IDEM WASTEWATER RULES AND REGULATIONS
EXAM 80 QUESTIONS & CORRECT ANSWERS
LATEST 2026/2027
What are the goals of the state regarding water quality? - ANSWER-The goals of
the state regarding water quality are to restore and maintain the chemical, physical
and biological integrity of the waters of the state.
All surface waters of the state are designated for _____(a)____ . Also, all waters of
the state, except limited use waters, must be capable of supporting a well-balanced,
warm water _____(b)____ community - ANSWER-(a) Full-body contact
recreation
(b) Aquatic.
All waters at all times and at all places, including the mixing zone, shall meet the
minimum conditions of being free from substances, materials, floating debris, oil,
or scum attributable to municipal, industrial, agricultural, and other land use
practices, or other discharges. What are the four types of undesirable conditions or
substances described in the rule? - ANSWER-(a) Substances that will settle to
form putrescent or otherwise objectionable deposits.
(b) Substances that are in amounts sufficient to be unsightly or deleterious.
(c) Substances that produce color, visible oil sheen, odor, or other conditions in
such degree as to create a nuisance.
(d) Substances which are in amounts sufficient to be acutely toxic to, or otherwise
severely injure or kill aquatic life, other animals, plants, or humans.
My wastewater treatment plant receives brine wastes from water softeners. Do I
have to be concerned about the salt content of my discharge? - ANSWER-Yes. The
,salt discharge could increase the dissolved solids concentration of your discharge.
The state water quality standards require that dissolved solids shall not exceed 750
mg/l in any waters.
What is the minimum dissolved oxygen requirement in surface waters of the State
of Indiana? - ANSWER-5 mg/l per calendar day and shall not be less than four
milligrams per liter at any time
What are the conditions for temperature in the waters of the state (except for Lake
Michigan)? - ANSWER-(a) There shall be no abnormal temperature changes that
may adversely affect aquatic life unless caused by natural conditions.
(b) The normal daily and seasonal temperature fluctuations that existed before the
addition of heat due to other than natural causes shall be maintained.
(c) The maximum temperature rise at any time or place above natural temperatures
shall not exceed 5°F in streams and 3°F in lakes and reservoirs.
(d) Water temperatures shall not exceed the maximum limits in Table 6-4 during
more than one percent of the hours in the twelve-month period ending with any
month. At no time shall the water temperature at such locations exceed the
maximum limits in Table 6-4 by more than 3°F.
What are the requirements for reporting spills? - ANSWER-A spill must be
reported to IDEM as soon as possible, but within two hours of discovery (at the
latest).
What is the purpose of 327 IAC, Article 4, Wastewater Treatment Facilities;
Overload Condition? - ANSWER-The prevention of water pollution and the
protection of wastewater treatment infrastructure.
What is a "sanitary sewer"? - ANSWER-Conveys liquid and water-carried wastes
from residences, commercial buildings, industrial plants, and institutions to a
treatment plant.
, Define a "water pollution treatment/control facility" - ANSWER-Any equipment,
device, unit, structure, etc., that is used to control, prevent, pretreat, or treat any
discharge or threatened discharge of pollutants into any waters of the state of
Indiana, including surface and subsurface waters and public or private sewerage
systems
What is meant by "waters of the state of Indiana" or "waters of the state"? -
ANSWER-"Such accumulations of water, surface and underground, natural and
artificial, public and private, or parts thereof, that are wholly or partially within,
flow through, or border upon this state.
What is a sewer connection ban ("sewer ban"), and when may IDEM impose one?
- ANSWER-A sewer ban is a legal document issued by IDEM which prohibits the
addition of any new sources of wastewater into collection system/treatment facility
until the cause of overloading has been corrected.
What are the criteria used by IDEM to issue a sewer ban early warning (SBEW)? -
ANSWER-When IDEM determines a semipublic facility or POTW has reached or
is approaching 90% of its hydraulic or organic design capacity,
What is meant by "Best Management Practices", or "BMPs"? - ANSWER-BMPs
are actions to prevent or reduce the pollution of waters of the state, including:
(a) Schedules of activities.
(b) Prohibitions of practice.
(c) Treatment requirements.
(d) Operation and maintenance procedures.
(e) Use of containment facilities.
