Wastewater and its characteristics.
BIOCHEMICAL OXYGEN DEMAND (BOD)
The quantity of oxygen utilized in the biochemical oxidation
of organic matter under standard laboratory procedure in five days
at 20° C., expressed in milligrams per liter.
FLOATABLE OIL
Oil, fat, or grease in a physical state such that it will
separate by gravity from wastewater by treatment in an approved pretreatment
facility. A wastewater shall be considered free of floatable fat if
it is properly pretreated and the wastewater does not interfere with
the collection system.
GARBAGE
Solid wastes from the domestic and commercial preparation,
cooking, and dispensing of food, and from the handling, storage and
sale of food.
INDUSTRIAL WASTE
Any solid, liquid or gaseous substance discharged, permitted
to flow or escaping from any industrial, manufacturing, commercial
or business establishment or process or from the development, recovery
or processing of any natural resource as distinct from sanitary sewage.
MAJOR CONTRIBUTING INDUSTRY
An industrial user of the publicly owned treatment works
that has a flow of 50,000 gallons or more per average work day; or
has a flow greater than 10% of the flow carried by the Village system
receiving the waste; or has in its waste a toxic pollutant in toxic
amounts as defined in standards issued under Section 307(a) of the
Federal Act; or is found by the permit-issuing authority, in connection
with the issuance of the NPDES permit to the publicly owned treatment
works receiving the waste, to have significant impact, either singly
or in combination with other contributing industries, on that treatment
works or upon the quality of effluent from that treatment works.
MILLIGRAMS PER LITER
A unit of the concentration of water or wastewater constituent.
It is 0.001 g of the constituent in 1,000 ml of water. It has replaced
the unit formerly used commonly, parts per million, to which it is
approximately equivalent, in reporting the results of water and wastewater
analysis.
pH
The logarithm (base 10) of the reciprocal of the hydrogen-ion
concentration expressed by one of the procedures outlined in the IEPA
Division of Laboratories Manual of Laboratory Methods.
POPULATION EQUIVALENT
A term used to evaluate the impact of industrial or other
waste on a treatment works or stream. One population equivalent is
100 gallons of sewage per day, containing 217 pounds of BOD and 0.25
pound of suspended solids.
PROPERLY SHREDDED GARBAGE
The wastes from the preparation, cooking, and dispensing
of food that have been shredded to such a degree that all particles
will be carried freely under the flow conditions normally prevailing
in public sewers, with no particle greater than 1/2 inch (1.27 centimeters)
in any dimension.
SEWAGE
Used interchangeably with "wastewater."
SLUG
Any discharge of water, sewage or industrial waste which
in concentration of any given constituent or in quantity of flow exceeds
for any period of duration longer than 15 minutes more than five times
the average twenty-four-hour concentration or flows during normal
operation.
SUSPENDED SOLIDS (SS)
Solids that either float on the surface of or are in suspension
in water, sewage, or industrial waste, and which are removable by
a laboratory filtration device. Quantitative determination of suspended
solids shall be made in accordance with procedures set forth in the
IEPA Division of Laboratories Manual of Laboratory Methods.
UNPOLLUTED WATER
Water quality equal to or better than the effluent criteria
in effect or water that would not cause violation of receiving water
quality standards and would not be benefited by discharge to the sanitary
sewers and wastewater treatment facilities provided.
WASTEWATER
The spent water of the community. It may be a combination
of the liquid and water-carried wastes from residences, commercial
buildings, industrial plants, and institutions, together with any
groundwater, surface water, and stormwater that may be present.