Skip to main content

Thermofil (Green Oaks Township, Livingston County)

Web content may not routinely be updated on this page. Please contact the Site Lead for the most up-to-date status of the site.
Content posted May 2021.

EGLE Site Lead

Emily Peabody, or 517-388-5719.


The property was developed in 1955 by Haigh Manufacturing Company as a metal stamping operation. From 1977-1982 the site was occupied by ITT-United Plastics, which molded and painted plastics. Thermofil purchased the facility from ITT in 1982 and operated a custom reinforced plastic compounding business. During process operations, a resin was blended on site with agents such as fiberglass, talc, mica and flame-retardants. This blended material was then transformed into pellets. The plastic creation process included the addition of flame-retardants. PFAS is used during the creation of plastics to keep the plastic from sticking to the mold.  In 1997 a large fire occurred, and plastics stored at the facility burned. It is reported only water was used to control the fire. There are no reports of fire-fighting foam being used.

EGLE has conducted previous investigations at the facility and downgradient within a residential area associated with a trichloroethylene (TCE) groundwater contaminant plume extending approximately 2,000 feet in a southeast direction towards the Huron River watershed.

Thermofil Map

Recent Accomplishments

  • On January 5, 2021, EGLE received the analytical results from the December 2020 sampling.  Results indicate soil and groundwater impacts both on and off site.  The highest values detected in groundwater were 790 ppt PFOA, 330 ppt PFOS, and 61 ppt PFHxS at sample point B3 located on the west side of the detention basin.
  • This site is the subject of litigation brought by the Attorney General on behalf of the State of Michigan against Asahi.  The Department of Attorney General, represented by a team of Special Assistant Attorneys General, is in negotiations with Asahi to explore resolution of the litigation in a way that benefits the public and the environment while the case is pending in Livingston County Circuit Court.   

Next Steps

  • EGLE is reviewing the current analytical data to determine what additional actions may be taken.
  • EGLE is awaiting resolution to the Asahi litigation.

Residential Well Testing/Alternate Water Information

  • This site is located within Starlight Mobile Home Park's wellhead protection area. EGLE has tested all municipal water supplies for PFAS. View the results for Starlight Mobile Home Park.
  • The immediate area surrounding the facility is on municipal water supplied by the city of Brighton, however, private wells remaining in the wellhead protection area are outside of the current detection area.

Upcoming Community Engagement

  • None scheduled at this time.

Sampling Results Summary

This table reflects data received after August 3, 2020. Data prior to August 3, 2020 is reflected in the timeline below.

This table was updated to include all seven PFAS criteria effective December 21, 2020.

Type of Sample

Date Sampled (or Range)

Number of Sample Results Received

Number of Samples above Criteria*


December 10 - 11, 2020 12 13


*Residential well and groundwater monitoring well results are compared to EGLE Part 201 criteria for 7 PFAS compounds:  PFOS (16 ppt), PFOA (8 ppt), PFNA (6 ppt), PFHxS (51 ppt), PFHxA (400,000 ppt), PFBS (420 ppt), and HFPO-DA (370 ppt).

Sampling Notes

  • On August 3, 2020, new Part 201 Criteria went into effect.  Historical sampling data compared to Part 201 Criteria >70 is captured in the historical timeline below.
  • Other PFAS analytes were detected in samples. There are no federal or state standards for these analytes.

Historical Timeline

    • On April 16, 2019, EGLE's contractor collected 11 groundwater samples from monitoring wells.
    • On May 13, 2019, EGLE received the results. The highest values were 163 ppt PFOS+PFOA and 294 ppt Total Tested PFAS.
    • On August 27 to September 3, 2019 EGLE's contractor collected 26 groundwater samples from monitoring wells.
    • On October 15, 2019, EGLE received the results. The highest values were 198 ppt PFOS+PFOA and 475 ppt Total Tested PFAS.

      Historical Sampling Chart: Data is reflective of criteria prior to August 3, 2020,  PFOS and PFOA Only

      This chart reflects data received prior to August 3, 2020.

      Type of Sample

      Date Sampled (or Range)

      Number of Samples

      Number of Results Received

      Number of Non-Detects  Number Between Non-detect and Standard*  Number Greater Than or Equal to Standard 


      April 2019 - Present 37 37 13 19 5
       Cumulative   37 37 13 19 5


      *Groundwater results are compared to EGLE Part 201 Criteria of 70 ppt PFOS+PFOA.

    • In September 2020, a new map was generated showing detections of PFAS in groundwater.
    • On October 13, 2020, EGLE approved a work plan to have their contractor, DLZ, conduct PFAS sampling of the storm water detention basin.
    • On December 10-11, 2020, PFAS sampling of the storm water detention basin area was conducted by EGLE's contractor, DLZ. 12 groundwater samples and 24 soil samples were collected and submitted to Fibertec for analysis.