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WASTEWATER CLASS B TEXAS 2025
UPDATED ACTUAL EXAM WITH
CORRECT SOLUTIONS.
The name of the State Agency responsible for enforcing
pollution control laws in Texas - correct answer- Texas
Commission of Environmental Quality
The term pathogenic means - correct answer- Capable of
causing disease
The minimum separation between sewer lines and potable
water lines is - correct answer- 9 feet
A licensed wastewater operator is a professional - correct
answer- consistently does best job possible, practices personal
safety, strives to improve job knowledge, strives to keep the
plant and collection system in the best appearance and working
order
An important step in testing a sample for Total Suspended
Solids is - correct answer- Filtering a sample
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The Biochemical oxygen Demand (BOD) of a sample is based
on - correct answer- Measuring the dissolved oxygen (DO)
used
The results of Biochemical Oxygen Demand (BOD) sample
taken at a treatment plant tells the operator - correct answer-
How the plant was operating 5 days ago
Which of the following are dangerous gasses that are likely to
be present in lift stations and manholes? - correct answer-
Natural gas, gasoline fumes, hydrogen sulfide and carbon
dioxide
A preferred hydraulic method of cleaning sewer lines is - correct
answer- Hydro Jet Cleaner
Ways to reduce bad odors coming from a collection system -
correct answer- routinely cleaning slow running or low flow
lines, adding chlorine or hydrogen peroxide to the collection
system
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Types of pipe that are commonly used in wastewater collection
system - correct answer- ductile iron, Poly Vinyl Chloride (PVC)
Before entering a confined space a worker should - correct
answer- Use approved monitoring device and check for the
presence of dangerous gasses, ventilate the space with a
blower, wear a safety harness and attach a life line
A properly designed and operated primary sedimentation tank
should remove _____ percent of incoming BOD - correct
answer- 30-40%
Devices that may be used to determine the level of sewage in a
lift station - correct answer- air bubbler, floats, electrodes,
Acoustic (sonic)
What is the most important role of aerobic bacteria in the
treatment of wastewater? - correct answer- decompose organic
matter
The hydraulic loading of a trickling filter may be determined by -
correct answer- flow rate and filter area
, 4 | Page
These can be used to dewater sludge - correct answer- belt
press, drying beds, solid bowl centrifuge, gravity thickener
Most important to providing adequate sewage treatment in a
stabilization pond - correct answer- sunlight, algae, bacteria
and time
Offensive and objectionable odors which sometimes occur in
trickling filters usually indicate - correct answer- septic
conditions are present
Dissolved Oxygen (DO) in aeration tank of an activated sludge
plant should be maintained at or about - correct answer- 2 to 4
mg/L
Contributes to the infiltration in a collection system - correct
answer- breaks in the main lines, high ground water levels,
heavy rains, hydro jet cleaning plugged mains
When a centrifuge pump loses prime the - correct answer-
pump is no longer moving liquid
WASTEWATER CLASS B TEXAS 2025
UPDATED ACTUAL EXAM WITH
CORRECT SOLUTIONS.
The name of the State Agency responsible for enforcing
pollution control laws in Texas - correct answer- Texas
Commission of Environmental Quality
The term pathogenic means - correct answer- Capable of
causing disease
The minimum separation between sewer lines and potable
water lines is - correct answer- 9 feet
A licensed wastewater operator is a professional - correct
answer- consistently does best job possible, practices personal
safety, strives to improve job knowledge, strives to keep the
plant and collection system in the best appearance and working
order
An important step in testing a sample for Total Suspended
Solids is - correct answer- Filtering a sample
,2 | Page
The Biochemical oxygen Demand (BOD) of a sample is based
on - correct answer- Measuring the dissolved oxygen (DO)
used
The results of Biochemical Oxygen Demand (BOD) sample
taken at a treatment plant tells the operator - correct answer-
How the plant was operating 5 days ago
Which of the following are dangerous gasses that are likely to
be present in lift stations and manholes? - correct answer-
Natural gas, gasoline fumes, hydrogen sulfide and carbon
dioxide
A preferred hydraulic method of cleaning sewer lines is - correct
answer- Hydro Jet Cleaner
Ways to reduce bad odors coming from a collection system -
correct answer- routinely cleaning slow running or low flow
lines, adding chlorine or hydrogen peroxide to the collection
system
,3 | Page
Types of pipe that are commonly used in wastewater collection
system - correct answer- ductile iron, Poly Vinyl Chloride (PVC)
Before entering a confined space a worker should - correct
answer- Use approved monitoring device and check for the
presence of dangerous gasses, ventilate the space with a
blower, wear a safety harness and attach a life line
A properly designed and operated primary sedimentation tank
should remove _____ percent of incoming BOD - correct
answer- 30-40%
Devices that may be used to determine the level of sewage in a
lift station - correct answer- air bubbler, floats, electrodes,
Acoustic (sonic)
What is the most important role of aerobic bacteria in the
treatment of wastewater? - correct answer- decompose organic
matter
The hydraulic loading of a trickling filter may be determined by -
correct answer- flow rate and filter area
, 4 | Page
These can be used to dewater sludge - correct answer- belt
press, drying beds, solid bowl centrifuge, gravity thickener
Most important to providing adequate sewage treatment in a
stabilization pond - correct answer- sunlight, algae, bacteria
and time
Offensive and objectionable odors which sometimes occur in
trickling filters usually indicate - correct answer- septic
conditions are present
Dissolved Oxygen (DO) in aeration tank of an activated sludge
plant should be maintained at or about - correct answer- 2 to 4
mg/L
Contributes to the infiltration in a collection system - correct
answer- breaks in the main lines, high ground water levels,
heavy rains, hydro jet cleaning plugged mains
When a centrifuge pump loses prime the - correct answer-
pump is no longer moving liquid
