Texas Wastewater Class A Exam Questions
With Accurate Answers 2025\2026 A+
Grade
Seeding of BOD samples is necessary when samples
- accurate answers-(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?
- accurate answers-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
- accurate answers-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
- accurate answers-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
- accurate answers-95 percent
When must TCEQ be notified about expansions of a treatment facility?
- accurate answers-Before construction
In an anaerobic digester, the percentage of methane and carbon dioxide gas
content should be
- accurate answers-70% methane, 30% carbon dioxide
The temperature of an anaerobic digester should be maintained at a minimum
of
- accurate answers-95° F
,What type of wastewater treatment operates in the endogenous bacteria
growth phase?
- accurate answers-Extended air
Why is recirculation needed in a trickling filter?
- accurate answers-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?
- accurate answers-Class A Class C (a and d)
Disinfection with chlorine is the most effective at a pH of
- accurate answers-6.0
The biomass on a normal functioning RBC has what appearance?
- accurate answers-Grey to brown and 0.05 to 0.1 inch thick
The sludge from a primary clarifier should percent solids?
- accurate answers-4% to 6%
What is eutrophication in a pond system?
- accurate answers-Enrichment with nitrogen and phosphorous Causes algae
blooms (b and c)
How often should pH meters be calibrated?
- accurate answers-Daily
In Texas, pH meters are required to be calibrated on how many buffers?
- accurate answers-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
- accurate answers-2941
The parameters of the BOD test are
- accurate answers-5 days at 20° Centigrade
, Standard Dimension Ratio in pvc pipe is defined as
- accurate answers-Ratio of OD pipe diameter to wall thickness
How should shoring be removed from a trench?
- accurate answers-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
- accurate answers-part of the collection system and the responsibility of the
utility
Effective communication depends on
- accurate answers-being a good listener
When designing a wastewater collection system, the engineer considers the
population for how many years in the future?
- accurate answers-50
According to 30 TAC Chapter 317, all pipe and fittings used in wastewater
pressure shall have a minimum psi pressure rating of
- accurate answers-150
The minimum velocity of flow in a wastewater line should be
- accurate answers-2.0 fps
At a construction job site, as the roadway speed increases, the spacing
between cones and barricades should
- accurate answers-increase
The major cause of wastewater line stoppages is
- accurate answers-roots and grease
Carbon monoxide (CO) poisoning symptoms are
- accurate answers-tightness in the chest nausea drowsiness and headache (all
of the above)
With Accurate Answers 2025\2026 A+
Grade
Seeding of BOD samples is necessary when samples
- accurate answers-(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?
- accurate answers-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
- accurate answers-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
- accurate answers-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
- accurate answers-95 percent
When must TCEQ be notified about expansions of a treatment facility?
- accurate answers-Before construction
In an anaerobic digester, the percentage of methane and carbon dioxide gas
content should be
- accurate answers-70% methane, 30% carbon dioxide
The temperature of an anaerobic digester should be maintained at a minimum
of
- accurate answers-95° F
,What type of wastewater treatment operates in the endogenous bacteria
growth phase?
- accurate answers-Extended air
Why is recirculation needed in a trickling filter?
- accurate answers-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?
- accurate answers-Class A Class C (a and d)
Disinfection with chlorine is the most effective at a pH of
- accurate answers-6.0
The biomass on a normal functioning RBC has what appearance?
- accurate answers-Grey to brown and 0.05 to 0.1 inch thick
The sludge from a primary clarifier should percent solids?
- accurate answers-4% to 6%
What is eutrophication in a pond system?
- accurate answers-Enrichment with nitrogen and phosphorous Causes algae
blooms (b and c)
How often should pH meters be calibrated?
- accurate answers-Daily
In Texas, pH meters are required to be calibrated on how many buffers?
- accurate answers-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
- accurate answers-2941
The parameters of the BOD test are
- accurate answers-5 days at 20° Centigrade
, Standard Dimension Ratio in pvc pipe is defined as
- accurate answers-Ratio of OD pipe diameter to wall thickness
How should shoring be removed from a trench?
- accurate answers-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
- accurate answers-part of the collection system and the responsibility of the
utility
Effective communication depends on
- accurate answers-being a good listener
When designing a wastewater collection system, the engineer considers the
population for how many years in the future?
- accurate answers-50
According to 30 TAC Chapter 317, all pipe and fittings used in wastewater
pressure shall have a minimum psi pressure rating of
- accurate answers-150
The minimum velocity of flow in a wastewater line should be
- accurate answers-2.0 fps
At a construction job site, as the roadway speed increases, the spacing
between cones and barricades should
- accurate answers-increase
The major cause of wastewater line stoppages is
- accurate answers-roots and grease
Carbon monoxide (CO) poisoning symptoms are
- accurate answers-tightness in the chest nausea drowsiness and headache (all
of the above)
