FLORIDA WASTEWATER FINAL EXAM
2 VERSIONS 2025/2026 BANK
COMPLETE 550 QUESTIONS WITH
DETAILED VERIFIED ANSWERS (100%
CORRECT ANSWERS) /ALREADY
GRADED A+ // BRAND NEW!!
What are the two reaction-forming stages of anaerobic
digestion? - ....ANSWER...Acid and methane
What does the term "loading" refer to in the activated
sludge process? - ....ANSWER...Pounds of CBOD entering
the aeration tank
What happens to the chlorine residual when the organic
content in the effluent goes up? - ....ANSWER...The
residual goes down
What are the principal nutrients that must be removed
from effluent before it is safe for discharge to florida
water? - ....ANSWER...Nitrogen and Phosphorus
1
,What happens to the nitrated and pH in an aerobic
digester when the air is turned off for certain periods each
day? - ....ANSWER...Nitrates are decreased and the pH
increases
Given the following data, how many total gals/day of
sludge are removed from a primary clarifier using a triple
piston pump? Piston diameter is 12 inches; Length is 14
inches; Speed is 35SPM; Total run time is 250min/day -
....ANSWER...178,796 GPD
What is the liquid effluent called that is removed from an
anaerobic digester? - ....ANSWER...Supernatant
What is the formula that defines chlorine demand? -
....ANSWER...Supply - Residual = Demand
Which chemical is typically used for dechlorination of final
effluent? - ....ANSWER...Sulfur Dioxide
An anaerobic digester that has become unstable is referred
to as "stuck" or "sour". What might cause this condition? -
2
,....ANSWER...High acid production, Sludge feed rate too
high, Improper Mixing
What is the term that describes the combination of
ammonia-nitrogen, nitrate-nitrogen, and nitrite-nitrogen?
- ....ANSWER...Total Inorganic Nitrogen
A low F/M ratio, high MCRT, low SVI, and high MLSS
concentrations are all characteristic of? -
....ANSWER...Old sludge
In most activated sludge treatment plants the major cause
of repeated sludge bulking is? - ....ANSWER...High F/M
loading rate and low MCRT
When an anaerobic digester is operating correctly the
volatile acid to alkalinity ratio should be? -
....ANSWER...0.1 to 1.0
What is the first stage of the two part process of anaerobic
digestion? - ....ANSWER...Acid formation
SVI is best defined as? - ....ANSWER...The tendency of
activated solids to thicken or to become concentrated
3
, during the sedimentation/thickening process
What is the objective of wasting activated sludge? -
....ANSWER...Maintain a balance between
microorganisms under aeration and amount of incoming
food
A colored dye solution is added into the raw wastewater
entering a primary settling tank. The dye color was
noticeable in the effluent in 15 minutes and all of the color
had passed through the tank in 40 minutes. What does this
indicate? - ....ANSWER...Wastewater is passing through the
tank too quickly for effective settling
A spray field has a total of 80 acres and is divided into four
equal zones. Only one zone may be operated at a time and
the permit states that no more than 4 inches of water can
be applied to the zone. How long can a zone be operated at
a rate of 0.7 MGD before it must be rotated to another
zone? - ....ANSWER...3.1 days
4
2 VERSIONS 2025/2026 BANK
COMPLETE 550 QUESTIONS WITH
DETAILED VERIFIED ANSWERS (100%
CORRECT ANSWERS) /ALREADY
GRADED A+ // BRAND NEW!!
What are the two reaction-forming stages of anaerobic
digestion? - ....ANSWER...Acid and methane
What does the term "loading" refer to in the activated
sludge process? - ....ANSWER...Pounds of CBOD entering
the aeration tank
What happens to the chlorine residual when the organic
content in the effluent goes up? - ....ANSWER...The
residual goes down
What are the principal nutrients that must be removed
from effluent before it is safe for discharge to florida
water? - ....ANSWER...Nitrogen and Phosphorus
1
,What happens to the nitrated and pH in an aerobic
digester when the air is turned off for certain periods each
day? - ....ANSWER...Nitrates are decreased and the pH
increases
Given the following data, how many total gals/day of
sludge are removed from a primary clarifier using a triple
piston pump? Piston diameter is 12 inches; Length is 14
inches; Speed is 35SPM; Total run time is 250min/day -
....ANSWER...178,796 GPD
What is the liquid effluent called that is removed from an
anaerobic digester? - ....ANSWER...Supernatant
What is the formula that defines chlorine demand? -
....ANSWER...Supply - Residual = Demand
Which chemical is typically used for dechlorination of final
effluent? - ....ANSWER...Sulfur Dioxide
An anaerobic digester that has become unstable is referred
to as "stuck" or "sour". What might cause this condition? -
2
,....ANSWER...High acid production, Sludge feed rate too
high, Improper Mixing
What is the term that describes the combination of
ammonia-nitrogen, nitrate-nitrogen, and nitrite-nitrogen?
- ....ANSWER...Total Inorganic Nitrogen
A low F/M ratio, high MCRT, low SVI, and high MLSS
concentrations are all characteristic of? -
....ANSWER...Old sludge
In most activated sludge treatment plants the major cause
of repeated sludge bulking is? - ....ANSWER...High F/M
loading rate and low MCRT
When an anaerobic digester is operating correctly the
volatile acid to alkalinity ratio should be? -
....ANSWER...0.1 to 1.0
What is the first stage of the two part process of anaerobic
digestion? - ....ANSWER...Acid formation
SVI is best defined as? - ....ANSWER...The tendency of
activated solids to thicken or to become concentrated
3
, during the sedimentation/thickening process
What is the objective of wasting activated sludge? -
....ANSWER...Maintain a balance between
microorganisms under aeration and amount of incoming
food
A colored dye solution is added into the raw wastewater
entering a primary settling tank. The dye color was
noticeable in the effluent in 15 minutes and all of the color
had passed through the tank in 40 minutes. What does this
indicate? - ....ANSWER...Wastewater is passing through the
tank too quickly for effective settling
A spray field has a total of 80 acres and is divided into four
equal zones. Only one zone may be operated at a time and
the permit states that no more than 4 inches of water can
be applied to the zone. How long can a zone be operated at
a rate of 0.7 MGD before it must be rotated to another
zone? - ....ANSWER...3.1 days
4
