Discharge Limits

Discharge Limits & Levels

Found in Fox Metro Ordinance #864

The following is a general listing of various categories of wastewater discharge limits and levels found in Fox Metro Water Reclamation District Industrial Wastewater Pretreatment Ordinance #864 (Ordinance #864). It is a general listing only. For more detailed information the reader should stop by the Fox Metro Business Services and Laboratory Building, located at 682 State Route 31, Oswego, IL. or contact Fox Metro at (630)892-4378 and request a copy of Ordinance #864. A cost-recovery charge may apply to such requests.

Fox Metro enforces a variety of wastewater discharge limits and levels, some having distinct numerical limits; others being narrative standards; some being locally derived; others being required by state or federal regulations. The following sections reference the section of Ordinance #864 where the limits or levels can be found; and contain a brief description of their nature.

Local Limits

(Ordinance #864, Section 300.120)

The following are numerical local discharge limits derived by Fox Metro using USEPA provided procedures.

Unless otherwise indicated, concentrations in this section are expressed in mg/L and refer to the total amount of the constituent present in all phases, whether solid, suspended or dissolved, elemental or combined, including all oxidation states. Where constituents may be measured as other than total, the word “total” is indicated for clarity.

The Hexane Extractable Material, indicated in this section and Section 300.125 of Ordinance #864, refers to the sum of polar hydrocarbons (such as vegetable oils, animal fats, and other highly biodegradable oils) and non-polar hydrocarbons (such as petroleum based oils and greases) as determined by HEM and SGT-HEM analyses. The Silica Gel Treated Hexane Extractable Material in this section refers to petroleum oil, non-biodegradable cutting oil, products of mineral oil origin and other non-polar hydrocarbons as determined by HEM and SGT-HEM analyses.

Discharges from each separate discharge of a User, as measured under the provisions of this Ordinance shall not contain in excess of the following concentrations based upon a 24-hour composite sample.

PollutantMaximum Concentration
Ammonia Nitrogen500 mg/L
Arsenic, Total0.145 mg/L
Biochemical Oxygen Demand (CBOD5)5,500 mg/L
Cadmium, Total0.04 mg/L
Chromium, Total6.4 mg/L
Copper, Total1.0 mg/L
Iron, Total100 mg/L
Lead, Total0.4 mg/L
Manganese, Total4.9 mg/L
Mercury, Total0.0005 mg/L
Molybdenum, Total1.0 mg/L
Nickel, Total0.400 mg/L
Selenium, Total0.095 mg/L
Silver, Total0.7 mg/L
Total Suspended Solids (TSS)10,500 mg/L
Zinc, Total2.4 mg/L

Discharges exceeding the numeric standard for Total Mercury shall be allowed if all of the following conditions are met:

  • The discharger does not use mercury; or, the discharger uses mercury and this use cannot be eliminated; or, the discharger uses mercury only in chemical analysis or in laboratory or other equipment and takes reasonable care to avoid contamination of wastewater; and,
  • The discharger is providing the best degree of treatment consistent with technological feasibility, economic reasonableness and sound engineering judgment. This may include no treatment for mercury; and,
  • The discharger has an inspection and maintenance program likely to reduce or prevent an increase in the level of mercury discharges.

However, in no case shall any discharge of mercury, alone or in combination with other sources, cause pass through or interference at the POTW as prohibited by 40-CFR-403.5(a)(1).

  • Discharges exceeding the numeric standard for Total Silver shall be allowed if all of the following conditions are met:
  • The discharger does not use silver; or, the discharger uses silver and this use cannot be eliminated; or, the discharger uses silver only in chemical analysis or in laboratory or other equipment and takes reasonable care to avoid contamination of wastewater; and,
  • The discharger is providing the best degree of treatment consistent with technological feasibility, economic reasonableness and sound engineering judgment as indicated in the most current version of the “Code of Management Practice for Silver Dischargers”, as published by the Association of Metropolitan Sewerage Agencies (AMSA) and the Silver Council; and,
  • The discharger has an inspection and maintenance program likely to reduce or prevent an increase in the level of silver discharges.

However, in no case shall any discharge of silver, alone or in combination with other sources, cause pass through or interference at the POTW as prohibited by 40-CFR-403.5(a)(1).

Discharges from each separate discharge of a User, as measured under the provisions of the Ordinance, shall not contain in excess of the following concentrations based upon a grab sample.

