§ 21-203. Wastewater discharge prohibitions and limitations.

(a)

General prohibitions. No industrial user shall contribute or cause to be contributed, directly or indirectly, any pollutant or wastewater which causes pass through or interference. These general prohibitions and the specific prohibitions in paragraph (b) apply to all industrial users of the POTW whether or not the industrial users are subject to other pretreatment standards or requirements.

(b)

Specific prohibitions. No industrial user shall contribute the following pollutants into the POTW:

(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 wastewater facilities, including, but not limited to, wastestreams with a closed cup flashpoint of less than sixty (60) degrees Celsius or one hundred forty (140) degrees Fahrenheit using the test methods specified in 40 CFR Section 261.21. The director may require industrial users with the potential to discharge flammable, combustible or explosive substances to install and maintain an approved combustible gas detection meter or explosion hazard meter. No two (2) successive readings on an explosion hazard meter at the point of discharge shall be more than five (5) percent, nor any one (1) reading more than ten (10) percent, of the lower explosive limit (LEL) of the meter.

(2)

Solid or viscous substances which may cause obstruction to the flow in the POTW resulting in interference. This prohibition includes, but is not limited to, grease; garbage with particles greater than one-half (½) inch in any dimension; animal guts or tissues; paunch manure; bones; hair; hides or meshings; entrails; whole blood; feathers; ashes; cinders; sand; spent lime; stone or marble dust; metal; glass; straw; shavings; grass clippings; rags; spent grains; spent hops; wastepaper; wood; plastics; gas; tar, asphalt residues; residues from refining or processing of fuel or lubricating oil; waxes, mud; or glass grinding or polishing wastes, petroleum oil, non-biodegradable cutting oil, or produces of mineral oil origin.

(3)

Any wastewater having a pH less than 5.0 or higher than 12.5, or wastewater having any other corrosive property capable of causing damage or hazard to structures, equipment or personnel of the wastewater facilities.

(4)

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

(5)

Heat in amounts which will inhibit biological activity in the POTW resulting in interference, but in no case heat in such quantities that the temperature at the POTW treatment plant exceeds forty (40) degrees Celsius or one hundred four (104) degrees Fahrenheit unless the EPA, upon request of the POTW, approves alternate temperature limits;

(6)

Petroleum oil, non-biodegradable cutting oil, or products of mineral oil origin in amounts that will cause interference or pass through;

(7)

Pollutants which result in the presence of toxic gases, vapors, or fumes within the POTW in a quantity that may cause acute worker health and safety problems or pollutants which singly or cumulatively or by interaction with other wastes are sufficient to create a public nuisance or hazard to life or are sufficient to prevent or interfere with entry into the sewers for their maintenance and repair;

(8)

Any trucked or hauled pollutants, except at discharge points designated by the director;

(9)

Stormwater drainage from ground resulting in infiltration and inflow (I&I) through the industrial user's service line(s) or surface, roof drains, catch basins, unroofed area drains (e.g. commercial car washing facilities) or any other source unless otherwise approved by the director. Specifically prohibited is the connection of roof downspouts, exterior foundation drains, areaway drains, or other sources of surface runoff or ground water to a building sewer or building drain which in turn is connected directly or indirectly to the POTW. No industrial user shall connect or discharge water from underground drains, sump pump discharges, natural springs and seeps, water accumulated in excavation or grading or any other water associated with construction activities to the POTW.

(10)

Any substance which may cause the wastewater facilities' effluent, or any other product of the wastewater facilities, such as residues, sludges or scums, to be unsuitable for reclamation and reuse or to interfere with the reclamation process.

(11)

Any substance which will cause the city to violate its CDPS permit or the water quality standards for segment one (1) of the South Platte River or applicable groundwater standards.

(12)

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

(13)

A slug discharge as defined in section 21-202.

(14)

Any wastewater containing any radioactive wastes or isotopes of such half-life or concentration as may exceed limits established by the director or other regulations set forth by the State of Colorado or that violates any applicable state or federal regulations.

(15)

Bulk, expired, outdated or concentrated prescription or nonprescription drugs.

(16)

Wastewater or pollutants discharged directly into a manhole or other opening to the POTW unless specifically authorized by the director or as otherwise permitted under this article. Prohibited is the opening of a manhole or discharging into any opening in violation of this article.

(17)

No chemicals, materials, or substances, including but not limited to, paints, solvents, boiler or water treatment chemicals, sludges, chemicals, or wastes shall be stored in proximity to a floor drain or other sewer openings. Containers shall be clearly labeled and stored in a place where the chemicals, materials, substances or wastes, in case of leakage or rupture of the container, cannot enter the wastewater collection system. The storage of any chemicals, materials, substances or wastes that leak or have potential to leak or discharge into the wastewater collection system which may create an explosion hazard or in any way have a deleterious effect to the POTW or constitute a nuisance or a hazard to POTW personnel, the general public, the environment, or the receiving stream shall be prohibited.

