§ 13-702. Prohibitions and limitations of wastewater discharges.

(1)

General prohibitions. No user may introduce into POTW any pollutant(s) which cause pass through or interference.

(2)

Deleterious wastes enumerated. No deleterious industrial wastes shall be discharged to the city's wastewater system. An industrial waste shall be considered deleterious to the wastewater system if it may cause any of the following effects:

(a)

Violations of pretreatment standards as adopted by the city.

(b)

Violations by the treatment plant of its discharge permit or applicable receiving water standards, applicable air pollution permits, or solid waste permits.

(c)

Chemical reaction either directly or indirectly with the material of construction of the wastewater system in such a manner as to impair the strength or durability of the sewer structure.

(d)

Mechanical action that will destroy the sewer structure.

(e)

Restriction of the hydraulic capacity of the sewer structure.

(f)

Restriction of the normal inspection or maintenance of the sewer structure.

(g)

Danger to public health and safety.

(h)

Obnoxious conditions inimical to public interest.

(3)

Prohibited discharges. No persons shall discharge or cause or allow to be discharged or deposited into the city's wastewater system any wastewater that contains the following:

(a)

Petroleum-based oils and greases.

(i)

Oil grease, nonbiodegradable cutting oil, or products of mineral oil origin in amounts that will cause interference or pass through.

(ii)

Wastewater from industrial facilities containing floatable fats, wax, grease, or oils.

(b)

Explosive mixtures. Liquids, solids, or gases that 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 system or its operation. At no time shall two (2) successive readings on an explosion hazard meter at the point of discharge into the city's wastewater system be more than five (5) percent nor any single reading over ten (10) percent of the lower explosive limit (LEL) of the meter or have a closed cup flash point less than one hundred forty (140) degrees Fahrenheit or sixty (60) degrees Celsius. Prohibited materials include, but are not limited to, gasoline, kerosene, naphtha, benzene, toluene, xylene, ethers, alcohols, ketones, aldehydes, peroxides, chlorates, perchlorates, bromides, carbides, hydrides, and sulfides.

(c)

Noxious material. Noxious or malodorous solids, liquids, or gases that either singly or by interaction with other wastes are capable of creating a public nuisance or hazard to life or that are or may be of sufficient concentration to prevent entry into a sewer for its maintenance and repair. 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.

(d)

Improperly shredded garbage. Garbage that has not been ground or comminuted to such a degree that all particles will be carried freely in suspension under flow conditions normally prevailing in the public sewers, with no particle greater than one-half-inch in any dimension.

(e)

Radioactive wastes. Radioactive wastes or isotopes of such half-life or concentration that they do not comply with regulations or orders issued by the appropriate authority having control over their use or that may cause damage or hazards to the wastewater system or operating personnel.

(f)

Solid or viscous wastes. Solid or viscous wastes that will or may cause obstruction to the flow in the POTW resulting in interference. Prohibited materials include, but are not limited to, greases, uncomminuted garbage, paunch manure, ashes, cinders, sand, spent lime, stone or marble dust, metal, glass, straw, shavings, grass clippings, rags, spent grains, spent hops, waste paper, wood, plastic, tar, asphalt residues, residues from refining or processing of fuel or lubricating oil, and similar substances, or other substances with a specific gravity in excess of two and sixty-five hundredths (2.65). Bones, hair, hides or fleshings, entrails, whole blood, and feathers, from slaughterhouses are also prohibited.

(g)

Excessive discharge rate. Wastewaters at a flow rate or containing such concentrations or quantities of pollutants that exceed for any time period longer than fifteen (15) minutes more than five (5) times the average twenty-four-hour concentration, quantities, or flow during normal operation that would cause interference with the POTW.

(h)

Toxic substances. Any toxic substances that would cause the concentration of the wastewater at the influent structure of the treatment facility to exceed the limits in table 1. The city shall monitor the treatment works influent for each parameter in the following tables. Each industrial user shall be responsible for monitoring and reporting these requirements. In the event that the influent at the treatment works reaches or exceeds the levels established by the table, the city shall initiate technical studies to determine the cause of the influent violation and shall recommend to the city such remedial measures as are necessary, including, but not limited to, recommending the establishment of new or revised pretreatment levels for these parameters. The city shall also recommend changes to any of these criteria in the event the publicly owned treatment works' effluent standards are changed, that there are changes in any applicable law or regulation affecting them, or in the event changes are needed for more effective operation of the publicly owned treatment works. The intent of these limitations is to prevent:

(i)

Interference with the operation of the treatment works;

(ii)

Pass through of pollutants in violation of the publicly owned treatment works' NPDES permit limitations; and

(iii)

Municipal sludge contamination.

