Water Treatment Quiz 3 Questions with
Latest Update
The best pH level for coagulation usually falls in the range of - Answer-5-7
Which, surface water or groundwater, usually contains a higher level of pathogens -
Answer-surface water
High levels of nitrate in the water can cause - Answer-blue baby syndrome
35 degrees Celsius is equivalent to what in Farhenheit - Answer-95
The mixing of coagulant chemicals in raw water is called - Answer-flash mixing
Sedimentation basins have _____ zones - Answer-four
The flow of a 48 inch pipe is 8590 gpm. What is the velocity? - Answer-1.52 fps
Chlorine gas is _________ times _____________ than air - Answer-2 and a half times
heavier
An approved air gap separation must be _________ - Answer-2 and a half times the
inside diameter or 3 inches, whichever is greater
Cathodic protection refers to ______ - Answer-corrossion
The two main substances that cause water hardness are - Answer-magnesium and
calcium
If you get a positive coliform sample what must be done - Answer-retake the original
sample plus one sample five upstream service connections and one sample within five
downstream service connections
When backwashing filters, bed expansion should be between what percent - Answer-
15-30%
The electronic flow meter reads 137,892, 900 gallons at 8:00 AM on Monday and
146,007,227 gallons at 8:00 AM on Tuesday. According to the scales 122 lbs of chlorine
was fed during the 24 hour period. Free chlorine readings entering the clear well read
0.8 mg/l What was the approximate chlorine demand of the raw water that day. -
Answer-1.0 mg/l
If the chlorine demand in the Water District was 1.2 ppm and the chlorine residual was
0.4 ppm what would the chlorine dosage be? - Answer-1.6 ppm
Latest Update
The best pH level for coagulation usually falls in the range of - Answer-5-7
Which, surface water or groundwater, usually contains a higher level of pathogens -
Answer-surface water
High levels of nitrate in the water can cause - Answer-blue baby syndrome
35 degrees Celsius is equivalent to what in Farhenheit - Answer-95
The mixing of coagulant chemicals in raw water is called - Answer-flash mixing
Sedimentation basins have _____ zones - Answer-four
The flow of a 48 inch pipe is 8590 gpm. What is the velocity? - Answer-1.52 fps
Chlorine gas is _________ times _____________ than air - Answer-2 and a half times
heavier
An approved air gap separation must be _________ - Answer-2 and a half times the
inside diameter or 3 inches, whichever is greater
Cathodic protection refers to ______ - Answer-corrossion
The two main substances that cause water hardness are - Answer-magnesium and
calcium
If you get a positive coliform sample what must be done - Answer-retake the original
sample plus one sample five upstream service connections and one sample within five
downstream service connections
When backwashing filters, bed expansion should be between what percent - Answer-
15-30%
The electronic flow meter reads 137,892, 900 gallons at 8:00 AM on Monday and
146,007,227 gallons at 8:00 AM on Tuesday. According to the scales 122 lbs of chlorine
was fed during the 24 hour period. Free chlorine readings entering the clear well read
0.8 mg/l What was the approximate chlorine demand of the raw water that day. -
Answer-1.0 mg/l
If the chlorine demand in the Water District was 1.2 ppm and the chlorine residual was
0.4 ppm what would the chlorine dosage be? - Answer-1.6 ppm
