Pretreatment

DEQ’s pretreatment program regulates pollutants from industrial and commercial facilities that discharge directly into publicly and privately-owned treatment works (POTWs). The objectives for the pretreatment program are as follows:

• Prevent the introduction of pollutants into a POTW that will interfere with its operation, including interference with the use or disposal of sewage sludge.
• Prevent the introduction of pollutants into a POTW that will pass through the treatment works or otherwise be incompatible with the works.
• Improve the opportunities to recycle and reclaim wastewater and sewage sludge.

Approved City Program

DEQ relies on a publicly and privately-owned treatment works (POTW) to regulate industrial dischargers to its sewer system to protect the health and safety of staff and the integrity of the treatment process. A POTW with a total design flow greater than 5 MGD receiving discharges from industrial users (IUs) that could cause pass through interference or are otherwise subject to pretreatment standards, may need to develop a pretreatment program. DEQ may also require a POTW with a design flow of less than 5 MGD to develop a pretreatment program if the POTW receives significant wastewater contributions from industrial sources that warrant a pretreatment program. DEQ is the approval authority responsible for the following:

• Reviewing and approving a POTW’s pretreatment program application.
• Designating the POTW as the control authority authorized to control its discharges.
• Ensuring that the POTW complies with pretreatment conditions in its IPDES permit and with the appropriate provisions of 40 CFR 403.

DEQ Program

DEQ ensures that a significant industrial user (SIU) discharging to a publicly and privately-owned treatment works (POTW) without an approved pretreatment program complies with the National Pretreatment Standards (40 CFR 403.6). DEQ acts as the control authority for POTWs that need an approved program. In some cases, DEQ will assist in the development of the necessary program elements to ensure timely approval and implementation of a compliant program. In other cases, DEQ may permanently act as the control authority for a POTW’s SIUs and will work directly with the POTW to develop local limits and issue control mechanisms.

Dental Amalgam Program

EPA promulgated pretreatment standards to reduce discharges of mercury and other metals from dental offices into POTWs by requiring amalgam separators for facilities regularly placing and removing amalgam. All dental facilities must submit a one-time compliance report certifying:

• Whether they discharge amalgam
• If a separator is installed
• If the facility is in compliance with best management practices for cleaning vacuum lines, water lines, and chair-side traps.