Code of Federal Regulations Title 40. Protection of Environment § 40.403.2 Objectives of general pretreatment regulations

(a) To prevent the introduction of pollutants into POTWs which will interfere with the operation of a POTW, including interference with its use or disposal of municipal sludge;

(b) To prevent the introduction of pollutants into POTWs which will pass through the treatment works or otherwise be incompatible with such works;  and

(c) To improve opportunities to recycle and reclaim municipal and industrial wastewaters and sludges.