Developed by the Office of Environmental Health Hazard Assessment (OEHHA) at the request of CalEPA, CalEnviroScreen is a science-based tool that identifies the California communities most burdened by pollution from multiple sources and most vulnerable to its effects. The tool will be used to help implement a state law (SB 535) that requires that 25 percent of the proceeds from the state’s cap-and-trade auctions be invested in projects that benefit disadvantaged communities, including 10 percent for projects located within these areas.