Water Distribution Exam | 50
Questions and Answers Verified 100%
Correct
Wear rings in a centrifugal pump are designed to
a. prevent excessive internal water circulation between the suction and discharge
sides of a pump
b. prevent wear of the impeller and inside case
c. allow excessive internal water circulation to occur between the suction and discharge d.
both a & b are correct, but not c - ANSWER d. both a & b are correct, but not c
Packing ring notches in a centrifugal type pump should be ______ when placed in the
stuffing box?
a. water tight
b. staggered 90º
c. made of rubber not metal
d. heated - ANSWER b. staggered 90º
Eighty parts per billion (80 ppb) is equal to which of the following?
a. 8 ppm
b. 0.8 mg/L
c. 0.08 mg/L
d. 80 mg/L - ANSWER c. 0.08 mg/L
, A mass of concrete placed at bends and valve structures to prevent pipeline
movement is commonly called a
a. thrust block
c. curb stop
b. corp stop
d. service block - ANSWER a. thrust block
What is the main difference between surface and groundwater contamination?
a. groundwater takes longer to recover after contamination
b. groundwaters are less susceptible to contamination
c. surface waters take longer to recover
d. surface waters are usually harder and more difficult to recover - ANSWER a.
groundwater takes longer to recover after contamination
What constitutes a cross-connection?
a. a connection between an approved and an unapproved water supply
b. an unprotected connection between a drinking water supply and a system not
approved as safe
c. a connection between a contaminated supply and non-potable supplies
d. all of the above - ANSWER a. a connection between an approved and an unapproved
water supply
According to the Center for Disease Control (CDC), which mechanism or problem has
caused more waterborne disease outbreaks (WDO) in the United States than any
other reported factor?
a. inadequate O&M of filtering systems
b. lack of chlorination
Questions and Answers Verified 100%
Correct
Wear rings in a centrifugal pump are designed to
a. prevent excessive internal water circulation between the suction and discharge
sides of a pump
b. prevent wear of the impeller and inside case
c. allow excessive internal water circulation to occur between the suction and discharge d.
both a & b are correct, but not c - ANSWER d. both a & b are correct, but not c
Packing ring notches in a centrifugal type pump should be ______ when placed in the
stuffing box?
a. water tight
b. staggered 90º
c. made of rubber not metal
d. heated - ANSWER b. staggered 90º
Eighty parts per billion (80 ppb) is equal to which of the following?
a. 8 ppm
b. 0.8 mg/L
c. 0.08 mg/L
d. 80 mg/L - ANSWER c. 0.08 mg/L
, A mass of concrete placed at bends and valve structures to prevent pipeline
movement is commonly called a
a. thrust block
c. curb stop
b. corp stop
d. service block - ANSWER a. thrust block
What is the main difference between surface and groundwater contamination?
a. groundwater takes longer to recover after contamination
b. groundwaters are less susceptible to contamination
c. surface waters take longer to recover
d. surface waters are usually harder and more difficult to recover - ANSWER a.
groundwater takes longer to recover after contamination
What constitutes a cross-connection?
a. a connection between an approved and an unapproved water supply
b. an unprotected connection between a drinking water supply and a system not
approved as safe
c. a connection between a contaminated supply and non-potable supplies
d. all of the above - ANSWER a. a connection between an approved and an unapproved
water supply
According to the Center for Disease Control (CDC), which mechanism or problem has
caused more waterborne disease outbreaks (WDO) in the United States than any
other reported factor?
a. inadequate O&M of filtering systems
b. lack of chlorination
