DRINKING WATER OPERATOR
CERTIFICATION LIMITED TREATMENT
(D-LEVEL) PRACTICE EXAM
QUESTIONS AND ANSWERS
2000 feet - Answer-what is the minimum isolation distance of municipal well from a
major source of contamination
a landfill - Answer-which of the following is considered a major source of
contamination
78.57 ppm - Answer-the pump in your main well house has been replaced. the well
driller dumps 11 lbs of calcium hypochlorite down the well for disinfection. what is the
initial dosage of chlorine? assume calcium hypochlorite is 65% available chlorine.
well diameter is 18 in, well epth is 975 ft and the static water level is 150 ft below the
top of the casing.
35 celsius +_ 0.5 - Answer-what is the proper incubation temperature when using an
approved bacteriological testing method for bacteriological samples in drinking water
Corrosion - Answer-natural process that converts a refined metal into more
chemically stable oxide - occurs when most or all of the atoms on the same metal
surface are oxidizing damaging the entire surface
Calcium carbonate - Answer-appears as white odorless powder or colorless crystals.
practically insoluble in water. occurs extensive in rocks world-wide
cross connections - Answer-a connection or arrangement of piping or appurtenances
through which a backflow could occur
direct cross connection - Answer-a connection subject to back pressure and back
siphonage - permanent connection
indirect cross connection - Answer-Subject to backsiphonage only - may not be
permanent
disinfection - Answer-The process of destroying pathogens - chlorine is primarily
used
total chlorine - Answer-The total concentration in water, including the combined
chlorine (such as inorganic and organic chloramines) and the free available chlorine.
free chlorine - Answer-is not chemically bound to other substances.
contingency plan - Answer-a plan that outlines alternative courses of action that may
be taken if an organization's other plans are disrupted or become ineffective
CERTIFICATION LIMITED TREATMENT
(D-LEVEL) PRACTICE EXAM
QUESTIONS AND ANSWERS
2000 feet - Answer-what is the minimum isolation distance of municipal well from a
major source of contamination
a landfill - Answer-which of the following is considered a major source of
contamination
78.57 ppm - Answer-the pump in your main well house has been replaced. the well
driller dumps 11 lbs of calcium hypochlorite down the well for disinfection. what is the
initial dosage of chlorine? assume calcium hypochlorite is 65% available chlorine.
well diameter is 18 in, well epth is 975 ft and the static water level is 150 ft below the
top of the casing.
35 celsius +_ 0.5 - Answer-what is the proper incubation temperature when using an
approved bacteriological testing method for bacteriological samples in drinking water
Corrosion - Answer-natural process that converts a refined metal into more
chemically stable oxide - occurs when most or all of the atoms on the same metal
surface are oxidizing damaging the entire surface
Calcium carbonate - Answer-appears as white odorless powder or colorless crystals.
practically insoluble in water. occurs extensive in rocks world-wide
cross connections - Answer-a connection or arrangement of piping or appurtenances
through which a backflow could occur
direct cross connection - Answer-a connection subject to back pressure and back
siphonage - permanent connection
indirect cross connection - Answer-Subject to backsiphonage only - may not be
permanent
disinfection - Answer-The process of destroying pathogens - chlorine is primarily
used
total chlorine - Answer-The total concentration in water, including the combined
chlorine (such as inorganic and organic chloramines) and the free available chlorine.
free chlorine - Answer-is not chemically bound to other substances.
contingency plan - Answer-a plan that outlines alternative courses of action that may
be taken if an organization's other plans are disrupted or become ineffective
