The State Water Resources Control Board issued investigative orders on March 11 to over 160 refineries and bulk fuel storage terminals in over 30 California counties, requiring environmental investigation and sampling for per- and polyfluoroalkyl substances, known as "PFAS." This most recent wave of PFAS investigation orders is consistent with California's increasingly aggressive approach to regulating and investigating PFAS in everything from soil, groundwater, food packaging, and consumer products.