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TCEQ Class D Water Operator License EXAM
LATEST VERSION WITH 300 QUESTIONS AND
CORRECT DETAILED SOLUTIONS JUST
RELEASED THIS YEAR
TCEQ Class D Water Operator License Exam — 300 Practice Questions
Exam Reference: The Class D Water Operator License is administered by the Texas Commission
on Environmental Quality (TCEQ). The exam covers Basic Water Operations with no experience
required (high school diploma or GED required). All TCEQ occupational licenses require a
minimum score of 70% to pass. Computer-based testing (CBT) is available for the Class D Water
System Operator exam.
SECTION 1: REGULATIONS, COMPLIANCE & RECORDKEEPING (Questions 1–50)
Question 1
According to TCEQ rules, what is the maximum contaminant level (MCL) goal for total coliform
bacteria in a public water system?
A) 5% of monthly samples may be positive
B) No more than 1 sample per month may be positive
C) 0% of samples may be total coliform-positive
D) Total coliform is not regulated
Answer: C
TCEQ follows EPA's Total Coliform Rule; the goal is zero positive samples. For systems collecting
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at least 40 samples per month, no more than 5% may be positive, but for most Class D systems,
any positive requires repeat sampling and may be a violation.
Question 2
The Safe Drinking Water Act is enforced at the federal level by which agency?
A) TCEQ
B) EPA
C) AWWA
D) OSHA
Answer: B
The Environmental Protection Agency (EPA) is the federal regulator of drinking water and
enforces the Safe Drinking Water Act.
Question 3
In Texas, water operator licenses are administered by which agency?
A) EPA
B) TNRCC – TCEQ
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C) AWWA
D) TWUA
Answer: B
The Texas Commission on Environmental Quality (TCEQ), formerly known as TNRCC, administers
water operator licenses in Texas.
Question 4
How long must bacteriological sample results be kept according to state requirements?
A) 1 year
B) 2 years
C) 5 years
D) 10 years
Answer: C
The state requires bacteriological sample results to be kept for 5 years (not 2 years).
Question 5
How long must chemical analysis records be kept according to state requirements?
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A) 2 years
B) 5 years
C) 10 years
D) 20 years
Answer: C
The state requires chemical analysis records to be kept for at least 10 years.
Question 6
How long must a water system keep a copy of each Consumer Confidence Report?
A) 1 year
B) 3 years
C) 5 years
D) 10 years
Answer: C
The EPA requires a water system to keep a copy of each Consumer Confidence Report for at least
5 years.
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SUCCESS!
TCEQ Class D Water Operator License EXAM
LATEST VERSION WITH 300 QUESTIONS AND
CORRECT DETAILED SOLUTIONS JUST
RELEASED THIS YEAR
TCEQ Class D Water Operator License Exam — 300 Practice Questions
Exam Reference: The Class D Water Operator License is administered by the Texas Commission
on Environmental Quality (TCEQ). The exam covers Basic Water Operations with no experience
required (high school diploma or GED required). All TCEQ occupational licenses require a
minimum score of 70% to pass. Computer-based testing (CBT) is available for the Class D Water
System Operator exam.
SECTION 1: REGULATIONS, COMPLIANCE & RECORDKEEPING (Questions 1–50)
Question 1
According to TCEQ rules, what is the maximum contaminant level (MCL) goal for total coliform
bacteria in a public water system?
A) 5% of monthly samples may be positive
B) No more than 1 sample per month may be positive
C) 0% of samples may be total coliform-positive
D) Total coliform is not regulated
Answer: C
TCEQ follows EPA's Total Coliform Rule; the goal is zero positive samples. For systems collecting
1
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at least 40 samples per month, no more than 5% may be positive, but for most Class D systems,
any positive requires repeat sampling and may be a violation.
Question 2
The Safe Drinking Water Act is enforced at the federal level by which agency?
A) TCEQ
B) EPA
C) AWWA
D) OSHA
Answer: B
The Environmental Protection Agency (EPA) is the federal regulator of drinking water and
enforces the Safe Drinking Water Act.
Question 3
In Texas, water operator licenses are administered by which agency?
A) EPA
B) TNRCC – TCEQ
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C) AWWA
D) TWUA
Answer: B
The Texas Commission on Environmental Quality (TCEQ), formerly known as TNRCC, administers
water operator licenses in Texas.
Question 4
How long must bacteriological sample results be kept according to state requirements?
A) 1 year
B) 2 years
C) 5 years
D) 10 years
Answer: C
The state requires bacteriological sample results to be kept for 5 years (not 2 years).
Question 5
How long must chemical analysis records be kept according to state requirements?
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A) 2 years
B) 5 years
C) 10 years
D) 20 years
Answer: C
The state requires chemical analysis records to be kept for at least 10 years.
Question 6
How long must a water system keep a copy of each Consumer Confidence Report?
A) 1 year
B) 3 years
C) 5 years
D) 10 years
Answer: C
The EPA requires a water system to keep a copy of each Consumer Confidence Report for at least
5 years.
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