§ 55.017  LOCAL LIMITS.
   (A)   The following pollutant limitations are established to protect against pass through interference and biosolids quality. No person shall discharge wastewater containing in excess of the following daily maximum concentrations based upon grab.
Daily Maximum Concentration Limitations
Daily Maximum Concentration Limitations
Arsenic (total)
.064 mg/l
Cadmium (total)
.04 mg/l
Copper
1.23 mg/l
Cyanide (total)
.27 mg/l
Hex. Chromium
.3 mg/l
Lead (total)
.31 mg/l
Molybdenum (total)
.10 mg/l
Nickel
.70 mg/l
Oil & grease [1]
100 mg/l
Selenium
.14mg/l
Silver
2mg/l
Total Chromium
1.0 mg/l
Zinc (total)
2.5mg/l
[1]   As an alternative to the total oil and grease limitations established by this section, the Board of Public Works may establish in an IWP a limitation of 50 mg/l for non-polar grease. The alternative limitation is subject to the following conditions:
      1.   The user submits an application for the alternative limit;
      2.   The user provides information regarding the user’s products, processes, and operations that shows to the Board of Public Works’ satisfaction that the oil and grease discharged by the user is predominantly of animal or vegetable origin;
      3.   The user shows that the oil and grease in the user’s discharges is not visible, free, or floating at 50°F at any time;
      4.   The user has sampling facilities that allow for both, visual inspection of the user’s discharge and using the equipment necessary for collection samples for floatable oil and grease;
      5.   The oil and grease in the user’s discharge is not related to past instances of obstruction, interference, or pass through;
      6.   Users subject to the alternative limit shall continue to operate and maintain grease traps and any other oil and grease separation and treatment equipment and shall continue all existing practices that reduce discharges of oil and grease;
      7.   If the Board of Public Works determines that a user subject to the alternative limit has caused, alone or in conjunction with other discharges, obstruction, interference, or pass through, then the user shall comply with the total oil and grease limitation or another appropriate limitation established by the Board in the user’s IWP; and
      8.   Any other appropriate conditions set forth in the user’s SIU.
 
   (B)   The above limits apply at the point where the wastewater is discharged to the POTW. All concentrations for metallic substances are for “total” metal unless indicated otherwise. The Wastewater Superintendent may impose mass limitations in addition to, or in place of, the concentration-based limitations above.
   (C)   Upon the promulgation of the national categorical pretreatment standard (NCPS) for a particular user, the said standard, if more stringent then the limitations imposed under this chapter for sources in that category, shall, when effective, immediately supersede the limitations and conditions imposed under this chapter. The Wastewater Superintendent shall notify all known affected users of the applicable permitting and reporting requirements under 40 C.F.R. § 403.12.
(Ord. 2010-2, passed 4-20-2010)