While dismantling these buildings may have presented some short-term risks to the workers, it is not believed to affect the long-term integrity of the remedial actions at the site. The EPA is communicating with the site owner and others involved in the dismantling of the buildings to ensure the long term protection of human health and the environment.
The site administrative record is available at the following locations during normal business hours:
EPA Records Center
901 N. Fifth St.
Kansas City, Kan.
Des Moines Public Library
1000 Grand Ave.
Des Moines, Iowa
Questions or requests for information can be submitted to:
Community Involvement Coordinator
7901 N. Fifth St.
Kansas City, KS
Toll free: (800) 223-0425