Illinois Administrative Code › Title 35 - ENVIRONMENTAL PROTECTION › Part 302 - WATER QUALITY STANDARDS › Subpart A - GENERAL WATER QUALITY PROVISIONS › Section 302.100 - Definitions

Current through Register Vol. 48, No. 28, July 12, 2024
Unless otherwise specified, the definitions of the
				  Environmental Protection Act (Act) [415 ILCS 5 ]
				  and 35 Ill. Adm. Code 301 apply to this Part. As used in this Part, each of the
				  following definitions has the specified meaning.
"Acute Toxicity" means the capacity of any substance or
				  combination of substances to cause mortality or other adverse effects in an
				  organism resulting from a single or short-term exposure to the
				  substance.
"Adverse Effect" means any gross or overt effect on an
				  organism, including reversible histopathological damage, severe convulsions,
				  irreversible functional impairment, and lethality, as well as any non-overt
				  effect on an organism resulting in functional impairment or pathological
				  lesions that may affect the performance of the whole organism, or that reduces
				  an organism's ability to respond to an additional challenge.
"Chronic Toxicity" means the capacity of any substance or
				  combination of substances to cause injurious or debilitating effects in an
				  organism that result from exposure for a time period representing a substantial
				  portion of the natural life cycle of that organism, including the growth phase,
				  the reproductive phases, or such critical portions of the natural life cycle of
				  that organism.
"Criterion" means the numerical concentration of one or more
				  toxic substances derived in compliance with the procedures in Subpart F that,
				  if not exceeded, would assure compliance with the narrative toxicity standard
				  of Section 302.210.
"Early Life Stages" of fish means the pre-hatch embryonic
				  period, the post-hatch free embryo or yolk-sac fry, and the larval period,
				  during which the organism feeds. Juvenile fish, which are anatomically similar
				  to adults, are not considered to be an early life stage.
"Hardness" means a water quality parameter or characteristic
				  consisting of the sum of calcium and magnesium concentrations expressed in
				  terms of equivalent milligrams per liter as calcium carbonate. Hardness is
				  measured in compliance with methods specified in
				  40 CFR
				  136, incorporated by reference in 35 Ill.
				  Adm. Code 301.106.
"Mixing Zone" means a portion of the waters of the State
				  identified as a region within which mixing is allowed under Section
				  302.102(d).
"Thermocline" means the plane of maximum rate of decrease of
				  temperature with respect to depth in a thermally stratified body of
				  water.
"Total Residual Chlorine" or "TRC" means those substances
				  that include combined and uncombined forms of both chlorine and bromine and
				  that are expressed, by convention, as an equivalent concentration of molecular
				  chlorine. TRC is measured in compliance with methods specified in
				  40 CFR
				  136, incorporated by reference in 35 Ill.
				  Adm. Code 301.106.
"Toxic Substance" means a chemical substance that causes
				  adverse effects in humans, or in aquatic or terrestrial animal or plant life.
				  Toxic substances include those substances listed in
				  40 CFR
				  302.4, incorporated by reference in 35 Ill.
				  Adm. Code 301.106, or any "chemical substance" as defined by the Illinois
				  Chemical Safety Act [430 ILCS 45 ]
"ZID" or "Zone of Initial Dilution" means a portion of a
				  mixing zone, identified pursuant to Section
				  302.102(e),
				  within which acute toxicity standards need not be met.