The Aircraft Components site covers 17 acres in Benton Harbor, Michigan, next to the Paw Paw River. Manufacturing operations there date to the 1910s and included metal furniture production, printing, electroplating, and machining. Starting in 1972, radium-painted aircraft gauges were stored at the site, each holding roughly 10 to 15 microcuries of radium, about 100 times the amount allowed in radium-painted timepieces. EPA added the site to the National Priorities List (NPL) in June 1996, and cleanup has since been organized into two separate areas called operable units (OUs).
Seventeen contaminants of concern have been identified. Radium-226 affected buildings, soil, and debris. Chemical contamination includes volatile organic compounds (VOCs) such as trichloroethene, tetrachloroethene, vinyl chloride, and 1,1-dichloroethene in groundwater. Soil contains arsenic, lead, mercury, selenium, benzo(a)pyrene, and alpha-chlordane. Lead and mercury are also found in sediment, and methane appears in soil gas. These contaminants pose risks through ingestion, skin contact, or inhalation.
EPA tackled radiation first. That cleanup, which involved demolishing contaminated buildings and removing affected soil, was completed in April 2003 and allowed unrestricted use of that portion of the site. For chemical contamination, EPA excavated contaminated soil and river sediment, and injected chemical compounds into the groundwater in December 2007, February 2008, and January 2014 to break down the VOCs. A final remedial action ran from January 2014 to May 2021. In August 2023, EPA approved a partial deletion of the radiation portion from the NPL. The chemical operable unit remains on the list, with groundwater treatment and monitoring continuing until all regulatory standards are met.
Human exposure across the entire site is currently under control, with no unacceptable exposure pathways identified. Contaminated groundwater has stabilized within the original area and is not discharging unacceptably to surface water. Monitoring wells at the site boundary meet drinking water standards. EPA monitors groundwater and soil gas twice a year and surface water once a year. A Restrictive Covenant recorded in May 2012 limits residential use on three parcels, prohibits basements and soil disturbance below 12 inches on two of them unless a vapor barrier is installed, and bans groundwater use until cleanup standards are met. The site is not yet fully ready for all anticipated future uses, and the next five-year review is estimated between July and September 2028. Full reuse is expected between March and May 2026.
The site already supports some productive use. A golf course operates on part of the property, and a warehouse was built in 2017 on the northern portion in line with site requirements. As of December 2024, two businesses operated on-site. Community members can review public records at the Benton Harbor Public Library at 213 E Wall St. For questions about cleanup progress or community involvement, contact the EPA staff assigned to the site.
