TEXAS WASTEWATER CLASS A EXAM VERSION A
AND B OVER 280 QUESTIONS WITH DETAILED
VERIFIED 2025/2026 GRADED A+
TEXAS WASTEWATER CLASS A EXAM VERSION A
AND B OVER 280 QUESTIONS WITH DETAILED
VERIFIED 2025/2026 GRADED A+
1. Seeding of BOD samples is necessary when samples (All of the above) have a
chlorine residual, have previously been chlorinated, have been subjected to high
temperatures, contain high or low pH industrial wastes.
2. When is blue-green algae most dominant on a pond treatment system?
**Summer**
3. A 30-inch diameter wastewater interceptor is flowing half-full at about two fps. The
approximate volume of wastewater flowing through the pipe is:
**c. 2,200 gallons per minute**
4. A one-cylinder reciprocating sludge pump with a 10-inch bore and a 5-inch stroke
pumps at 50 cycles per minute. How many minutes must the pump operate to pump
5,000 gallons of sludge?
**d. 60 minutes**
5. If an existing centrifugal pump motor is replaced with a motor with 25% more speed,
the horsepower required will increase by approximately:
**1.95 times**
6. When must TCEQ be notified about expansions of a treatment facility?
,**Before construction**
7. In an anaerobic digester, the gas content should be:
**70% methane, 30% carbon dioxide**
8. The temperature of an anaerobic digester should be maintained at a minimum of:
**95° F**
9. What type of wastewater treatment operates in the endogenous bacteria growth
phase?
**Extended aeration**
10. Why is recirculation needed in a trickling filter?
**All of the above (keep media wet, further reduce BOD, and all c)**
11. What type of fire extinguisher would be used on a de-energized electrical control
panel?
**Class C (and A or D)**
12. Disinfection with chlorine is most effective at a pH of:
**6.0**
13. The biomass on a normal functioning RBC appears as:
**Grey to brown, 0.05 to 0.1 inch thick**
14. The sludge from a primary clarifier should contain what percent solids?
**4% to 6%**
,15. What is eutrophication in a pond system?
**Causes algae blooms and is caused by nitrogen and phosphorus enrichment**
16. How often should pH meters be calibrated?
**Daily**
17. In Texas, pH meters are required to be calibrated on how many buffers?
**Two**
18. An industrial complex discharges 500 pounds BOD/day. The population equivalent is
approximately:
**2,941 persons**
19. The parameters of the BOD test are:
**5 days at 20°C**
20. Standard Dimension Ratio in PVC pipe is defined as:
**Ratio of OD pipe diameter to wall thickness**
21. How should shoring be removed from a trench?
**Up from the bottom up**
22. In low-pressure sewer systems with grinder pumps, the lift station is considered part
of the:
**Collection system and the responsibility of the utility**
23. Effective communication depends on:
**Being a good listener**
, 24. When designing a wastewater collection system, the engineer considers the
population for how many years in the future?
**50 years**
25. According to 30 TAC Chapter 317, all pipe and fittings used in wastewater pressure
shall have a minimum psi pressure rating of:
**150**
26. The minimum velocity of flow in a wastewater line should be:
**2.0 fps**
27. At a construction site, as roadway speed increases, the spacing between cones and
barricades should:
**Increase**
28. The major cause of wastewater line stoppages is:
**Roots and grease**
29. Carbon monoxide poisoning symptoms include:
**Tightness in the chest, nausea, drowsiness, headache (all of the above)**
30. The smallest pipe size for air recirculation of a self-priming centrifugal pump is:
**1 inch**
31. Dangerous gases in confined spaces may not be detected by senses because:
**All of the above (no odor, deaden sense of smell, displace oxygen)**
AND B OVER 280 QUESTIONS WITH DETAILED
VERIFIED 2025/2026 GRADED A+
TEXAS WASTEWATER CLASS A EXAM VERSION A
AND B OVER 280 QUESTIONS WITH DETAILED
VERIFIED 2025/2026 GRADED A+
1. Seeding of BOD samples is necessary when samples (All of the above) have a
chlorine residual, have previously been chlorinated, have been subjected to high
temperatures, contain high or low pH industrial wastes.
2. When is blue-green algae most dominant on a pond treatment system?
**Summer**
3. A 30-inch diameter wastewater interceptor is flowing half-full at about two fps. The
approximate volume of wastewater flowing through the pipe is:
**c. 2,200 gallons per minute**
4. A one-cylinder reciprocating sludge pump with a 10-inch bore and a 5-inch stroke
pumps at 50 cycles per minute. How many minutes must the pump operate to pump
5,000 gallons of sludge?
**d. 60 minutes**
5. If an existing centrifugal pump motor is replaced with a motor with 25% more speed,
the horsepower required will increase by approximately:
**1.95 times**
6. When must TCEQ be notified about expansions of a treatment facility?
,**Before construction**
7. In an anaerobic digester, the gas content should be:
**70% methane, 30% carbon dioxide**
8. The temperature of an anaerobic digester should be maintained at a minimum of:
**95° F**
9. What type of wastewater treatment operates in the endogenous bacteria growth
phase?
**Extended aeration**
10. Why is recirculation needed in a trickling filter?
**All of the above (keep media wet, further reduce BOD, and all c)**
11. What type of fire extinguisher would be used on a de-energized electrical control
panel?
**Class C (and A or D)**
12. Disinfection with chlorine is most effective at a pH of:
**6.0**
13. The biomass on a normal functioning RBC appears as:
**Grey to brown, 0.05 to 0.1 inch thick**
14. The sludge from a primary clarifier should contain what percent solids?
**4% to 6%**
,15. What is eutrophication in a pond system?
**Causes algae blooms and is caused by nitrogen and phosphorus enrichment**
16. How often should pH meters be calibrated?
**Daily**
17. In Texas, pH meters are required to be calibrated on how many buffers?
**Two**
18. An industrial complex discharges 500 pounds BOD/day. The population equivalent is
approximately:
**2,941 persons**
19. The parameters of the BOD test are:
**5 days at 20°C**
20. Standard Dimension Ratio in PVC pipe is defined as:
**Ratio of OD pipe diameter to wall thickness**
21. How should shoring be removed from a trench?
**Up from the bottom up**
22. In low-pressure sewer systems with grinder pumps, the lift station is considered part
of the:
**Collection system and the responsibility of the utility**
23. Effective communication depends on:
**Being a good listener**
, 24. When designing a wastewater collection system, the engineer considers the
population for how many years in the future?
**50 years**
25. According to 30 TAC Chapter 317, all pipe and fittings used in wastewater pressure
shall have a minimum psi pressure rating of:
**150**
26. The minimum velocity of flow in a wastewater line should be:
**2.0 fps**
27. At a construction site, as roadway speed increases, the spacing between cones and
barricades should:
**Increase**
28. The major cause of wastewater line stoppages is:
**Roots and grease**
29. Carbon monoxide poisoning symptoms include:
**Tightness in the chest, nausea, drowsiness, headache (all of the above)**
30. The smallest pipe size for air recirculation of a self-priming centrifugal pump is:
**1 inch**
31. Dangerous gases in confined spaces may not be detected by senses because:
**All of the above (no odor, deaden sense of smell, displace oxygen)**
