Williams Municipal Code Art. 5 Industrial Wastewater Requirements

A. To provide for fair and equitable use of sewage system, the city shall have the unqualified right to require an industrial user to provide information necessary to ensure compliance with all laws, rules, regulations and provisions of this chapter.

B. All information and data on an industrial user shall be available to the public and governmental agencies in accordance with the Public Records Act, unless the industrial user specifically requests and is able to demonstrate to the satisfaction of the city that the release of such information would divulge information, processes or methods which would be detrimental to the user's competitive position. The demonstration of the need for confidentiality made by the permittee shall meet the burden necessary for holding such information from the general public under applicable state and federal law.

In any event, the city shall not limit US EPA's access to any information provided by the discharger.

In any event, effluent data, as defined by 40 CFR 2.302 will not be deemed confidential. Such information may include, but is not limited to:

1. Wastewater discharge peak flow rates and volume over a specified time period.

2. Physical, chemical, bacteriological, or radiological analysis of wastewaters.

3. Information on raw materials, processes, and products.

4. Quantity and disposition of specific liquid, sludge, oil, solvent, or other materials.

5. Details of wastewater pretreatment facilities, their operation and maintenance.

6. Details of systems to prevent and control the losses of materials through spills to the sewage system.

7. Detailed plumbing plans indicating all sources discharging to the on or off-site pretreatment or sewage system.

8. A slug control program, per 40 CFR 403.8(f)(2)(v).

9. Notification of discharges of a listed hazardous waste as defined RCRA to the sewage system per 40 CFR 403.12(p).

10. Baseline monitoring reports per 40 CFR 403.12(b).

11. Compliance progress reports in accordance with all provisions listed in 40 CFR 403.12(c)(d)(e).

12. Notification of potential problems, including slug loading in accordance with all provisions listed in 40 CFR 403.12(f).

13. Notification of substantial changes in volume or character of pollutants discharged in accordance with all provisions listed in 40 CFR 403.12(j).

14. Monitoring and analysis reports demonstrating continued compliance in accordance with all provisions listed in 40 CFR 403.12(g).

(Ord. No. 270-25, § 1(Exh. A), 5-21-2025)

A. Pollutants, substances, or wastewater prohibited by this section shall not be processed or stored in such a manner that they could be discharged to the city's collection system.

B. No user shall introduce or cause to be introduced into the city's collection system the following pollutants, substances, or wastewater:

1. Pollutants which create a fire or explosive hazard in the WWTP or collection system, including, but not limited to, waste streams with a closed-cup flashpoint of less than one hundred forty degrees Fahrenheit (sixty degrees Celcius) using the test methods specified in 40 CFR 261.21;

2. Wastewater having a pH less than six or more than nine, or otherwise causing corrosive structural damage to the WWTP or collection system or equipment;

3. Solid or viscous substances in amounts which will cause obstruction of the flow in the WWTP or collection system resulting in interference but in no case solids greater than three-eighths inches in any dimension;

4. Pollutants, including oxygen-demanding pollutants (BOD, etc.), released in a discharge at a flow rate and/or pollutant concentration which, either singly or by interaction with other pollutants, will cause interference with the WWTP or collection system;

5. Any liquid, water or wastewater having a temperature greater than one hundred fifty degrees Fahrenheit (sixty-five degrees Celcius), or which will inhibit biological activity in the WWTP resulting in interference, but in no case wastewater which causes the temperature at the introduction into the WWTP to exceed one hundred fifty degrees Fahrenheit (sixty-five degrees Celcius);

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

7. Any water or waste containing floatable grease, oil, fat or other ether-soluble matter in excess of fifty parts per million, or dispersed nonfloatable grease, oil, fat or ether-soluble matter other than soap, in excess of five hundred parts per million;

8. Any garbage, except garbage shredded to one-quarter-inch maximum size from individual dwelling units. In no event will industrial, commercial or institutional sewer systems qualify for the exception;

9. Any ashes, bones, hair, whole blood, cinders, and mud, straw, shavings, metal, glass, rags, feathers, tar, plastics, wood, paunch manure, or any other solids or viscous substances capable of causing obstruction to the flow in sewers or other interference with the proper operation of the wastewater works;

10. Pollutants which result in the presence of toxic gases, vapors, or fumes within the WWTP or collection system in a quantity that may cause acute worker health and safety problems;

