TAC San Luis Obispo Santa Barbara Ventura Acetaldehyde 106 112 171 Benzene 308 383 633 "1,3-Butadiene" 59 56 97 Carbon tetrachloride 0 0.07 0.05 Chromium (Hexavalent) 0.0031 0.0288 0.019 para-Dichlorobenzene 12 19 35 Formaldehyde 281 337 471 Methylene Chloride 43 127 173 Perchloroethylene 40 77 116 Diesel PM 270 302 498