Following the adoption of polychlorinated biphenyl (PCB) and mercury (Hg) TMDLs for San Francisco Bay (SFBRWQCB, 2006, 2007), which mandate significant reductions in stormwater loads by 2028–2030, the Regional Water Board issued the first Municipal Regional Stormwater Permit (MRP) in 2009. The permit included provisions to improve information on PCB and Hg sources and loads and to identify and abate areas contaminated with these pollutants. To support these provisions, the Regional Monitoring Program for the San Francisco Bay (RMP) has conducted stormwater quality monitoring in smaller watersheds with a history of older industrial land use through a reconnaissance-style sampling program, in which a composite sample from a single storm is collected at each site. This report presents findings from Water Years (WYs) 2021 and 2022 and builds on previous efforts from WYs 2015–2020.