CA Wastewater Grade 3 sample Questions with Verified Answers| Latest Update Graded A+
When making a change to the activated sludge process how long should you
give the process to stabilize?
A. 1 week
B. 12 hours
C. 2 shifts
D. 2 days
E. 30 days A
When nitrifying ammonia, it is important to maintain adequate DO in the
mixed liquor to
A. prevent denitrification and sludge bulking in the secondary clarifier.
B. A low DO is actually better in the mixed liquor.
C. prevent ammonia from being converted to nitrite and than nitrate.
D. increase the chlorine demand.
E. reduce the aeration basin float. A
Pure oxygen plants are
A. normally not equipped with alarms because pure oxygen in harmless.
B. relative easy to operate and maintain.
C. normally found with conventional activated sludge plants.
D. normally equipped with many alarms and signals due to the dangers and
difficulty of the process.
E. Not used for industrial waste treatment D
Sodium Hypochlorite when added to the wastewater will:
A. Decrease the pH.
,B. increase the pH.
C. not effect the pH.
D. not react with reducing agents in the wastewater.
E. not react with hydroxide. B
The main cost associated with a nitrified effluent from a conventional
activated sludge plant is
A. chemical cost.
B. blower electrical cost.
C. increased cost of safety supplies.
D. increased chlorine use.
E. increased basin size. B
Problems associated with lime usage are
A. plugged lines.
B. plugged feed equipment.
C. high pH.
D. dust problems.
E. All the above. E
Useful anaerobic digester control tests include
A. pH.
B. temperature.
C. volatile acid/alkalinity relationship.
D. iron concentration.
E. b and c. E
, The fusible plug on a chlorine cylinder melts at approximately what
temperature?
A. 116F - 135F
B. 100C - 125C
C. 156C - 165C
D. 106F - 125F
E. 156F - 165F E
The pH of a pond is normally lowest at:
A. Midnight
B. Noon
C. Late afternoon
D. Sunrise
E. Sunup D
Biological nitrogen removal will:
A. Increase temperature.
B. Decrease temperature.
C. Not change alkalinity.
D. Increase alkalinity.
E. Decrease alkalinity. E
Given the following information about an activated sludge plant, determine at
what concentration the MLVSS should be maintained. F/M = 0.5, Primary effluent
BOD = 100 mg/L, Daily Q = 5.0 MGD, Effluent BOD 20 mg/L, Aerator volume =
1.0 MG , Return rate = 2.0 MGD. 1,000 mg/L
When making a change to the activated sludge process how long should you
give the process to stabilize?
A. 1 week
B. 12 hours
C. 2 shifts
D. 2 days
E. 30 days A
When nitrifying ammonia, it is important to maintain adequate DO in the
mixed liquor to
A. prevent denitrification and sludge bulking in the secondary clarifier.
B. A low DO is actually better in the mixed liquor.
C. prevent ammonia from being converted to nitrite and than nitrate.
D. increase the chlorine demand.
E. reduce the aeration basin float. A
Pure oxygen plants are
A. normally not equipped with alarms because pure oxygen in harmless.
B. relative easy to operate and maintain.
C. normally found with conventional activated sludge plants.
D. normally equipped with many alarms and signals due to the dangers and
difficulty of the process.
E. Not used for industrial waste treatment D
Sodium Hypochlorite when added to the wastewater will:
A. Decrease the pH.
,B. increase the pH.
C. not effect the pH.
D. not react with reducing agents in the wastewater.
E. not react with hydroxide. B
The main cost associated with a nitrified effluent from a conventional
activated sludge plant is
A. chemical cost.
B. blower electrical cost.
C. increased cost of safety supplies.
D. increased chlorine use.
E. increased basin size. B
Problems associated with lime usage are
A. plugged lines.
B. plugged feed equipment.
C. high pH.
D. dust problems.
E. All the above. E
Useful anaerobic digester control tests include
A. pH.
B. temperature.
C. volatile acid/alkalinity relationship.
D. iron concentration.
E. b and c. E
, The fusible plug on a chlorine cylinder melts at approximately what
temperature?
A. 116F - 135F
B. 100C - 125C
C. 156C - 165C
D. 106F - 125F
E. 156F - 165F E
The pH of a pond is normally lowest at:
A. Midnight
B. Noon
C. Late afternoon
D. Sunrise
E. Sunup D
Biological nitrogen removal will:
A. Increase temperature.
B. Decrease temperature.
C. Not change alkalinity.
D. Increase alkalinity.
E. Decrease alkalinity. E
Given the following information about an activated sludge plant, determine at
what concentration the MLVSS should be maintained. F/M = 0.5, Primary effluent
BOD = 100 mg/L, Daily Q = 5.0 MGD, Effluent BOD 20 mg/L, Aerator volume =
1.0 MG , Return rate = 2.0 MGD. 1,000 mg/L
