Page 1 of 108
TEXAS WASTEWATER B EXAM QUESTIONS AND CORRECT
VERIFIED SOLUTIONS LATEST UPDATE THIS YEAR – JUST
RELEASED
TEXAS WASTEWATER B EXAM
MOSTLY TESTED AREAS
1. TCEQ statutes, rules, licensing requirements, facility categorization, operator
responsibilities, and regulatory compliance.
2. Wastewater permits, effluent limitations, monitoring, reporting, violations, sampling,
and permit-condition interpretation.
3. Wastewater characteristics, flow measurement, loading calculations, oxygen demand,
solids, nutrients, and process indicators.
4. Collection systems, sewer components, infiltration/inflow, materials, velocities,
maintenance, and design considerations.
5. Pumping systems, centrifugal pumps, positive-displacement pumps, pump curves,
motors, lift stations, and troubleshooting.
6. Preliminary and primary treatment, screening, grit removal, comminutors,
sedimentation, scum removal, and process control.
7. Biological treatment including activated sludge, trickling filters, RBCs, lagoons,
aeration, microorganisms, and process control.
8. Disinfection, chlorine demand, chlorine dosage, residual, dechlorination, alternative
disinfectants, and safety.
9. Sludge digestion, thickening, conditioning, dewatering, biosolids stabilization,
disposal, reuse, and troubleshooting.
10. Effluent disposal, advanced treatment, sampling, receiving waters, irrigation, process
calculations, and multi-step wastewater mathematics.
1.
A wastewater treatment operator notices that influent flow has increased substantially
following several hours of heavy rainfall. Which condition most likely explains the increase?
, Page 2 of 108
A. Reduced biological oxygen demand caused by dilution
B. Increased infiltration and inflow entering the collection system ✓
C. Increased sludge digestion caused by warmer wastewater
D. Reduced groundwater levels surrounding buried sewer lines
Rationale: Rainfall can introduce groundwater and stormwater through defective pipes, joints,
manholes, illegal connections, and other pathways, producing increased infiltration and inflow.
2.
During activated-sludge operation, which condition generally indicates that microorganisms are
receiving sufficient oxygen for aerobic treatment?
A. Dissolved oxygen remains measurable in the aeration basin ✓
B. Dissolved oxygen remains completely absent throughout aeration
C. Chlorine residual increases inside the biological reactor
D. Influent suspended solids become equal to effluent suspended solids
Rationale: Maintaining appropriate dissolved oxygen allows aerobic microorganisms to
metabolize biodegradable material effectively.
3.
A treatment plant receives 2.0 MGD containing 250 mg/L BOD. Approximately how many
pounds of BOD enter the plant daily?
A. 2,084 pounds
B. 3,125 pounds
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C. 4,170 pounds ✓
D. 5,210 pounds
Rationale: Pounds per day = MGD × mg/L × 8.34. Thus, 2.0 × 250 × 8.34 ≈ 4,170 lb/day.
4.
Why is excessive infiltration and inflow considered undesirable for a wastewater collection and
treatment facility?
A. It always increases wastewater temperature dramatically
B. It can overload hydraulic capacity and unnecessarily increase treatment costs ✓
C. It eliminates the need for pumping stations
D. It permanently decreases groundwater elevations
Rationale: Excessive I/I increases hydraulic loading without necessarily increasing pollutant
loading, potentially exceeding collection or treatment capacity.
5.
A wastewater operator discovers that a permit specifies a maximum effluent concentration that
the facility exceeded during monitoring. What should be considered first?
A. Whether the measured result represents a potential permit violation ✓
B. Whether the treatment plant should immediately stop all flow
C. Whether the laboratory should automatically discard the sample
D. Whether the operator should alter the historical monitoring records
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Rationale: Effluent results must be compared with applicable permit limits, and exceedances
may constitute violations requiring appropriate evaluation and reporting.
6.
Which wastewater characteristic represents the amount of oxygen microorganisms require to
biologically stabilize biodegradable organic matter?
A. Total suspended solids
B. Biological oxygen demand ✓
C. Chlorine residual
D. Alkalinity
Rationale: BOD estimates oxygen consumption associated with microbial degradation of
biodegradable organic material.
7.
A wastewater plant operator wants to determine whether excessive solids are being retained in
an activated-sludge system. Which measurement is especially useful?
A. Mixed liquor suspended solids ✓
B. Chlorine cylinder pressure
C. Influent temperature alone
D. Clearwell water level
Rationale: MLSS measures suspended biological and inert solids within the mixed liquor and is
fundamental to activated-sludge control.
