Wastewater Operator Certification Exam And Study Guide Exam Latest 2025 Actual Exam| Complete Accurate Questions And Verified Answers (100% Correct Answers) Already Graded A+

WASTEWATER OPERATOR CERTIFICATION EXAM
AND STUDY GUIDE EXAM LATEST 2025 ACTUAL
EXAM| COMPLETE ACCURATE QUESTIONS AND
VERIFIED ANSWERS (100% CORRECT ANSWERS)
ALREADY GRADED A+

Wastewater sources & characteristics:
Which organism would most probably be associated with moderate sludge
age and effluent water quality - ANSWER - free-swimming ciliates


Wastewater sources & characteristics:
Which organism would most probably be associated with high suspended
solids and biochemical oxygen demand (BOD) - ANSWER - amoebas


Wastewater sources & characteristics:
High suspended solids and BOD are most probably associated with which
type of organisms? - ANSWER - flagellates


Wastewater sources & characteristics:
What organism would most likely enhance the penetration of oxygen into
the activated sludge - ANSWER - rotifers


Rocks/Screens/Comminutors & Grit Removal:
Chlorine gas has a specific gravity of - ANSWER - 2.5 specific gravity



pg. 1

,Rocks/Screens/Comminutors & Grit Removal:
Proper flow velocity through a grit channel is indicated when the grit being
removed contains
a. no organics
b. a little organic material
c. about half the volume as the grit being removed
d. about the same volume as the grit being removed - ANSWER - a little
organic material


Sedimentation and Flotation:
Surface loading and detention time is a clarifier are directly related to: -
ANSWER - flow through a clarifier


Sedimentation and Flotation:
What is the expected range for the removal of settleable solids from a
primary clarifier? - ANSWER - 95-99%


Sedimentation and Flotation:
What condition will occur if sludge is not pumped out of primary clarifiers at
regular intervals? - ANSWER - clarifier will become septic


Sedimentation and Flotation:
Secondary clarifiers are usually located after:
a. primary clarifier
b. an anaerobic digester
c. a biological process
d. reaeration - ANSWER - a biological process


pg. 2

,Disinfection:
Which chemical in the following list is the strongest disinfectant?
a. chlorine
b. hypochlorous acid
c. hypochlorite acid
d. hydrochloric acid - ANSWER - hypochlorous acid


Disinfection:
What is the recommended withdrawal of chlorine in pounds from a 100 or
150 lb. cylinder in a 24-hr period such that freezing does not occur? -
ANSWER - 40 lb.


Disinfection:
If there is a leak from a valve on a sulfur dioxide tank and the lead is found
using ammonia, what color will the vapor fumes be? - ANSWER - white


Disinfection:
What is the acceptable sulfur dioxide level in mg/L in wastewater plant
effluent? - ANSWER - 0.5 mg/L or less


Disinfection:
What is the ultimate measure of effective chlorination? - ANSWER -
bacteriological result


Solids removal from secondary effluent:
Which one of the following methods would not be used to feed DRY
chemicals?



pg. 3

, a. screw feeder
b. vibrating trough
c. rotating feeder
d. plunger feeder - ANSWER - plunger feeder


Solids removal from secondary effluent:
Which method would not be used to feed LIQUID chemicals?
a. screw feeder
b. vibrating trough
c. rotating feeder
d. plunger feeder - ANSWER - screw feeder


Solids removal from secondary effluent:
Which type of feeder would most likely feed clear solutions?
a. rotameter
b. decanter
c. orifice
d. positive displacement - ANSWER - rotameter


Solids removal from secondary effluent:
What type of feeder would always feed a gas? - ANSWER - direct feed


Solids removal from secondary effluent:
What is "the" major factor in predicting the performance of wastewater
clarifiers? - ANSWER - solids loading



pg. 4