Grade 4 CA Wastewater Exam |\ |\ |\ |\ |\
QUESTIONS WITH ANSWERS |\ |\
3 considerations, besides does, that impact the effectiveness of
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UV. - CORRECT ANSWERS ✔✔Water Clarity
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Water hardness (causes build up on lamps)
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Frequency of lamp cleaning |\ |\ |\
Units on MCRT - CORRECT ANSWERS ✔✔S = lb MLSS in system
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(AB + Secondary Clarifiers0
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E(dot) = lb/d TSS unintentionally removed in effluent
|\ |\ |\ |\ |\ |\ |\
W(dot) = lb/d TSS intentionally removed in WAS
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Conventional Activated Sludge: MCRT, F:M, Organic Loading, |\ |\ |\ |\ |\ |\ |\
MLSS mg/L, Aeration Basin HRT (hours), Qras % of Q - CORRECT
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ANSWERS ✔✔MCRT = 5 - 15 Days |\ |\ |\ |\ |\ |\
F:M = 0.2 - 0.4 lb BOD/d*lb MLVSS
|\ |\ |\ |\ |\ |\ |\
OL = 20 - 40 lb BOD/d*1000 ft^3
|\ |\ |\ |\ |\ |\ |\
MLSS = 1500 - 3000 mg/L |\ |\ |\ |\ |\
HRT = 4 - 8 hours |\ |\ |\ |\ |\
Qras% = 25 to 50% of Q |\ |\ |\ |\ |\ |\
Extended Aeration Activated Sludge: MCRT, F:M, Organic Loading,
|\ |\ |\ |\ |\ |\ |\
MLSS mg/L, Aeration Basin HRT (hours), Qras % of Q - CORRECT
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
ANSWERS ✔✔MCRT = 20 - 30 Days |\ |\ |\ |\ |\ |\
,F:M = 0.05 - 0.15 lb BOD/d*lb MLVSS
|\ |\ |\ |\ |\ |\ |\
OL = 10 - 25 lb BOD/d*1000 ft^3
|\ |\ |\ |\ |\ |\ |\
MLSS = 3000 - 6000 mg/L|\ |\ |\ |\ |\
HRT = 18 - 16 hours
|\ |\ |\ |\ |\
Qras% = 75 to 150% of Q |\ |\ |\ |\ |\ |\
Contact-Stabilization Activated Sludge: MCRT, F:M, Organic |\ |\ |\ |\ |\ |\
Loading, MLSS mg/L, Aeration Basin HRT (hours), Qras % of Q -
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
CORRECT ANSWERS ✔✔MCRT = 5 - 15 Days |\ |\ |\ |\ |\ |\ |\
F:M = 0.2 - 0.6 lb BOD/d*lb MLVSS
|\ |\ |\ |\ |\ |\ |\
OL = 60 - 75 lb BOD/d*1000 ft^3
|\ |\ |\ |\ |\ |\ |\
MLSS = Contact: 1000 - 3000 mg/L, Stabilisation: 4000 - 10,000
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\
HRT = Contact: 0.5 - 1 hours, Stabilisation: 3 - 6 hours
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
Qras% = 25 to 100% of Q |\ |\ |\ |\ |\ |\
Step Feed Activated Sludge: MCRT, F:M, Organic Loading, MLSS
|\ |\ |\ |\ |\ |\ |\ |\ |\
mg/L, Aeration Basin HRT (hours), Qras % of Q - CORRECT
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
ANSWERS ✔✔MCRT = 5 - 15 Days |\ |\ |\ |\ |\ |\
F:M = 0.2 - 0.4 lb BOD/d*lb MLVSS
|\ |\ |\ |\ |\ |\ |\
OL = 20 - 40 lb BOD/d*1000 ft^3
|\ |\ |\ |\ |\ |\ |\
MLSS = 2000 - 3500 mg/L|\ |\ |\ |\ |\
HRT = 3 - 5 hours
|\ |\ |\ |\ |\
Qras% = 25 to 75% of Q |\ |\ |\ |\ |\ |\
