Texas Wastewater Class A Exam Questions With
100% Correct Answers
1. Seeding of BOD samples is necessary when samples - ANSWER: (All of the
above) have a chlorine residual, have a previously been chlorinated, have been
subjected to high temperatures, contain high or low pH industrial wastes
2. When is blue-green algae the most dominant on a pond treatment system? -
ANSWER: Summer
3. A 30-inch diameter wastewater interceptor is observed to be flowing half-full at
about two fps. The approximate volume of wastewater flowing through the pipe is
3.14x1.25 x 1.25 x 2 = 4.9 cfs x 449 = 2,200 gpm - ANSWER: 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 a rate of 50 cycles per minute. How many minutes must the pump be
operated to pump 5,000 gallons of sludge? 3.14x0.416 x 0.416 x0.416 x 50 x7.48
= 84.5 gpm 5000 gal = 59,2min 84.5 gpm b. 29 - ANSWER: 60 minutes
5. If an existing centrifugal pump motor is replaced with a motor with 25 percent
more speed, the motor horsepower required will increase by 1.25 x 1.25 x 1.25 =
1.95 - ANSWER: 95 percent
6. When must TCEQ be notified about expansions of a treatment facility? -
ANSWER: Before construction
7. In an anaerobic digester, the percentage of methane and carbon dioxide gas
content should be - ANSWER: 70% methane, 30% carbon dioxide
8. The temperature of an anaerobic digester should be maintained at a minimum of
- ANSWER: 95° F
9. What type of wastewater treatment operates in the endogenous bacteria growth
phase? - ANSWER: Extended air
10. Why is recirculation needed in a trickling filter? - ANSWER: Keep the media
wet Further reduce BOD All of the above (a, b, and c)
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11. What type of fire extinguisher would be used on an electrical control panel that
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has been de-energized? - ANSWER: Class A Class C (a and d)
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12. Disinfection with chlorine is the most effective at a pH of - ANSWER: 6.0 &^%$%^
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,Texas Wastewater Class A Exam Questions With
100% Correct Answers
13. The biomass on a normal functioning RBC has what appearance? - ANSWER:
Grey to brown and 0.05 to 0.1 inch thick
14. The sludge from a primary clarifier should percent solids? - ANSWER: 4% to
6%
15. What is eutrophication in a pond system? - ANSWER: Enrichment with
nitrogen and phosphorous Causes algae blooms (b and c)
16. How often should pH meters be calibrated? - ANSWER: Daily
17. In Texas, pH meters are required to be calibrated on how many buffers? -
ANSWER: two
18. An industrial complex has a BOD discharge to the POTW of 500 pounds per day.
The population equivalent of this industry is 500 lbs = 2,941 0.17 lbs BOD person
- ANSWER: 2941
19. The parameters of the BOD test are - ANSWER: 5 days at 20° Centigrade
20. Standard Dimension Ratio in pvc pipe is defined as - ANSWER: Ratio of OD
pipe diameter to wall thickness
21. How should shoring be removed from a trench? - ANSWER: up from the
bottom up
22. In low pressure sewer systems where each tap must have a grinder pump lift
station, station is considered to be - ANSWER: part of the collection system
and the responsibility of the utility
23. Effective communication depends on - ANSWER: being a good listener
24. When designing a wastewater collection system, the engineer considers the
population for how many years in the future? - ANSWER: 50
25. According to 30 TAC Chapter 317, all pipe and fittings used in wastewater #$%^&*(
pressure shall have a minimum psi pressure rating of - ANSWER: 150 (*&^%$$
%^&*()(*
26. The minimum velocity of flow in a wastewater line should be - ANSWER: 2.0
fps &^%$%^
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, Texas Wastewater Class A Exam Questions With
100% Correct Answers
27. At a construction job site, as the roadway speed increases, the spacing between
cones and barricades should - ANSWER: increase
28. The major cause of wastewater line stoppages is - ANSWER: roots and
grease
29. Carbon monoxide (CO) poisoning symptoms are - ANSWER: tightness in the
chest nausea drowsiness and headache (all of the above)
30. The smallest pipe size for air recirculation of a self-priming centrifugal pump is -
ANSWER: 1 inch
31. Dangerous gases in a confined space may not be detected with the physical
senses because - ANSWER: some gases have no odor some gases may
deaden the sense of smell some gases may displace the oxygen (all of the
above)
32. What are the dangerous gases a collection system worker might come into
contact with? - ANSWER: CO2 CO НaS CH4 (all of the above)
33. On a construction job site, equipment booms must maintain at least how many
feet of clearance from overhead electric lines? - ANSWER: 10
34. How should trench shoring be installed? - ANSWER: to above the top of the
trench
35. When setting work goals for an employee, the goals should be - ANSWER:
accompanied by an action plan
36. According to Chapter 317, Design Criteria, a manhole can be installed within 9
feet of an existing waterline if - ANSWER: the manhole is completely watertight
and tested for no leakage
37. As the population of a collection system increases, the ratio of peak flow to
average daily flow will - ANSWER: decrease
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38. Motivating workers to do a better job is best done by - ANSWER: letting
(*&^%$$
workers participate in setting goals
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39. One important element of a good communicator is - ANSWER: being a good &^%$%^