TEXAS WASTEWATER B EXAM QUESTIONS AND CORRECT
VERIFIED SOLUTIONS LATEST UPDATE THIS YEAR – JUST
RELEASED
TEXAS WASTEWATER B EXAM
MOSTLY TESTED AREAS
1. TCEQ statutes, rules, licensing requirements, facility categorization, operator
responsibilities, and regulatory compliance.
2. Wastewater permits, effluent limitations, monitoring, reporting, violations, sampling,
and permit-condition interpretation.
3. Wastewater characteristics, flow measurement, loading calculations, oxygen demand,
solids, nutrients, and process indicators.
4. Collection systems, sewer components, infiltration/inflow, materials, velocities,
maintenance, and design considerations.
5. Pumping systems, centrifugal pumps, positive-displacement pumps, pump curves,
motors, lift stations, and troubleshooting.
6. Preliminary and primary treatment, screening, grit removal, comminutors,
sedimentation, scum removal, and process control.
7. Biological treatment including activated sludge, trickling filters, RBCs, lagoons,
aeration, microorganisms, and process control.
8. Disinfection, chlorine demand, chlorine dosage, residual, dechlorination, alternative
disinfectants, and safety.
9. Sludge digestion, thickening, conditioning, dewatering, biosolids stabilization,
disposal, reuse, and troubleshooting.
10. Effluent disposal, advanced treatment, sampling, receiving waters, irrigation, process
calculations, and multi-step wastewater mathematics.
1.
A wastewater treatment operator notices that influent flow has increased substantially
following several hours of heavy rainfall. Which condition most likely explains the increase?
, Page 2 of 108
A. Reduced biological oxygen demand caused by dilution
B. Increased infiltration and inflow entering the collection system ✓
C. Increased sludge digestion caused by warmer wastewater
D. Reduced groundwater levels surrounding buried sewer lines
Rationale: Rainfall can introduce groundwater and stormwater through defective pipes, joints,
manholes, illegal connections, and other pathways, producing increased infiltration and inflow.
2.
During activated-sludge operation, which condition generally indicates that microorganisms are
receiving sufficient oxygen for aerobic treatment?
A. Dissolved oxygen remains measurable in the aeration basin ✓
B. Dissolved oxygen remains completely absent throughout aeration
C. Chlorine residual increases inside the biological reactor
D. Influent suspended solids become equal to effluent suspended solids
Rationale: Maintaining appropriate dissolved oxygen allows aerobic microorganisms to
metabolize biodegradable material effectively.
3.
A treatment plant receives 2.0 MGD containing 250 mg/L BOD. Approximately how many
pounds of BOD enter the plant daily?
A. 2,084 pounds
B. 3,125 pounds
, Page 3 of 108
C. 4,170 pounds ✓
D. 5,210 pounds
Rationale: Pounds per day = MGD × mg/L × 8.34. Thus, 2.0 × 250 × 8.34 ≈ 4,170 lb/day.
4.
Why is excessive infiltration and inflow considered undesirable for a wastewater collection and
treatment facility?
A. It always increases wastewater temperature dramatically
B. It can overload hydraulic capacity and unnecessarily increase treatment costs ✓
C. It eliminates the need for pumping stations
D. It permanently decreases groundwater elevations
Rationale: Excessive I/I increases hydraulic loading without necessarily increasing pollutant
loading, potentially exceeding collection or treatment capacity.
5.
A wastewater operator discovers that a permit specifies a maximum effluent concentration that
the facility exceeded during monitoring. What should be considered first?
A. Whether the measured result represents a potential permit violation ✓
B. Whether the treatment plant should immediately stop all flow
C. Whether the laboratory should automatically discard the sample
D. Whether the operator should alter the historical monitoring records
, Page 4 of 108
Rationale: Effluent results must be compared with applicable permit limits, and exceedances
may constitute violations requiring appropriate evaluation and reporting.
6.
Which wastewater characteristic represents the amount of oxygen microorganisms require to
biologically stabilize biodegradable organic matter?
A. Total suspended solids
B. Biological oxygen demand ✓
C. Chlorine residual
D. Alkalinity
Rationale: BOD estimates oxygen consumption associated with microbial degradation of
biodegradable organic material.
7.
A wastewater plant operator wants to determine whether excessive solids are being retained in
an activated-sludge system. Which measurement is especially useful?
A. Mixed liquor suspended solids ✓
B. Chlorine cylinder pressure
C. Influent temperature alone
D. Clearwell water level
Rationale: MLSS measures suspended biological and inert solids within the mixed liquor and is
fundamental to activated-sludge control.
