Pretreatment standards for existing sources

Pretreatment standards for existing sources. Pretreatment standards for existing sources. Except as provided in ss. NR 211.13 and 211.14 , any existing source subject to this subchapter which introduces pollutants into a POTW shall comply with ch. NR 211 and the TTO concentration in the discharge may not exceed 1.37 milligrams per liter for any one day.