TAC Imperial Riverside (part) Acetaldehyde 110 57 Benzene 463 239 "1,3-Butadiene" 55 36 Carbon tetrachloride 0 < .01 Chromium (Hexavalent) 0.0201 0.0187 para-Dichlorobenzene 7 15 Formaldehyde 327 164 Methylene Chloride 16 49 Perchloroethylene 80 79 Diesel PM 236 147