The Hedblum Industries site covers 10 acres in AuSable Township near Oscoda, Michigan. Automobile parts manufacturers operated there from 1958 to 1985 and left behind chlorinated chemical contamination in soil and groundwater. EPA added the site to the National Priorities List (NPL) in September 1983. The NPL is the federal government's list of the most serious uncontrolled or abandoned hazardous waste sites. Cleanup work began in the early 1990s and is still active today under long-term oversight.
Seven chlorinated compounds have been identified in groundwater at the site: 1,1,1-trichloroethane, 1,1-dichloroethane, 1,1-dichloroethene, cis-1,2-dichloroethene, tetrachloroethene, trans-1,2-dichloroethene, and trichloroethene. These are volatile organic compounds (VOCs), chemicals commonly used as industrial solvents that can turn to vapor in air. Contaminated soil on the property has been removed. The remaining concern is groundwater contamination and the risk of vapor intrusion, which happens when VOCs seep up through foundation cracks into buildings.
The active cleanup system includes 23 circulation wells installed on-site and in the nearby AuSable Heights subdivision since 2012, plus three soil vapor wells that prevent gases from entering homes. Treated water discharged to the AuSable River is sampled monthly. Starting in August 2022, EPA and the Michigan Department of Environment, Great Lakes, and Energy (EGLE) conduct quarterly soil gas sampling at 14 locations. If results exceed screening levels, indoor air will be tested at nearby buildings. Residents in the AuSable Heights subdivision are connected to the township water supply and do not rely on private wells. A 2012 local ordinance bans groundwater use and new well installation for residents downgradient of the site. Zoning and deed restrictions block residential use of the contaminated property itself. An aircraft tool supply company has operated the site since 1985 and currently employs 21 people.
A 2019 five-year review found the remedy protective of human health and the environment in the short term. EPA has determined that human exposure is under control across the entire site, construction is complete, and groundwater migration is stabilized with no unacceptable discharge to surface water. The site holds "sitewide ready for anticipated use" status, meaning cleanup goals have been met for current and expected future land uses. The most recent five-year review was completed in September 2024. The site has not yet been deleted from the NPL.
Community members with questions or concerns can contact the EPA's Community Involvement Coordinator, or the Remedial Project Manager for technical oversight. EGLE also has a state-level project manager for the site.
