§ 68-172 PROHIBITED DISCHARGES.
   The following discharges to the public sewer system shall be prohibited.
      (1)   Any liquid or vapor having a temperature higher than 150 degrees Fahrenheit or of a temperature which causes the influent to the treatment plant to exceed 104 degrees Fahrenheit, whichever is lower.
      (2)   Any gasoline, benzene, naphtha, fuel oil, petroleum oil, non-biodegradable cutting oil products or mineral oil in amounts that would cause interference or pass through, or other flammable or explosive liquid, solid or gas.
      (3)   Any garbage that has not been properly shredded.
      (4)   Any ashes, cinders, sand, mud, straw, shavings, metal, glass, rags, feathers, tar, plastics, woods, paunch manure or any other solid or viscous substance capable of causing obstruction to flow in sewers or other interference with the proper operation of the sewage works.
      (5)   Discharges greater than the following concentrations of specific pollutants:
Daily Maximum (24 hour composite) - unless otherwise specified below
Daily Maximum (24 hour composite) - unless otherwise specified below
BOD (biochemical oxygen demand
1600 mg/l
Total suspended solids
2200 mg/l
Total phosphorus
30 mg/l
Fats, total (grab)
250 mg/l*
Fats, non-polar (grab)
50 mg/l
Phosphorus
30 mg/l
Ammonia-N
22 mg/l
pH (grab)
Lower than 6.0 or higher than 9.0*
 
Inorganics
Inorganics
Aluminum
2.1 mg/l
Arsenic
0.26 mg/l
Beryllium
0.01 mg/l
Cadmium
0.032 mg/l
Chromium
1.2 mg/l
Copper
0.9 mg/l
Available cyanide1 (grab)
0.03 mg/l*
Lead
0.16 mg/l
Total mercury3
Non-detect
Molybdenum
0.18 mg/l
Nickel
0.25 mg/l
Selenium
0.09 mg/l
Silver
0.014 mg/l
Zinc
1.4 mg/l
 
Notes:
1   Nondetectible per U.S. EPA method 245.
2   Nondetectible per U.S. EPA method 608.
3   Nondetectible per U.S. EPA method 245.1 at a detection level of 0.2 :g/l.
*   Based on daily mean calculated from a minimum of 4 appropriately spaced grab samples in lieu of 24-hour composite.
   A user shall comply with all categorical pretreatment standards and any other pretreatment requirements established under §§ 307(b), 307(c), or 402(b)(8) of the Act (33 U.S.C. 1347) that are applicable to that user. If a categorical pretreatment standard and another limit contained in this article regulate any same pollutant, then the more restrictive of the two shall apply.
   Future conditions imposed on the city by government agencies with proper jurisdiction may require subsequent amendment of this subsection by the city. Where federal or state promulgated pretreatment standards require limits on parameters not covered in this subsection or limits more stringent than those specified in this subsection, the state or federal limits shall have precedence and take effect with respect to the applicable user on the later of: (i) their promulgation date, or (ii) the date specified for compliance with such standards.
      (6)   Any waters or wastes containing suspended solids of such character and quantity that unusual attention or expense is required to handle such materials at the sewage treatment plant.
      (7)   Any pollutants to the POTW that result in toxic gases, vapors, and fumes in quantities that might cause worker health and safety problems, or any malodorous gas or liquid substances capable of creating a public nuisance.
      (8)   No industrial waste that may cause a deviation from the NPDES permit requirements, pretreatment standards and all other state and federal regulations.
      (9)   Any waters or wastes having a pH lower than 6.0 or higher than 9.0 or having any other corrosive properties capable of causing damage or hazard to structures, equipment and personnel of the wastewater system.
      (10)   Any wastewater containing any radioactive wastes or isotopes of such halflife or concentration as may exceed limits established by the city in compliance with the applicable state or federal regulations.
      (11)   Any discharge to the sewer which will result in a nuisance or contamination or pollution of receiving waters.
      (12)   Any discharge which would violate any statue, rule, EPA regulation or ordinance of any public agency.
      (13)   Any pollutants with a closed cup flash point of less than 140 degrees Fahrenheit.
      (14)   Any trucked or hauled wastes to POTWs, except at discharge points designated by the POTW. Any truck waste which is targeted for discharge into the POTW system must receive written permission from the city prior to discharge. A report must be prepared indicating what type of waste is going to be discharged and in what condition the pollutant will be.
(1993 Code, § 68-172) (Ord. passed 1-22-2001; Ord. 2014-01, passed 1-27-2014)