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Formula: MGD x 8.34 x mg/L = lbs - ANSWER-3.65 mg/L (rounding)
A chlorine cylinder valve is thought to be leaking. If ammonia vapor is passed near the
valve, the presence of a leak would be indicated by: - ANSWER-White smoke
A chlorine residual in water can be determined by using the reagent: - ANSWER-DPD -
diethyl-p-pheylenediamine
A disease that cannot be contracted by drinking contaminated water is: - ANSWER-
Malaria
A flow of 1.55 ft^3 per second is ___ gpm - ANSWER-696 gpm
A grab sample represents the quality of the water when? - ANSWER-Only when the
sample was taken
A hypochlorinator is used to feed ___ into a water supply - ANSWER-Hypochlorite
solution
A major cause of pump and motor shaft coupling wear is a: - ANSWER-Misalignment
between pumps and motor flanges
A non-permit confined space by OSHA standards means a confined space that: -
ANSWER-Does not contain or have the potential to contain any hazard capable of
causing death
A pH reading of 6.0 in raw water indicates the sample is what? - ANSWER-Acidic
A pH value of 7.0 is considered to be what? - ANSWER-Neutral
A pneumatic ejector lifts water from low points to higher levels. The device used to
achieve this is a(n)? - ANSWER-Air compressor
A pump may be damaged if it is started with the discharge valve closed, and the pump
is a(n): - ANSWER-Positive displacement pump
A sand filter will not remove: - ANSWER-Dissolved oxygen
A standpipe: - ANSWER-Has a diameter less than it's height
, A valve that joins a customer's service to the water main is called the ____ - ANSWER-
Corporation cock
A water storage tank must be disinfected with a dosage of 50 mg/L. The tank is 36 feet
in diameter and 20 feet high. The amount of 65% calcium hypochlorite needed is:
Formula: MGD x 8.34 x mg/L = lbs - ANSWER-97 lbs. (rounding)
A water treatment plant receives an average flow of 261 gallons per minute. What is the
daily flow of the plant? - ANSWER-0.38 MGD (rounded)
According to the average annual water budget for Texas, the majority of surface water
leaves the state by: - ANSWER-Evaporation and transpiration
According to the TCEQ, a public water system is defined as any water system that
provides piped water for human consumption to at least _(a)_ service connections on a
year-round basis or regularly serves _(b)_ individuals daily at least_(c)_ days out of the
year. - ANSWER-(a) 15; (b) 25; (c) 60
After installation or repair of a water line, it should be treated with: - ANSWER-50 mg/L
of chlorine for 24 hours
Alkalinity is a direct measure of water's capability to resists changes in: - ANSWER-pH
(acidity)
An altitude valve is used to: - ANSWER-Control the water elevation in an elevated
storage tank
An employee without a breathing apparatus is in a room where chlorine gas suddenly
begins leaking. What should the employee do first? - ANSWER-Keep mouth closed,
keep head as high as possible, and quickly walk out of the room, holding their breath if
possible
Baffles are used to prevent short-circuiting in: - ANSWER-Sedimentation basins
Before changing a gas chlorine cylinder in a room, the first step should be: - ANSWER-
Start the exhaust vent fan
Black stains on plumbing fixtures might be attributed to what? - ANSWER-Manganese
Calcium hypochlorite is formulated as a: - ANSWER-Powder
Calcium hypochlorite: - ANSWER-is 60%-70% chlorine
Carbon dioxide in water will do what to the pH? - ANSWER-Lower the pH