Oakland County/Walled Lake-Novi PFAS Evaluation and Source Tracking

Proactive Project Helps Identify Wastewater PFAS Sources, Protect Rouge River Water Quality and Public Health

In a second project partnering with the Oakland County Water Resources Commissioner (WRC) on potential contaminant evaluation in wastewater, OHM Advisors assisted WRC and the Walled Lake-Novi Wastewater Treatment Plant (WL-N WWTP) in going above and beyond Michigan state water quality standards to keep per- and polyfluoroalkyl substances (PFAS) out of the Rouge River watershed. 

Man-made PFAS chemicals have been used globally in the last century in manufacturing, firefighting and in thousands of industrial and consumer products. The chemicals bioaccumulate, break down slowly, move easily throughout the water cycle and have been linked to adverse health effects. In 2017, a section of Michigan’s Department of Environmental Energy and Great Lakes (EGLE) began to investigate PFAS sources and protect drinking water and public health.

In 2018, the state began requiring WWTPs with Industrial Pretreatment Programs (IPPs) to determine if they were passing PFAS compounds to surface waters, evaluate potential sources, investigate probable sources and reduce or eliminate them. The WL-N WWTP does not have an IPP and was not required to comply, but WRC and the Walled Lake and Novi communities chose to conduct a voluntary in-depth study to determine if PFAS compounds were being discharged to the plant’s collection system and passing through to the effluent and biosolids. 

Our team analyzed sampling data taken from locations throughout the collection system and within the WWTP and found that most sample results were well below regulatory standards. The few found to exceed water quality standards were pinpointed via source tracking to stem from industrial discharge facilities which will undergo additional monitoring and work with WRC to reach compliance. The WWTP effluent concentrations sampled were well below PFAS water quality standards during all sampling events and all biosolids concentrations were well within EGLE interim standards for land application. This forward-thinking evaluation has demonstrated that the Michigan PFAS standards are being met and public health and water quality in the Rouge River are being protected.

Project Highlights: environmental engineering, water quality monitoring, PFAS evaluation, PFAS source tracking