TEXAS CLASS D WATER
DISTRIBUTION EXAM STUDY GUIDE
QUESTIONS AND ANSWERS
A physical connection between a potable water supply and a house well would be -
Answer-A cross connection
Excessive nitrates in drinking water can cause a condition that affects infants under
the age of 6 months the condition is called - Answer-Blue Baby
A public water system is required to take samples of water for bacteriological
analysis. The organism that is used as an indicator is called - Answer-Coliform
Chlorine dosage is demand plus desired _______________ - Answer-Residual
A storage vessel that is the same diameter from the ground to the top and is more
that 20 feet but less that 85 feet tall is called - Answer-Stand Pipe
A water tank uses compressed air over water to provide pressure is called a -
Answer-Hydro pneumatic tank
According to the lead and copper rule pipe and fitting may not contain more than
_____________ lead or solder and Flux may not contain more than 0.2% lead -
Answer-8.0%
When testing for chlorine residual DPD is used as an indicator. When DPD is added
to water containing chlorine, what color does the sample turn? - Answer-Red
The most common valve used for isolating a water leak is the _________________
valve - Answer-Gate Valve
In the distribution system when a valve or fire hydrant is opened or closed too fast it
could result in a - Answer-Water hammer
The most commonly used pump in the distribution system is - Answer-Centrifugal
A Texas Class D Certified operator can Operate a public water system up to ______
connections - Answer-250
All state of Texas operator licenses after issuance are good for ________ years -
Answer-3
Waterline should be installed no closer than _______ feet to any sewer lines -
Answer-9
Calcium hypochlorite (HTH) is used as an disinfectant in small systems what
percentage of chlorine is typical? - Answer-65% - 75%
, Flushing dead end mains - what is the minimum Flushing requirements per TCEQ? -
Answer-Once a month
The process of adding enough chlorine to a water supply to complete all reaction
with reducing compounds, ammonia and organic materials so that some free
chlorine is left is called - Answer-Breakpoint chlorination
Which of the following is a required step in collecting a routine distribution sample for
bacteriological testing? - Answer-Use an approved, sterile sample container
Potable water means that the water is
A. Maintained at adequate pressure
B. Pathogen free
C. Contains a chlorine residual
D. All of the above
E. B & C only - Answer-All of the above
Before a new or repaired water line is placed into service, it must be properly
disinfected by providing a chlorine dosage of __________________ and proper
detention time - Answer-50 mg/L
Should a public water supply systems distribution system drop below 20 psi, what is
required of the operator?
A. Nothing 20 psi is simply a goal
B. Immediately correct the problem or cause of low pressure
C. Notify the mayor and city council
D. Notify the Regional TCEQ office and issue a "Boil Water Notice"
E. Both B and D - Answer-Both B and D
In a groundwater system if the operator knows the " standing" water level in the well
when the pump is off and they know the water level in the well during "pumping",
they can determine the ________________ of the well. - Answer-Drawdown
TCEQ requires community water systems to have a minimum production capacity of
_________ per connection at peak demand - Answer-.06 gpm
The mesh size is an important feature of a well screen because properly sized
openings should - Answer-Reduce the amount of sand pumped
Which of the following is an acceptable disinfection residual at the far reaches of the
distribution system?
A. 0.2 mg/L free residual
B. 0.5 mg/L chloramines residual for a surface water supply
C. 0.8 mg/L chloramines residual when using chloramines treatment
D. 0.5 mg/L free chlorine residual for a ground water supply
E. All of the above - Answer-All of the above
DISTRIBUTION EXAM STUDY GUIDE
QUESTIONS AND ANSWERS
A physical connection between a potable water supply and a house well would be -
Answer-A cross connection
Excessive nitrates in drinking water can cause a condition that affects infants under
the age of 6 months the condition is called - Answer-Blue Baby
A public water system is required to take samples of water for bacteriological
analysis. The organism that is used as an indicator is called - Answer-Coliform
Chlorine dosage is demand plus desired _______________ - Answer-Residual
A storage vessel that is the same diameter from the ground to the top and is more
that 20 feet but less that 85 feet tall is called - Answer-Stand Pipe
A water tank uses compressed air over water to provide pressure is called a -
Answer-Hydro pneumatic tank
According to the lead and copper rule pipe and fitting may not contain more than
_____________ lead or solder and Flux may not contain more than 0.2% lead -
Answer-8.0%
When testing for chlorine residual DPD is used as an indicator. When DPD is added
to water containing chlorine, what color does the sample turn? - Answer-Red
The most common valve used for isolating a water leak is the _________________
valve - Answer-Gate Valve
In the distribution system when a valve or fire hydrant is opened or closed too fast it
could result in a - Answer-Water hammer
The most commonly used pump in the distribution system is - Answer-Centrifugal
A Texas Class D Certified operator can Operate a public water system up to ______
connections - Answer-250
All state of Texas operator licenses after issuance are good for ________ years -
Answer-3
Waterline should be installed no closer than _______ feet to any sewer lines -
Answer-9
Calcium hypochlorite (HTH) is used as an disinfectant in small systems what
percentage of chlorine is typical? - Answer-65% - 75%
, Flushing dead end mains - what is the minimum Flushing requirements per TCEQ? -
Answer-Once a month
The process of adding enough chlorine to a water supply to complete all reaction
with reducing compounds, ammonia and organic materials so that some free
chlorine is left is called - Answer-Breakpoint chlorination
Which of the following is a required step in collecting a routine distribution sample for
bacteriological testing? - Answer-Use an approved, sterile sample container
Potable water means that the water is
A. Maintained at adequate pressure
B. Pathogen free
C. Contains a chlorine residual
D. All of the above
E. B & C only - Answer-All of the above
Before a new or repaired water line is placed into service, it must be properly
disinfected by providing a chlorine dosage of __________________ and proper
detention time - Answer-50 mg/L
Should a public water supply systems distribution system drop below 20 psi, what is
required of the operator?
A. Nothing 20 psi is simply a goal
B. Immediately correct the problem or cause of low pressure
C. Notify the mayor and city council
D. Notify the Regional TCEQ office and issue a "Boil Water Notice"
E. Both B and D - Answer-Both B and D
In a groundwater system if the operator knows the " standing" water level in the well
when the pump is off and they know the water level in the well during "pumping",
they can determine the ________________ of the well. - Answer-Drawdown
TCEQ requires community water systems to have a minimum production capacity of
_________ per connection at peak demand - Answer-.06 gpm
The mesh size is an important feature of a well screen because properly sized
openings should - Answer-Reduce the amount of sand pumped
Which of the following is an acceptable disinfection residual at the far reaches of the
distribution system?
A. 0.2 mg/L free residual
B. 0.5 mg/L chloramines residual for a surface water supply
C. 0.8 mg/L chloramines residual when using chloramines treatment
D. 0.5 mg/L free chlorine residual for a ground water supply
E. All of the above - Answer-All of the above
