1|Page
TEXAS WASTEWATER CLASS C TEST 2026/2027
EXAM QUESTIONS ACCURATE ACTUAL
EXAM||VERIFIED EXAM!!! FREQUENTLY TESTED
QUESTIONS WITH DETAILED ANSWERS |
GUARANTEED PASS | GRADED A+||NEWEST EXAM!!!
Which device may be used to determine the level of
sewage in a lift station?
a. Air bubbler tube
b. Parshall Flume
c. Altitude Valve
d. Air Actuated Valve
e. All the above - Answers-A
What is the most important role of aerobic bacteria in the
treatment of wastewater?
a. Enhance organic matter
b. Decompose organic matter
c. Introduce workers to dangerous diseases
d. Enhance oxygen production
e. Produces Odor and Offensive Smells - Answers-B
,2|Page
The hydraulic loading of a trickling filter may be
determined by -
a. BOD and depth of filter media
b. Organic loading and filter volume
c. Total pounds of BOD removed
d. Total pounds of suspended solids applied daily
e. Flow rate and filter area - Answers-E
Which of the following is typically used to dewater sludge?
a. Belt press
b. Drying beds
c. Solid bowl centrifuge
d. Gravity thickener
e. All the above - Answers-E
Which of the following are the most important to providing
adequate sewage treatment in a stabilization pond?
a. Protozoa, rotifers and turtles
b. Sunlight, algae, bacteria, and Time
c. Aeration, Sedimentation, and Chlorine Contact
d. Nitrification, Sedimentation, Recirculation, & Detention
,3|Page
e. Blowers, Diffusers, & Ultraviolet Disinfection - Answers-
B
Offensive and objectionable odors which sometimes occur
in trickling filters usually indicate that -
a. The filter should be backwashed
b. The flow is too great for the filter area
c. Chlorinator is not working properly & algae is growing
on the media
d. Septic conditions are present
e. All the above - Answers-D
Dissolved Oxygen (DO) in the aeration tank of an
activated sludge plant should be maintained at or about -
a. 1 to 2 mg/L
b. 2 to 3 mg/L
c. 2 to 4 mg/L
d. 4 to 6 mg/L
e. 0.5 to 0.75 mg/L - Answers-C
, 4|Page
Which of the following would contribute to infiltration in a
collection system?
a. Breaks in the main lines
b. High ground water levels
c. Heavy rains
d. Hydro jet cleaning plugged mains
e. a, b, & c - Answers-E
When a centrifugal pump loses prime, which of the
following is most likely to result?
a. Pump sounds as though it is pumping gravel b. Pump is
no longer moving liquid
c. Check valve on the suction side of the pump slams
closed
d. RPM of motor increases to compensate
e. a, b, & c - Answers-B
A Rotating Biological Contactor (RBC) is -
a. Fixed film biological treatment process
b. Addition to most Activated Sludge Plants
c. New filter media aerobic digester
TEXAS WASTEWATER CLASS C TEST 2026/2027
EXAM QUESTIONS ACCURATE ACTUAL
EXAM||VERIFIED EXAM!!! FREQUENTLY TESTED
QUESTIONS WITH DETAILED ANSWERS |
GUARANTEED PASS | GRADED A+||NEWEST EXAM!!!
Which device may be used to determine the level of
sewage in a lift station?
a. Air bubbler tube
b. Parshall Flume
c. Altitude Valve
d. Air Actuated Valve
e. All the above - Answers-A
What is the most important role of aerobic bacteria in the
treatment of wastewater?
a. Enhance organic matter
b. Decompose organic matter
c. Introduce workers to dangerous diseases
d. Enhance oxygen production
e. Produces Odor and Offensive Smells - Answers-B
,2|Page
The hydraulic loading of a trickling filter may be
determined by -
a. BOD and depth of filter media
b. Organic loading and filter volume
c. Total pounds of BOD removed
d. Total pounds of suspended solids applied daily
e. Flow rate and filter area - Answers-E
Which of the following is typically used to dewater sludge?
a. Belt press
b. Drying beds
c. Solid bowl centrifuge
d. Gravity thickener
e. All the above - Answers-E
Which of the following are the most important to providing
adequate sewage treatment in a stabilization pond?
a. Protozoa, rotifers and turtles
b. Sunlight, algae, bacteria, and Time
c. Aeration, Sedimentation, and Chlorine Contact
d. Nitrification, Sedimentation, Recirculation, & Detention
,3|Page
e. Blowers, Diffusers, & Ultraviolet Disinfection - Answers-
B
Offensive and objectionable odors which sometimes occur
in trickling filters usually indicate that -
a. The filter should be backwashed
b. The flow is too great for the filter area
c. Chlorinator is not working properly & algae is growing
on the media
d. Septic conditions are present
e. All the above - Answers-D
Dissolved Oxygen (DO) in the aeration tank of an
activated sludge plant should be maintained at or about -
a. 1 to 2 mg/L
b. 2 to 3 mg/L
c. 2 to 4 mg/L
d. 4 to 6 mg/L
e. 0.5 to 0.75 mg/L - Answers-C
, 4|Page
Which of the following would contribute to infiltration in a
collection system?
a. Breaks in the main lines
b. High ground water levels
c. Heavy rains
d. Hydro jet cleaning plugged mains
e. a, b, & c - Answers-E
When a centrifugal pump loses prime, which of the
following is most likely to result?
a. Pump sounds as though it is pumping gravel b. Pump is
no longer moving liquid
c. Check valve on the suction side of the pump slams
closed
d. RPM of motor increases to compensate
e. a, b, & c - Answers-B
A Rotating Biological Contactor (RBC) is -
a. Fixed film biological treatment process
b. Addition to most Activated Sludge Plants
c. New filter media aerobic digester
