AWWA Operator Certification Study Guide 4th
ED. - Water Treatment Test 3 questions and
answers with solutions 2025/2026
The concentration of chlorine that is immediately dangerous to health
and life (IDHL) is _____ parts per million. - ANSWER 30ppm
The common rate of operation of a rapid sand filter is considered to be
_____ gallons per square foot per minute. - ANSWER 2 to 6
An operator inspects valves to determine that they are holding properly
by... - ANSWER a pressure test
Trihalomethane (THM) precursors are _____ compounds. - ANSWER
natural organic
How many gallons does 1,000 feet of 15-inch diameter pipe contain? -
ANSWER 9,175
Chemicals that may be used for corrosion control in water treatment
are; - ANSWER phosphate compounds, sodium bicarbonate, calcium
hydroxide, and sodium carbonate
, A 2-foot wide rectangular channel is flowing 18 inches deep with an
average velocity of 5 feet per second. The rate of flow is approximately
_____ cubic feet per second. - ANSWER 15
A dosage of 17.1 mg/L coagulant applied to water in a plant of 1,000
gallons per minute capacity and operating over a 10-hour period will
require a total of _____ pounds of coagulant. - ANSWER 85.5
Three most commonly used coagulants in water treatment are; -
ANSWER aluminum sulfate, ferric chloride, and ferrous sulfate
An employer must have a Process Safety Plan if the plant has the
capability of storing at least _____ pounds of chlorine. - ANSWER 1,500
A high heterotrophic plate count (HPC) in water samples; - ANSWER can
mask detection of coliforms
How many pounds of polymer are required to make up 750 gallons of
0.25 percent polymer solution? - ANSWER 15.6 (pounds per gallon
formula)
Potassium permanganate is applied in water treatment for... - ANSWER a
regenerant and oxidant
In order for a chemical to function satisfactorily as a coagulant, it must...
- ANSWER react with the alkalinity in the water causing floc formations
ED. - Water Treatment Test 3 questions and
answers with solutions 2025/2026
The concentration of chlorine that is immediately dangerous to health
and life (IDHL) is _____ parts per million. - ANSWER 30ppm
The common rate of operation of a rapid sand filter is considered to be
_____ gallons per square foot per minute. - ANSWER 2 to 6
An operator inspects valves to determine that they are holding properly
by... - ANSWER a pressure test
Trihalomethane (THM) precursors are _____ compounds. - ANSWER
natural organic
How many gallons does 1,000 feet of 15-inch diameter pipe contain? -
ANSWER 9,175
Chemicals that may be used for corrosion control in water treatment
are; - ANSWER phosphate compounds, sodium bicarbonate, calcium
hydroxide, and sodium carbonate
, A 2-foot wide rectangular channel is flowing 18 inches deep with an
average velocity of 5 feet per second. The rate of flow is approximately
_____ cubic feet per second. - ANSWER 15
A dosage of 17.1 mg/L coagulant applied to water in a plant of 1,000
gallons per minute capacity and operating over a 10-hour period will
require a total of _____ pounds of coagulant. - ANSWER 85.5
Three most commonly used coagulants in water treatment are; -
ANSWER aluminum sulfate, ferric chloride, and ferrous sulfate
An employer must have a Process Safety Plan if the plant has the
capability of storing at least _____ pounds of chlorine. - ANSWER 1,500
A high heterotrophic plate count (HPC) in water samples; - ANSWER can
mask detection of coliforms
How many pounds of polymer are required to make up 750 gallons of
0.25 percent polymer solution? - ANSWER 15.6 (pounds per gallon
formula)
Potassium permanganate is applied in water treatment for... - ANSWER a
regenerant and oxidant
In order for a chemical to function satisfactorily as a coagulant, it must...
- ANSWER react with the alkalinity in the water causing floc formations
