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CWEA COLLECTIONS GRADE 2 EXAM, CWEA ELECTRICAL AND
INSTRUMENT GRADE 2, CWEA CSM GRADE 2 EXAM LATEST
2024-2025 BEST 3 VERSIONS ALL QUESTIONS AND CORRECT
DETAILED ANSWERS ALREADY GRADED A+
CWEA COLLECTIONS GRADE 2 EXAM
The main reason for adding sodium hypochlorite to sewers is to control: - ANSWER-Odor
Roots can enter collection systems through pipe cracks, true or false? - ANSWER-True
The lowest point on the inside of a pipeline is called the: - ANSWER-Invert
How often must an excavation site and adjacent areas be inspected for hazardous conditions? - ANSWER-Daily
Working in an un-sloped trench with no shoring is one option of Protective Shoring Systems, true or false? - ANSWER-False. Some options are proper stopping or benching of the sides of the excavation, supporting the sides of a trench with shoring, and using a shield in the excavation area.
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2 Proper operation and maintenance of wastewater collection is keeping wastewater flowing through pipes, true or false? - ANSWER-True
Minimum design velocity for a sewer should greater than: - ANSWER-2 feet per second
Vitrified Clay pipe is a Rigid type of pipe, true or false? - ANSWER-True
Barrels, lids, cones, and backflow devices are all included in Manholes, true or false? - ANSWER- False. All are included except for backflow devices.
Sewer testing methods include air, water, mandrill, and sewage, true or false? - ANSWER-False.Sewer testing methods do not include sewage.
Using high velocity cleaners is one method included in hydraulic sewer cleaning, true or false? - ANSWER-True
A flow of 650 gpm would be how many MGD? - ANSWER-650 gpm x (1440 min / 1 day) = 936000 gpd 936000 x (1 MG / 1000000 gal) = 0.936 MGD
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3 One of the advantages of using CCTV is that the length and severity of defective pipe areas can be recorded, true or false? - ANSWER-True
Offset joints are one hazard that may damage a TV camera going through a sewer, true or false? - ANSWER-True
What is the total volume of 1000 feet of 8 inch line? - ANSWER-Convert inches to feet:
- inches x (1 foot / 12 inches) = 0.666
Volume of a right regular cylinder:
V = 0.785 x Diameter x Diameter x Length of Pipe V = 0.785 x 0.666 ft x 0.666 ft x 1000 ft V = 348.19 cu ft
Convert to gallons:
348.19 cu ft x (7.48 gal / 1 cu ft) = 2604.47 gal
If an 8 inch force main has a metered flow rate of 400000 gpd, what is the velocity? - ANSWER- Velocity = Flow / Area Area = 0.785 x Diameter x Diameter When finding Area, convert Diameter into feet
- in x (1 ft / 12 in) = 0.667 ft 3 / 4
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4 Area = 0.785 x 0.667 ft x 0.667 ft = 0.349 sq ft
Convert flow in gallons to cubic feet per second:
(400000 gal / 1 day) x (1 cu ft / 7.48 gal) x (1 day / 24 hours) x (1 hr / 60 min) x (1 min / 60 sec) = 0.619 cu fps Velocity = 0.619 cu fps / 0.349 sq ft Velocity = 1.77 fps
During the 24-hour operation a lift station pumped 3000 gallons per minute for a community of
- What is the per capita pumped in gallons per day? - ANSWER-GPD / Capita = Volume
Pumped Per Day / Number of people Volume = (3000 gal / 1 min) x (60 min / 1 hr) x (24 hr / 1 day) Volume = 4320000 gal GPD / Capita = 4320000 gal / 27000 people GPD / Capita = 160
A wet well 20 feet in diameter is filled with water to a depth of 10 feet. How many gallons does the tank contain? - ANSWER-Volume = 0.785 x Diameter x Diameter x Height Volume = 0.785 x 20 ft x 20 ft x 10 ft Volume = 3140 cu ft
Convert to gallons:
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