Indiana Water Operator Certification
Study Guide | Drinking Water
Treatment & Distribution Exam Prep
2026/2027
,A factory provides drinking water from its well for 35 C. Non-transient Non-community
employees Monday through Friday most weeks of the
year. What kind of public water supply is it?
A. Community
B. Non-community
C. Non-transient Non-community
D. None of the above
A community of 1,500 people pumps water directly from A. DSS
2 wells into a 25,000- gallon standpipe. How would IDEM
classify the distribution system?
A. DSS
B. DSM
C. DSL
D. WT-6
A community of 1,500 people pumps water directly from B. WT2
2 wells into a 25,000- gallon stand pipe decides to add
Chlorine for disinfection of its water. How would IDEM
classify the water treatment system?
A. WT1
B. WT2
C. WT5
D. DSS
How does an operator become an operator-in- B. The operator is designated by the owner or governing body of a water
responsible-charge? treatment plant or water distribution system
A. The operator petitions the Commissioner of IDEM
B. The operator is designated by the owner or governing
body of a water treatment plant or water distribution
system
C. The operator is appointed by the IDEM field inspector
D. None of the above
An Operator-in-Training (OIT) may serve as operator in B. False
responsible charge.
A. True
B. False
,A grandparented operator must fulfill the same A. True
continuing education requirements as an operator who
has received certification by examination.
A. True
B. False
Wellhead protection is mandatory for which type of A. Community
public water system?
A. Community
B. Noncommunity
C. Both of the above
D. None of the above
IDEM will issue a Notice of Violation if a water system B. False
operator, or other official, contacts the agency too
frequently.
A. True
B. False
What is the minimum number of coliform samples all A. 1
water systems must collect each month?
A. 1
B. 2
C. 3
D. 4
A foot of head (water height) produces how many A. .4333
pounds per square inch of pressure?
A. .4333
B. 2.574
C. 3.141
D. 5.333
Pressure tanks should be sized to avoid excessive pump A. True
cycling.
A. True
B. False
, What is a cross connection? D. An actual or potential connection between a public water supply and a source
A. The process of connecting a hose to the large port of of contamination or pollution
a fire hydrant
B. Use of an electrically-powered tool in a moist
environment
C. Failure to turn off the power to a well when repacking
a gland
D. An actual or potential connection between a public
water supply and a source of contamination or pollution
Under the Lead and Copper Rule, what percentage of D. 90%
tested water services must be below 0.015 Mg/l Lead
(Pb)?
A. 60%
B. 70%
C. 80%
D. 90%
What does "first draw" mean when collecting lead and A. Taking a sample after the water has been in contact with the plumbing for at
copper samples? least 6 hours
A. Taking a sample after the water has been in contact
with the plumbing for at least 6 hours
B. Drawing a water sample from the faucet nearest the
water meter
C. Carrying the sample bottle in a leather holster affixed
to the technician's belt
D. None of the above
In the event you are notified that a coliform sample was C. 24 hours
positive (Primary Contamination), how many hours do you
have to obtain a repeat sample?
A. 8
B. 12
C. 24
D. 48
What is the minimum air gap required to prevent a cross D. 1 foot
connection?
A. 1 inch
B. 4 inches
C. 8 inches
D. 1 foot
Synthetic organic compounds (SOCs) are found in: B. Pesticides and herbicides
A. Industrial solvents
B. Pesticides and herbicides
C. Naturally occurring contaminants
D. All of the above
May IDEM grant a chemical contaminant monitoring A. Yes
waiver for asbestos?
A. Yes
B. No
Study Guide | Drinking Water
Treatment & Distribution Exam Prep
2026/2027
,A factory provides drinking water from its well for 35 C. Non-transient Non-community
employees Monday through Friday most weeks of the
year. What kind of public water supply is it?
A. Community
B. Non-community
C. Non-transient Non-community
D. None of the above
A community of 1,500 people pumps water directly from A. DSS
2 wells into a 25,000- gallon standpipe. How would IDEM
classify the distribution system?
A. DSS
B. DSM
C. DSL
D. WT-6
A community of 1,500 people pumps water directly from B. WT2
2 wells into a 25,000- gallon stand pipe decides to add
Chlorine for disinfection of its water. How would IDEM
classify the water treatment system?
A. WT1
B. WT2
C. WT5
D. DSS
How does an operator become an operator-in- B. The operator is designated by the owner or governing body of a water
responsible-charge? treatment plant or water distribution system
A. The operator petitions the Commissioner of IDEM
B. The operator is designated by the owner or governing
body of a water treatment plant or water distribution
system
C. The operator is appointed by the IDEM field inspector
D. None of the above
An Operator-in-Training (OIT) may serve as operator in B. False
responsible charge.
A. True
B. False
,A grandparented operator must fulfill the same A. True
continuing education requirements as an operator who
has received certification by examination.
A. True
B. False
Wellhead protection is mandatory for which type of A. Community
public water system?
A. Community
B. Noncommunity
C. Both of the above
D. None of the above
IDEM will issue a Notice of Violation if a water system B. False
operator, or other official, contacts the agency too
frequently.
A. True
B. False
What is the minimum number of coliform samples all A. 1
water systems must collect each month?
A. 1
B. 2
C. 3
D. 4
A foot of head (water height) produces how many A. .4333
pounds per square inch of pressure?
A. .4333
B. 2.574
C. 3.141
D. 5.333
Pressure tanks should be sized to avoid excessive pump A. True
cycling.
A. True
B. False
, What is a cross connection? D. An actual or potential connection between a public water supply and a source
A. The process of connecting a hose to the large port of of contamination or pollution
a fire hydrant
B. Use of an electrically-powered tool in a moist
environment
C. Failure to turn off the power to a well when repacking
a gland
D. An actual or potential connection between a public
water supply and a source of contamination or pollution
Under the Lead and Copper Rule, what percentage of D. 90%
tested water services must be below 0.015 Mg/l Lead
(Pb)?
A. 60%
B. 70%
C. 80%
D. 90%
What does "first draw" mean when collecting lead and A. Taking a sample after the water has been in contact with the plumbing for at
copper samples? least 6 hours
A. Taking a sample after the water has been in contact
with the plumbing for at least 6 hours
B. Drawing a water sample from the faucet nearest the
water meter
C. Carrying the sample bottle in a leather holster affixed
to the technician's belt
D. None of the above
In the event you are notified that a coliform sample was C. 24 hours
positive (Primary Contamination), how many hours do you
have to obtain a repeat sample?
A. 8
B. 12
C. 24
D. 48
What is the minimum air gap required to prevent a cross D. 1 foot
connection?
A. 1 inch
B. 4 inches
C. 8 inches
D. 1 foot
Synthetic organic compounds (SOCs) are found in: B. Pesticides and herbicides
A. Industrial solvents
B. Pesticides and herbicides
C. Naturally occurring contaminants
D. All of the above
May IDEM grant a chemical contaminant monitoring A. Yes
waiver for asbestos?
A. Yes
B. No
