This study evaluates the effectiveness of various stormwater control measures (SCMs) in removing polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), both in dissolved forms and associated with different-sized solids. The SCMs evaluated include biofilters, a hybrid biofilter + media filter, a retention pond, and treatment trains with hydrodynamic separators and cartridge filters. The targeted particle size fractions were clay (0.7-2.7 µm), fine silt (2.7-20 µm), coarse silt (20-63 µm), and sand (>
63 µm), along with their associated PAHs and PCBs. Samples were collected from multiple storm events at the inlets and outlets of these SCMs on current and former military bases in the Southwestern and Northwestern US. The study found that coarse particles (>
20 µm) contained significantly higher fractions of organic carbon (f