PollutantMaximum Concentration
Cyanide, Total0.136 mg/L
Hexane Extractable Materials (HEM)1,000 mg/L
Silica Gel Treated Hexane Extractable Materials (SGT-HEM)100 mg/L
Phenol, Total10.7 mg/L

Prohibitive Discharge Standards

(Ordinance #864, Section 300.105)

The following are narrative standards, most of which are required by federal regulation, but many of which would have been required by Fox Metro anyway.

No User shall contribute or cause to be contributed, directly or indirectly, any pollutant or wastewater which will interfere with the operation or performance of the Fox Metro wastewater treatment system or will pass through the wastewater treatment system.

In addition, the following pollutants shall not be introduced into the Fox Metro wastewater treatment system:

(1) Pollutants which create a fire or explosion hazard in the wastewater collection system, including, but not limited to:

(i) waste streams with a closed cup flashpoint of less than 140 degrees Fahrenheit or 60 degrees Centigrade using the test methods specified in 40-CFR-261.21; or

(ii) at no time shall two (2) successive Lower Explosion Limit (LEL) readings of five percent (5%) nor any single reading of ten percent (10%) occur at any point in the wastewater treatment system.

(2) Any wastewater which will cause corrosive structural damage to the wastewater treatment system, but in no case wastewater having a pH less than 5.0 units, or any wastewater having a pH greater than 12.5 units which is not in accordance with the notification requirements of Section 300.165 of this Ordinance.

(3) Solid or viscous substances which may cause obstruction to the flow in a sewer or other interference with the operation of the wastewater treatment facilities such as, but not limited to, grease, garbage with particles greater than one-half inch (1/2″) in any dimension, animal guts, or tissues, paunch manure, bones, hair, hides or fleshings, entrails, whole blood, feathers, ashes, cinders, sand, spent lime, stone or marble dust, metal, glass, straw, shavings, grass clippings, rags, spent grains, spent hops, waste paper, wood, plastics, tar, asphalt residues from refining or processing of fuel or lubrication oil, mud, glass, grinding or polishing wastes, tumbling or deburring stones, or any material which can be disposed of as trash.

(4) Any wastewater containing pollutants, released at a flow or concentration, either singly or by interaction with other sources, to injure or cause interference with any wastewater treatment process, constitute a hazard to humans or animals, cause pass through resulting in a violation of the water quality standards of the receiving waters of the Fox Metro wastewater treatment system, exceed any limitation set forth in a National Categorical Pretreatment Standard (when effective) or in Section 300.120 of this Ordinance or create a public nuisance.

(5) Any wastewater having a temperature which will inhibit biological activity in the wastewater treatment plant resulting in Interference; in no case shall wastewater be discharged which causes temperatures at the head of the Fox Metro wastewater treatment plant to exceed 104 degrees Fahrenheit or 40 degrees Centigrade.

(6) Petroleum oil, non-biodegradable cutting oil, or products of mineral oil origin in amounts that will cause Interference or Pass Through.

(7) Any pollutant(s), which either singly or by interaction with other wastewater, result in the presence of toxic gases, vapors or fumes in the Fox Metro wastewater treatment system in a quantity that may cause acute worker health and safety problems to occur.

(8) Trucked or hauled pollutants, except at discharge points designated by Fox Metro in accordance with Section 300.180 of this Ordinance.

(9) Any noxious or malodorous liquids, gases, or solids which either singly or by interaction with other wastewaters are sufficient to create a public nuisance or hazard to life or are sufficient to prevent entry into sewers for their maintenance and repair.

(10) In no case shall a substance be discharged into the Fox Metro wastewater collection system which causes Fox Metro 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 RCRA, SWDA, the Clean Air Act, or State criteria applicable to the sludge management method being used.

(11) Any wastewater containing any radioactive wastes or isotopes of such half-life or concentration as may exceed limits established by the latest State or Federal Regulations including Section 10-CFR-20 and Illinois Administrative Code Title 32: Chapter II: Subchapter b: Part 340. (Amended per Ordinance 659, November 20, 2002.)

The limit as established at the time Ordinance 659 was passed per 10-CFR-20, Appendix B is given by the following equation:

where:
CRA-226 = the concentration of Radium 226 in picocuries per liter.
CRA-228 = the concentration of Radium 228 in picocuries per liter.

(12) Any wastewater containing compatible pollutants of such character and quantity that unusual attention or expense is required to handle such materials at the sewage treatment plant; provided, however, that a User may be permitted by specific written agreement with Fox Metro, which agreement to discharge such compatible pollutants may provide for special charges, payments or provisions for treating or testing equipment.