listener &*()(*&^
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)(*&^%$
%^&*()(*
&^%$%^
&*()(*&^
100% Correct Answers
1. Seeding of BOD samples is necessary when samples - ANSWER: (All of the
above) have a chlorine residual, have a previously been chlorinated, have been
subjected to high temperatures, contain high or low pH industrial wastes
2. When is blue-green algae the most dominant on a pond treatment system? -
ANSWER: Summer
3. A 30-inch diameter wastewater interceptor is observed to be flowing half-full at
about two fps. The approximate volume of wastewater flowing through the pipe is
3.14x1.25 x 1.25 x 2 = 4.9 cfs x 449 = 2,200 gpm - ANSWER: c. 2,200 gallons
per minute
4. A one-cylinder reciprocating sludge pump with a 10-inch bore and a 5-inch stroke
pumps at a rate of 50 cycles per minute. How many minutes must the pump be
operated to pump 5,000 gallons of sludge? 3.14x0.416 x 0.416 x0.416 x 50 x7.48
= 84.5 gpm 5000 gal = 59,2min 84.5 gpm b. 29 - ANSWER: 60 minutes
5. If an existing centrifugal pump motor is replaced with a motor with 25 percent
more speed, the motor horsepower required will increase by 1.25 x 1.25 x 1.25 =
1.95 - ANSWER: 95 percent
6. When must TCEQ be notified about expansions of a treatment facility? -
ANSWER: Before construction
7. In an anaerobic digester, the percentage of methane and carbon dioxide gas
content should be - ANSWER: 70% methane, 30% carbon dioxide
8. The temperature of an anaerobic digester should be maintained at a minimum of
- ANSWER: 95° F
9. What type of wastewater treatment operates in the endogenous bacteria growth
phase? - ANSWER: Extended air
10. Why is recirculation needed in a trickling filter? - ANSWER: Keep the media
wet Further reduce BOD All of the above (a, b, and c)
#$%^&*(
11. What type of fire extinguisher would be used on an electrical control panel that
(*&^%$$
has been de-energized? - ANSWER: Class A Class C (a and d)
%^&*()(*
12. Disinfection with chlorine is the most effective at a pH of - ANSWER: 6.0 &^%$%^
&*()(*&^
%$%^&*
)(*&^%$
%^&*()(*
&^%$%^
&*()(*&^
,Texas Wastewater Class A Exam Questions With
100% Correct Answers
13. The biomass on a normal functioning RBC has what appearance? - ANSWER:
Grey to brown and 0.05 to 0.1 inch thick
14. The sludge from a primary clarifier should percent solids? - ANSWER: 4% to
6%
15. What is eutrophication in a pond system? - ANSWER: Enrichment with
nitrogen and phosphorous Causes algae blooms (b and c)
16. How often should pH meters be calibrated? - ANSWER: Daily
17. In Texas, pH meters are required to be calibrated on how many buffers? -
ANSWER: two
18. An industrial complex has a BOD discharge to the POTW of 500 pounds per day.
The population equivalent of this industry is 500 lbs = 2,941 0.17 lbs BOD person
- ANSWER: 2941
19. The parameters of the BOD test are - ANSWER: 5 days at 20° Centigrade
20. Standard Dimension Ratio in pvc pipe is defined as - ANSWER: Ratio of OD
pipe diameter to wall thickness
21. How should shoring be removed from a trench? - ANSWER: up from the
bottom up
22. In low pressure sewer systems where each tap must have a grinder pump lift
station, station is considered to be - ANSWER: part of the collection system
and the responsibility of the utility
23. Effective communication depends on - ANSWER: being a good listener
24. When designing a wastewater collection system, the engineer considers the
population for how many years in the future? - ANSWER: 50
25. According to 30 TAC Chapter 317, all pipe and fittings used in wastewater #$%^&*(
pressure shall have a minimum psi pressure rating of - ANSWER: 150 (*&^%$$
%^&*()(*
26. The minimum velocity of flow in a wastewater line should be - ANSWER: 2.0
fps &^%$%^
&*()(*&^
%$%^&*
)(*&^%$
%^&*()(*
&^%$%^
&*()(*&^
, Texas Wastewater Class A Exam Questions With
100% Correct Answers
27. At a construction job site, as the roadway speed increases, the spacing between
cones and barricades should - ANSWER: increase
28. The major cause of wastewater line stoppages is - ANSWER: roots and
grease
29. Carbon monoxide (CO) poisoning symptoms are - ANSWER: tightness in the
chest nausea drowsiness and headache (all of the above)
30. The smallest pipe size for air recirculation of a self-priming centrifugal pump is -
ANSWER: 1 inch
31. Dangerous gases in a confined space may not be detected with the physical
senses because - ANSWER: some gases have no odor some gases may
deaden the sense of smell some gases may displace the oxygen (all of the
above)
32. What are the dangerous gases a collection system worker might come into
contact with? - ANSWER: CO2 CO НaS CH4 (all of the above)
33. On a construction job site, equipment booms must maintain at least how many
feet of clearance from overhead electric lines? - ANSWER: 10
34. How should trench shoring be installed? - ANSWER: to above the top of the
trench
35. When setting work goals for an employee, the goals should be - ANSWER:
accompanied by an action plan
36. According to Chapter 317, Design Criteria, a manhole can be installed within 9
feet of an existing waterline if - ANSWER: the manhole is completely watertight
and tested for no leakage
37. As the population of a collection system increases, the ratio of peak flow to
average daily flow will - ANSWER: decrease
#$%^&*(
38. Motivating workers to do a better job is best done by - ANSWER: letting
(*&^%$$
workers participate in setting goals
%^&*()(*
39. One important element of a good communicator is - ANSWER: being a good &^%$%^
listener &*()(*&^
%$%^&*
)(*&^%$
%^&*()(*
&^%$%^
&*()(*&^
