§ 16.22.060. Prohibited discharges.

No person shall contribute or cause to be contributed, directly or indirectly, any pollutant or wastewater which will interfere with the operation or performance of the sewage collection and treatment facilities. These general prohibitions apply to all such users of the municipal sewer system whether or not the user is subject to national categorical pretreatment standards or any other national, state or local pretreatment standards or requirements. A user shall not contribute the following substances:

(1)

Any liquids, solids or gases which by reason of their nature or quantity are, or may be sufficient either alone or by interaction with other substances, to cause fire or explosion or be injurious in any other way to the municipal sewer system or to the operation of the sewage treatment plant, or which reasonably appear to present an imminent endangerment to the health or welfare of POTW workers and general public. At no time shall two successive readings on an explosion hazard meter, at the point of discharge into the system (or at any point in the system), be more than five percent nor any single reading over ten percent of the lower explosive limit (LEL) of the meter. Prohibited materials include, but are not limited to, gasoline, fuel oil, hexane, kerosene, naphtha, benzene, toluene, xylene, ethers, alcohols, ketones, aldehydes, peroxides, chlorates, perchlorates, bromates, carbides, hydrides, and sulfides;

(2)

Any solids, natural or man-made fibers, insoluble or emulsified oils, fats, or greases, slurries or viscous materials of such character or in such quantity that may cause an obstruction to the flow in the sewer or otherwise interfere with the proper functioning of the sewage works such as, but not limited to, ashes, cinders, sand, mud, straw, shavings, metal, glass, rags, feathers, tar, plastics, wood, unground garbage, whole blood, paunch manure, hair and fleshings, entrails, paper dishes, cups, milk containers, bones, spent lime, stone and marble dust, grass clippings, rags, spent grains, spent hops, asphalt residues, residues from refining or processing of fuel or lubricating oils, and polishing wastes;

(3)

Any waters, wastes, material or substances which are corrosive or irritating to human beings and/or animals, toxic or noxious, or which contain toxic or poisonous solids, liquids, or gases in sufficient quantity, either singly or by interaction with other wastes, to injure or interfere with the sewage treatment process, constitute a hazard to humans or animals, create a public nuisance, or create any hazard in the receiving waters of treated effluent or the sewage treatment plants;

(4)

Substances, material, waters, or wastes, listed below, if it appears likely in the opinion of the director that such matter can harm either the sewers, sewage treatment process, or equipment, have an adverse effect on the receiving stream, or can otherwise endanger life, limb, public property, or constitute a nuisance. In forming his opinion as to the acceptability of these wastes, the director shall give consideration to such factors as the quantities of subject wastes in relation to flows and velocities in the sewers, materials of construction of the sewers, nature of the sewage treatment process, capacity of the sewage treatment plant, degree of treatability of wastes in the POTW, and other pertinent factors which reasonably appear to present an imminent endangerment to the health or welfare of POTW workers and general public;

(5)

The substances prohibited are:

(a)

Any wastewater having a temperature which shall inhibit biological activity in the treatment plant resulting in interference, but in no case wastewater from an indirect discharge with a temperature exceeding one hundred fifty degrees Fahrenheit (sixty-five degrees Centigrade), or which exceeds one hundred four degrees Fahrenheit (forty degrees Centigrade) at the POTW treatment plant,

(b)

Any water or wastes which contain fats, wax, grease or oils, whether emulsified or not, or containing substances which may solidify, or become viscous, at temperatures between thirty-two degrees Fahrenheit and one hundred fifty degrees Fahrenheit (zero degrees to sixty-five degrees Centigrade), in quantities determined by the director that have a deleterious effect upon the POTW conveyance system, processes, and/or equipment, or in quantities which will pass through the POTW to the receiving waters, or impact the storage or disposal of the POTW biosolids. In addition, it is prohibited to discharge these substances in quantities that cause a sewer line blockage resulting in untreated sewage discharging to waters of the United States. The discharge must not be in quantities that present an imminent endangerment to the health and welfare of persons, or otherwise create or constitute a public nuisance. Wastewater contaminated with oils which include, but are not limited to, petroleum oil, nonbiodegradable cutting oil, or products of mineral oil origin, shall not exceed concentrations of one hundred mg/L of oil and grease,

(c)

Any waters or wastes containing strong acid, iron pickling wastes, or concentrated plating solutions, whether neutralized or not,

(d)

Any waters or wastes containing iron, chromium, copper, zinc and similar objectionable or toxic substances; or wastes exerting an excessive chlorine requirement, to such degree that any such material received in the composite sewage at the treatment works exceeds the limits established by the director for such materials, as shown in the table of limits, subsection (13) of this section,

(e)

Any waters or wastes containing phenols or other taste or odor-producing substances, in such concentrations exceeding limits established by the director, after treatment of the composite sewage, as necessary to meet the requirements of local, state, federal or other public agencies of jurisdiction for such discharge to the receiving waters,

(f)

Any waters or waste containing dissolved sulfide in excess of one mg/L at the point of discharge into the municipal sewer system;

(6)

Any wastewater containing any radioactive wastes or isotopes of such half-life or concentration as may exceed limits established by the director in compliance with applicable local, state, or federal regulations;

(7)

Any wastewater having a pH less than 5.5 or in excess of 12.0 or wastewater having any other corrosive property capable of causing damage or hazard to structures, equipment and/or personnel of the POTW,

(8)

