Water Treatment Operator Certification
Study Guide (AWWA) Questions and
Answers
A continuously flowing watercourse Ans: Perennial Stream
Algae causes PH to ....... at night Ans: Decrease
What contributes to creation of algae blooms Ans: Increased
nutrients
Iron is found mostly in what sources of water Ans: Groundwater
Also called the rule of reasonable sharing Ans: Riparian Doctrine
Water high in salinity and warm is Ans: Low in dissolved oxygen
Reservoir turnover Ans: Denser water at surface sinking toward
the bottom
Water that flows into rivers after rainfall Ans: Surface runoff
Recreation can ....... of land adjacent to a reservoir Ans: increase
the threat of erosion
Water bearing geological zone composed of material deposited by
flowing rivers Ans: Alluvial aquifer
What effect will algae have on dissolved oxygen Ans: Increase DO
during the day and lower DO during the night
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How does alkalinity effect the use of copper sulfate Ans: Copper
sulfate is more effective as alkalinity decreases
The amount of water in a formation depends on..... Ans: The
porosity of the water-bearing formation
What enables blue green algae to grow Ans: Nutrients
Recommended loading rate of copper sulfate for algae control
Ans: 5.4 lbs per acre of surface area
Primary origin of coliform bacteria Ans: Animal or human feces
Amount of water a well produces for each foot of drawdown Ans:
Specific capacity
Most common well used in public water supply Ans: Drilled well
What is disinfection Ans: inactivation or killing of pathogenic
organisms
free chlorine residual valus are based on a contact time of.... Ans:
10 minutes
Strength of Calcium Hypochlorite Ans: 65-70%
What chemicals raise PH in water Ans: Soda Ash, Caustic Soda,
As water temp increases, disinfection action....... Ans: Increases
Maximum chlorine usage per day from a 150lb cylinder Ans: 42
lbs
What chemical is used to soften water through chemical
precipitation Ans: Calcium hydroxide (lime)
Mudballs are clumps of........ Ans: Filter media and other material
Coagulation occurs during the first ..... Ans: 1 to 5 seconds
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