, Complete Mix Activated Sludge: MCRT, F:M, Organic Loading,|\ |\ |\ |\ |\ |\ |\ |\
MLSS mg/L, Aeration Basin HRT (hours), Qras % of Q - CORRECT
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
ANSWERS ✔✔MCRT = 5 - 15 Days |\ |\ |\ |\ |\ |\
F:M = 0.2 - 0.6 lb BOD/d*lb MLVSS
|\ |\ |\ |\ |\ |\ |\
OL = 50 - 120 lb BOD/d*1000 ft^3
|\ |\ |\ |\ |\ |\ |\
MLSS = 3000 - 6000 mg/L |\ |\ |\ |\ |\
HRT = 3 - 5 hours |\ |\ |\ |\ |\
Qras% = 25 to 100% of Q |\ |\ |\ |\ |\ |\
T/F: When measuring VA in an anaerobic digester, the final step
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
is to titrate the sample with sulfuric acid. - CORRECT ANSWERS
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
✔✔False: Titrate 0.1 N of Sodium hydroxide to the |\ |\ |\ |\ |\ |\ |\ |\ |\
phenolphthalein endpoint (pH =8.3) |\ |\ |\
In order for denitrification to occur, what must happen first? (3
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
items) - CORRECT ANSWERS ✔✔Nitrate must be present
|\ |\ |\ |\ |\ |\ |\
Oxygen must be present |\ |\ |\
Readily available degradable BOD present |\ |\ |\ |\
3 criteria for valid BOD results - CORRECT ANSWERS ✔✔DO
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consumed in the blank must be <0.2 mg/L |\ |\ |\ |\ |\ |\ |\
DO remaining in each sample bottle >1.0 mg/L
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DO consumed in each sample bottle >2.0 mg/L
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Units on the F:M ratio - CORRECT ANSWERS ✔✔Lb BOD / d*lb
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MLVSS
QUESTIONS WITH ANSWERS |\ |\
3 considerations, besides does, that impact the effectiveness of
|\ |\ |\ |\ |\ |\ |\ |\ |\
UV. - CORRECT ANSWERS ✔✔Water Clarity
|\ |\ |\ |\ |\
Water hardness (causes build up on lamps)
|\ |\ |\ |\ |\ |\
Frequency of lamp cleaning |\ |\ |\
Units on MCRT - CORRECT ANSWERS ✔✔S = lb MLSS in system
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
(AB + Secondary Clarifiers0
|\ |\ |\
E(dot) = lb/d TSS unintentionally removed in effluent
|\ |\ |\ |\ |\ |\ |\
W(dot) = lb/d TSS intentionally removed in WAS
|\ |\ |\ |\ |\ |\ |\
Conventional Activated Sludge: MCRT, F:M, Organic Loading, |\ |\ |\ |\ |\ |\ |\
MLSS mg/L, Aeration Basin HRT (hours), Qras % of Q - CORRECT
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
ANSWERS ✔✔MCRT = 5 - 15 Days |\ |\ |\ |\ |\ |\
F:M = 0.2 - 0.4 lb BOD/d*lb MLVSS
|\ |\ |\ |\ |\ |\ |\
OL = 20 - 40 lb BOD/d*1000 ft^3
|\ |\ |\ |\ |\ |\ |\
MLSS = 1500 - 3000 mg/L |\ |\ |\ |\ |\
HRT = 4 - 8 hours |\ |\ |\ |\ |\
Qras% = 25 to 50% of Q |\ |\ |\ |\ |\ |\
Extended Aeration Activated Sludge: MCRT, F:M, Organic Loading,
|\ |\ |\ |\ |\ |\ |\
MLSS mg/L, Aeration Basin HRT (hours), Qras % of Q - CORRECT
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
ANSWERS ✔✔MCRT = 20 - 30 Days |\ |\ |\ |\ |\ |\
