Class "C" Water Exam Questions With Complete Solutions
.433 lbs Correct Answers One foot of water inside a storage
vessel will raise a pressure gauge at the bottom of the vessel by-
0-14 Correct Answers The pH of water is expressed by a scale
of numbers ranging from-
0.2 mg/L free chlorine residual
0.5 mg/L chloramine residual for a surface water supply
0.8 mg/L chloramine residual when using chloramine treatment
0.5 mg/L free chlorine residual for a groundwater supply Correct
Answers Which of the following is an acceptable disinfection
residual at the far reaches of the distribution system-
0.6 gpm Correct Answers TCEQ requires community water
systems to have a minimum production capacity of ___ per
connection at peak demand.
0.8 mg/L Correct Answers The current MCL for
Trihalomethanes (THM's) is-
1 1/2 times as great as the normal operating pressure Correct
Answers When pressure testing a water main, the test pressure
should be-
1 year Correct Answers Chemical testing of surface water
sources is required every-
,1/4 Correct Answers A rule of thumb for sludge blanket
thickness in solids contact, sludge blanket, and upflow clarifier
is ___the sidewall depth.
10.0 mg/L Correct Answers The primary MCL for nitrate in
drinking water is-
100/150/200/250 Correct Answers The four common classes of
working pressure in water main pipes are-
1000 ft Correct Answers A raw water intake structure may not
be constructed within _____ feet of a boat ramp, dock, or marina
12 inches Correct Answers Trenches for laying 6 inch and
larger pipe must be at least 18 inches wide and or ___ inches
wider than the pipe diameter.
130 gallons Correct Answers When designing systems
engineers use a rule of thumb of ___ gallons per person per day
when more accurate data not available.
15 % Correct Answers Unaccounted for water loss should be
less than __ % of water production.
150 feet Correct Answers Underground fuel tanks and septic
drainage fields must be at least ___ feet from a public well.
19.5 Correct Answers Any atmosphere that is less than ___ %
oxygen should not be entered without an approved self-
contained breathing apparatus.
, 2 operators with "C" license Correct Answers A groundwater
system that serves in excess of 1,000 connections must have at
least ___ operator(s) with ___ license to meet minimum state
requirements for public water systems.
20.9 Correct Answers The normal oxygen content of the
atmosphere is ___ %
24 hours Correct Answers If and when a health hazard
contamination event occurs in a public water system, the
operator must contact the state regulatory authority within ___
hours by telephone.
24 hours Correct Answers Repairing water main leaks should
be repaired within ___.
24 to 30 inches Correct Answers The top of backwash troughs
should be ___ inches above the top of the filter media.
24 to 36 inches Correct Answers The top of a pipe in a trench
must be at least ___ from the top of the ground.
250 Correct Answers A Texas Class D Certified Operator can
operate a public water system up to ___ connections.
2500 connections Correct Answers Pressure Vessels (tanks) are
not recommended for systems over ___ connections.
3 feet above and 25 feet laterally Correct Answers In an
excavation if a ladder is used as a means of exit, it must extend
.433 lbs Correct Answers One foot of water inside a storage
vessel will raise a pressure gauge at the bottom of the vessel by-
0-14 Correct Answers The pH of water is expressed by a scale
of numbers ranging from-
0.2 mg/L free chlorine residual
0.5 mg/L chloramine residual for a surface water supply
0.8 mg/L chloramine residual when using chloramine treatment
0.5 mg/L free chlorine residual for a groundwater supply Correct
Answers Which of the following is an acceptable disinfection
residual at the far reaches of the distribution system-
0.6 gpm Correct Answers TCEQ requires community water
systems to have a minimum production capacity of ___ per
connection at peak demand.
0.8 mg/L Correct Answers The current MCL for
Trihalomethanes (THM's) is-
1 1/2 times as great as the normal operating pressure Correct
Answers When pressure testing a water main, the test pressure
should be-
1 year Correct Answers Chemical testing of surface water
sources is required every-
,1/4 Correct Answers A rule of thumb for sludge blanket
thickness in solids contact, sludge blanket, and upflow clarifier
is ___the sidewall depth.
10.0 mg/L Correct Answers The primary MCL for nitrate in
drinking water is-
100/150/200/250 Correct Answers The four common classes of
working pressure in water main pipes are-
1000 ft Correct Answers A raw water intake structure may not
be constructed within _____ feet of a boat ramp, dock, or marina
12 inches Correct Answers Trenches for laying 6 inch and
larger pipe must be at least 18 inches wide and or ___ inches
wider than the pipe diameter.
130 gallons Correct Answers When designing systems
engineers use a rule of thumb of ___ gallons per person per day
when more accurate data not available.
15 % Correct Answers Unaccounted for water loss should be
less than __ % of water production.
150 feet Correct Answers Underground fuel tanks and septic
drainage fields must be at least ___ feet from a public well.
19.5 Correct Answers Any atmosphere that is less than ___ %
oxygen should not be entered without an approved self-
contained breathing apparatus.
, 2 operators with "C" license Correct Answers A groundwater
system that serves in excess of 1,000 connections must have at
least ___ operator(s) with ___ license to meet minimum state
requirements for public water systems.
20.9 Correct Answers The normal oxygen content of the
atmosphere is ___ %
24 hours Correct Answers If and when a health hazard
contamination event occurs in a public water system, the
operator must contact the state regulatory authority within ___
hours by telephone.
24 hours Correct Answers Repairing water main leaks should
be repaired within ___.
24 to 30 inches Correct Answers The top of backwash troughs
should be ___ inches above the top of the filter media.
24 to 36 inches Correct Answers The top of a pipe in a trench
must be at least ___ from the top of the ground.
250 Correct Answers A Texas Class D Certified Operator can
operate a public water system up to ___ connections.
2500 connections Correct Answers Pressure Vessels (tanks) are
not recommended for systems over ___ connections.
3 feet above and 25 feet laterally Correct Answers In an
excavation if a ladder is used as a means of exit, it must extend
