CWEA ENVIROMENTAL COMPLIAMCE INSPECTOR
ANSWERS|LATEST !!!!2026|GRADED A+| (EXAM
Floatable solids are easy to measure. True or False? - ANSWER False
A well operated digester normally receives sludge at about __________% volatile solid and
reduces it to about ________________% volatile solids. - ANSWER 70-75%, 25-30%
According to OSHA, which of the following oxygen in air concentration is the lowest safe
concentration for humans to breathe in order to avoid the hazard of oxygen deficiency? -
ANSWER 19.5% oxygen
The population equivalent factor for BOD is - ANSWER 0.17 lb/day/BOD/person
Which microorganisms are found in a good settling mixed liquor? -
ANSWER Rotifers, stalked ciliates, and free swimming ciliates
Which heavy metal is the most stringent for land application? - ANSWER Mercury
Grit chambers that are designed to remove grit at a velocity of - ANSWER 0.5 to 1.0
ft/sec
The purpose of adding sodium thiosulfate to a microbiological (such as fecal coliform)
sample bottle is to - ANSWER Remove any chlorine residual present
1
,Which of the following types of wastewater would settling occur most rapidly?
Cold wastewater
Old wastewater
Septic wastewater
Strong wastewater - ANSWER Strong wastewater
The disadvantage of using a constant percentage return activated sludge flow control is -
ANSWER Clarifier is subjected to maximum solids loading when it contains
maximum amount of sludge
Under which conditions should sludge wasting normally be increased? - ANSWER A
dark brown scummy foam appears on the aeration tank surface
The outlet of a forced ventilation system for a chlorinator room should be located -
ANSWER Near the floor
If packing is not maintained properly - ANSWER There will be a loss of suction from
air being allowed to enter the pipe.
Turbidity in wastewater is caused by - ANSWER Finely divided suspended material
One of the primary reasons why air should be excluded from the digester is that... -
ANSWER The entrance of air mixed with gas produced in the digester could create
an explosive mixture
True or False: Barminutors and comminutors are installed for different purposes -
ANSWER False
2
, What are the end products of the aerobic biochemical reaction? - ANSWER H2O and
CO2
What does pump maintenance include?
a. Checking operating temperatures of bearings
b. checking packings glands
c. lubricating the impeller
d. all of the above - ANSWER all of the above
Pump packing should be - ANSWER Tightened down to a drip
The fusible plug that is in all chlorine containers?
a. May be used as a tap for the chlorine source
b. Should be removed after the cylinders are empty
c. Should never be removed or tampered with
d. Should be removed prior to withdrawing chlorine from the container -
ANSWER Should never be removed or tampered with
A piston or diaphragm pump would be used for pumping... - ANSWER Primary
sludge
Collection system variables that could upset an activated sludge process include... -
ANSWER Activities of collection system maintenance crew
What type of pump is not seriously damaged if the discharge valve is closed for a short time,
while the pump is running? - ANSWER Centrifugal pump
3
ANSWERS|LATEST !!!!2026|GRADED A+| (EXAM
Floatable solids are easy to measure. True or False? - ANSWER False
A well operated digester normally receives sludge at about __________% volatile solid and
reduces it to about ________________% volatile solids. - ANSWER 70-75%, 25-30%
According to OSHA, which of the following oxygen in air concentration is the lowest safe
concentration for humans to breathe in order to avoid the hazard of oxygen deficiency? -
ANSWER 19.5% oxygen
The population equivalent factor for BOD is - ANSWER 0.17 lb/day/BOD/person
Which microorganisms are found in a good settling mixed liquor? -
ANSWER Rotifers, stalked ciliates, and free swimming ciliates
Which heavy metal is the most stringent for land application? - ANSWER Mercury
Grit chambers that are designed to remove grit at a velocity of - ANSWER 0.5 to 1.0
ft/sec
The purpose of adding sodium thiosulfate to a microbiological (such as fecal coliform)
sample bottle is to - ANSWER Remove any chlorine residual present
1
,Which of the following types of wastewater would settling occur most rapidly?
Cold wastewater
Old wastewater
Septic wastewater
Strong wastewater - ANSWER Strong wastewater
The disadvantage of using a constant percentage return activated sludge flow control is -
ANSWER Clarifier is subjected to maximum solids loading when it contains
maximum amount of sludge
Under which conditions should sludge wasting normally be increased? - ANSWER A
dark brown scummy foam appears on the aeration tank surface
The outlet of a forced ventilation system for a chlorinator room should be located -
ANSWER Near the floor
If packing is not maintained properly - ANSWER There will be a loss of suction from
air being allowed to enter the pipe.
Turbidity in wastewater is caused by - ANSWER Finely divided suspended material
One of the primary reasons why air should be excluded from the digester is that... -
ANSWER The entrance of air mixed with gas produced in the digester could create
an explosive mixture
True or False: Barminutors and comminutors are installed for different purposes -
ANSWER False
2
, What are the end products of the aerobic biochemical reaction? - ANSWER H2O and
CO2
What does pump maintenance include?
a. Checking operating temperatures of bearings
b. checking packings glands
c. lubricating the impeller
d. all of the above - ANSWER all of the above
Pump packing should be - ANSWER Tightened down to a drip
The fusible plug that is in all chlorine containers?
a. May be used as a tap for the chlorine source
b. Should be removed after the cylinders are empty
c. Should never be removed or tampered with
d. Should be removed prior to withdrawing chlorine from the container -
ANSWER Should never be removed or tampered with
A piston or diaphragm pump would be used for pumping... - ANSWER Primary
sludge
Collection system variables that could upset an activated sludge process include... -
ANSWER Activities of collection system maintenance crew
What type of pump is not seriously damaged if the discharge valve is closed for a short time,
while the pump is running? - ANSWER Centrifugal pump
3
