Upon the promulgation of the national categorical pretreatment standards for a particular industrial subcategory, the national standard, if more stringent than limitations imposed under this chapter for sources in that subcategory, shall immediately supersede the limitations imposed under this chapter. The Director or Chief Operator shall notify all affected users of the applicable reporting requirements under 40 CFR 403.12.
Where the City's wastewater treatment system achieves consistent removal of pollutants limited by national pretreatment standards, the City may apply to the approval authority for modification of specific limits in the national pretreatment standards. "Consistent removal" shall mean reduction in the amount of a pollutant or alteration of the nature of the pollutant by the wastewater treatment system to a less toxic or harmless state in the effluent which is achieved by the system in 95% of the samples taken when measured according to the procedures set forth in 40 CFR Part 403, General Pretreatment Regulations for Existing and New Sources of Pollution, promulgated pursuant to the Act. The City may then modify pollutant discharge limits in the national pretreatment standards if the requirements contained in 40 CFR 403.7 are fulfilled and prior approval from the approval authority is obtained.
A. 
No user shall discharge wastewater to the sanitary sewer system when any of the pollutant concentrations exceed the limits specified in the following. These concentrations shall be applied to wastewater effluents at a point just prior to discharge into the City sewer system. With the express written consent of the Director of the Department of Public Works or the Chief Operator of the POTW, users with multiple discharge outfalls may combine waste streams by calculation to report on wastewater characteristics.
Table 1
Substance
Concentration Limit
(mg/L)
Arsenic
0.10
Cadmium
0.20
Cyanide-complex
0.80
Chromium, hexavalent
0.10
Chromium-total
1.00
Copper
1.00
Iron
10.0
Lead
0.10
Mercury
0.001
Nickel
2.00
Selenium
0.05
Silver
0.10
Zinc
0.60
Phenolic compounds
5.00
Oil and grease
100.00
Sulfide
3.00
B. 
The Director of the Department of Public Works may impose mass limitations in addition to the concentration-based limitations above. The Director may also develop and impose limitations on additional parameters on a case-by-case basis.
C. 
All users are prohibited from discharging those materials listed in § 277-37 in excess of the applicable limits set forth herein.
A. 
No person shall discharge or permit the discharge or infiltration into the City sewer system of wastes containing the following pollutants in excess of the listed concentrations unless prior approval is granted by the Director or Chief Operator of the POTW:
(1) 
Wastes containing more than 200 mg/l of five-day biochemical oxygen demand (BOD).
(2) 
Wastes containing more than 200 mg/l of total suspended solids (TSS).
(3) 
Wastes containing more than 100 mg/l of total organic carbon (TOC).
(4) 
Wastes containing more than 400 mg/l of chemical oxygen demand (COD).
(5) 
Wastewater in volumes constituting greater than 25,000 gallons/day.
B. 
Allowable increases of the pollutant concentrations in Subsection A(1) through (4), as well as volume in Subsection A(5), may be subject to a surcharge due to extra-strength wastes, as set forth in § 277-61 of this chapter.
State requirements and limitations on discharges shall apply in any case where they are more stringent than national requirements and limitations or those in this chapter.
No user shall ever increase the use of process water or in any way attempt to dilute a discharge as a partial or complete substitute for adequate treatment to achieve compliance with the limitations contained in the national categorical pretreatment standards, or in any other pollutant-specific limitation developed by the City or state.