In 1987, California adopted the Air Toxics “Hot Spots” Information and Assessment Act, responding to increasing concern over toxics in the air (AB 2588 (Connelly, Sterling)). This law complements California’s enforcement of national requirements governing stationary source emissions of air toxics. The federal Clean Air Act (CAA) required the U.S. Environmental Protection Agency (EPA) to establish and maintain a list of air toxics, named as Hazardous Air Pollutants (HAPs), and to set emissions standards (National Emissions Standards for Hazardous Air Pollutants (NESHAPs) for many HAP emission sources; California incorporates HAP/NESHAP requirements into the state’s Toxic Air Contaminant (TAC) / Airborne Toxic Control Measure (ATCM) program. (I discussed these requirements HERE).