Des Moines TCE

Overview

The Des Moines TCE Superfund site sits in south-central Des Moines, Iowa. Dico Inc. operated the property for about 40 years, manufacturing steel wheels and formulating chemicals and pesticides. Those activities released trichloroethene (TCE), other volatile organic compounds (VOCs), pesticides, polychlorinated biphenyls (PCBs), lead, and dioxins into groundwater, soil, sediment, and site structures. The site was added to the National Priorities List (NPL) in September 1983, and initial cleanup work began in 1984.

Cleanup is organized into four operable units. One unit addresses groundwater at the main DICO area using extraction wells, air stripping, and a slurry wall that have been running since December 1987. A second unit covers source control through institutional controls. A third unit monitors a northern groundwater plume with no further action required. A fourth unit addressed the South Pond and Drainage Area, where pesticide-contaminated sediments were dredged in fall 2022, with removal work completing in May 2023. Contaminated buildings have been demolished, and an asphalt cap covers pesticide-contaminated soils. An optimization study completed in 2018 found the existing groundwater treatment system should be replaced. EPA began that replacement work on November 3, 2025, swapping the 30-foot air stripping tower for a lower-profile unit and installing new extraction wells. The new system is expected to be complete by Spring 2026.

The contaminants of concern in groundwater include TCE, tetrachloroethene, chloroform, and related chlorinated compounds. Soil and sediment in the South Pond area contained aldrin, chlordane, dieldrin, PCBs, and dioxins. Health risks come from drinking contaminated groundwater, direct contact with capped soils, and vapors that could seep into buildings. Groundwater use is prohibited on site, the asphalt cap blocks direct soil contact, and any future enclosed buildings must include vapor barriers. EPA has determined that human exposure is under control and groundwater migration is stabilized.

The city of Des Moines now owns the 43-acre property, which was transferred following a 2020 settlement agreement. The land is governed by an Environmental Covenant that limits use to non-residential, commercial, recreational, or multi-family residential purposes with EPA approval. Single-family homes, daycare facilities, and elder care facilities are prohibited. EPA and the city are working with a developer to evaluate whether the site can support a professional soccer stadium complex. The most recent five-year review was completed in March 2023, with the next review estimated between March and May 2028.

Community members can review site records at the Des Moines City Library Central Library at 1000 Grand Avenue. For questions, contact the EPA Community Involvement Coordinator or the Remedial Project Manager. For state-related questions, contact the Iowa Department of Natural Resources.