Water Treatment Plant Operator UPDATED
ACTUAL Exam Questions and CORRECT
Answers
What is used as a chemical coagulant? - CORRECT ANSWER Alum
The correct order of treatment in a surface water plant is... - CORRECT
ANSWER Coagulation, Flocculation, Sedimentation and Filtration
In determining the proper dosage of alum, the most useful test is the____________ test. -
CORRECT ANSWER Jar
If sludge is not continually removed from the sedimentation basin, its accumulation results in? -
CORRECT ANSWER Turbidity
The most widely used coagulant is.... - CORRECT ANSWER Aluminum sulfate
Optimum flocculation requires: - CORRECT ANSWER Gentle Agitation
Dissolved iron in excessive amounts results in consumer complaints about: - CORRECT
ANSWER Turbidity
The most important raw water constituent for a surface water plant is.... - CORRECT
ANSWER Turbidity
Turbidity in water is cause by the presence of..... - CORRECT ANSWER Suspended
materials
,The main purpose of the jar test is to determine the best: - CORRECT
ANSWER Coagulant dosage
The formation of chlorine ice affects chlorine feed rate. This can be prevented by: - CORRECT
ANSWER Decreasing the rate of chlorine withdrawal
The fusible metal plug on a chlorine cylinder is designed to open at what temperature range? -
CORRECT ANSWER 157F-162F
A lantern ring is a.... - CORRECT ANSWER spacer ring in a pump packing gland
When backwashing a filter, the backwash valve should be opened slowly to prevent.... -
CORRECT ANSWER Sand boils
Suction lift refers to the pressure difference between the center line of the pump.... - CORRECT
ANSWER down to the hydraulic grade line
The parameter used to describe the roughness of the pipe interiors is called? - CORRECT
ANSWER C factor
Prechlorination of raw water can lead to an interaction of chlorine with organic matter which can
form? - CORRECT ANSWER Trihalomethanes
What is the main purpose of the coagulation and flocculation process? - CORRECT
ANSWER To remove turbidity
What conditions most affect coagulation performance? - CORRECT ANSWER Velocity,
water temperature, detention time and coagulant dosage
What would be the best indicator that the filter should be backwashed? - CORRECT
ANSWER Filter effluent turbidity
, The most crucial element of effective filter performance is... - CORRECT
ANSWER proper backwashing
What is the chemical formula for calcium hypochlorite? - CORRECT
ANSWER Ca(OCI)2
A violation of the MCL for total trihalomethanes occurs when? - CORRECT
ANSWER The running average of quarterly samples during the previous 12 months
exceeds the MCL.
CT is defined as.... - CORRECT ANSWER The product of residual disinfectant
concentration and contact time of the disinfectant with the water.
What would the pH of water be that had the highest concentration of hypochlorous acid? -
CORRECT ANSWER pH of 10, optimum range is pH of 5
What is the solution used to regenerate a zeolite softening unit? - CORRECT
ANSWER Sodium chloride solution or NaCL
Langelier's index is used to determine - CORRECT ANSWER Corrosiveness
An effective chemical to raise pH is.... - CORRECT ANSWER Caustic Soda AKA
Sodium Hydroxide
Minerals that cause an increase in alkalinity are? - CORRECT ANSWER Calcium
Carbonate and Magnesium Bicarbonate
A problem related to ion exchange softeners is? - CORRECT ANSWER Increase in
sodium content
ACTUAL Exam Questions and CORRECT
Answers
What is used as a chemical coagulant? - CORRECT ANSWER Alum
The correct order of treatment in a surface water plant is... - CORRECT
ANSWER Coagulation, Flocculation, Sedimentation and Filtration
In determining the proper dosage of alum, the most useful test is the____________ test. -
CORRECT ANSWER Jar
If sludge is not continually removed from the sedimentation basin, its accumulation results in? -
CORRECT ANSWER Turbidity
The most widely used coagulant is.... - CORRECT ANSWER Aluminum sulfate
Optimum flocculation requires: - CORRECT ANSWER Gentle Agitation
Dissolved iron in excessive amounts results in consumer complaints about: - CORRECT
ANSWER Turbidity
The most important raw water constituent for a surface water plant is.... - CORRECT
ANSWER Turbidity
Turbidity in water is cause by the presence of..... - CORRECT ANSWER Suspended
materials
,The main purpose of the jar test is to determine the best: - CORRECT
ANSWER Coagulant dosage
The formation of chlorine ice affects chlorine feed rate. This can be prevented by: - CORRECT
ANSWER Decreasing the rate of chlorine withdrawal
The fusible metal plug on a chlorine cylinder is designed to open at what temperature range? -
CORRECT ANSWER 157F-162F
A lantern ring is a.... - CORRECT ANSWER spacer ring in a pump packing gland
When backwashing a filter, the backwash valve should be opened slowly to prevent.... -
CORRECT ANSWER Sand boils
Suction lift refers to the pressure difference between the center line of the pump.... - CORRECT
ANSWER down to the hydraulic grade line
The parameter used to describe the roughness of the pipe interiors is called? - CORRECT
ANSWER C factor
Prechlorination of raw water can lead to an interaction of chlorine with organic matter which can
form? - CORRECT ANSWER Trihalomethanes
What is the main purpose of the coagulation and flocculation process? - CORRECT
ANSWER To remove turbidity
What conditions most affect coagulation performance? - CORRECT ANSWER Velocity,
water temperature, detention time and coagulant dosage
What would be the best indicator that the filter should be backwashed? - CORRECT
ANSWER Filter effluent turbidity
, The most crucial element of effective filter performance is... - CORRECT
ANSWER proper backwashing
What is the chemical formula for calcium hypochlorite? - CORRECT
ANSWER Ca(OCI)2
A violation of the MCL for total trihalomethanes occurs when? - CORRECT
ANSWER The running average of quarterly samples during the previous 12 months
exceeds the MCL.
CT is defined as.... - CORRECT ANSWER The product of residual disinfectant
concentration and contact time of the disinfectant with the water.
What would the pH of water be that had the highest concentration of hypochlorous acid? -
CORRECT ANSWER pH of 10, optimum range is pH of 5
What is the solution used to regenerate a zeolite softening unit? - CORRECT
ANSWER Sodium chloride solution or NaCL
Langelier's index is used to determine - CORRECT ANSWER Corrosiveness
An effective chemical to raise pH is.... - CORRECT ANSWER Caustic Soda AKA
Sodium Hydroxide
Minerals that cause an increase in alkalinity are? - CORRECT ANSWER Calcium
Carbonate and Magnesium Bicarbonate
A problem related to ion exchange softeners is? - CORRECT ANSWER Increase in
sodium content
