Significant Industrial Users: Federal Categorical

pharmaceutical comapany


Significant Industrial Users (SIUs) are classified as either Federal Categorical or Non-Categorical. Federal Categorical Industrial Users are also known as Categorical Industrial Users (CIUs).

A Significant Industrial User is defined as:

  • Any industrial user conducting processes subject to EPA Federal Categorical Pretreatment regulation
  • Any industrial user that discharges an average of 25,000 or more gallons per day
  • Any industrial user designated by the City to adversely impact the sewer system

If the preliminary information indicates that the industrial user is a potential SIU, a joint audit by Inspection and Engineering staff will be conducted. During the joint audit of the facility, inspectors gather the basic information, while the permitting engineers examine in detail the industrial unit processes, sources and volume of wastewater, pretreatment system, etc., required to create the Fact Sheet.

Certain industries fall into the categories regulated by the National Categorical Standards as defined by the Federal Codes of Regulation. The EPA has developed regulations for over twenty industrial categories. Examples of facilities classified as CIUs include:

  • Electroplating shops
  • Steam electric power plants
  • Pharmaceutical facilities

In addition to the federal discharge limitation, CIUs are subject to the City's local limits. As a CIU you are required to obtain a permit. You can download the CIU permit here.