Sylvan Township and neighboring communities are updating the Remedial Action Plan (RAP) for the old landfill on Werkner Road.

At their Aug. 13 meeting, the Sylvan Township Board approved devoting $7,661 for the township’s portion to update the RAP. Sylvan Township was told by letter from the city of Chelsea that they were informed by the Michigan Department of Environment, Great Lakes, and Energy (EGLE) that an update to the 2017 Remedial Action Plan is necessary due to the presence of Per- and Polyfluorinated Substances (PFAS) found through routine groundwater monitoring conducted in 2020.

The Werkner Road site is home to an old landfill. The RAP, which is a cleanup plan, is a shared agreement between Chelsea, Sylvan Township, Lima Township, Lyndon Township and Dexter Township.

The city of Chelsea website describes the location this way:

“At one time, the City of Chelsea maintained an active landfill at the Werkner Solid Waste facility. For that reason, the Solid Waste facility is sometimes still referred to as the ‘landfill’. The City continues to monitor the landfill at the site as required by the Michigan Department of Environmental Quality (MDEQ), however, no additional refuse is deposited to the Werkner Road landfill. The Solid Waste Department is also commonly referred to as the ‘transfer station’ because refuse is collected there then transported to active landfills for final disposition.”

Two parts of the updated RAP will include installation of eight new monitoring wells and installation of sampling equipment.

The estimated costs to update the plan are expected to be shared by Chelsea at $79,450, Dexter Township at $11,917, Sylvan and Lyndon at $7,661 a piece, and Lima Township at $6,810.

In a letter to Chelsea, Brett Coulter, the District Geologist of the Materials Management Division for EGLE, said they reviewed the RAP, dated June 2017, for the Werkner Road Landfill, as well as recent groundwater monitoring data and PFAS reports for PFAS activities conducted in 2020.

He said based on the results there is a need to update the 2017 RAP, and in addition to the recommendations already in it, the following should also be included in the plan:

• Sampling of all onsite monitoring wells and the onsite drinking water well for volatile organics, semi-volatile organics, inorganics and PFAS compounds
• Further evaluation of contamination potentially discharging to wetland areas adjacent to the landfill through sampling and additional monitoring points
• Further assessment of the migration of contamination beyond property boundaries
• An assessment of the leachate collection system
• An updated conceptual site model

Coulter said while PFAS investigations onsite have provided some definition of the nature and extent of contaminates on the landfill property, additional delineation is required to adequately define the extent of PFAS.

About this site, the EGLE webpage said:

“Werkner Road Landfill is a solid waste facility located at 8027 Werkner Road. PFAS testing was conducted due to an MPART landfill initiative. PFAS samples were collected from six monitor wells and a leachate pond. One monitor well sample exceeded the EGLE criteria for PFOA (MW-2S), and a duplicate sample (MW-4 Dup) also exceeded the criteria for PFOA. The highest PFOA result was 54 ppt. The leachate pond is located near the center of the landfill property, and the leachate is pumped out of the pond and disposed of as needed.”

“Groundwater flow is typically to the east-northeast and is consistent with local topography. Ground elevations are higher to the north and west, with low areas to the northeast and east of the landfill property. Wetlands are located adjacent to the landfill to the south, east, and northeast. West Lake is located to the east-northeast and approximately 2,000 feet from the east boarder of the landfill property. Because the contamination is shallow and nearby residential wells are side-gradient and up-gradient and screened at a deeper depth, residential wells are unlikely to be impacted.”

EGLE staff is recommending quarterly PFAS monitoring and that the monitoring be included in the site remedial action plan.