(f) Other management practices
EXAM 80 QUESTIONS & CORRECT ANSWERS
LATEST 2026/2027
What are the goals of the state regarding water quality? - ANSWER-The goals of
the state regarding water quality are to restore and maintain the chemical, physical
and biological integrity of the waters of the state.
All surface waters of the state are designated for _____(a)____ . Also, all waters of
the state, except limited use waters, must be capable of supporting a well-balanced,
warm water _____(b)____ community - ANSWER-(a) Full-body contact
recreation
(b) Aquatic.
All waters at all times and at all places, including the mixing zone, shall meet the
minimum conditions of being free from substances, materials, floating debris, oil,
or scum attributable to municipal, industrial, agricultural, and other land use
practices, or other discharges. What are the four types of undesirable conditions or
substances described in the rule? - ANSWER-(a) Substances that will settle to
form putrescent or otherwise objectionable deposits.
(b) Substances that are in amounts sufficient to be unsightly or deleterious.
(c) Substances that produce color, visible oil sheen, odor, or other conditions in
such degree as to create a nuisance.
(d) Substances which are in amounts sufficient to be acutely toxic to, or otherwise
severely injure or kill aquatic life, other animals, plants, or humans.
My wastewater treatment plant receives brine wastes from water softeners. Do I
have to be concerned about the salt content of my discharge? - ANSWER-Yes. The
,salt discharge could increase the dissolved solids concentration of your discharge.
The state water quality standards require that dissolved solids shall not exceed 750
mg/l in any waters.
What is the minimum dissolved oxygen requirement in surface waters of the State
of Indiana? - ANSWER-5 mg/l per calendar day and shall not be less than four
milligrams per liter at any time
What are the conditions for temperature in the waters of the state (except for Lake
Michigan)? - ANSWER-(a) There shall be no abnormal temperature changes that
may adversely affect aquatic life unless caused by natural conditions.
(b) The normal daily and seasonal temperature fluctuations that existed before the
addition of heat due to other than natural causes shall be maintained.
(c) The maximum temperature rise at any time or place above natural temperatures
shall not exceed 5°F in streams and 3°F in lakes and reservoirs.
(d) Water temperatures shall not exceed the maximum limits in Table 6-4 during
more than one percent of the hours in the twelve-month period ending with any
month. At no time shall the water temperature at such locations exceed the
maximum limits in Table 6-4 by more than 3°F.
What are the requirements for reporting spills? - ANSWER-A spill must be
reported to IDEM as soon as possible, but within two hours of discovery (at the
latest).
What is the purpose of 327 IAC, Article 4, Wastewater Treatment Facilities;
Overload Condition? - ANSWER-The prevention of water pollution and the
protection of wastewater treatment infrastructure.
What is a "sanitary sewer"? - ANSWER-Conveys liquid and water-carried wastes
from residences, commercial buildings, industrial plants, and institutions to a
treatment plant.
, Define a "water pollution treatment/control facility" - ANSWER-Any equipment,
device, unit, structure, etc., that is used to control, prevent, pretreat, or treat any
discharge or threatened discharge of pollutants into any waters of the state of
Indiana, including surface and subsurface waters and public or private sewerage
systems
What is meant by "waters of the state of Indiana" or "waters of the state"? -
ANSWER-"Such accumulations of water, surface and underground, natural and
artificial, public and private, or parts thereof, that are wholly or partially within,
flow through, or border upon this state.
What is a sewer connection ban ("sewer ban"), and when may IDEM impose one?
- ANSWER-A sewer ban is a legal document issued by IDEM which prohibits the
addition of any new sources of wastewater into collection system/treatment facility
until the cause of overloading has been corrected.
What are the criteria used by IDEM to issue a sewer ban early warning (SBEW)? -
ANSWER-When IDEM determines a semipublic facility or POTW has reached or
is approaching 90% of its hydraulic or organic design capacity,
What is meant by "Best Management Practices", or "BMPs"? - ANSWER-BMPs
are actions to prevent or reduce the pollution of waters of the state, including:
(a) Schedules of activities.
(b) Prohibitions of practice.
(c) Treatment requirements.
(d) Operation and maintenance procedures.
(e) Use of containment facilities.
(f) Other management practices