11. Trucked or hauled pollutants, except at discharge points designated by the public works director;

12. Noxious or malodorous liquids, gases, solids, or other wastewater which, either singly or by interaction with other wastes, are sufficient to create a public nuisance or a hazard to life, or to prevent entry into the sewers for maintenance or repair;

13. Wastewater which imparts color which cannot be removed by the treatment process, such as, but not limited to, dye wastes and vegetable tanning solutions, which consequently imparts color to the WWTP's effluent;

14. Wastewater containing any radioactive material or isotopes except in compliance with applicable state or federal regulations;

15. Storm water, surface water, groundwater, artesian well water, roof runoff, subsurface drainage, swimming pool drainage, condensate, deionized water, noncontact cooling water, and unpolluted wastewater, unless specifically authorized by the public works director;

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

17. Detergents, surface-active agents, or other substances which may cause excessive foaming in the WWTP or collection system;

18. Wastewater required to be manifested under RCRA, unless specifically authorized by the public works director;

19. Infectious wastes as defined in the California Health and Safety Code;

20. Any waters or wastes containing a hazardous substances, hazardous material, or a toxic pollutant in sufficient quantity to injure or interfere with any wastewater treatment process, constitute a hazard to humans, or animals, or create any hazard in the receiving water of the plant;

21. Any waters or wastes containing suspended solids or dissolved matter of such character and quantity that unusual attention or exposure is required to handle such materials at the plant;

22. Any waters or wastes containing more than one-tenth milligrams per liter of dissolved sulfides;

23. Any radioactive material in an amount greater than recommended by local or state public health agencies;

24. Any water added for the purpose of diluting wastes which would otherwise exceed applicable maximum concentration limitations;

25. Any septic tank sludge, except at an authorized location with a valid disposal permit;

26. Any waters or wastes having a median toxicity limit (TLm) lower than twenty-five percent as determined by a ninety-six-hour bioassay;

27. Any waters or wastes containing algicides, fungicides, antibiotics, insecticides, strong oxidizing agents, or strong reducing agents;

28. Any noxious or malodorous gas or substances capable of creating a public nuisance either by itself or by interaction with other substances;

29. Any wastes requiring an excessive quantity of chlorine or other chemical compound used for disinfection purposes;

30. Any waste producing excessive discoloration of wastewater or treatment plant effluent;

31. Any garbage, cheese, fruit, vegetable, fish, animal, or other solid material from any food processing plant, or retail grocery store, unless the discharge has been shredded to one-quarter-inch maximum size and does not contain more than five percent soil material by weight (dry basis);

32. Any garbage, or any fruit, vegetable, animal, fish, or other solid industrial wastes resulting from the processing, packaging or canning of fruits, vegetables, fish, or other foods or products, or other industrial operation, unless such wastes have first been passed through screens having openings not exceeding one thirty-second of an inch in dimension. As part of the industrial wastewater discharge permit, the public works director may authorize the discharge of such wastes if they are first passed through screens having larger openings if the public works director is satisfied that such larger openings will provide screening efficiency and effectiveness equal to or better than that provided by openings of one thirty-second of an inch in dimension;

33. Any waters or wastes containing recognizable portions of the human anatomy;

34. Any unusual volume of flow or concentration of waste, from a commercial or industrial source, of any constituent, or in quantity of flow that exceeds for any period of duration longer than fifteen minutes, that is five times the average twenty-four-hour concentration or flow during normal operation;

35. Any waters or wastes containing substances which are not amenable to treatment or which cause the WWTP effluent to fail to meet waste discharge requirements established by the State Water Resources Control Board, the California Regional Water Quality Board, or other state or regulatory agency;

36. Any water or wastes containing any of the following substances exceeding the concentrations listed in Table 1;

Table 1 — Maximum Allowable Concentrations

(Ord. No. 270-25, § 1(Exh. A), 5-21-2025)

A. All pretreatment systems or devices required by this chapter or any permit issued under this chapter shall be approved by the city engineer and shall meet the standards of this section, but such approval shall not absolve the discharger of the responsibility of meeting any effluent limitation required by the city. All pretreatment systems judged by the city engineer to require engineering design shall have plans prepared and signed by an engineer of suitable discipline licensed in the State of California.

B. Normally, a gravity separation interceptor, equalizing tank, neutralization chamber and control manhole will be required, respectively, to remove prohibited settleable and floatable solids, to equalize wastewater streams varying greatly in quantity and/or quality, to neutralize low or high pH flow and to facilitate inspection, flow measurement and sampling.

