TEXAS WASTEWATER CLASS B FINAL
EXAM STUDY GUIDE 2025/2026
COMPLETE QUESTIONS AND CORRECT
DETAILED ANSWERS WITH RATIONALES ||
100% GUARANTEED PASS
<RECENT VERSION>
1. The name of the State Agency responsible for enforcing pollution control
laws in Texas - ANSWER ✓ Texas Commission of Environmental Quality
2. The term pathogenic means - ANSWER ✓ Capable of causing disease
3. The minimum separation between sewer lines and potable water lines is -
ANSWER ✓ 9 feet
4. A licensed wastewater operator is a professional - 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
5. An important step in testing a sample for Total Suspended Solids is -
ANSWER ✓ Filtering a sample
6. The Biochemical oxygen Demand (BOD) of a sample is based on -
ANSWER ✓ Measuring the dissolved oxygen (DO) used
7. The results of Biochemical Oxygen Demand (BOD) sample taken at a
treatment plant tells the operator - ANSWER ✓ How the plant was operating
5 days ago
,8. Which of the following are dangerous gasses that are likely to be present in
lift stations and manholes? - ANSWER ✓ Natural gas, gasoline fumes,
hydrogen sulfide and carbon dioxide
9. A preferred hydraulic method of cleaning sewer lines is - ANSWER ✓
Hydro Jet Cleaner
10.Ways to reduce bad odors coming from a collection system - ANSWER ✓
routinely cleaning slow running or low flow lines, adding chlorine or
hydrogen peroxide to the collection system
11.Types of pipe that are commonly used in wastewater collection system -
ANSWER ✓ ductile iron, Poly Vinyl Chloride (PVC)
12.Before entering a confined space a worker should - 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
13.Common operating problems with a trickling filter include - ANSWER ✓
Ponding, Filter files, Odors, Clogging of Nozzles, & Snails
14.Wastewater Stabilization Ponds are an approved process for wastewater
treatment. Organic loading of Stabilization Ponds is typically - ANSWER ✓
35 lbs BOD/Acre/Day with a minimum of 30 days detention time
15.Wastewater Stabilization Ponds work through a complex process which
includes - ANSWER ✓ Sunlight, Oxygen, Nutrients, Algae, and Bacteria
16.Facultative Lagoons have two zones of treatment - ANSWER ✓ an aerobic
surface layer and an anaerobic bottom layer
17.Typically one could expect ____ % BOD removal in a Facultative Lagoon -
ANSWER ✓ 50
18.Aerated Lagoons rely on ______ to provide ____and _____ - ANSWER ✓
Mechanical aeration/ Aeration & mixing
,19.The most common method of dewatering and drying sludge is - ANSWER
✓ drying bed
20.Digester gas typically contains about ________%_______ - ANSWER ✓
65-75% methane
21.The depth of sludge drawn to a drying bed should be - ANSWER ✓
Approximately 9 inches
22.Newly hired personnel have _________to become licensed. - ANSWER ✓ 1
year
23.Force Mains and fittings must have a pressure rating of at least - ANSWER
✓ 150 psi
24.Most pumping stations and electrical equipment used today in wastewater
collection or treatment is ________ and typically either _______ or
_________ volts - ANSWER ✓ A.C. (Alternating Current) & 220 or 440
and in some cases A.C. (Alternating Current) & 100 or 208
25.To avoid electrical shock, the operator should ________ if they are
experiencing equipment failures or power related issues - ANSWER ✓ Refer
the problem to a trained electrical repairperson and do not attempt to check
fuses or open the disconnect box and Notify the power provider and let them
send out a serviceman to assure the problem is not on the provider's side.
26.When using Hydraulic Hydro Jetting sewer cleaning equipment the operator
will want to go from a _______ manhole and clean toward the stoppage to
avoid _________. - ANSWER ✓ Clear or open / Forcing sewage into
customer homes or businesses
27.The Activated Sludge Process can produce a high degree of treatment.
Typically one could expect a ______to_______% BOD removal - ANSWER
✓ 90 to 99%
28.The Activated Sludge plant has five (5) Critical Components. They are -
ANSWER ✓ Oxygen supply, Aeration tanks, Clarifiers, Return & Waste
, 29.The Activated Sludge process is an ________process. - ANSWER ✓
Aerobic
30.In the activated sludge process aeration tanks provide the space necessary to
_______, ________, & _______ and return biological solids. - ANSWER ✓
Mix, aerate, & Hold Influent
31.In the active sludge process, Utilization is the process where - ANSWER ✓
Food supply is changed into a liquid state for use
32.In the activated sludge process, Stabilization is - ANSWER ✓ Wastes
biologically converted to water, carbon dioxide, or new cells
33.In the activated sludge process, the _______ is called the heart of the
activated sludge process. - ANSWER ✓ Clarifier
34.In the activated sludge process, factors that will influence the operation of
the final clarifier are - ANSWER ✓ Loading, solids applied, settling,
thickness of solids, rate of return & Wasting
35.In the activated sludge process, the clarifier will concentrate return sludge
and waste sludge about ___ to__ times the solids concentration of the mixed
liquor - ANSWER ✓ two (2) to four (4)
36.In the activated sludge process, for the clarifier to do its job, the ____ must
be retained long enough to allow ______ to settle and liquid to rise. -
ANSWER ✓ water/ solids
37.In the activated sludge process, as more mixed liquor flows to the clarifier,
the thickness of the sludge blanket will - ANSWER ✓ Increase as solids
accumulate
38.In the activated sludge process, biological solids from the bottom of the
clarifier must be returned to the aeration basin for re-seed. This process is
accomplished by - ANSWER ✓ Air lift pumps, centrifugal pumps,
Diaphragm pumps, Screw pumps & Gravity Flow
