On July 12, 2017, Yolo-Solano AQMD (YSAQMD) adopted Rule 3.25 for Federal New Source Review at major PM2.5 sources. This rule incorporates the federal nonattainment New Source Review (NSR) requirements from the Clean Air Act for PM2.5 in the areas of Yolo-Solano County which are designated as nonattainment for PM2.5. These NSR rules require pre-construction permits for new major sources of PM2.5 and major modifications at existing major sources of PM2.5. Additional details about this new rule may be found in staff report for this new rulemaking here or at the District's website.