Notice is hereby given that pursuant to the federal regulations contained in 40 CFR 403.8.f(2)(vii), Central Contra Costa Sanitary District (Central San) is required to publish the names of all Industrial Users (IUs) of Central San’s public sewer system that were determined to be in Significant Non-Compliance (SNC) with applicable pretreatment standards or other pretreatment requirements during the 2022 calendar year. Federal regulations establish objective criteria for Central San to use to determine if an IU is in SNC.

DISCHARGE QUALITY VIOLATIONS

The following IU was found to have discharged process wastewater in violation of Central San’s Local Discharge Limits in a manner that met the definition of SNC.

Industrial User - Diablo Valley College, 321 Golf Club Road, Pleasant Hill, CA 94523

Nature of Violation - Limit violations for copper (3) in the discharge from the Life Science Building at concentrations that met the SNC criteria [Technical Review Criteria (TRC) and chronic].

Follow-up Action Taken - Central San issued Notices of Violation (NOVs) for the violations. The IU investigated potential sources of copper within the laboratory operations and did not locate any significant copper sources. The IU replaced the pretreatment unit serving the Life Science Building to improve the unit’s ability to remove regulated pollutants and flushed the waste lines from the laboratory areas to the pretreatment unit to remove potential legacy sources of copper. Limit violations occurred after these actions; therefore, Central San reinstated a suspended administrative civil penalty as agreed upon in the terms of a formal enforcement action taken in 2021. Subsequently, the IU conducted a cleaning of the pretreatment unit and conducted resampling. The resampling demonstrated that the IU returned to compliance.

Reporting Violations - No IUs were in SNC for reporting violations in 2022.