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WATER DISTRIBUTION D2 CALIFORNIA EXAM LATEST 2026-2027
ACTUAL EXAM WITH COMPLETE QUESTIONS AND CORRECT
DETAILED ANSWERS (100% VERIFIED ANSWERS) |ALREADY
GRADED A+| ||PROFESSOR VERIFIED|| ||BRANDNEW!!!||
A competent person must inspect excavations and adjacent areas
for hazards - ANSWER-daily, prior to the start of work, and as
needed throughout the shift.
The component of a centrifugal pump sometimes installed on the
end of a suction pipe to hold the priming is known as a -
ANSWER-foot valve
The principal purpose of an altitude valve on an elevated tank is
to - ANSWER-control maximum filling level in distribution storage.
The term primacy means the - ANSWER-authority by the states to
supersede the USEPA drinking water regulations.
Reciprocating positive displacement pumps are also known as -
ANSWER-Piston pumps
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Modertely hard water will have a hardness range of ----- mg/L as -
ANSWER-61 to 120
A common method for removing hydrogen sulfide from water is -
ANSWER-aeration
The treatment process designed to kill pathogenic organisms is -
ANSWER-disinfection
Lead in drinking water can result in - ANSWER-impaired mental
functioning in children.
A disease that might be transferred to a new victim through water
is - ANSWER-typhoid
An average percentage range for unaccounted for water in a fully
metered system is - ANSWER-11 to 15%
A cross connection is defined as a connection between -
ANSWER-a potable water system and nonpotable water system.
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Backsiphonage is caused by - ANSWER-partial vacuum in the
line.
Five milligrams per litre equals ----- parts per million - ANSWER-
5.0
When the pumping rate is increased, the effect on the cone of
depression is to - ANSWER-lower the pumping level
Which chemical is most often used to disinfect public water
supplies? - ANSWER-chlorine or chlorine compounds.
The purpose of a surge tank is to - ANSWER-control water
hammer.
The presence of total coliforms in drinking water indicates -
ANSWER-THe potential presence of pathogens.
The term MCL means - ANSWER-maximum contaminant level.
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The primary origin of coliforms in water supplies is - ANSWER-
fecal contamination by warm blooded animals.
The primary source of trihalomethanes (THMs) in drinking water
is - ANSWER-the reaction of chlorine compounds and organic
matter.
An air- gap device is used to - ANSWER-prevent backflow of
nonpotable water into a drinking water supply.
The primary health risk associated with trihalomethanes (THMs)
is - ANSWER-cancer.
The purpose of the fusible plug on a chlorine tank is to -
ANSWER-Prevent the cylinder from exploding at high
temperatures
The primary health risk associated with synthetic organic
compounds (SOCs) is - ANSWER-Cancer
WATER DISTRIBUTION D2 CALIFORNIA EXAM LATEST 2026-2027
ACTUAL EXAM WITH COMPLETE QUESTIONS AND CORRECT
DETAILED ANSWERS (100% VERIFIED ANSWERS) |ALREADY
GRADED A+| ||PROFESSOR VERIFIED|| ||BRANDNEW!!!||
A competent person must inspect excavations and adjacent areas
for hazards - ANSWER-daily, prior to the start of work, and as
needed throughout the shift.
The component of a centrifugal pump sometimes installed on the
end of a suction pipe to hold the priming is known as a -
ANSWER-foot valve
The principal purpose of an altitude valve on an elevated tank is
to - ANSWER-control maximum filling level in distribution storage.
The term primacy means the - ANSWER-authority by the states to
supersede the USEPA drinking water regulations.
Reciprocating positive displacement pumps are also known as -
ANSWER-Piston pumps
,2|Page
Modertely hard water will have a hardness range of ----- mg/L as -
ANSWER-61 to 120
A common method for removing hydrogen sulfide from water is -
ANSWER-aeration
The treatment process designed to kill pathogenic organisms is -
ANSWER-disinfection
Lead in drinking water can result in - ANSWER-impaired mental
functioning in children.
A disease that might be transferred to a new victim through water
is - ANSWER-typhoid
An average percentage range for unaccounted for water in a fully
metered system is - ANSWER-11 to 15%
A cross connection is defined as a connection between -
ANSWER-a potable water system and nonpotable water system.
,3|Page
Backsiphonage is caused by - ANSWER-partial vacuum in the
line.
Five milligrams per litre equals ----- parts per million - ANSWER-
5.0
When the pumping rate is increased, the effect on the cone of
depression is to - ANSWER-lower the pumping level
Which chemical is most often used to disinfect public water
supplies? - ANSWER-chlorine or chlorine compounds.
The purpose of a surge tank is to - ANSWER-control water
hammer.
The presence of total coliforms in drinking water indicates -
ANSWER-THe potential presence of pathogens.
The term MCL means - ANSWER-maximum contaminant level.
, 4|Page
The primary origin of coliforms in water supplies is - ANSWER-
fecal contamination by warm blooded animals.
The primary source of trihalomethanes (THMs) in drinking water
is - ANSWER-the reaction of chlorine compounds and organic
matter.
An air- gap device is used to - ANSWER-prevent backflow of
nonpotable water into a drinking water supply.
The primary health risk associated with trihalomethanes (THMs)
is - ANSWER-cancer.
The purpose of the fusible plug on a chlorine tank is to -
ANSWER-Prevent the cylinder from exploding at high
temperatures
The primary health risk associated with synthetic organic
compounds (SOCs) is - ANSWER-Cancer
