Water Treatment Operator Level 1
Sample Questions with answers
What are the two important factors impacting the effectiveness of chlorination? - -
Concentration of chlorine and contact time
-The treatment process that controls corrosion or scaling is known as what? - -
Stabilization
-Permanganate reactions are highly dependent on what factor? - -pH
-It is hardest to kill the organism that causes what illness? - -Cryptosporidiosis
-Disinfection of water wells with free chlorine requires exposure for how long and at
what concentration? - -12 to 24 hours; 50mg/L
-Flocculation basins are usually designed to provide for detention times of how
long? - -15 to 45 minutes
-Alum works best in a pH range of what? - -5.8 to 7.5
-What has little effect on colloidal particles because of their small size? - -Gravity
-What natural electrical force keeps colloidal particles apart in water treatment? - -
Zeta potential
-What does the zeta potential measure? - -The number of excess electrons found
on the surface of all particulate matter
-What device collects the settled water as it leaves the sedimentation basin? - -The
effluent launder
-In solid-contact basins with fairly constant water quality parameters, how often
should the solids concentration be determined? - -At least twice per day
-What is the definition of decant? - -To draw off the liquid from a vessel of any size
without stirring up bottom sedimentation
-How often should sedimentation basins with mechanical sludge removal
equipment be drained and inspected? - -Once a year
-What is the most important reason to reduce turbidity? - -To remove pathogens
-What is the filtration flow rate through a manganese greensand pressure filter at
10 degrees C? - -2 to 3 gpm/sq ft
-When is a filter ripening? - -When it becomes more efficient in particle removal
Sample Questions with answers
What are the two important factors impacting the effectiveness of chlorination? - -
Concentration of chlorine and contact time
-The treatment process that controls corrosion or scaling is known as what? - -
Stabilization
-Permanganate reactions are highly dependent on what factor? - -pH
-It is hardest to kill the organism that causes what illness? - -Cryptosporidiosis
-Disinfection of water wells with free chlorine requires exposure for how long and at
what concentration? - -12 to 24 hours; 50mg/L
-Flocculation basins are usually designed to provide for detention times of how
long? - -15 to 45 minutes
-Alum works best in a pH range of what? - -5.8 to 7.5
-What has little effect on colloidal particles because of their small size? - -Gravity
-What natural electrical force keeps colloidal particles apart in water treatment? - -
Zeta potential
-What does the zeta potential measure? - -The number of excess electrons found
on the surface of all particulate matter
-What device collects the settled water as it leaves the sedimentation basin? - -The
effluent launder
-In solid-contact basins with fairly constant water quality parameters, how often
should the solids concentration be determined? - -At least twice per day
-What is the definition of decant? - -To draw off the liquid from a vessel of any size
without stirring up bottom sedimentation
-How often should sedimentation basins with mechanical sludge removal
equipment be drained and inspected? - -Once a year
-What is the most important reason to reduce turbidity? - -To remove pathogens
-What is the filtration flow rate through a manganese greensand pressure filter at
10 degrees C? - -2 to 3 gpm/sq ft
-When is a filter ripening? - -When it becomes more efficient in particle removal