Table I. Protection Criteria
Incompatible Pollutant Influent Limitations for the Clarksville Wastewater Treatment Plant

Pollutant	Maximum Daily Average Concentration (mg/l)
Arsenic	0.10
Cadmium	0.01
Chromium (total)	0.34
Copper	1.0
Cyanide	0.05
1, 2 and 1, 4 dichlorobenzene	1.6
Iron	10.0
Lead	0.1
Mercury	0.007
Nickel	0.26
Silver	0.94
Tetrachloroethylene	0.1
Toluene	1.0
Zinc	0.29

 

Table II. Protection Criteria
Compatible Pollutant Influent Limitations for the Clarksville Wastewater Treatment Plant

Pollutant	Maximum Daily Average Concentration (mg/l)	Maximum Instantaneous Concentration (mg/l)
5-day BOD	245	270
TSS	238	270

 

Modification of federal categorical pretreatment standards. Where the city's wastewater treatment system achieves consistent removal of pollutants limited by federal pretreatment standards, the city may apply to the approval authority for modification of specific limits in the federal pretreatment standards. "Consistent removal" (as defined hereinafter) 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 that is achieved by the system when ninety-five (95) percent of the samples taken measured according to the procedures set forth in Section 403.7(c)(2) of Title 40 of the Code of Federal Regulations, 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 federal pretreatment standards if the requirements contained in 40 CFR, part 403, section 403.7 are fulfilled and prior approval from the approval authority is obtained.

(i)

Unpolluted waters and extraneous flow. Any unpolluted water of extraneous flow, including, but not limited to, water from cooling systems or of stormwater origin that will increase the hydraulic load on the wastewater treatment system.

(j)

Discolored material. Wastes with objectionable color or that cause excessive discoloration (such as, but not limited to, dye wastes, vegetables, and tanning solutions).

(k)

Corrosive wastes. Any waste that will cause corrosion or deterioration of the wastewater system. All wastes discharged to the city's wastewater system must have a pH value in the range of six (6) to nine (9) standard units. Prohibited materials include, but are not limited to, acids, bases, sulfides, concentrated chloride and fluoride compounds, and substances that react with water to form acid or basic products.

(l)

Thermal pollution. Any wastewater that has a temperature equal to or greater than one hundred fifty (150) degrees Fahrenheit or equal to or less than thirty-two (32) degrees Fahrenheit that will cause the temperature of the receiving wastewater at the plant to exceed one hundred four (104) degrees Fahrenheit or heat in amounts which will inhibit biological activity in the POTW resulting in interference.

(m)

Trucked or hauled pollutants. Any trucked or hauled pollutants, except at discharge points designated and approved by the city.

(4)

Limitations on wastewater discharges. The normal upper limits on compatible pollutants are three hundred (300) mg/l for biochemical oxygen demand, three hundred twenty-five (325) mg/l for suspended solids, and one hundred (100) mg/l for oils and greases. Customers discharging wastewater containing compatible pollutants within the range of concentrations listed below may be allowed to discharge and be charged a surcharge in accordance with section 13-706:

(a)

Biochemical oxygen demand (BOD) within three hundred (300) mg/l to one thousand (1,000) mg/l.

(b)

Suspended solids within three hundred twenty-five (325) mg/l to eight hundred (800) mg/l.

(c)

Animal and/or vegetable oils and greases within one hundred (100) mg/l to three hundred (300) mg/l.

Customers discharging wastewater containing compatible pollutants greater than the upper limit concentrations listed in this section may be issued a violation of their wastewater permit in addition to the surcharge.

(5)

Septic tank and other disposal system discharges. No person, firm, association, or corporation shall clean out, drain, or flush any septic tank or any other type of wastewater or excreted disposal system into the publicly owned treatment works unless the person, firm, association, or corporation obtains a permit from the city to perform such acts or service. Any person, firm, association, or corporation desiring a permit to perform such services shall complete and file with the city an application on the form prescribed by the city. Upon any such application, the city shall issue the permit when the conditions of this section have been met, providing the city is satisfied the applicant has adequate and proper equipment to perform the services contemplated in a safe and competent manner. The waste hauler permit shall be conditional upon payment of annual user charges and dumping charges as established by the gas, water, and sewer committee. The city shall designate approved locations for the emptying and cleansing of all equipment used on the performance of the services rendered under the permit herein provided for, and it shall be a violation hereof for any person, firm, association, or corporation to empty or clean such equipment at any place other than a place so designated. No person, firm, association, or corporation rendering services under the permit herein provided for shall discharge any incompatible pollutant.

(6)

Dilution prohibited as substitute for treatment. Except where expressly authorized 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.

(7)

The industrial user shall notify the POTW, the EPA Regional Waste Management Division Director, and state hazardous waste authorities in writing of any discharge into the POTW of a substance, which, if otherwise disposed of, would be a hazardous waste under Tennessee Code 1200-1-11.

(a)

Such notification must include the name of the hazardous waste as set forth in 1200-1-11, the EPA hazardous waste number, and the type of discharge (continuous, batch, or other). The notification shall also contain the following information to the extent such information is known and readily available to the industrial user: An identification of the hazardous constituents contained in the waste stream discharged during that calendar month, and an estimation of the mass of constituents in the waste stream expected to be discharged during the following twelve (12) months.

(b)

In the case of an notification made under this paragraph, the industrial user shall certify that it has a program in place to reduce the volume and toxicity of hazardous wastes generated to the degree it has determined to be economically practical.

( Ord. No. 41-2016-17 , § 1, 1-5-17)