Welcome to the 50 Question Water Distribution Practice Test.
Choose the best possible answer to the question.
1.
If an operator has a problem achieving adequate disinfection, a possible cause is?
2.
What corrosion inhibitor is most effective in control of lead in a distribution system?
3.
What is the National Primary Drinking Water Regulations MCL for total Hexavalent Chromium (Chromium 6)
4.
What is lake stratification?
5.
What percentage of the earth's surface is covered in water?
6.
If a bac-T sample is positive, repeat samples must be taken
7.
What is the MCL for THM's?
8.
Taste and odor complaints in the water system can be caused by?
9.
When a bac-T sample is positive, repeat samples must be taken
10.
The disinfection action of chlorine as the water temperature increases will what?
11.
What is a measure of a materials opposition to the flow of electric current?
12.
A portable ladder must extend how many feet above the upper surface of an excavated trench?
13.
The fluoride concentration in drinking water is set in relation to?
14.
Yellow hydrant body with a green cap signals?
15.
An autoclave will sterilize at
16.
What is the purpose of sodium thiosulfate in a water sample bottle?
17.
What type of oil should not be used to lubricate bearings because it forms acids as it begins to break down?
18.
Records of turbidity analysis must be kept for at least?
19.
Why is it important to monitor the speed of a variable speed pump?
20.
Why do insulators usually fail?
21.
What is the maximum contaminant level goal (MCLG) for a known or suspected carcinogen?
22.
If special bedding is required due to poor local soil conditions, the material should not contain granular material greater than?
23.
Mechanical seals are most appropriate for pumps operating under what condition?
24.
The lowest pressure point in a pump is?
25.
Water filters in the water treatment processes are primarily used for removing or reducing?
26.
If a water system collects less than 40 samples a month, how many can be coliform positive and the water system still maintain compliance?
27.
What is a prescriptive water right?
28.
What can be done to prevent cavitation form occurring?
29.
What is atmospheric pressure at sea level?
30.
What is the typical strength of calcium hypochlorite?
31.
What type of water main pipe has the highest maximum working pressure?
32.
Push joints can be used if the pipe must be pushed at an angle?
33.
An illness in infants known as methemoglobinemia, or blue baby syndrome, is attributed to?
34.
What is the MCLG for coliform bacteria?
35.
According to the Surface Water Treatment Rule, water systems serving a population of more than 500 persons must sample the filtered water for turbidity every?
36.
What tier violation has the most critical impact on human health and notification is immediate?
37.
The total dynamic head at which a pump must operate at is the sum of the static head and the head due to friction loss.
38.
The powder substance in a Bac-T sample bottle is?
39.
When disinfecting water mains with tablets what should the concentration be and for how long?
40.
If there is a large crack in a water main and the pressure in the distribution system drops to 0 psi, what may occur?
42.
What type of pipe joint lacks flexibility and is not normally burried?
43.
Mechanical seals on a centrifugal pump?
44.
What can be used to control scaling, but can never be used to control corrosion?
45.
What determines the minimum number of bacteriological samples that must be collected in a water distribution system?
46.
When gas chlorinators operate at a high rate of withdrawal, what may happen?
47.
What device found in labs sterilizes by using pressurized steam?
48.
What organisms have the greatest resistance to chlorine?
49.
The type of water main pipe most appropriate for river crossings and rugged terrain is?
50.
Velocity of flow in water mains is usually expressed in?