,F:M = 0.05 - 0.15 lb BOD/d*lb MLVSS
|\ |\ |\ |\ |\ |\ |\
OL = 10 - 25 lb BOD/d*1000 ft^3
|\ |\ |\ |\ |\ |\ |\
MLSS = 3000 - 6000 mg/L|\ |\ |\ |\ |\
HRT = 18 - 16 hours
|\ |\ |\ |\ |\
Qras% = 75 to 150% of Q |\ |\ |\ |\ |\ |\
Contact-Stabilization Activated Sludge: MCRT, F:M, Organic |\ |\ |\ |\ |\ |\
Loading, MLSS mg/L, Aeration Basin HRT (hours), Qras % of Q -
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
CORRECT ANSWERS ✔✔MCRT = 5 - 15 Days |\ |\ |\ |\ |\ |\ |\
F:M = 0.2 - 0.6 lb BOD/d*lb MLVSS
|\ |\ |\ |\ |\ |\ |\
OL = 60 - 75 lb BOD/d*1000 ft^3
|\ |\ |\ |\ |\ |\ |\
MLSS = Contact: 1000 - 3000 mg/L, Stabilisation: 4000 - 10,000
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\
HRT = Contact: 0.5 - 1 hours, Stabilisation: 3 - 6 hours
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
Qras% = 25 to 100% of Q |\ |\ |\ |\ |\ |\
Step Feed Activated Sludge: MCRT, F:M, Organic Loading, MLSS
|\ |\ |\ |\ |\ |\ |\ |\ |\
mg/L, Aeration Basin HRT (hours), Qras % of Q - CORRECT
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
ANSWERS ✔✔MCRT = 5 - 15 Days |\ |\ |\ |\ |\ |\
F:M = 0.2 - 0.4 lb BOD/d*lb MLVSS
|\ |\ |\ |\ |\ |\ |\
OL = 20 - 40 lb BOD/d*1000 ft^3
|\ |\ |\ |\ |\ |\ |\
MLSS = 2000 - 3500 mg/L|\ |\ |\ |\ |\
HRT = 3 - 5 hours
|\ |\ |\ |\ |\
Qras% = 25 to 75% of Q |\ |\ |\ |\ |\ |\
, Complete Mix Activated Sludge: MCRT, F:M, Organic Loading,|\ |\ |\ |\ |\ |\ |\ |\
MLSS mg/L, Aeration Basin HRT (hours), Qras % of Q - CORRECT
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
ANSWERS ✔✔MCRT = 5 - 15 Days |\ |\ |\ |\ |\ |\
F:M = 0.2 - 0.6 lb BOD/d*lb MLVSS
|\ |\ |\ |\ |\ |\ |\
OL = 50 - 120 lb BOD/d*1000 ft^3
|\ |\ |\ |\ |\ |\ |\
MLSS = 3000 - 6000 mg/L |\ |\ |\ |\ |\
HRT = 3 - 5 hours |\ |\ |\ |\ |\
Qras% = 25 to 100% of Q |\ |\ |\ |\ |\ |\
T/F: When measuring VA in an anaerobic digester, the final step
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
is to titrate the sample with sulfuric acid. - CORRECT ANSWERS
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
✔✔False: Titrate 0.1 N of Sodium hydroxide to the |\ |\ |\ |\ |\ |\ |\ |\ |\
phenolphthalein endpoint (pH =8.3) |\ |\ |\
In order for denitrification to occur, what must happen first? (3
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
items) - CORRECT ANSWERS ✔✔Nitrate must be present
|\ |\ |\ |\ |\ |\ |\
Oxygen must be present |\ |\ |\
Readily available degradable BOD present |\ |\ |\ |\
3 criteria for valid BOD results - CORRECT ANSWERS ✔✔DO
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\
consumed in the blank must be <0.2 mg/L |\ |\ |\ |\ |\ |\ |\
DO remaining in each sample bottle >1.0 mg/L
|\ |\ |\ |\ |\ |\ |\
DO consumed in each sample bottle >2.0 mg/L
|\ |\ |\ |\ |\ |\ |\
Units on the F:M ratio - CORRECT ANSWERS ✔✔Lb BOD / d*lb
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
MLVSS
