A. 
General prohibitions. No user shall introduce or cause to be introduced into the POTW any pollutant or wastewater which causes pass-through or interference. These general prohibitions apply to all users of the POTW whether or not they are subject to categorical pretreatment standards or any other national, state or local pretreatment standards or requirements.
B. 
Specific prohibitions. No user shall introduce or cause to be introduced into the POTW the following pollutants, substances or wastewater:
(1) 
Pollutants which create a fire or explosive hazard in the POTW, including but not limited to waste streams with a closed-cup flash point of less than 140° F. (60° C.) using the test methods specified in 40 CFR 261.21.
(2) 
Wastewater having a pH less than 5.0 or more than 10.0 or otherwise causing corrosive structural damage to the POTW or equipment or personnel of the POTW.
(3) 
Solid or viscous substances in amounts which will cause obstruction of the flow in the POTW resulting in interference.
(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 POTW.
(5) 
Wastewater having a temperature greater than 150° F. (65° C.) or which will inhibit biological activity in the treatment plant resulting in interference, but in no case wastewater which causes the temperature at the introduction into the treatment plant to exceed 104° F. (40° C.).
(6) 
Petroleum oil, nonbiodegradable 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.
(8) 
Noxious or malodorous liquids, gases, solids or other wastewater which, either singly or by interaction with other wastes, is sufficient to create a public nuisance or a hazard to life or to prevent entry into the sewers for maintenance or repair.
(9) 
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 treatment plant's effluent, thereby violating the City of Aberdeen's NPDES permit.
(10) 
Wastewater containing any radioactive wastes or isotopes except in compliance with applicable state or federal regulations.
(11) 
Stormwater, surface water, groundwater, artisan well water, roof runoff, subsurface drainage, condensate, deionized water, noncontact cooling water, and unpolluted wastewater, unless specifically authorized by the Director.
(12) 
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 wastewater facilities.
(13) 
Medical wastes, sludges, screenings or other residues from the pretreatment of industrial wastes, except as specifically authorized by Director in an industrial treatment permit.
(14) 
Wastewater causing, alone or in conjunction with other sources, the treatment plant's effluent to fail a toxicity test.
(15) 
Detergents, surface-active agents, or other substances which may cause excessive foaming in the POTW.
(16) 
Wastewater causing two readings on an explosion hazard meter at the point of discharge into the POTW, or at any point in the POTW, of more than 50% or any single reading over 10% of the lower explosive limit of the meter.
(17) 
Containing wastes which are not amenable to biological treatment or reduction in existing treatment facilities, specifically nonbiodegradable complex carbon compounds.
(18) 
Trucked or hauled pollutants, except at discharge points designated by the Director and in accordance with § 450-55 of this Part 4.
C. 
Pollutants, substances or wastewater prohibited by this section shall not be processed or stored in such a manner that it could be discharged to the POTW.
The following described substances, materials, waters, pollutants or wastes shall be limited in discharges to municipal systems to concentrations or quantities which will not harm either the sewers, wastewater treatment process or equipment; will not have an adverse effect on the receiving stream or create a hazard in the disposal of sludges generated at the wastewater treatment plant; or will not otherwise endanger lives, limb or public property or constitute a nuisance. The Director may set limitations lower than the limitations established in the regulations below if, in his opinion, such more restrictive limitations are necessary to meet the above objectives. In forming his opinion as to the acceptability, the Director will give consideration to such factors as the quantity of subject waste in relation to flows and velocities in the sewers, materials of construction of the sewers, the wastewater treatment process employed, capacity of the wastewater treatment plant, degree of treatability of the waste in the wastewater treatment plant, method of sludge treatment and disposal and other pertinent factors. The limitations or restrictions on materials or characteristics of waste or wastewater discharged to the sanitary sewer shall be as follows:
A. 
Wastewater shall have a temperature not higher than 104° F. (40° C.).[1]
[1]
Editor's Note: Amended at time of adoption of Code (see Ch. 1, General Provisions, Art. II).
B. 
Wastewater containing free or emulsified hexane soluble materials that are not readily biodegradable shall be limited on analysis to an average of 100 mg/l of total concentration. Where oils or greases are of the nature that they may solidify at temperatures of normal sewage or could create problems in the operation of the wastewater treatment works, additional restrictions may be imposed.
C. 
Any garbage that has not been properly shredded (see § 450-21). Garbage grinders may be connected to sanitary sewers from homes, hotels, institutions, restaurants, hospitals, catering establishments or similar places where garbage originates from the preparation of food in kitchens for the purpose of consumption on the premises or when served by caterers.
D. 
Quantities of flow or concentrations, or both, which constitute a "slug" as defined herein.
E. 
Concentrated dye waste or other wastes high in color which are sufficiently strong to affect the color of the treatment plant effluent.
F. 
