Mass-discharge-based limitations.

A. The Chief Plant Operator and/or Superintendent of Sewers may impose mass-discharge-based limits on individual users for specific pollutants based upon a wastewater treatability analysis. Mass-discharge-based limits may be imposed for pollutants which may have negative impact on the POTW, POTW employees or the receiving water. The Chief Plant Operator and/or Superintendent of Sewers shall issue permits to significant industrial users and may issue permits to other industrial/commercial users limiting the discharge of these substances. Each permit shall restrict the discharge from each significant industrial user to a portion of the total allowable influent loading.

In determining what portion of the total of each substance that each significant industrial user shall be allowed to discharge, the Chief Plant Operator and/or Superintendent of Sewers shall consider:(1) The quantities of each substance that are uncontrollable because they occur naturally in wastewater;(2) The quantities of each substance that are anthropogenic but are nonetheless uncontrollable;(3) Historical discharge trends;(4) Past pollution control efforts of each user as compared to other dischargers of the same substance;(5) Potential for growth in the POTW service area;(6) Potential for more restrictive regulatory requirements to be placed on the POTW discharge or sludge disposal or sludge reuse method; and(7) Treatability of the substance.

The Chief Plant Operator and/or Superintendent of Sewers shall apply a 15% safety factor protective of the POTW.B. Permits issued in accordance with this section may allow for discharges in excess of limitations set forth under § 257-73.