Any pollutants, including oxygen-demanding pollutants, (BOD, TSS, etc.) released at a flow rate and/or pollutant concentration which will cause interference with the POTW;

(9)

Any wastewater with objectionable color not removed in the treatment process, such as, but not limited to, dye wastes and vegetable tanning solutions;

(10)

Any wastewater of unusual volume of flow or concentration of wastes constituting "slugs";

(11)

Pollutants which will cause a fire or explosion hazard in the POTW including, but not limited to, wastestreams with a closed cup flashpoint of less than one hundred forty degrees Fahrenheit (sixty degrees Centigrade) using the test methods specified in 40 CFR 261.21, or amendments thereof;

(12)

Waters and wastes containing substances which are not amenable to treatment or reduction by the sewage treatment processes employed, or are amenable to treatment only to such degree that the sewage treatment plant effluent cannot meet the requirements of agencies having jurisdiction over discharge to the receiving waters, or any substance which may cause the sewage treatment plant effluent or any other product of the municipal sewer system such as residues, sludges or scums to be unsuitable for reclamation and reuse or to interfere with the reclamation process. In no case shall a substance discharged to the municipal sewer system cause the sewage treatment plant to be in noncompliance with sludge use or disposal criteria, guidelines, or regulations developed under Section 405 of the Act; any criteria, guidelines or regulations affecting sludge use or disposal developed pursuant to the Solid Waste Disposal Act, the Clean Air Act, the Toxic Substances Control Act or state criteria applicable to the sludge management method being used;

(13)

Any wastes contributed by users of the POTW which either singly or in conjunction with other significant industrial users cause the POTW influent to exceed the following limits:

Parameter Daily Maximum (lbs/day)
Cyanide, total	7:23
Copper	56.21
Nickel	36.50
Chromium	84.72
Silver	24.26
Zinc	162.70
Lead	1.65
Cadmium	3.95
Mercury	.310
Arsenic	5.316
Molybdenum	5.39
Phenol compounds	80.5

 

Any waste exceeding the following limits:

ParameterDaily Maximum (mg/L)
Sulfide	1.0

 

(14)

The amounts of the listed pollutants calculated in pounds shall be allocated to each industrial user based on the industrial user's average daily discharge flow volume contributed to the municipal sewer system. The average shall be based upon the industrial user's daily discharge flow. It shall be calculated twice per year using the first six months average daily flow for the second half, and the last six months of the year for the following year. Concentration limits in milligrams per liter (mg/L) shall be applied to each industrial user based on the following discharge flow categories.

Industrial User
Daily Discharge Flow
Category
(gals/day)

1	0—10,000
2	10,001—20,000
3	20,001—30,000
4	30,001—60,000
5	60,001—100,000
6	100,001—200,000
7	200,001—500,000
8	Greater than 500,000

 

At least annually, the director shall determine which category applies to each industrial user and distribute the amounts of pollutants, calculated in pounds, applying a concentration limit in the industrial users wastewater discharge permit. If an industrial user significantly changes the amount of wastewater discharged to the sanitary sewer, causing the user to change categories, the user must notify the director at least thirty days prior to implementing the change;

(15)

Any wastes which exhibit toxicity characteristics based on the bioassay test that causes a fifty percent reduction of the luminescent microorganisms light output (EC50). When using the Microtox bioassy test, the wastewater must not exhibit an EC50 toxicity value of less than 1.9 within the five minute test period, in two consecutive tests taken in a forty-eight hour period;

(16)

All industrial and commercial facilities using silver in manufacturing or as a part of a process operation, including but not limited to, the development and/or printing of photographic pictures or x-rays, precious metal plating, or any operation where silver is reasonably expected to be found in the facilities' wastewater, shall not discharge silver bearing wastewater to the POTW without first treating the wastewater to remove the silver or subjecting the wastewater to a silver recovery process, or disposing the silver bearing wastewater at an approved disposal location; These facilities shall follow the guidelines listed in the City of Wichita Code of Management Practices for Silver and Mercury Dischargers.

(17)

Any substances, materials, water or wastes which will cause interference with or pass through the POTW;

(18)

Substances, materials, water or wastes which are hazardous as defined by 40 CFR: Part 261.21 (ignitable), Part 261.22 (corrosive), Part 261.23 (reactive), Part 261.24 (EP toxic), Part 261.31 (hazardous waste from nonspecific source), and Part 261.32 (hazardous waste from specific source);

(19)

Any trucked or hauled wastewater, except at discharge points designated by the POTW. All waste haulers shall conform to the regulations set forth in Chapter 7.08 of this Code;

(20)

All industrial and commercial facilities using mercury in manufacturing, or as a part of a process operation, including but not limited to, the replacing and restoring dental amalgam fillings, using mercury compounds in laboratory reagents, or using mercury bearing measuring devices such as thermometers and sphygmomanometers, or any operation where mercury is reasonably expected to be found in the facilities' wastewater, shall not discharge mercury bearing wastewater to the POTW without first treating the wastewater to remove the mercury, or disposing the mercury-bearing wastewater at an approved disposal location; These facilities shall follow the guidelines listed in the City of Wichita Code of Management Practices for Silver and Mercury Dischargers;

(21)

Any wastes containing Aqueous Fire Fighting Foam in the amount that results in foam in the collection system or the treatment process in quantities that result in POTW interference and or pass through and inhibits the nitrification process at the POTW.

(Ord. 43-772 §§ 2, 4 (part); Ord. No. 46-888, § 2, 2-14-06)