Wastewater Operator Class C Exam 2025: Practice Test & Study Guide

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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.

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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?

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.....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