1
TCEQ Wastewater Class D License Prep
Comprehensive Practice Exam Actual
2026/2027 with Detailed Rationales |
Complete Exam-Style Questions – Pass
Guaranteed – A+ Graded
TABLE OF CONTENTS
Section 1 | Regulations & Compliance | Q1 – Q10
Section 2 | Safety & Collection Systems | Q11 – Q23
Section 3 | Treatment Processes | Q24 – Q36
Section 4 | Laboratory, Sampling & Math | Q37 – Q46
Section 5 | NGN-Style Case Analysis & Integrated Scenarios | Q47 – Q50
Instructions: Choose the single best answer. Pass: 35 in 90 minutes.
══════════════════════════════════════
SECTION 1: REGULATIONS & COMPLIANCE Q1 – Q10
══════════════════════════════════════
Question 1 of 50
,2
An operator holds a Class D wastewater license and is the highest-
licensed operator at a facility rated by the TCEQ as a Class C facility.
Identify the regulatory reality of this situation.
A. The facility is in violation because the operator in responsible charge
must hold a license equal to or greater than the facility classification ✓
CORRECT
B. The facility is in compliance as long as the operator works under a
valid TPDES permit
C. The operator may sign the DMRs if approved by the TCEQ regional
office
D. The facility is compliant if the operator is enrolled in classes to
upgrade within 6 months
Correct Answer: A
Rationale: TCEQ requires the operator in responsible charge to hold a
license equal to or greater than the facility classification. A Class D
operator at a Class C facility creates a regulatory violation because the
operator lacks the required level of operational knowledge and legal
authority. On the exam, always match the operator's license grade to
the facility grade or higher.
Question 2 of 50
,3
A TPDES permit specifies a 30-day average BOD5 limit of 30 mg/L and a
7-day average limit of 45 mg/L. The plant records a 7-day average BOD5
of 42 mg/L. Determine the compliance status of the facility.
A. The facility is in violation because the 7-day average exceeds the 30-
day average limit
B. The facility is in compliance because the 7-day average is below its
specific permit limit ✓ CORRECT
C. The facility is in violation because the 7-day average must always be
less than the 30-day average
D. The facility is in compliance only if the daily maximum never
exceeded 30 mg/L
Correct Answer: B
Rationale: A TPDES permit establishes separate limits for 30-day
average and 7-day average, and a 7-day average of 42 mg/L is
compliant if it is below the 7-day limit of 45 mg/L. The common trap is
assuming any 7-day average above the 30-day limit is a violation, but
the permit explicitly authorizes short-term exceedances up to the 7-day
limit. Always check the specific permit limits for each averaging period.
Question 3 of 50
A new wastewater treatment facility is being designed to discharge to a
water body in Texas. Identify the primary TCEQ regulation that
, 4
establishes the effluent limitations for this domestic wastewater
discharge.
A. 30 TAC Chapter 217
B. Texas Water Code Section 26.040
C. 30 TAC Chapter 309 ✓ CORRECT
D. 40 CFR Part 133
Correct Answer: C
Rationale: 30 TAC Chapter 309 contains the domestic wastewater
effluent limitations that dictate the quality of discharge required by
TCEQ permits. 30 TAC Chapter 217 covers design criteria for
construction, not the operational effluent limits. When tested on
effluent limitations, associate Chapter 309 with discharge limits.
Question 4 of 50
A wastewater operator's Class D license is due for renewal. Determine
the continuing education requirement for renewing this license.
A. 10 hours of relevant training
B. 15 hours of relevant training
C. 30 hours of relevant training
D. 20 hours of relevant training ✓ CORRECT
TCEQ Wastewater Class D License Prep
Comprehensive Practice Exam Actual
2026/2027 with Detailed Rationales |
Complete Exam-Style Questions – Pass
Guaranteed – A+ Graded
TABLE OF CONTENTS
Section 1 | Regulations & Compliance | Q1 – Q10
Section 2 | Safety & Collection Systems | Q11 – Q23
Section 3 | Treatment Processes | Q24 – Q36
Section 4 | Laboratory, Sampling & Math | Q37 – Q46
Section 5 | NGN-Style Case Analysis & Integrated Scenarios | Q47 – Q50
Instructions: Choose the single best answer. Pass: 35 in 90 minutes.
══════════════════════════════════════
SECTION 1: REGULATIONS & COMPLIANCE Q1 – Q10
══════════════════════════════════════
Question 1 of 50
,2
An operator holds a Class D wastewater license and is the highest-
licensed operator at a facility rated by the TCEQ as a Class C facility.
Identify the regulatory reality of this situation.
A. The facility is in violation because the operator in responsible charge
must hold a license equal to or greater than the facility classification ✓
CORRECT
B. The facility is in compliance as long as the operator works under a
valid TPDES permit
C. The operator may sign the DMRs if approved by the TCEQ regional
office
D. The facility is compliant if the operator is enrolled in classes to
upgrade within 6 months
Correct Answer: A
Rationale: TCEQ requires the operator in responsible charge to hold a
license equal to or greater than the facility classification. A Class D
operator at a Class C facility creates a regulatory violation because the
operator lacks the required level of operational knowledge and legal
authority. On the exam, always match the operator's license grade to
the facility grade or higher.
Question 2 of 50
,3
A TPDES permit specifies a 30-day average BOD5 limit of 30 mg/L and a
7-day average limit of 45 mg/L. The plant records a 7-day average BOD5
of 42 mg/L. Determine the compliance status of the facility.
A. The facility is in violation because the 7-day average exceeds the 30-
day average limit
B. The facility is in compliance because the 7-day average is below its
specific permit limit ✓ CORRECT
C. The facility is in violation because the 7-day average must always be
less than the 30-day average
D. The facility is in compliance only if the daily maximum never
exceeded 30 mg/L
Correct Answer: B
Rationale: A TPDES permit establishes separate limits for 30-day
average and 7-day average, and a 7-day average of 42 mg/L is
compliant if it is below the 7-day limit of 45 mg/L. The common trap is
assuming any 7-day average above the 30-day limit is a violation, but
the permit explicitly authorizes short-term exceedances up to the 7-day
limit. Always check the specific permit limits for each averaging period.
Question 3 of 50
A new wastewater treatment facility is being designed to discharge to a
water body in Texas. Identify the primary TCEQ regulation that
, 4
establishes the effluent limitations for this domestic wastewater
discharge.
A. 30 TAC Chapter 217
B. Texas Water Code Section 26.040
C. 30 TAC Chapter 309 ✓ CORRECT
D. 40 CFR Part 133
Correct Answer: C
Rationale: 30 TAC Chapter 309 contains the domestic wastewater
effluent limitations that dictate the quality of discharge required by
TCEQ permits. 30 TAC Chapter 217 covers design criteria for
construction, not the operational effluent limits. When tested on
effluent limitations, associate Chapter 309 with discharge limits.
Question 4 of 50
A wastewater operator's Class D license is due for renewal. Determine
the continuing education requirement for renewing this license.
A. 10 hours of relevant training
B. 15 hours of relevant training
C. 30 hours of relevant training
D. 20 hours of relevant training ✓ CORRECT