EXAM STUDY GUIDE 2025/2026
COMPLETE QUESTIONS AND CORRECT
DETAILED ANSWERS WITH RATIONALES ||
100% GUARANTEED PASS
<RECENT VERSION>
1. The name of the State Agency responsible for enforcing pollution control
laws in Texas - ANSWER ✓ Texas Commission of Environmental Quality
2. The term pathogenic means - ANSWER ✓ Capable of causing disease
3. The minimum separation between sewer lines and potable water lines is -
ANSWER ✓ 9 feet
4. A licensed wastewater operator is a professional - 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
5. An important step in testing a sample for Total Suspended Solids is -
ANSWER ✓ Filtering a sample
6. The Biochemical oxygen Demand (BOD) of a sample is based on -
ANSWER ✓ Measuring the dissolved oxygen (DO) used
7. The results of Biochemical Oxygen Demand (BOD) sample taken at a
treatment plant tells the operator - ANSWER ✓ How the plant was operating
5 days ago
,8. Which of the following are dangerous gasses that are likely to be present in
lift stations and manholes? - ANSWER ✓ Natural gas, gasoline fumes,
hydrogen sulfide and carbon dioxide
9. A preferred hydraulic method of cleaning sewer lines is - ANSWER ✓
Hydro Jet Cleaner
10.Ways to reduce bad odors coming from a collection system - ANSWER ✓
routinely cleaning slow running or low flow lines, adding chlorine or
hydrogen peroxide to the collection system
11.Types of pipe that are commonly used in wastewater collection system -
ANSWER ✓ ductile iron, Poly Vinyl Chloride (PVC)
12.Before entering a confined space a worker should - 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
13.Common operating problems with a trickling filter include - ANSWER ✓
Ponding, Filter files, Odors, Clogging of Nozzles, & Snails
14.Wastewater Stabilization Ponds are an approved process for wastewater
treatment. Organic loading of Stabilization Ponds is typically - ANSWER ✓
35 lbs BOD/Acre/Day with a minimum of 30 days detention time
15.Wastewater Stabilization Ponds work through a complex process which
includes - ANSWER ✓ Sunlight, Oxygen, Nutrients, Algae, and Bacteria
16.Facultative Lagoons have two zones of treatment - ANSWER ✓ an aerobic
surface layer and an anaerobic bottom layer
17.Typically one could expect ____ % BOD removal in a Facultative Lagoon -
ANSWER ✓ 50
18.Aerated Lagoons rely on ______ to provide ____and _____ - ANSWER ✓
Mechanical aeration/ Aeration & mixing
,19.The most common method of dewatering and drying sludge is - ANSWER
✓ drying bed
20.Digester gas typically contains about ________%_______ - ANSWER ✓
65-75% methane
21.The depth of sludge drawn to a drying bed should be - ANSWER ✓
Approximately 9 inches
22.Newly hired personnel have _________to become licensed. - ANSWER ✓ 1
year
23.Force Mains and fittings must have a pressure rating of at least - ANSWER
✓ 150 psi
24.Most pumping stations and electrical equipment used today in wastewater
collection or treatment is ________ and typically either _______ or
_________ volts - ANSWER ✓ A.C. (Alternating Current) & 220 or 440
and in some cases A.C. (Alternating Current) & 100 or 208
25.To avoid electrical shock, the operator should ________ if they are
experiencing equipment failures or power related issues - ANSWER ✓ Refer
the problem to a trained electrical repairperson and do not attempt to check
fuses or open the disconnect box and Notify the power provider and let them
send out a serviceman to assure the problem is not on the provider's side.
26.When using Hydraulic Hydro Jetting sewer cleaning equipment the operator
will want to go from a _______ manhole and clean toward the stoppage to
avoid _________. - ANSWER ✓ Clear or open / Forcing sewage into
customer homes or businesses
27.The Activated Sludge Process can produce a high degree of treatment.
Typically one could expect a ______to_______% BOD removal - ANSWER
✓ 90 to 99%
28.The Activated Sludge plant has five (5) Critical Components. They are -
ANSWER ✓ Oxygen supply, Aeration tanks, Clarifiers, Return & Waste
, 29.The Activated Sludge process is an ________process. - ANSWER ✓
Aerobic
30.In the activated sludge process aeration tanks provide the space necessary to
_______, ________, & _______ and return biological solids. - ANSWER ✓
Mix, aerate, & Hold Influent
31.In the active sludge process, Utilization is the process where - ANSWER ✓
Food supply is changed into a liquid state for use
32.In the activated sludge process, Stabilization is - ANSWER ✓ Wastes
biologically converted to water, carbon dioxide, or new cells
33.In the activated sludge process, the _______ is called the heart of the
activated sludge process. - ANSWER ✓ Clarifier
34.In the activated sludge process, factors that will influence the operation of
the final clarifier are - ANSWER ✓ Loading, solids applied, settling,
thickness of solids, rate of return & Wasting
35.In the activated sludge process, the clarifier will concentrate return sludge
and waste sludge about ___ to__ times the solids concentration of the mixed
liquor - ANSWER ✓ two (2) to four (4)
36.In the activated sludge process, for the clarifier to do its job, the ____ must
be retained long enough to allow ______ to settle and liquid to rise. -
ANSWER ✓ water/ solids
37.In the activated sludge process, as more mixed liquor flows to the clarifier,
the thickness of the sludge blanket will - ANSWER ✓ Increase as solids
accumulate
38.In the activated sludge process, biological solids from the bottom of the
clarifier must be returned to the aeration basin for re-seed. This process is
accomplished by - ANSWER ✓ Air lift pumps, centrifugal pumps,
Diaphragm pumps, Screw pumps & Gravity Flow
