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問題一覧
1
Where are all service connections most likely to leak?
curb stop connection
2
What is the name of the document that lists a distribution systems, coliform sample schedule and sample sites?
Sample siting plan
3
A concrete block that is placed around the pipe usually at a bend, or intersection to prevent movement is called a
Thrust block
4
How often should the atomosphere be monitored during a confined space entry
Continuously
5
Asbestos cement pipe contains which of the following
Silica sand
6
What is the function of an air relief valve on a well?
to vent air in the well column of an off-line well
7
Which gas is lighter than air odorless highly flammable, and is sometimes referred to a swamp gas
Methane
8
if there is an ongoing problem with an operator; how should the supervisor handle it?
discuss the problem with the operator and document the problem in writing
9
What is the best way to prevent contaminating the Water main when installing a new service connection?
wet tap with system pressureized
10
Residential distribution system pressure should be limited to prevent the premature failure of
Water heaters and other water appliances
11
Customers will notice if distribution water turbidity exceeds _____ NTU
Five
12
which gas has a rotten egg odor
Hydrogen sulfide
13
what is the recommended maximum head loss for positive displacements meters smaller than two inches?
15 psi
14
What form provides hazard information?
MSDS
15
Which of the following pipe material is flexible cement, copper ,galvanized iron or steel
Copper
16
The recommended interval between testing a 5/8 inch meter is _____ years
10
17
what type of level indicator uses air in its operation
bubbler tube
18
A wet barrel fire hydrant has
A separate valve for each nozzle
19
what is the minimum contact time when? Using the chlorine tablet method for disinfection of a new main
24 hours
20
From the following list, which pump characteristics is shown on a pump curve?
Efficiency
21
What is the purpose of sodium thiosulfate in coliform sample bottles?
Remove chlorine residual
22
if a water main breaks what should be the first action of the distribution operator?
stop the leak by shutting down isolation valves
23
The chlorine concentration in a distribution system , once the chlorine demand has been met is called
Chlorine residual
24
In theory , what is the maximum suction lift of a centrifugal pump at sea level?
34 feet
25
Laboratory records for turbidity analysis should be kept for ______ years
Five
26
What type of meter is most commonly used for residential water metering
Positive displacement
27
The national primary drinking water regulations apply to contaminants that have an adverse effect on:
Human health
28
petroleum fuels, and other organic compounds may permeate which type of pipe
Plastic
29
If Coliform bacteria is found in a water supply. What is likely the source?
Fecal matter from warm, blooded animals
30
.
Arch style
31
What type of reservoir is constructed like a swimming pool?
Hydrauliclly applied concrete
32
What is the maximum hold time for a coliform sample? If you are sending it to an outside lab
30 hours
33
What happens to the disinfection effectiveness of Chlorine as water temperature decreases?
Less effective
34
What is the minimum flow velocity in Flushing a section of pipe?
2.5 FPS
35
after installing and pressure testing a new water main, what is the next thing I should be done
Disinfect it with a 25 mg/L to 50 mg/L chlorine solution for 24 hours
36
What is the recommended dose when Using the tablet method to disinfect a water main?
50 mg/l
37
The secondary standard for iron is
0.30 MGL
38
If the recharge area of a confined aquifer is elevated, what will happen to the water in The aquifer
It will be pressurized
39
How are sample locations for coliform sample selected
locations that are representative of the entire system
40
Which type of level sensor is connected to a pressure transducer with a tube
Diaphragm element
41
A water sample that is nearly identical to the content and consistency of a larger body of water is called
Representative sample
42
Cave in protection is required for all trenching operations deeper than ______ ft
5
43
What happens to the accuracy of a positive displacement meter over time?
It reads low
44
what is the main reason? Wells are sealed or grouted?
prevent surface water contamination
45
Which chemicals require an MSDS?
All chemicals used in the workplace
46
What type of meter is used to measure a wide range of flows?
compound meter
47
When installing shoring in a trench, how much space should be between each section
No space
48
Which type of curb box prevents misalignment
Minneapolis style
49
What is the minimum oxygen concentration for an environment to be considered safe?
19.5%
50
The depression of the water surface around the well caused by pumping is called the
Cone of depression
51
Why are booster pumps used in a distribution system?
Raise pressure to overcome an elevation difference
52
an entrant Going into a permit required confined space is required to wear
Chest or body harness, and a retrieval line
53
A chemical field pump used to dispense a chlorine solution into a water system is called
Hypochlorinator
54
What is the main purpose of distribution storage tanks?
Meat, peak water demands
55
when is the best time to conduct a leak survey?
When noise levels are lowest
56
A cleaning plug that has silicone carbide, wire brushes, or hardened steel brushes is called
scraping pig
57
Hey Dry barrel fire hydrant has
One main valve, the barrel from Water main pressure
58
Who is responsible for public notification if there is a water quality problem
The water system
59
What type of ductile iron pipe joint is the least expensive and goes together fast
Push on joint
60
which of the following will increase the corrosion rate when present in water ?
Dissolved oxygen
61
what is the health risk associated with trihalomethanes
cancer
62
A connection between a potable water system and non-potable water system is called a:
cross connection
63
what is the C value of a pipe a measure of?
The smoothness of a pipes interior wall
64
Distant locations should be monitored by what type of instrumentation
Relay systems
65
what is the difference between a primary and secondary standard?
primary standards are for substances believed to pose a health risk while secondary standards do not
66
Which sample requires the chlorine residual to be removed prior to analysis
Coliform bacteria
67
What is the recommended maximum distance between isolation valves?
800 feet
68
Why is it necessary to maintain system pressure above 20psi?
Prevent contamination
69
A measurement of the hydrogen ion concentration is called
PH
70
Before entering an enclosed tank to work, what paperwork should be completed?
Confined space permit
71
What type of storage tank is built in the way that resembles a home basement?
Cast place concrete
72
Why is it necessary to maintain a chlorine residual and the distribution system?
Contamination can occur at any time
73
The act passed by the US Congress in 1974 ensure safe, drinking water for consumers is called
Safe, drinking water act
74
what is the determining factor when designing the size and capacity of distribution system tanks pipes, and pumps
Fire protection needs
75
If a motor is started infrequently but needs to be brought up to speed quickly when it is started, what is the best type to use for the application
Capacitor start
76
What is the difference between a weak acid and a strong acid?
Amount of hydrogen ions released
77
When handling sodium hypochlorite, what type of protective gear should be worn?
Chemical goggles
78
chlorine demand is the difference between the chlorine _______ and the chlorine _______.
dose and residual
79
What is the maximum contaminant level goal for chloride?
250 mg/l
80
if your distribution system has an active flushing program, when is the best time to perform the flushing
During night or times of least traffic
81
What are two common metals used for Anodes?
Zinc and magnesium
82
What is one method of increasing your wells productivity?
Acidification