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Lear Siegler Inc. (Mendon, St. Joseph County)
Please contact the Site Lead for the most up-to-date status of this site.
This automotive accessory manufacturer is located at 236 West Clark Street in Mendon. Plastic molding began at this facility in 1932 and operations were expanded to include plastic plating, trim and fabric preparation, and parts assembly, when Lear Siegler acquired the site in 1970. Industrial wastes were historically disposed on site. Lear operations were purchased by International Automotive Components (IAC) in 2007 and they have been conducting response activities for contaminants other than PFAS at the site. IAC submitted a No Further Action request to the Michigan Department of Environment, Great Lakes, and Energy (EGLE) in January 2018. IAC Mendon has not used PFAS during its operations. EGLE requested IAC sample for PFAS based on the history of the site that included a plating line until 1985. Testing by IAC confirmed PFAS in the on-site and off-site groundwater in 2019.
Groundwater flow in the area is southerly.
Content posted May 2021.
Most area residents utilize municipal water. According to local records, there are approximately 12 private residential wells still being used in Mendon. Three municipal water supply wells are about 1,000 feet southeast and southwest downgradient of the site. The Mendon municipal water supply was sampled in October 2018 and was Non-Detect for PFOS+PFOA and Non-Detect for Total Tested PFAS. EGLE has tested all municipal water supplies for PFAS. View the results for the village of Mendon.
IAC will discuss the results of this report and possible next steps, with EGLE in a meeting early in 2021, following review of the report and this meeting has yet to be scheduled.
- On October 16, 2018, at the request of EGLE, IAC collected samples from six groundwater monitoring wells
- On April 24, 2019, IAC shared the October 2018 groundwater sampling results with EGLE. Four on-site monitoring wells detected PFAS above the standard, and the highest result was 1,312 ppt PFOS+PFOA and 1,334 ppt Total Tested PFAS.
- On May 21, 2019, EGLE resampled the individual municipal water supply wells that are ¼ mile away from the site. A sample was also taken from the village water tank. This testing and prior testing in October 2018 found no PFAS compounds.
- EGLE shared results from the May 21, 2019 sampling with municipal officials and they have been posted online.
- On June 6, 2019, EGLE met with IAC Mendon to request they confirm the initial on-site groundwater results. EGLE also requested they sample additional on-site and downgradient off-site monitoring wells to help determine the extent of the contamination and whether it has migrated off-site. In addition, EGLE requested a survey of the area be conducted for potential undocumented private water wells.
- On August 5, 2019, IAC submitted a sampling plan for EGLE review. On August 7, 2019 EGLE approved this plan.
- On November 11, 2019, consultants for IAC submitted a report summarizing the August groundwater sampling. This sampling confirmed PFOS/PFOA contamination in the groundwater at the facility. Total PFOS/PFOA exceeding the drinking water criteria was detected in two downgradient, off-site monitor wells. IAC and the Village of Mendon identified two residential water supply wells immediately downgradient of the identified contamination.
- On November 15, EGLE requested IAC test the two residential water supply wells immediately downgradient of the site for PFOA/PFOS and IAC cannot do this expeditiously because of lack of legal access. EGLE will attempt to obtain access and test these wells as soon as practical.
- On December 2, 2019, EGLE contractors sampled two residential wells in Mendon. EGLE was unable to contact several occupants to access their wells for testing. Many of the dwellings with private wells currently sit vacant.
- On December 6, 2019, IAC announced plans to discontinue manufacturing operations in Mendon in May 2020. A new equipment order will allow the plant to continue operating until 2021.
- On December 12, 2019, IAC requested a meeting by telephone to discuss next steps in Mendon. IAC plans to continue to define the extent of PFAS contamination.
- In December 2019 - January 2020, EGLE contractors sampled 12 residential water supply wells. Water samples were submitted to the EGLE Laboratory for analyses.
- On January 11, 2020, EGLE received the sample results. The analyses detected PFAS contamination in 4 samples at concentrations below criteria.
- On January 16, 2020, an IAC representative affirmed IAC's willingness to reimburse costs to the village for a municipal water supply replacement needed to address the contaminant situation at a village residence. Other water supply wells in the township contaminated with PFAS compounds are upgradient of the site and the source of this PFAS contamination is undefined.
- In February 2020, IAC assisted the village in supplying one resident with municipal water. The local health department is working with one township resident to have a tap filter installed.
- A public meeting to discuss PFAS in the drinking water scheduled for March 25, 2020 was postponed and will be rescheduled at a future date. An informational flier summarizing site conditions was distributed with the municipal water bills to village residents on March 31, 2020.
- In July 2020, IAC submitted a draft work plan for EGLE review, EGLE provided comments and approval to proceed in August. IAC has addressed funding issues caused by the pandemic so work can proceed.
- In October 2020, IAC installed and sampled three monitor wells to further evaluate the extent of PFAS contamination. IAC additionally sampled seven existing monitor wells to confirm 2019 sample analyses results.
- In December 2020, EGLE received a report summarizing the results from the October 2020 sampling event. Seven groundwater samples exceed drinking water criteria. The highest result was 1,000 ppt PFOS collected from monitoring well OW-18.
- In March 2021, IAC submitted a report summarizing the results of its October 2020 groundwater sampling event, including the newly installed downgradient monitor wells.
Sampling Results Summary
This chart reflects data received after 8/3/2020. Data prior to 8/3/2020 is reflected in the timeline below.
Type of Sample
Date Sampled (or Range)
Numberof Sample Results Received
Number of Samples above Criteria*
Groundwater Monitoring Wells
October 2020 13 8
- 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 sampling data
Data is reflective of criteria prior to 8/3/2020. PFOS and PFOA Only
This chart reflects data received prior to 8/3/2020.
Type of Sample
Date Sampled (or Range)
Number of Results Received
|Number of Non-Detects
|Number Between Non-detect and Standard*
|Number Greater Than or Equal to Standard
Drinking Water (Residential Wells)
|December 2019 - present
|October 2018 - present
*Groundwater results are compared to EGLE Part 201 Criteria of 70 ppt PFOS+PFOA. Residential well results are compared to the EPA LHA of 70 ppt PFOS+PFOA.