Significant Industrial Users

What is a Significant Industrial User?

  1. A user subject to categorical pretreatment standards;
  2. Or a user that

(a) Discharges an average of twenty-five thousand (25,000) gpd or more of process wastewater to the POTW (excluding sanitary, noncontact cooling, and boiler blowdown wastewater);

(b) Contributes a process wastestream which makes up five (5) percent or more of the average dry weather hydraulic or organic capacity of the POTW treatment plant; or

(c) Is designated as such by the Chester Sewer District and/or SCDHEC on the basis that it has a reasonable potential for adversely affecting the POTW’s operation or for violating any pretreatment standard or requirement.

(d) Is a categorical industrial discharger.



All industries permitted by the Chester Sewer District must perform self-monitoring and report quarterly results on analysis to the Chester Sewer District. As outlined by the rate study, results of analysis will be reported monthly due on or before the 14th day of the month for the preceding month. This will allow the Chester Sewer District to bill monthly for surcharges over 250 mg/L, BOD and TSS. We are presently charging a surcharge for all analysis over 300 mg/L BOD and TSS.

The District also performs compliance monitoring and inspection of each industry at least once annually. Pretreatment compliance monitoring will be conducted over seven (7) consecutive days of sampling for each CSD permitted industry. Any exceptions to this will be those industries who do not operate seven (7) days/week or 365 days/year. The minimum requirement by DHEC and EPA is to sample and inspect annually.

The industry is required to notify the Chester Sewer District of a violation of its permit within 24 hours of becoming aware of a violation. The user shall repeat sampling and analysis and submit the results of the repeated analysis to the Chester Sewer District within 30 days.