Class D Water Operator Exam A++ Graded Top Tier
Questions and Their Correctly Answered Questions
_______ is the final step in removing suspended matter and chlorine resistant microorganisms. -
CORRECT ANSWER ✔✔ -Filtration
____________ is buildup of oxidized iron, calcium carbonate, or other chemicals in mains. High
pressure water, pigs or swabs, and chemicals are methods of removing scale. - CORRECT
ANSWER ✔✔ -Tuberculation
_____________ is the process where ice and snow evaporate into the atmosphere without first
melting into a liquid form. - CORRECT ANSWER ✔✔ -Sublimation
1 psi = ________ ft of water column - CORRECT ANSWER ✔✔ -2.31
A common filter is the rapid sand filter, which filters ____ gpm/ft2 of filter media. - CORRECT
ANSWER ✔✔ -2
A cross connection is a physical connection between a public water system and:
- another supply of _________ quality
- any source that may contain _________
-any water treated to a __________ degree - CORRECT ANSWER ✔✔ -unknown or
questionable
contamination
lesser
,A safety program must start with support from the _________, then extend to all employees. -
CORRECT ANSWER ✔✔ -top official
A sand filter has _____ to ____ inches of porous material such as sand or anthracite coal, called
filter media. - CORRECT ANSWER ✔✔ -24" to 30"
A scale called the ________ measures odor. - CORRECT ANSWER ✔✔ -Threshold Odor
Number (TON)
A standpipe is considered ground storage unless it exceeds _____ft above the highest service
connection. - CORRECT ANSWER ✔✔ -80
A system's filtered water must be _______ Nephelometric Turbidity Units (NTU) or less in at
least 95% of the measurements taken each month, and no sample can exceed _____ NTU. -
CORRECT ANSWER ✔✔ -0.3
1
A tank resting on the ground that is greater in height than diameter is called a _________. -
CORRECT ANSWER ✔✔ -standpipe
A water system with ground storage is allowed pressure tank capacity of ______ gallons per
connection. - CORRECT ANSWER ✔✔ -20 gallons per connection
A water system without ground storage must have pressure tank capacity of _____ gallons per
connection. - CORRECT ANSWER ✔✔ -50 gallons per connection
According to OSHA, soil that has previously been disturbed is classified as soil type _________.
- CORRECT ANSWER ✔✔ -C
, According to OSHA, three criteria classify a _____________.
1) large enough and so configured that an employee may enter and do work;
2) has limited or restricted means of entry or exit;
3) is not designed for continuous occupancy. - CORRECT ANSWER ✔✔ -confined space
After the floc forms, the water flows into a sedimentation basin. A detention time of at least ____
hours is required to allow the floc to settle. - CORRECT ANSWER ✔✔ -6
All activities shall be restricted within _____ feet of a surface water treatment plant intake. -
CORRECT ANSWER ✔✔ -200
All community and non-transient, non-community water systems must not exceed a maximum
free chlorine or chloramine residual of ______ mg/L based on the running annual average of all
distribution samples. - CORRECT ANSWER ✔✔ -4 mg/L
All ground storage tanks must have an access opening at least _______ inch diameter. -
CORRECT ANSWER ✔✔ -30"
An exterior and interior inspection of all tanks must be conducted how often? How long must the
documented inspection results be kept? - CORRECT ANSWER ✔✔ -Yearly inspection required,
keep results 5 years
As the solids increase, there will be a loss of head pressure through the filter due to increased
friction. When this head loss is about ____ to _____ feet, the filter must be backwashed. -
CORRECT ANSWER ✔✔ -6-10 feet
Questions and Their Correctly Answered Questions
_______ is the final step in removing suspended matter and chlorine resistant microorganisms. -
CORRECT ANSWER ✔✔ -Filtration
____________ is buildup of oxidized iron, calcium carbonate, or other chemicals in mains. High
pressure water, pigs or swabs, and chemicals are methods of removing scale. - CORRECT
ANSWER ✔✔ -Tuberculation
_____________ is the process where ice and snow evaporate into the atmosphere without first
melting into a liquid form. - CORRECT ANSWER ✔✔ -Sublimation
1 psi = ________ ft of water column - CORRECT ANSWER ✔✔ -2.31
A common filter is the rapid sand filter, which filters ____ gpm/ft2 of filter media. - CORRECT
ANSWER ✔✔ -2
A cross connection is a physical connection between a public water system and:
- another supply of _________ quality
- any source that may contain _________
-any water treated to a __________ degree - CORRECT ANSWER ✔✔ -unknown or
questionable
contamination
lesser
,A safety program must start with support from the _________, then extend to all employees. -
CORRECT ANSWER ✔✔ -top official
A sand filter has _____ to ____ inches of porous material such as sand or anthracite coal, called
filter media. - CORRECT ANSWER ✔✔ -24" to 30"
A scale called the ________ measures odor. - CORRECT ANSWER ✔✔ -Threshold Odor
Number (TON)
A standpipe is considered ground storage unless it exceeds _____ft above the highest service
connection. - CORRECT ANSWER ✔✔ -80
A system's filtered water must be _______ Nephelometric Turbidity Units (NTU) or less in at
least 95% of the measurements taken each month, and no sample can exceed _____ NTU. -
CORRECT ANSWER ✔✔ -0.3
1
A tank resting on the ground that is greater in height than diameter is called a _________. -
CORRECT ANSWER ✔✔ -standpipe
A water system with ground storage is allowed pressure tank capacity of ______ gallons per
connection. - CORRECT ANSWER ✔✔ -20 gallons per connection
A water system without ground storage must have pressure tank capacity of _____ gallons per
connection. - CORRECT ANSWER ✔✔ -50 gallons per connection
According to OSHA, soil that has previously been disturbed is classified as soil type _________.
- CORRECT ANSWER ✔✔ -C
, According to OSHA, three criteria classify a _____________.
1) large enough and so configured that an employee may enter and do work;
2) has limited or restricted means of entry or exit;
3) is not designed for continuous occupancy. - CORRECT ANSWER ✔✔ -confined space
After the floc forms, the water flows into a sedimentation basin. A detention time of at least ____
hours is required to allow the floc to settle. - CORRECT ANSWER ✔✔ -6
All activities shall be restricted within _____ feet of a surface water treatment plant intake. -
CORRECT ANSWER ✔✔ -200
All community and non-transient, non-community water systems must not exceed a maximum
free chlorine or chloramine residual of ______ mg/L based on the running annual average of all
distribution samples. - CORRECT ANSWER ✔✔ -4 mg/L
All ground storage tanks must have an access opening at least _______ inch diameter. -
CORRECT ANSWER ✔✔ -30"
An exterior and interior inspection of all tanks must be conducted how often? How long must the
documented inspection results be kept? - CORRECT ANSWER ✔✔ -Yearly inspection required,
keep results 5 years
As the solids increase, there will be a loss of head pressure through the filter due to increased
friction. When this head loss is about ____ to _____ feet, the filter must be backwashed. -
CORRECT ANSWER ✔✔ -6-10 feet