(18)

Wastewater contaminated as a result of discharge from aboveground and/or underground gasoline, diesel fuels, fuel oil, kerosene, and jet fuel tanks, tank accessories, and/or pipelines without applying for and obtaining a permit prior to discharge.

(19)

Liquid wastes from chemical toilets, and trailers, campers or other recreational vehicles which have been collected and/or held in tanks or other containers shall not be discharged into the POTW except at locations authorized by the city to collect such wastes.

(20)

Sludges, screenings, or other residues from the pretreatment of industrial wastes.

(21)

Medical wastes that cause or contribute to pass through or interference.

(22)

Wastewater causing, alone or in conjunction with other sources, the POTW effluent to fail a toxicity test.

(23)

Detergents, surface-active agents, or other substances which may cause excessive foaming in the POTW or cause or contribute to pass through or interference.

(24)

Discharge of Nonylphenol from the use of bulk or concentrated Nonylphenol containing detergents as employed by some industrial or commercial laundries, car washes or asphalt manufacturers or other industrial users.

(25)

Wastewater which contains grease or oil or any other substances that will solidify or become discernibly viscous at temperatures between thirty-two (32) degrees Fahrenheit (0° Celsius) and one hundred fifty (150) degrees Fahrenheit (65.5° Celsius).

(26)

Wastewater containing free or floating oil and grease, or any discharge containing animal fat or grease by-product in excess of two hundred (200) milligrams per liter except where a food service establishment has installed and is properly operating and maintaining a grease interceptor and implementing all required BMPs.

(27)

Wastewater generated as a result of wastes pumped from grease interceptors, grease traps, sand-oil separators or other treatment units back into the POTW, either directly or indirectly, without approval of the director.

(28)

Discharge of any wastewater containing perchloroethylene (PCE) (also known as Tetrachloroethene and Tetrachloroethylene) from any industrial user involved in the dry cleaning business.

(c)

Specific discharge limitations.

(1)

No significant industrial user shall discharge or cause to be discharged wastewater that exceeds the following limits:

Pollutant(a)	Daily Maximum Discharge Limit (mg/L)
Arsenic	0.031
Cadmium	0.03
Chromium	4.08
Copper	0.38
Lead	0.17
Mercury	0.0011
Molybdenum	0.06
Nickel	0.50
Selenium	0.12
Silver	0.32
Zinc	2.17
BOD 5 , lbs/day(b)	10,119
TSS, lbs/day(b)	7,119
Bis(2-ethylhexyl) phthalate	0.27
Chloride(c)	466
Total dissolved solids (TDS)(d)	400

 

a.

All pollutants as total and in mg/L unless otherwise specified.

b.

These limits are the total mass in pounds per day (lbs/day) that are available to allocate to all permitted industrial users. Allocations are at the sole discretion of the city.

c.

If a significant industrial user (SIU) exceeds 466 mg/L Chloride, the SIU shall be required to sample and identify source(s) of Chloride in its wastestream.

d.

If a significant industrial user (SIU) exceeds 400 mg/L TDS, the SIU shall be required to sample and identify source(s) of TDS in its wastestream.

(2)

The city may, at its sole discretion, implement local limits through allocation of the maximum allowable industrial load (MAIL) to significant industrial users and correspond to the uniform concentration local limits shown in the table above. The MAILs that correspond to the daily maximum discharge limits are hereby incorporated by reference.

(3)

The following limits shall apply to wastewaters that are discharged from the groundwater cleanup of petroleum or gasoline underground storage tanks or other remediation wastewaters containing these pollutants or where these pollutants are appropriate surrogates. It shall be unlawful for any industrial user to discharge or cause to be discharged any waste or wastewater that exceeds the following limits, as applicable.

Pollutant(c)	Daily Maximum Limit (mg/L)
Benzene(a)	0.050
BTEX(b)	0.750

 

a.

All pollutants shown in the table are total.

b.

BTEX shall be measured as the sum of Benzene, Ethylbenzene, Toluene and Xylenes.

c.

These limits are based upon installation of air stripping technology as described in the EPA document: "Model NPDES Permit for Discharges Resulting from the Cleanup of Gasoline Released from Underground Storage Tanks, June 1989."

(d)

The director may establish more stringent pollutant limits, additional site-specific pollutant limits, best management practices, or additional pretreatment requirements when, in the judgment of the director, such limitations are necessary to implement the provisions of this article.

(e)

Dilution is prohibited as a substitute for treatment and shall be a violation of this article. Except where expressly authorized to do so by an applicable pretreatment standard or requirement, no industrial user shall ever increase the use of process water, or in any other way attempt to dilute a discharge as a partial or complete substitute for adequate treatment to achieve compliance with a pretreatment standard or requirement. The city may impose mass limitations on industrial users which are using dilution to meet applicable pretreatment standards or requirements or in other cases where the imposition of mass limitations is appropriate.

(f)

State requirements and limitations on discharges shall apply in any case where they are more stringent than federal pretreatment standards and requirements or those in this article.

(Ord. No. 10-2014, 10-14-14)