Pretreatment standards for existing sources (PSES).

Except as provided in 40 CFR 403.7 and 403.13, any existing source subject to this subpart which introduces pollutants into a publicly owned treatment works must comply with 40 CFR part 403 and achieve the following pretreatment standards for existing sources (PSES): Subpart AL—Ferric Chloride Pollutant or pollutant property PSES limitations Maximum for any 1 day Average of daily values for 30 consecutive days Milligrams per liter (mg/l) Total Chromium 3.0 1.0 Hexavalent Chromium 0.25 0.09 Copper (T) 1.0 0.50 Nickel (T) 2.0 1.0 Zinc (T) 5.0 2.5