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Industrial Pretreatment Program overview

Pollutants in industrial wastewater may compromise municipal treatment plant processes or contaminate waters of the state.  To protect municipal treatment plants and the environment, the Pretreatment Program requires industrial dischargers to use treatment techniques and management practices to reduce or eliminate the discharge of harmful pollutants to sanitary sewers.  The Pretreatment Program is a core part of the Clean Water Act's National Pollutant Discharge Elimination System (NPDES).

It has helped communities:

  • Maintain and restore watershed quality at a much lower cost than upgrading treatment;
  • Encourage pollution prevention;
  • Increase beneficial uses of sewage sludge;
  • Prevent formation of poisonous gases in the sanitary sewer system;
  • Meet wastewater discharge standards; and
  • Institute emergency-prevention measures.

The Purposes of Industrial Pretreatment Program (IPP)

  • Regulate the disposal of industrial wastewater into the sanitary wastewater collection system.
  • Protect the physical structures and the safety of operation and maintenance personnel of the wastewater system (collection and treatment).
  • Protect the health and safety of the public and the environment.
  • Comply with pretreatment regulations as required under the Federal General Pretreatment Regulations and Categorical Standards and local source control ordinances.

GENERAL PROHIBITIONS disallow industrial wastewaters introduced into Publicly Owned Treatment Works (POTWs) which:

  1. Pass through the POTWs untreated, and/or
  2. Interfere with the operation or performance of the POTWs,

SPECIFIC PROHIBITIONS disallow the introduction of eight specific categories of pollutants into POTWs as follows:

  1. Pollutants that create a fire or explosion hazard in the POTWs sewer system or at the treatment plant;
  2. Pollutants that are corrosive including any discharge with a pH lower than 5.0;
  3. Solid or viscous pollutants in amounts that would obstruct flow in the collection system and treatment plant, resulting in interference with operations;
  4. Any pollutant, including oxygen demanding pollutants released in a discharge at a flow rate and/or concentration which would cause interference;
  5. Heat in amounts which would inhibit biological activity in the POTW resulting in interference;
  6. Pollutants which result in the presence of toxic gases, vapors, or fumes in a quantity that may cause acute worker health and safety problems.
  7. Petroleum oil, nonbiodegradable cutting oil, or products of mineral oil origin in amounts that will cause pass through or interference.
  8. Trucked or hauled pollutants, except at discharge points designated by the Superintendent.