Jump to main content.


Congressional District # 01


EPA ID# MID980794408
Last Updated: March, 2011

Site Description

The Hedblum Industries site is situated on 10 acres within a mixed-use, industrial and residential area in Au Sable Township, Iosco County, Michigan. From 1958 through 1985, the site was leased to a series of industrial firms that manufactured automobile parts. The Hedblum Industries site first came to the attention of the Michigan Department of Environmental Quality (MDEQ) Water Quality Division, during a routine inspection of the facility in 1972. At that time, Thompson Industries was on site property and engaged in the assembly of anti-rattling devices for the automotive industry. Cooling and rinse waters were discharged from the plant directly onto the ground. During another inspection, MDEQ was informed that every two weeks from 1968 to 1972, Thompson had dumped approximately 40 gallons of trichloroethylene (TCE) from a degreasing tank onto the ground. The state estimates that 4,000 gallons of TCE were dumped over this four-year period. Samples from several residential wells indicated that two of them were contaminated with TCE. As a result, the state recommended that local residents not use their wells. The affected residents replaced their contaminated wells with deeper ones in an attempt to tap an uncontaminated water supply. Two more wells found to be contaminated in the Au Sable Heights area in 1975 were also replaced with deeper wells.

In 1977, the local health department received a complaint about a strong odor from one of the replacement wells. Sampling indicated that the well had also become contaminated with TCE. By 1978, the city of Oscoda had extended water mains into the Au Sable Heights subdivision and began providing an alternate water supply to the subdivision. Some property owners in the subdivision elected not to be connected to the Oscoda water system. The Oscoda County Health Department continued to assess conditions at the site and sampled liquids contained in an underground storage tank near the northeastern side of the site in 1980. Upon finding TCE and other solvents, the tank was removed.

In 1981, the state installed seven monitoring wells, determined that the groundwater flow beneath the site was to the northeast, and confirmed solvent contamination. In 1985, the Hedblum Industries property was purchased by Aircraft Tool Supply, which currently produces aircraft parts at the site. About 13,700 people live in the greater area. The closest residence is about 350 feet from the site. An industrial park is located less than one mile north of the site. Most of the Oscoda and Au Sable township populations (about 9,500 people) live within a three-mile radius of the site.

Site Responsibility

This site is being addressed through potentially responsible parties' actions under federal enforcement actions.  Potentially Responsible Parties (PRP) are parties whom EPA has determined may be legally responsible for the site's contamination.

Threats and Contaminants

Groundwater and soil are contaminated with volatile organic compounds (VOCs), including TCE. Surface waters of the bayou northeast of the Au Sable Heights subdivision show low levels of VOCs, including TCE and vinyl chloride. 

A sampling of residential wells in 1990 found no VOC contaminants above detection limits. Onsite groundwater flows northeast toward the bayou.

Cleanup Progress

After a careful evaluation of several alternatives, the United States Environmental Protection Agency (U.S. EPA) explained how the site contamination would be addressed in the the September 29, 1989 Record of Decision (ROD), a public document that explains cleanup alternatives. The remedial action (RA) included: extraction, treatment, and monitoring of contaminated groundwater in the Au Sable Heights subdivision; abandonment of six older groundwater monitoring wells; and collection and analysis of onsite soil samples. A PRP, under a federal enforcement action, completed the groundwater treatment system design in 1992. The construction of the groundwater treatment system was also completed that same year. To date, approximately 284-billion gallons of contaminated groundwater have been treated. While treatment is taking place, the U.S. EPA and MDEQ, now known as the Michigan Department of Natural resources and Environment (MDNRE) are currently working with the PRP to ensure compliance with the enforcement action so that the groundwater plume is effectively captured.

The first five-year review was completed September 30, 1999. The purpose of five-year reviews is to determine whether the remedy at a site still protects human health and the environment. Five-year reviews identify issues or deficiencies found during the review process for the site, and provide recommendations to address or correct them. The methods, findings, and conclusions of the review are documented in the five-year review report. The review determined that although the site remedy was protective, the RA was not being performed effectively, thus requiring more than the projected five years to restore the groundwater.

In September 2004, U.S. EPA completed the second five-year review for the Hedblum Industries site. As part of this process, U.S. EPA and MDEQ reviewed all groundwater monitoring data collected under the operation and maintenance (O&M) program in order to evaluate the current Site status. The September 2004 five-year review concluded that further investigation, such as vertical aquifer sampling (VAS), was needed to better define the plume and to evaluate the need for expanding the RA groundwater extraction system. Thus, a determination of whether the remedy was protective of human health and the environment was deferred to a later time.

The VAS investigation and studies to optimize the groundwater extraction system were performed by MDEQ during summer 2005. In coordination with U.S. EPA, an investigation report was released in November 2005 indicating that the existing RA was not capturing the plume effectively, and that the groundwater extraction and treatment system must be expanded and operated more effectively. Additional data collection was independently performed in 2005 and 2006 by MDEQ and the PRPs. The sampling included the private wells of those residents still using the wells for drinking water or other purposes. To date, only one resident voluntarily uses a private well for drinking and other household needs. Recent information indicates that the occupants of this residence are not exposed to groundwater contamination since the residence lies outside of the plume. A few residents use a private well solely for outdoor activities. All residents were notified and advised to discontinue use of these wells. 

As a result of the 2004 five-year review and subsequent data collection activities, the PRPs submitted a proposal to U.S. EPA to expand the groundwater cleanup and to improve the O&M of the existing pump-and-treat system. The U.S. EPA, in consultation with MDNRE, concurred with the proposal and issued an administrative order in June 2009.  Under the order, an amended scope of work now includes the installation and operation of 24 groundwater recirculation wells and three soil vapor extraction (SVE) wells.  The proposed technology combines in-well air stripping, air sparge, and SVE within each of the 24 wells. As successfully demonstrated at similar sites, it is anticipated that this technology will greatly reduce the time to clean up the aquifer as well as long-term dependency on the current pump-and-treat system.

U.S. EPA issued a third five-year review in August 2009. The review found the remedy to be protective of human health and the environment in the short term. In order for the remedy to be protective in the long term, the groundwater pump-and-treat system must meet the groundwater cleanup goals. In the interim, the institutional controls (ICs) specified by the April 2009 Explanation of Significant differences (ESD) affords protection of human health and the environment by restricting exposure to groundwater.  

U.S. EPA plans to approve the final design of the expanded remedy shortly. Installation of the expanded remedy is expected to begin in Spring 2011. 

Community Involvement

The Au Sable township utilities superintendant has been working with U.S. EPA and MDNRE to identify residences with service connections to the municipal supply and to track the use of private wells in the Au Sable Heights subdivision.

Property Reuse

The 1989 ROD did not require controls prohibiting groundwater use beneath the site property or other areas where the contaminated groundwater has migrated. U.S. EPA issued an ESD in April 2009 that adopted ICs as part of the remedy to ensure protectiveness until groundwater cleanup goals are met. There are no property reuse issues at this time.


Remedial Project Manager, U.S. EPA
sheila sullivan (sullivan.sheila@epa.gov)
(312) 886-5251

Community Involvement Coordinator, U.S. EPA
cheryl allen
(312) 353-6196

Site Profile Information

This profile provides you with information on EPA's cleanup progress at this Superfund site.


Local Navigation

Jump to main content.