(13) Any discharge exceeding the standards established in 35-Ill. Adm. Code 307.

(14) Any slug discharged into the Fox Metro wastewater treatment system.

(15) Any regulated medical waste as defined by 40-CFR-259.30(a), or residues resultant from treatment and destruction processes of said waste, except as specifically authorized by the District Manager in a Discharge Permit.

(16) Any wastewater containing detergents, surface active agents, or other substances which may cause excessive foaming in the Fox Metro wastewater treatment system.

Excessive Strength Discharge Surcharges

(Ordinance #864, Section 300.125)

Fox Metro has determined that certain pollutants are compatible with the wastewater treatment process. Fox Metro reserves the right to recover the treatment costs for those compatible pollutants that exceed the surcharge levels listed in this section.

Compatible PollutantSurcharge Level
Biochemical Oxygen Demand (CBOD5)200 mg/L
Total Suspended Solids (TSS)250 mg/L
Ammonia Nitrogen (NH3-N)25 mg/L
Hexane Extractable Materials (HEM)100 mg/L

The excessive strength sewage surcharges for these pollutants are calculated using the following formula:

Ps = ( Pavg – Psl ) x Q x 8.345 x TCp

where:

  • Ps = the excessive strength surcharge for the given compatible pollutant.
  • Pavg = the average concentration of the compatible pollutant for the wastewater discharge in question.
  • Psl = the surcharge level concentration of the compatible pollutant as indicated in any Fox Metro Ordinances or Rate Schedules in effect at the time the surcharge is calculated.
  • Q = the Industrial User wastewater flow in millions of gallons (MG).
  • 8.345 = a factor which converts the product of concentration (mg/L) and flow (MG) into pounds of compatible pollutant.
  • TCp = the treatment cost charge per pound of the compatible pollutant, such charge being stipulated by any Fox Metro Ordinances or Rate Schedules in effect at the time the surcharge is calculated.

State Requirements

(Ordinance #864, Section 300.115)

Fox Metro is required to enforce State of Illinois Pretreatment Program requirements. Ordinance 864 incorporates these by reference. The reader should consult Title 35 of the Illinois Administrative Code, Parts 307 and 310 to see which of these regulations may apply under a given set of circumstances.

Federal Categorical Pretreatment Standards

(Ordinance #864, Section 300.110)

Fox Metro is required to enforce federal National Pretreatment Program requirements. Ordinance 864 incorporates these by reference. The reader should consult Title 40 of the Code of Federal Regulations, Parts 403 through 471 to see which of these regulations may apply under a given set of circumstances.

List of Industries Having Federally Promulgated Categorical Standards:

40-CFR Part#Industrial Category
405Dairies
406Grain Mills
407Canned & Preserved Fruits & Vegetables Processing
408Canned & Preserved Seafood Processing
409Sugar Processing
410Textile Mills
411Cement Manufacturing
412Feedlots
413Electroplating
414Organic Chemicals, Plastics & Synthetic Fibers
415Inorganic Chemicals Manufacturing
417Soap & Detergent Manufacturing
418Fertilizer Manufacturing
419Petroleum Refining
420Iron & Steel Manufacturing
421Nonferrous Metals Manufacturing
422Phosphate Manufacturing
423Steam Electric Power Generating
424Ferroalloy Manufacturing
425Leather Tanning & Finishing
426Glass Manufacturing
427Asbestos Manufacturing
428Rubber Manufacturing
429Timber Products Processing
430Pulp, Paper & Paperboard
431The Builders’ Paper & Board Mills
432Metal Products
433Metal Finishing
434Coal Mining
435Oil & Gas Extraction
436Mineral Mining & Processing
439Pharmaceutical Manufacturing
440Ore Mining & Dressing
443Paving & Roofing Materials (guidelines)
446Paint Formulating
447Ink Formulating
455Pesticide Chemicals
457Explosives Manufacturing
458Carbon Black Manufacturing
459Photographic
460Hospitals
461Battery Manufacturing
463Plastics Molding & Forming
464Metal Molding & Casting
465Coil Coating
466Porcelain Enameling
467Aluminum Forming
468Copper Forming
469Electrical & Electronic Components
471Nonferrous Metals Forming & Metal Powders

Aurora, North Aurora, Boulder Hill, Montgomery, Oswego, Sugar Grove and portions of Yorkville and Batavia

National Association of Clean Water Agencies National Association of Clean Water Agencies - Awards

© 2024 Fox Metro Water Reclamation District - Contact Us - Public Notices - Careers - FOIA - Accessibility