ADEQ Wastewater Treatment 1 Exam
Questions and Answers Updated 2026
Reason to use perchlorinating at a wastewater treatment facility?
a. Decrease TSS load
b. Begin sterilization process
c. Inhibit growth of odor-producing bacteria
d. Promote settling of inorganic materials -Correct Answer ✔-Inhibit growth of
odor-producing bacteria
The electrical current draw rate is measured in?
a. Volts
b. Amps
c. Ohms
d. Watts -Correct Answer ✔-Amps
All piping connections in a chlorine gas system should be checked for leaks by:
a. Pressure gauge
b. Ammonia vapors near connections
c. Misting water
d. Looking for signs of corrosion -Correct Answer ✔-Ammonia vapors near
connections
Improper use or lack of backflow preventers may create:
a. Increased water pressure
b. Low water pressure
c. Contamination
d. Fluctuating water pressure -Correct Answer ✔-Contamination
Tool to check bearings on an electrical motor?
a. Tachometer
b. Stethoscope
c. Vibration meter
,d. Oscilloscope -Correct Answer ✔-Vibration meter
Longest life seal under normal conditions?
a. Mechanical seal
b. Water seal
c. Packing seal
d. Gland seal -Correct Answer ✔-Mechanical seal
pH test with an electrode?
a. Raise temperature to 40°C
b. Lower temperature to 2°C
c. Dechlorinate
d. Maintain constant stirring rate -Correct Answer ✔-Maintain constant stirring
rate
Dry chemical feeder: 2.65 lbs in 5 minutes. What is the rate?
a. 13 lbs/day
b. 763 lbs/day
c. 3883 lbs/day
d. 48,203 lbs/day -Correct Answer ✔-763 lbs/day
Changing oil every 1000 hours is what type of maintenance?
a. Preventative
b. Reactive
c. Run-to-failure
d. Conditional -Correct Answer ✔-Preventative
Sludge sample test for MLSS?
a. Remix
b. Filter
c. Allow to stand
d. Acidity -Correct Answer ✔-Filter
Minimum DO level test time on a facultative lagoon?
, a. 5 am
b. 11 am
c. 5 pm
d. 11 pm -Correct Answer ✔-5 am
Which form of solids is MOST difficult to remove in a gravity treatment process?
a. Coagulant
b. Precipitated
c. Colloids -Correct Answer ✔-Colloids
A greasy scummy layer of deep tan or dark brown foam on an aerator tank is
MOST likely due to:
a. Old mixed liquor solids
b. Young mixed liquor solids
c. Plant received toxic load
d. Brown color indicates everything is dying -Correct Answer ✔-Old mixed liquor
solids
MOST commonly used to determine stabilization of solids in an aerobic digester?
a. Methane gas production
b. Volatile acid alkalinity ratio
c. Specific oxygen uptake rate
d. VSI -Correct Answer ✔-Specific oxygen uptake rate
Primary objective of the industrial pretreatment program?
a. Ensure industrial users receive adequate water supply
b. Attract industrial users to the community
c. Eliminate discharge from industrial users
d. Regulate discharge from industrial users -Correct Answer ✔-Regulate discharge
from industrial users
Raw wastewater CBOD concentration of 450 ppm, most likely due to:
a. High organic load
b. Low organic load
Questions and Answers Updated 2026
Reason to use perchlorinating at a wastewater treatment facility?
a. Decrease TSS load
b. Begin sterilization process
c. Inhibit growth of odor-producing bacteria
d. Promote settling of inorganic materials -Correct Answer ✔-Inhibit growth of
odor-producing bacteria
The electrical current draw rate is measured in?
a. Volts
b. Amps
c. Ohms
d. Watts -Correct Answer ✔-Amps
All piping connections in a chlorine gas system should be checked for leaks by:
a. Pressure gauge
b. Ammonia vapors near connections
c. Misting water
d. Looking for signs of corrosion -Correct Answer ✔-Ammonia vapors near
connections
Improper use or lack of backflow preventers may create:
a. Increased water pressure
b. Low water pressure
c. Contamination
d. Fluctuating water pressure -Correct Answer ✔-Contamination
Tool to check bearings on an electrical motor?
a. Tachometer
b. Stethoscope
c. Vibration meter
,d. Oscilloscope -Correct Answer ✔-Vibration meter
Longest life seal under normal conditions?
a. Mechanical seal
b. Water seal
c. Packing seal
d. Gland seal -Correct Answer ✔-Mechanical seal
pH test with an electrode?
a. Raise temperature to 40°C
b. Lower temperature to 2°C
c. Dechlorinate
d. Maintain constant stirring rate -Correct Answer ✔-Maintain constant stirring
rate
Dry chemical feeder: 2.65 lbs in 5 minutes. What is the rate?
a. 13 lbs/day
b. 763 lbs/day
c. 3883 lbs/day
d. 48,203 lbs/day -Correct Answer ✔-763 lbs/day
Changing oil every 1000 hours is what type of maintenance?
a. Preventative
b. Reactive
c. Run-to-failure
d. Conditional -Correct Answer ✔-Preventative
Sludge sample test for MLSS?
a. Remix
b. Filter
c. Allow to stand
d. Acidity -Correct Answer ✔-Filter
Minimum DO level test time on a facultative lagoon?
, a. 5 am
b. 11 am
c. 5 pm
d. 11 pm -Correct Answer ✔-5 am
Which form of solids is MOST difficult to remove in a gravity treatment process?
a. Coagulant
b. Precipitated
c. Colloids -Correct Answer ✔-Colloids
A greasy scummy layer of deep tan or dark brown foam on an aerator tank is
MOST likely due to:
a. Old mixed liquor solids
b. Young mixed liquor solids
c. Plant received toxic load
d. Brown color indicates everything is dying -Correct Answer ✔-Old mixed liquor
solids
MOST commonly used to determine stabilization of solids in an aerobic digester?
a. Methane gas production
b. Volatile acid alkalinity ratio
c. Specific oxygen uptake rate
d. VSI -Correct Answer ✔-Specific oxygen uptake rate
Primary objective of the industrial pretreatment program?
a. Ensure industrial users receive adequate water supply
b. Attract industrial users to the community
c. Eliminate discharge from industrial users
d. Regulate discharge from industrial users -Correct Answer ✔-Regulate discharge
from industrial users
Raw wastewater CBOD concentration of 450 ppm, most likely due to:
a. High organic load
b. Low organic load
