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.).
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.
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.