§ 91-4. Waste restrictions., Chapter 91. Sewers, Public, Ordinances, Code of Ordinances, Norwalk

No person shall discharge into any public sewer any waste, substance or waters other than such kinds or types of water-carried wastes for the conveyance of which the particular public sewer is intended, designed or provided.

No person shall discharge or cause to be discharged any stormwater, surface water, groundwater, roof runoff, subsurface drainage, uncontaminated cooling water or unpolluted industrial process waters to any sanitary sewer.

Stormwater and all other unpolluted drainage shall be discharged to such sewers as are specifically designated as storm sewers or to a natural outlet approved by the Director.

No person shall discharge or cause to be discharged any of the following described waters or wastes to any public sewers:

(1)

Any gasoline, benzene, naphtha, fuel oil or other flammable or explosive liquid, solid or gas.

(2)

Any waters or wastes containing toxic or poisonous solids, liquids or gases in sufficient quantity, either singly or by interaction with other wastes, to injure or interfere with any sewage treatment process, constitute a hazard to humans or animals, create a public nuisance or create any hazard in the receiving waters of the sewage treatment plant.

(3)

Any waters or wastes having a pH lower than 5.5 or having any other corrosive property capable of causing damage or hazard to structures, equipment and personnel of the sewage works.

(4)

Solid or viscous substances in quantities or of such size capable of causing obstruction to the flow in sewers or other interference with the proper operation 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 and paper dishes, cups, milk containers, etc., either whole or ground by garbage grinders.

No person shall discharge or cause to be discharged the following described substances, materials, waters or wastes if it appears likely, in the opinion of the Director, that such wastes 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 will 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 sewage treatment plant and other pertinent factors. The substances prohibited are:

(1)

Any liquid or vapor having a temperature higher than 150° F. or 65° C.

(2)

Any water or waste containing fats, wax, grease or oils, whether emulsified or not, in excess of 100 milligrams per liter or containing substances which may solidify or become viscous at temperatures between 32° and 150° F. or 0° and 65° C.

(3)

Any garbage that has not been properly shredded. The installation and operation of any garbage grinder equipped with a motor of 3/4 horsepower [0.76 horsepower metric] or greater shall be subject to the review and approval of the Director.

(4)

Any waters or wastes containing strong acid ironpickling wastes or concentrated plating solutions, whether neutralized or not.

(5)

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 sewage treatment works exceeds the limits established by the Director for such materials.

(6)

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

(7)

Any radioactive wastes or isotopes of such half-life or concentration as may exceed limits established by the Director in compliance with applicable state or federal regulations.

(8)

Any waters or wastes having a pH in excess of 9.5.

(9)

Materials which exert or cause:

(a)

Unusual concentrations of inert suspended solids, such as but not limited to fuller's earth, lime slurries and lime residues, or of dissolved solids, such as but not limited to sodium chloride and sodium sulfate.

(b)

Excessive discoloration, such as but not limited to dye wastes and vegetable tanning solutions.

(c)

Unusual BOD, chemical oxygen demand or chlorine requirements in such quantities as to constitute a significant load on the sewage treatment works, which may cause the effluent limitations of the discharge permit to be exceeded.

(d)

Unusual volume of flow or concentration of wastes constituting slugs as defined herein.

(10)

Waters or wastes containing substances that are not amenable to treatment only to such degree that the sewage treatment plant effluent cannot meet the requirements of other agencies having jurisdiction over discharge to the receiving waters.

Determination on discharge and review of facilities.

(1)

If any waters or wastes are discharged or are proposed to be discharged to the public sewers, which waters contain the substances or possess the characteristics enumerated in § 91-4, Waste restrictions, and which, in the judgment of the Director, may have a deleterious effect upon the sewage works, processes, equipment or receiving waters, the Director may:

(a)

Reject the wastes;

(b)

Require pretreatment to an acceptable condition for discharge to the public sewers;

(c)

Require control over the quantities and rates of discharge; and/or

(d)

Require additional payment to cover the added cost of handling and treating the wastes.

(2)

If the Director permits the pretreatment or equalization of waste flows, the design and installation of the plants and equipment shall be subject to the review and approval of the Director and subject to the requirements of all applicable codes, ordinances, laws and the municipal discharge permit. Further, such pretreatment installations must be consistent with the requirements of any state pretreatment permit issued to the industry.

Grease, oil and sand traps shall be provided when, in the opinion of the Director, they are necessary for the proper handling of liquid wastes containing grease in excessive amount or any flammable wastes, sand or other harmful ingredients, except that such traps shall not be required for private living quarters or dwelling units. All traps shall be of a type and capacity approved by the Director and shall be located as to be readily and easily accessible for cleaning and inspection.

Where preliminary treatment or flow-equalizing facilities are provided for any waters or wastes, they shall be maintained continuously in satisfactory and effective operation by the owner at his expense.

When required by the Director, the owner of any property serviced by a building sewer carrying industrial wastes shall install a suitable control manhole, together with such necessary meters, and other appurtenances in the building sewer to facilitate observation, sampling and measurement of the wastes. Such manhole, when required, shall be accessibly and safely located and shall be constructed in accordance with plans approved by the Director. The manhole shall be installed by the owner at his expense and shall be maintained by him so as to be safe and accessible at all times. All industries discharging into a public sewer shall perform such monitoring of their discharge as the Director and/or other duly authorized employees of the city may reasonably require, including installation, use and maintenance of monitoring equipment, keeping records and reporting the results of such monitoring to the Director. Such records shall be made available, upon request by the Director, to other agencies having jurisdiction over discharges to the receiving water.

All measurements, tests and analyses of the characteristics of waters and wastes to which reference is made in this chapter shall be determined in accordance with the latest edition of Standard Methods for the Examination of Water and Wastewater, published by the American Public Health Association, and shall be determined at the control manhole provided or upon suitable samples taken at said control manhole. In the event that no special manhole has been required, the control manhole shall be considered to be the nearest downstream manhole in the public sewer to the point at which the building sewer is connected. Sampling shall be carried out by customarily accepted methods to reflect the effect of constituents upon the sewage works and to determine the existence of hazards to life, limb and property.

No statement contained in this section shall be construed as preventing any special agreement or arrangement between the city and any industrial concern whereby an industrial waste of unusual strength or character may be accepted by the city for treatment, subject to payment therefor by the industrial concern, provided that such agreements do not contravene any requirements of existing federal laws and are compatible with any user charge and industrial cost-recovery system in effect.