Site investigations get started for a variety of reasons. At some sites, like Superfund sites, EGLE staff have been overseeing environmental cleanup efforts for many years, and may add PFAS sampling to ongoing sampling if PFAS was known or suspected to have been used at the site. EGLE staff also conduct routine monitoring of rivers and lakes, and if a sample exceeds water quality standards, staff work upstream until they find the site contributing to the PFAS. Other sites were sampled due to historical information, such as Carl’s Retreading, which was where tires burned for many days and firefighting foam containing PFAS was used. EGLE is committed to continuing to do all of these types of sampling efforts.
On August 3, 2020, the groundwater cleanup criteria became 8 ppt PFOA and 16 ppt PFOS. On December 21, 2020, the following 5 additional PFAS compounds became groundwater cleanup criteria: PFNA (6 ppt), PFHxS (51 ppt), PFHxA (400,000 ppt), PFBS (420 ppt), and HFPO-DA (370 ppt). EGLE staff use all 7 PFAS criteria to guide groundwater investigations, protect public health, and identify MPART PFAS sites.