C. Floor drains from commercial or manufacturing buildings, warehouses or multi-use structures shall not discharge directly to the sewer, but shall first discharge to a gravity separation interceptor.

D. Grease, oil, and sand interceptors shall be provided by the waste discharger when, in the opinion of the city engineer, they are necessary for the proper handling of liquid wastes containing grease in excessive amounts, or any flammable wastes, sand, or other harmful ingredients. All interceptors shall be of a type and capacity approved by the city engineer, and shall be so located as to be readily and easily accessible for cleaning and inspection.

E. For buildings which require a pretreatment system or device, all domestic or domestic wastewater from restrooms, showers, drinking fountains, kitchen area, etc., shall be kept separate from all industrial wastewater until the industrial wastewater have passed through any required pretreatment system or device. A control manhole of a design approved by the city engineer shall be furnished and installed by certain designated industrial wastewater dischargers to facilitate inspection, sampling and flow measurements by personnel of the city. This control manhole shall be located off the industrial premise or if within plant fence, a special locked gate provided, with keys to the gate lock given to the city. Unrestricted access to this control manhole shall be available to authorized personnel of the city at all times. The control manhole may be used as a junction manhole for domestic wastewater and industrial wastes provided the junction occurs downstream of the sampling or flow measuring point.

(Ord. No. 270-25, § 1(Exh. A), 5-21-2025)

A. The categorical pretreatment standards found at 40 CFR 401—471 are hereby incorporated.

B. Where a categorical pretreatment standard is expressed only in terms of either the mass or the concentration of a pollutant in wastewater, the public works director may impose equivalent concentration or mass limits in accordance with 40 CFR 403.6(c).

C. When wastewater subject to a categorical pretreatment standard is mixed with wastewater not regulated by the same standard, the public works director shall impose an alternate limit using the combined waste stream formula in 40 CFR 403.6(e).

D. A user may obtain a variance from a categorical pretreatment standard if the user can prove, pursuant to the procedural and substantive provisions in 40 CFR 403.13, that factors relating to its discharge are fundamentally different from the factors considered by US EPA when developing the categorical pretreatment standard.

E. A user may obtain a net gross adjustment to a categorical standard in accordance with 40 CFR 403.15.

(Ord. No. 270-25, § 1(Exh. A), 5-21-2025)

A. No user shall discharge or cause to be introduced directly or indirectly into the city's collection system, a quantity or quality of wastewater which exceeds the local limits on discharges to public sewer mains established by the city.

B. These limits apply at the point where the wastewater is discharged to the city's collection system. The public works director may impose limitations based on concentrations of pollutants in milligrams per liter or as an amount of pollutants in pounds per day.

(Ord. No. 270-25, § 1(Exh. A), 5-21-2025)

No person shall own, lease, install, replace, enlarge, or operate any regenerating ion-exchange water conditioning and/or softening equipment or similar devices for softening all or part of a water supply to a property which has a connection to the public sewer system, storm water system, or which drains onto the land.

(Ord. No. 270-25, § 1(Exh. A), 5-21-2025)

A. The city reserves the right to establish, by ordinance or in wastewater discharge permits, more stringent standards or requirements on discharges to the WWTP or collection system.

(Ord. No. 270-25, § 1(Exh. A), 5-21-2025)

A. No user shall ever increase the use of process water or, in any way, attempt to dilute a discharge as a partial or complete substitute for adequate treatment to achieve compliance with a discharge limitation unless expressly authorized by an applicable pretreatment standard or requirement. The public works director may impose such limitations on the amount, in pounds per day, of pollutants discharged by users who are using dilution to meet applicable pretreatment standards or requirements, or in other cases when the imposition of such limitations is appropriate.

(Ord. No. 270-25, § 1(Exh. A), 5-21-2025)

A. Cesspool, septic tank and holding tank pumping's containing only domestic and/or sanitary wastes will be accepted only at city designated locations from holders of both a valid liquid waste hauler water discharge permit issued by the city and a valid environmental health permit issued by the County of Colusa. The contents of any cesspool or septic tank may not be pumped directly into a public sewer main unless specifically approved by the city under emergency or other abnormal short duration circumstances. Wastes from industrial process sources are prohibited and may not be hauled and discharged to the public sewer system.

B. No waste hauler discharging septic waste or sanitary waste shall discharge constituents in excess of the limits specified in the respective industrial waste discharge permit.

(Ord. No. 270-25, § 1(Exh. A), 5-21-2025)