Significant Efforts Continue to Characterize, Monitor, and Remediate Groundwater including PFAS
Groundwater remediation has been ongoing at Central Sanitary Landfill (CSL) under a Remedial Action Plan approved by the State. The remediation addresses groundwater releases from an old, unlined landfill formerly operated by others. The materials in the unlined landfill were removed and placed in the modern, lined landfill cells at the site in 1992 as part of the remedial actions. CSL has since assumed responsibility for the remediation by operating a system since the 1990s that pumps and treats groundwater. Extensive groundwater testing at the site is also completed quarterly under an approved plan and the results are submitted to the Michigan Department of Environment, Great Lakes and Energy (EGLE) for review.
Monitoring for certain chemicals known as Per- and polyfluoroalkyl substances (PFAS) began across Michigan in recent years. Testing of groundwater for PFAS at CSL began in 2018 and detections were observed in monitoring wells at the landfill property. This led to testing of water supply wells in the surrounding areas in several phases starting in 2018.
The landfill and multiple state and local agencies held an open house and public meeting in June 2018 to share the Phase 1 sampling results and answer the community’s questions. Following that meeting, we conducted additional Phases of groundwater testing in 2018 at properties located near the landfill. The 2018 results indicated that there were no detections for the PFAS compounds above the drinking water health advisories in place at the time. However, properties with detections were offered filtration systems by CSL or the Michigan Department of Health and Human Services (DHHS) as a conservative measure.
CSL collected another round of samples in April 2022 from the previously sampled water well supplies for analysis of PFAS. EGLE established first-time drinking water standards for seven PFAS chemicals in 2020. The 2022 sampling was conducted to compare to the past results and new standards and to allow DHHS to continue to be able to advise neighbors on use of the water including possible filtration recommendations. The sampling continued to be completed in close coordination with EGLE and DHHS. Most locations continued to show no detections or no exceedances in 2022. A few samples showed exceedances of the new standards for one or two compounds at locations that were previously offered filtration.
Since 2018, we continue installing additional monitoring wells between the landfill and neighbors to further investigate the extent of the groundwater migration. We also installed an expanded groundwater pumping and treatment system at the landfill. CSL will continue to work with EGLE to complete the needed studies.
The Central Sanitary Landfill team remains committed to being a good neighbor and responsible operator. For questions about PFAS sampling or the Landfill, please contact us at centralsanitary@republicservices.com.