CA Wastewater Grade 3 Examination / 2025-
2026 Newest Version with Exam Focused
Questions and Reliable Answers / Guaranteed
Pass / Already Graded A+
When performing a BOD5 test, what is the significance of the seed
materiel.
It introduces the necessary microorganisms to decompose organic
matter
A Wastewater treatment plant uses a pump that operates at a flow rate
of 200 gallons per minute (GPM). If the pump runs continuously for 12
hrs a day, How many gallons does it pump a day/
144,000 gal/day
200 GPM x 60 min per hr x 12 hrs =
The White thick billowing foam common during the start-up of an
activated sludge wastewater treatment plant is caused by a low F/M
ratio?
T/F
F
High F or Low M
A wastewater sample has a high COD (Chemical oxygen demand)
what does this indicate?
High levels of organic and inorganic compounds
COD measures the total oxygen required to chemically oxidize all
substances in the sample. This provides a broader picture of pollution
load than BOD5
,A wastewater treatment plants SCADA system reports that the flow
into a treatment basin is 500,000 over a 24 hr period. What is the
average daily flow rate into the basin in gallons per minute (GPM)?
347.22 GPM
500,000 GPD / = 347.22
The most probable cause of denitrification in an activated sludge
plant is..
The failure to return the settled mixed liquor to the aeration basin
soon enough
what operational decision is informed by measurements of settleable
solids?
Determining when to increase sludge wasting rates to manage sludge
blankets.
A Wastewater treatment plant needs to replace a motor in one of its
pumps. The new motor has a HP rating of 10HP and operates at an
efficiency of 85%. What's the actual horsepower available for the
pump's operation?
8.5 HP
10HP x 0.85 Eff = 8.5
Temperature, altitude, and TDS all affect the amount of DO that can
dissolve in water
T/F
True, all of these lower DO
In wastewater treatment, the term CBOD refers to what?
Carbonaceous Biochemical Oxygen Demand
This is the amount of oxygen required to biologically oxidize carbon-
based compounds in wastewater.
A centrifugal pump is used to transfer sludge. If the pump has a flow
of 150 GPM and operates for 4 hrs a day, how many gallons of sludge
does it transfer daily?
36,000 gallons a day
150 GPM x 60 min x 4 hrs =
, Which of the following is sometimes used as an additive in correcting
anaerobic digester upsets?
a. ferrous chloride
b. anhydrous ammonia
c. ferric chloride
d. HTH
e. quicklime
b. anhydrous ammonia
Which test is used to determine the concentration of suspended
solids in wastewater.
Total Suspended solids (TSS)
NPDES stands for..
National Pollutant Discharge Elimination System
in a complete-mix activated sludge plant, the rate of oxygen uptake
per unit of activated sludge is about the same throughout the entire
aeration basin.
T/F
True
In laboratory analysis why is BOD testing important for wastewater
treatment?
It assesses the biodegradable organic matter present.
both carbon dioxide and ferrous sulfide are toxic gasses with
offensive odors.
T/F
False, carbon dioxide (C02) is odorless
A plants aeration system uses blowers that each operate at 1200
cubic ft/min. If this plant uses 3 blowers for 8 hours a day, what is the
total volume of air provided per day?
1,728,000 ctf
1200cft x 3 blowers x 8hrs x 60min
2026 Newest Version with Exam Focused
Questions and Reliable Answers / Guaranteed
Pass / Already Graded A+
When performing a BOD5 test, what is the significance of the seed
materiel.
It introduces the necessary microorganisms to decompose organic
matter
A Wastewater treatment plant uses a pump that operates at a flow rate
of 200 gallons per minute (GPM). If the pump runs continuously for 12
hrs a day, How many gallons does it pump a day/
144,000 gal/day
200 GPM x 60 min per hr x 12 hrs =
The White thick billowing foam common during the start-up of an
activated sludge wastewater treatment plant is caused by a low F/M
ratio?
T/F
F
High F or Low M
A wastewater sample has a high COD (Chemical oxygen demand)
what does this indicate?
High levels of organic and inorganic compounds
COD measures the total oxygen required to chemically oxidize all
substances in the sample. This provides a broader picture of pollution
load than BOD5
,A wastewater treatment plants SCADA system reports that the flow
into a treatment basin is 500,000 over a 24 hr period. What is the
average daily flow rate into the basin in gallons per minute (GPM)?
347.22 GPM
500,000 GPD / = 347.22
The most probable cause of denitrification in an activated sludge
plant is..
The failure to return the settled mixed liquor to the aeration basin
soon enough
what operational decision is informed by measurements of settleable
solids?
Determining when to increase sludge wasting rates to manage sludge
blankets.
A Wastewater treatment plant needs to replace a motor in one of its
pumps. The new motor has a HP rating of 10HP and operates at an
efficiency of 85%. What's the actual horsepower available for the
pump's operation?
8.5 HP
10HP x 0.85 Eff = 8.5
Temperature, altitude, and TDS all affect the amount of DO that can
dissolve in water
T/F
True, all of these lower DO
In wastewater treatment, the term CBOD refers to what?
Carbonaceous Biochemical Oxygen Demand
This is the amount of oxygen required to biologically oxidize carbon-
based compounds in wastewater.
A centrifugal pump is used to transfer sludge. If the pump has a flow
of 150 GPM and operates for 4 hrs a day, how many gallons of sludge
does it transfer daily?
36,000 gallons a day
150 GPM x 60 min x 4 hrs =
, Which of the following is sometimes used as an additive in correcting
anaerobic digester upsets?
a. ferrous chloride
b. anhydrous ammonia
c. ferric chloride
d. HTH
e. quicklime
b. anhydrous ammonia
Which test is used to determine the concentration of suspended
solids in wastewater.
Total Suspended solids (TSS)
NPDES stands for..
National Pollutant Discharge Elimination System
in a complete-mix activated sludge plant, the rate of oxygen uptake
per unit of activated sludge is about the same throughout the entire
aeration basin.
T/F
True
In laboratory analysis why is BOD testing important for wastewater
treatment?
It assesses the biodegradable organic matter present.
both carbon dioxide and ferrous sulfide are toxic gasses with
offensive odors.
T/F
False, carbon dioxide (C02) is odorless
A plants aeration system uses blowers that each operate at 1200
cubic ft/min. If this plant uses 3 blowers for 8 hours a day, what is the
total volume of air provided per day?
1,728,000 ctf
1200cft x 3 blowers x 8hrs x 60min
