Committee reviews USGS groundwater-monitoring contract and proposed PFAS/microplastics study

McHenry County Planning & Development reviewed a USGS contract renewal for the county groundwater-well monitoring network and a proposed two-year study that would re-test wells for PFAS and add microplastics sampling, with staff answering committee questions about scope, cadence and cost.

Adam said the USGS contract would continue the county’s long-standing groundwater monitoring program, which provides near-real-time water-level data and decadal chemical sampling. He described the USGS system as recording data at frequent intervals and making it available on a public website: “They've got every 10 minutes over the last 15 years of groundwater data,” Adam said.

The USGS renewal included a $2,500 annual increase for the county (a $7,500 total request in the current contract cycle), Adam said. A separate slide initially presented a $590,000 cost over two years but was corrected in the discussion: a committee member asked whether that projection covered three years, and Adam confirmed the planned figure was over three years for the multi-year monitoring program.

Staff described an additional two-year study to retest 16 strategically selected wells for PFAS and microplastics and to compare those results to earlier samples. Adam said the initial sample from 2020 predated EPA-approved PFAS testing protocols, and when testing became available in 2022 the follow-up showed results that require validation. He told the committee: “PFAS are are, a forever chemical and they're used in several different things... it has carcinogenic properties to it.” The proposed study would test for PFAS and attempt to identify likely sources (for example, firefighting-training sites or other potential point sources) and would include microplastics analysis.

Committee members asked about sampling details (how frequently data are recorded, what the USGS provides for equipment support and whether the data are publicly accessible). Adam said USGS provides continuous recording and a public interface for the data and that the contract includes maintenance and equipment contingencies. The committee also discussed how the monitoring network helps identify trends and informs local decision-making in stressed areas such as parts of the county with groundwater concerns.

The committee did not take a binding vote at the meeting but acknowledged the monitoring and study items as part of the department’s FY26 supplemental requests and budget planning. Staff noted the monitoring program had been a long-running county initiative and that declining participation could increase future costs if the county needed to bring specialist services in-house.

The committee asked staff to include corrected cost and term information in the budget materials and to provide public access links and a summary of how the monitoring data are used for land-use and public-health planning.