CWEA ENVIRONMENTAL COMPLIANCE INSPECTOR GRADE 1
Questions with Correct Solutions
Question:
1. Floatable solids are easy to measure. True or False?
Answer:
False
Question:
2. A well operated digester normally receives sludge at about __________% volatile solid and
reduces it to about ________________% volatile solids.
Answer:
70-75%, 25-30%
Question:
3. 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
Question:
4. The population equivalent factor for BOD is
Answer:
0.17 lb/day/BOD/person
Question:
5. Which microorganisms are found in a good settling mixed liquor?
Answer:
Rotifers, stalked ciliates, and free swimming ciliates
Question:
6. Which heavy metal is the most stringent for land application?
Answer:
Mercury
Question:
7. Grit chambers that are designed to remove grit at a velocity of
,Answer:
0.5 to 1.0 ft/sec
Question:
8. The purpose of adding sodium thiosulfate to a microbiological (such as fecal coliform)
sample bottle is to
Answer:
Remove any chlorine residual present
Question:
9. Which of the following types of wastewater would settling occur most rapidly? Cold
wastewater Old wastewater Septic wastewater Strong wastewater
Answer:
Strong wastewater
Question:
10. 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
Question:
11. Under which conditions should sludge wasting normally be increased?
Answer:
A dark brown scummy foam appears on the aeration tank surface
Question:
12. The outlet of a forced ventilation system for a chlorinator room should be located
Answer:
Near the floor
Question:
13. If packing is not maintained properly
Answer:
There will be a loss of suction from air being allowed to enter the pipe.
Question:
14. Turbidity in wastewater is caused by
Answer:
Finely divided suspended material
, Question:
15. 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
Question:
16. True or False: Barminutors and comminutors are installed for different purposes
Answer:
False
Question:
17. What are the end products of the aerobic biochemical reaction?
Answer:
H2O and CO2
Question:
18. 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
Question:
19. Pump packing should be
Answer:
Tightened down to a drip
Question:
20. 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
Questions with Correct Solutions
Question:
1. Floatable solids are easy to measure. True or False?
Answer:
False
Question:
2. A well operated digester normally receives sludge at about __________% volatile solid and
reduces it to about ________________% volatile solids.
Answer:
70-75%, 25-30%
Question:
3. 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
Question:
4. The population equivalent factor for BOD is
Answer:
0.17 lb/day/BOD/person
Question:
5. Which microorganisms are found in a good settling mixed liquor?
Answer:
Rotifers, stalked ciliates, and free swimming ciliates
Question:
6. Which heavy metal is the most stringent for land application?
Answer:
Mercury
Question:
7. Grit chambers that are designed to remove grit at a velocity of
,Answer:
0.5 to 1.0 ft/sec
Question:
8. The purpose of adding sodium thiosulfate to a microbiological (such as fecal coliform)
sample bottle is to
Answer:
Remove any chlorine residual present
Question:
9. Which of the following types of wastewater would settling occur most rapidly? Cold
wastewater Old wastewater Septic wastewater Strong wastewater
Answer:
Strong wastewater
Question:
10. 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
Question:
11. Under which conditions should sludge wasting normally be increased?
Answer:
A dark brown scummy foam appears on the aeration tank surface
Question:
12. The outlet of a forced ventilation system for a chlorinator room should be located
Answer:
Near the floor
Question:
13. If packing is not maintained properly
Answer:
There will be a loss of suction from air being allowed to enter the pipe.
Question:
14. Turbidity in wastewater is caused by
Answer:
Finely divided suspended material
, Question:
15. 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
Question:
16. True or False: Barminutors and comminutors are installed for different purposes
Answer:
False
Question:
17. What are the end products of the aerobic biochemical reaction?
Answer:
H2O and CO2
Question:
18. 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
Question:
19. Pump packing should be
Answer:
Tightened down to a drip
Question:
20. 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
