Page 1 of 25
WASTEWATER OPERATOR CLASS C EXAM AND
PRACTICE EXAM NEWEST 2025 TEST BANK|
COMPLETE 400 REAL EXAM QUESTIONS AND
CORRECT VERIFIED ANSWERS/ GRADED A+|
WASTEWATER OPERATOR CLASS C TEST PREP 2025
(MOST RECENT!!)
Bio-monitoring involves the use of aquatic life to test the toxicity
of a wastewater treatment plant effluent. .....ANSWER..... TRUE
The definition of an oxygen-deficient atmosphere is one that
contains less than, what percentage of oxygen? .....ANSWER.....
19.5
1.) What is the function of a grit auger? .....ANSWER..... To
Separate Organic from Inorganics
2.) Running a 30 min settling test is the best indication of what?
.....ANSWER..... What is taking place in the Clarifier.
,Page 2 of 25
3.) How many inches do you pour a sludge drying bed?
.....ANSWER..... 8 to 12
4.) Why do you draw sludge into the drying bed at a slow rate?
.....ANSWER..... To promote drying of the sludge.
5.) In the F/M ratio what does the food stand for?
.....ANSWER..... Organics
6.) What can chlorine be used for in a trickiling filter?
.....ANSWER..... Reduce Ponding
7.) One part of liquid chlorine equals how much of Gas?
.....ANSWER..... 450
8.) What is the purpose of a pretreatment program?
.....ANSWER..... To cut cost and help with plant efficiency
9.) In a composite sample there was a Cl2 sample ran and there
was no residual present, what does that say about the sample?
, Page 3 of 25
.....ANSWER..... Inaccurate, Cl2 test is within 15 min, not 24 hours
later
10.) In order to be a good communicator, what else do you need
to be? .....ANSWER..... Listener
11.) During Nitrification, which organisms use ______ for food?
.....ANSWER..... Nitrates
In an Activated Sludge Treatment Process what is the most
predominant organism? .....ANSWER..... Ciliates and rotifers with
few flagellates.
The Detention Time in a Contact Stabilization plant is _____ than
other extended aeration plants. .....ANSWER..... Longer
14.) Other than disinfection chlorination can be used for what?
.....ANSWER..... Odor Control, Foaming, Reduce Algae Growth
15.) A leaking chlorine cylinder will do what? .....ANSWER.....
Have a frosty coated outside
WASTEWATER OPERATOR CLASS C EXAM AND
PRACTICE EXAM NEWEST 2025 TEST BANK|
COMPLETE 400 REAL EXAM QUESTIONS AND
CORRECT VERIFIED ANSWERS/ GRADED A+|
WASTEWATER OPERATOR CLASS C TEST PREP 2025
(MOST RECENT!!)
Bio-monitoring involves the use of aquatic life to test the toxicity
of a wastewater treatment plant effluent. .....ANSWER..... TRUE
The definition of an oxygen-deficient atmosphere is one that
contains less than, what percentage of oxygen? .....ANSWER.....
19.5
1.) What is the function of a grit auger? .....ANSWER..... To
Separate Organic from Inorganics
2.) Running a 30 min settling test is the best indication of what?
.....ANSWER..... What is taking place in the Clarifier.
,Page 2 of 25
3.) How many inches do you pour a sludge drying bed?
.....ANSWER..... 8 to 12
4.) Why do you draw sludge into the drying bed at a slow rate?
.....ANSWER..... To promote drying of the sludge.
5.) In the F/M ratio what does the food stand for?
.....ANSWER..... Organics
6.) What can chlorine be used for in a trickiling filter?
.....ANSWER..... Reduce Ponding
7.) One part of liquid chlorine equals how much of Gas?
.....ANSWER..... 450
8.) What is the purpose of a pretreatment program?
.....ANSWER..... To cut cost and help with plant efficiency
9.) In a composite sample there was a Cl2 sample ran and there
was no residual present, what does that say about the sample?
, Page 3 of 25
.....ANSWER..... Inaccurate, Cl2 test is within 15 min, not 24 hours
later
10.) In order to be a good communicator, what else do you need
to be? .....ANSWER..... Listener
11.) During Nitrification, which organisms use ______ for food?
.....ANSWER..... Nitrates
In an Activated Sludge Treatment Process what is the most
predominant organism? .....ANSWER..... Ciliates and rotifers with
few flagellates.
The Detention Time in a Contact Stabilization plant is _____ than
other extended aeration plants. .....ANSWER..... Longer
14.) Other than disinfection chlorination can be used for what?
.....ANSWER..... Odor Control, Foaming, Reduce Algae Growth
15.) A leaking chlorine cylinder will do what? .....ANSWER.....
Have a frosty coated outside
