Industrial Pretreatment

Industrial Pretreatment Program

The City of Cedar Hill and Trinity River Authority administers local, state, and federal regulations affecting area businesses and the quality of the waster discharged to the City's sanitary sewer system. The City of Cedar Hill sends domestic and commercial wastewater to the Trinity River Authority for treatment before being released into the Trinity River.

Wastewater Permits

In the City of Cedar Hill, the control authority for the Industrial Pretreatment Program is the Trinity River Authority. Certain industries with potential to discharge into the sanitary sewer system may need to apply for a City of Cedar Hill wastewater permit. For more information, please refer to the Code of Ordinances Chapter 18 Article IV.

General Industrial Users (IU)

General Industrial Users (IU) include any industrial or commercial facility that discharges wastewater into the City's sanitary sewer system. IUs are not subject to the federal categorical pretreatment regulations, do not fit the definition of a significant industrial user, and do not require a permit to discharge wastewater to the sanitary sewer system. The City has the right to permit, inspect, and monitor any IU at anytime. All IUs must comply with all applicable environmental regulations.

Significant Industrial Users (SIU)

Significant Industrial Users (SIU) are sources of industrial wastewater that require an increased level of regulatory attention by federal regulation. SIUs shall obtain a wastewater permit to discharge any industrial wastewater to the City's sanitary sewer system. SIUs are defined as an industrial user that meets any one of the following criteria:

  • Is subject to Categorical Pretreatment Standards under 40 CFR 403.6 and 40 CFR Chapter I Subchapter N.
  • Discharges an average of 25,000 gallons per day or more of process wastewater to the City's sanitary sewer system.
  • Contributes a process waste stream that makes up 5 percent or more of the average dry weather hydraulic or organic capacity of the wastewater treatment plant.
  • Is designated as such on the basis that the industrial user has a reasonable potential for adversely affecting the operation of the treatment plant or the City's collection system, or for violating any pretreatment standards or requirements.

Categorical Industrial User (CIU)

Categorical Industrial Users (CIU) are sources of industrial wastewater that have specific categorical standards set by federal regulation. CIUs shall obtain a wastewater permit to discharge any industrial wastewater to the City's sanitary sewer system. CIUs are defined as an industrial user that meets these conditions:

  • The industrial activity performed at the facility is regulated by one or more of the federal regulations found in 40 CFR parts 400 through 699.
  • The facility discharges process wastewater to the City's sanitary sewer system.
  • IN the EPA Pretreatment Categories and Standards, the categorical activity is assigned pretreatment limitations, reporting requirements, or both.

TMAH PROHIBITION GUIDANCE