Texas Wastewater Class A, B & C Exam | Newest
Actual Exam Questions & Correct Detailed Answers
(Verified) | 2025 Update
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
When is blue-green algae the most dominant on a pond treatment
system? - ANSWER >>>>Summer
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
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
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
When must TCEQ be notified about expansions of a treatment
facility? - ANSWER >>>>Before construction
,In an anaerobic digester, the percentage of methane and carbon
dioxide gas content should be - ANSWER >>>>70% methane,
30% carbon dioxide
The temperature of an anaerobic digester should be maintained
at a minimum of - ANSWER >>>>95° F
What type of wastewater treatment operates in the endogenous
bacteria growth phase? - ANSWER >>>>Extended air
Why is recirculation needed in a trickling filter? - ANSWER
>>>>Keep the media wet Further reduce BOD All of the above (a,
b, and c)
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)
Disinfection with chlorine is the most effective at a pH of -
ANSWER >>>>6.0
The biomass on a normal functioning RBC has what appearance?
- ANSWER >>>>Grey to brown and 0.05 to 0.1 inch thick
The sludge from a primary clarifier should percent solids? -
ANSWER >>>>4% to 6%
What is eutrophication in a pond system? - ANSWER
>>>>Enrichment with nitrogen and phosphorous Causes algae
blooms (b and c)
How often should pH meters be calibrated? - ANSWER
>>>>Daily
,In Texas, pH meters are required to be calibrated on how many
buffers? - ANSWER >>>>two
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
The parameters of the BOD test are - ANSWER >>>>5 days at
20° Centigrade
Standard Dimension Ratio in pvc pipe is defined as - ANSWER
>>>>Ratio of OD pipe diameter to wall thickness
How should shoring be removed from a trench? - ANSWER
>>>>up from the bottom up
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
Effective communication depends on - ANSWER >>>>being a
good listener
When designing a wastewater collection system, the engineer
considers the population for how many years in the future? -
ANSWER >>>>50
According to 30 TAC Chapter 317, all pipe and fittings used in
wastewater pressure shall have a minimum psi pressure rating of
- ANSWER >>>>150
The minimum velocity of flow in a wastewater line should be -
ANSWER >>>>2.0 fps
, At a construction job site, as the roadway speed increases, the
spacing between cones and barricades should - ANSWER
>>>>increase
The major cause of wastewater line stoppages is - ANSWER
>>>>roots and grease
Carbon monoxide (CO) poisoning symptoms are - ANSWER
>>>>tightness in the chest nausea drowsiness and headache (all
of the above)
The smallest pipe size for air recirculation of a self-priming
centrifugal pump is - ANSWER >>>>1 inch
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)
What are the dangerous gases a collection system worker might
come into contact with? - ANSWER >>>>CO2 CO НaS CH4 (all
of the above)
On a construction job site, equipment booms must maintain at
least how many feet of clearance from overhead electric lines? -
ANSWER >>>>10
How should trench shoring be installed? - ANSWER >>>>to
above the top of the trench
When setting work goals for an employee, the goals should be -
ANSWER >>>>accompanied by an action plan
According to Chapter 317, Design Criteria, a manhole can be
installed within 9 feet of an existing waterline if - ANSWER
Actual Exam Questions & Correct Detailed Answers
(Verified) | 2025 Update
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
When is blue-green algae the most dominant on a pond treatment
system? - ANSWER >>>>Summer
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
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
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
When must TCEQ be notified about expansions of a treatment
facility? - ANSWER >>>>Before construction
,In an anaerobic digester, the percentage of methane and carbon
dioxide gas content should be - ANSWER >>>>70% methane,
30% carbon dioxide
The temperature of an anaerobic digester should be maintained
at a minimum of - ANSWER >>>>95° F
What type of wastewater treatment operates in the endogenous
bacteria growth phase? - ANSWER >>>>Extended air
Why is recirculation needed in a trickling filter? - ANSWER
>>>>Keep the media wet Further reduce BOD All of the above (a,
b, and c)
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)
Disinfection with chlorine is the most effective at a pH of -
ANSWER >>>>6.0
The biomass on a normal functioning RBC has what appearance?
- ANSWER >>>>Grey to brown and 0.05 to 0.1 inch thick
The sludge from a primary clarifier should percent solids? -
ANSWER >>>>4% to 6%
What is eutrophication in a pond system? - ANSWER
>>>>Enrichment with nitrogen and phosphorous Causes algae
blooms (b and c)
How often should pH meters be calibrated? - ANSWER
>>>>Daily
,In Texas, pH meters are required to be calibrated on how many
buffers? - ANSWER >>>>two
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
The parameters of the BOD test are - ANSWER >>>>5 days at
20° Centigrade
Standard Dimension Ratio in pvc pipe is defined as - ANSWER
>>>>Ratio of OD pipe diameter to wall thickness
How should shoring be removed from a trench? - ANSWER
>>>>up from the bottom up
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
Effective communication depends on - ANSWER >>>>being a
good listener
When designing a wastewater collection system, the engineer
considers the population for how many years in the future? -
ANSWER >>>>50
According to 30 TAC Chapter 317, all pipe and fittings used in
wastewater pressure shall have a minimum psi pressure rating of
- ANSWER >>>>150
The minimum velocity of flow in a wastewater line should be -
ANSWER >>>>2.0 fps
, At a construction job site, as the roadway speed increases, the
spacing between cones and barricades should - ANSWER
>>>>increase
The major cause of wastewater line stoppages is - ANSWER
>>>>roots and grease
Carbon monoxide (CO) poisoning symptoms are - ANSWER
>>>>tightness in the chest nausea drowsiness and headache (all
of the above)
The smallest pipe size for air recirculation of a self-priming
centrifugal pump is - ANSWER >>>>1 inch
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)
What are the dangerous gases a collection system worker might
come into contact with? - ANSWER >>>>CO2 CO НaS CH4 (all
of the above)
On a construction job site, equipment booms must maintain at
least how many feet of clearance from overhead electric lines? -
ANSWER >>>>10
How should trench shoring be installed? - ANSWER >>>>to
above the top of the trench
When setting work goals for an employee, the goals should be -
ANSWER >>>>accompanied by an action plan
According to Chapter 317, Design Criteria, a manhole can be
installed within 9 feet of an existing waterline if - ANSWER