Wastewaters containing permissible constituents with BOD, suspended solids, phosphorus or nitrogen in quantities that could cause operational problems at the wastewater treatment plant or exceed the treatment plant design capacity for any of the listed flow constituents.
G. 
Waters or wastes containing substances which are not amenable to treatment or reduction by the wastewater treatment processes employed or are amenable to treatment only to such degree that the wastewater treatment plant effluent cannot meet the requirements of other agencies having jurisdiction over discharge to the receiving waters.
H. 
Any waters or wastes which, by interaction with other waters or wastes in the public sewer system, form suspended solids which interfere with the collection system or create a condition deleterious to structures and treatment processes, unless otherwise shown by a technical evaluation of the specific wastes.
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 § 450-44 of this article and which, in the judgment of the Director, may have a deleterious effect upon the wastewater facilities, processes, equipment, residual sludges or receiving waters or which otherwise create a hazard to life or constitute a public nuisance, the Director may:
A. 
Prohibit the wastes from being discharged to the public sewers.
B. 
Require pretreatment to an acceptable condition for discharge to the public sewers.
C. 
Require a permit to control the quantities and rates of discharge and/or require payment to cover the added cost of handling and treating the wastes not covered by existing taxes or sewer charges.
Stormwater other than that exempted under § 450-43 and all other unpolluted water shall be discharged to such sewers as are specifically designated as storm sewers or to a natural outlet approved by the Director and other regulatory agencies. Unpolluted industrial cooling water or process waters may not be discharged to a storm sewer or natural outlet unless the industry has a National Pollutant Discharge Elimination System discharge permit which is issued by the Maryland Department of the Environment.
When required by the Director, the owner of any property serviced by a building sewer carrying industrial wastes shall install a suitable structure, together with such necessary meters and other appurtenances, in the building sewer to facilitate observation, sampling and measurement of the wastes. Such structure, when required, shall be accessibly and safely located and shall be constructed in accordance with plans approved by the Director. The structure shall be installed by the owner at his expense and shall be maintained by him so as to be safe and accessible to the Director at all times.
The categorical pretreatment standards found at 40 CFR Chapter I, Subchapter N, Parts 405 to 471 are hereby incorporated.
A. 
Where a categorical pretreatment standard is expressed only in terms of either the mass or the concentration of a pollutant in wastewater, the Director may impose equivalent concentration or mass limits in accordance with 40 CFR 403.6(c).
B. 
When wastewater subject to a categorical pretreatment standard is mixed with wastewater not regulated by the same standard, the Director shall impose an alternate limit using the combined waste stream formula in 40 CFR 403.6(e).
C. 
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 the EPA when developing the categorical pretreatment standard.
D. 
A user may obtain a net gross adjustment to a categorical standard in accordance with 40 CFR 403.15.
State pretreatment standards found at Code of Maryland Regulations Title 26, Department of Environment, Subtitle 08, Water Pollution, Chapter 08, titled "Pretreatment Requirements to Control Industrial Users of Publicly Owned Treatment Works," are hereby incorporated.
A. 
The following pollutant limits are established to protect against pass-through and interference. No person shall discharge wastewater containing in excess of the following instantaneous maximum allowable and average daily discharge limits:
[Amended 4-30-2007 by Ord. No. 723-07]
Pollutant
Instantaneous Maximum Allowable
(mg/l)
Daily Average
(mg/l)
Arsenic
n/a
n/a
Benzene
n/a
n/a
Beryllium
n/a
n/a
Biochemical oxygen demand
300
200
Cadmium
n/a
n/a
Chromium, total
n/a
n/a
Copper
n/a
n/a
Cyanide
n/a
n/a
Flow (mgd)
*
*
Lead
n/a
n/a
Mercury
n/a
n/a
Metals, total
n/a
n/a
Nickel
n/a
n/a
Oil and grease
300
100
Phenols, total
n/a
n/a
Selenium
n/a
n/a
Silver
n/a
n/a
Suspended solids
300
200
Zinc
n/a
n/a
*
Limits to be set on a case-by-case basis when a permit is issued.
B. 
The above limits apply at the point where the wastewater is discharged to the POTW. All concentrations for metallic substances are for "total" metal unless indicated otherwise. The Director may impose mass limitations in addition to, or in place of, the concentration-based limitations above.
A. 
The City of Aberdeen reserves the right to establish, by ordinance, wastewater discharge permits with more stringent standards or requirements on discharges to the POTW.
B. 
Nothing in this section shall be construed as preventing any special agreement or permit between the City and any user, including waste haulers, whereby wastewater of unusual character is accepted for treatment should such wastewater be deemed by the City to be acceptable for treatment without harm to the POTW or people operating it, provided that the special agreement or permit does not allow a violation of any appropriate federal pretreatment and/or state requirements.
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 Director may impose mass limitations on users which are using dilution to meet applicable pretreatment standards or requirements or in other cases when the imposition of mass limitations is appropriate.