Welcome to the Water Treatment Operator 100 Question Practice Test.
Choose the best possible answer to the question.
1.
In order to prevent air binding in a rapid sand filter, head loss should never exceed?
2.
Pure water can be found?
3.
Anionic polymers are used as filter aids to agglomerate small floc particles left in the sedimentation basin effluent and make them tougher to avoid?
4.
What type of sedimentation basins have the flow of water admitted at an angle?
5.
What occurs in raw water as the level of ammonia decreases?
6.
What is the only MCL that varies with the temperature?
7.
The maximum sustained flow possible from a well mostly depends on?
8.
What is the best addition for water that is highly colored due to organic matter?
9.
What is the maximum feed rate when adding fluoride to drinking water?
10.
If iron bacteria is causing corrosion problems in the filters, what is the best solution?
11.
When sludge is produced by water drawn from sources with relatively low turbidity it can be?
12.
What is the MCL for HAA5s?
13.
What sludge dewatering process is best for alum sludges when the cakes are very dry, filtrate is clear, and solids capture is very high?
14.
What water rights are acquired from diverting a water source and then putting it to beneficial use?
15.
What oxidant should be fed as early as possible in the treatment process to allow for complete reaction before it enters the distribution system?
16.
Floc is produced when there is a chemical reaction between the coagulant and alkalinity. If the alkalinity of raw water is too low the floc formation will be poor. Some form of alkalinity must be added if the amount that is naturally found in the water source is less than?
17.
Which process helps remove contaminants in water by causing them to cling to the surface of certain filter grains?
19.
The most favorable condition in raw water for good flocculation with alum is?
20.
If the natural fluoride content of raw water is variable, the concentration of the raw water should be measured?
21.
The release of dissolved gasses in saturated cold water when pressure decreases in filter beds causes?
22.
What was created to have uniform standards in Water Treatment?
23.
Pathogenic organisms?
24.
The Surface Water Treatment Rule states that multibarrier treatment must result in the inactivation of Giardia cysts and viruses by?
25.
What causes an increase in taste and odors when natural waters lack DO?
26.
Wet activated carbon will remove what from the air? (In regards to safety)
27.
If a rapid gravity filter is well operated, the finished water will have?
28.
What type of chlorine gas feeder is most commonly used?
29.
What does not pose a threat to human health in the drinking water?
30.
In what form is Iron soluble in water?
31.
Radon is a radioactive decay daughter of radium 226.
32.
In the ion exchange softening process, once the resin can no longer soften water it must?
33.
What national law regulates underground disposal of wastes in deep wells?
34.
What method can be used to control scaling, but is never used to control corrosion?
35.
According to the AWWA, the time period a filter should be used and then replaced is?
36.
What factor is used to express the relative volatility of a substance?
37.
An autoclave will sterilize at
38.
For alum coagulation of color, what is the correct pH?
39.
What process would be most effective for the destruction of heterotrophic bacteria?
40.
HPC and Coliform tests are the same because they both?
41.
What will increase alkalinity, pH, and hardness?
42.
What laboratory device sterilizes laboratory apparatuses and microbial media by using pressurized steam?
43.
The advantage of using oxidant ozone is that it?
44.
A method to increase or maintain the DO concentration of a thermally stratified reservoir?
45.
Under the process of safety management, sites are required to do a site assessment if the facility in a single process has more than how many pounds of chlorine?
46.
Protozoa are larger than bacteria which are larger than viruses.
47.
When 0.3 mg/L chlorine is added to water, the residual will increase by 0.3 mg/L.
48.
Assuming all other variables remain the same, a decrease in the pH when using free chlorine would?
49.
The size of Giardia in the trophozoite stage is approximately?
50.
The action level for copper is 0.015 mg/L.
52.
Why are check valves installed in suction lines?
53.
At minimum, the Surface Water Treatment Rule requires surface water users to use what two treatment methods?
54.
A composite sample should never be collected for what type of analysis?
55.
Direct filtration eliminates what conventional treatment step?
56.
What is measured to determine total alkalinity?
57.
The outlet of a forced ventilation system for a chlorinator room she be located?
58.
One criteria to avoid filtration is that the fecal coliform concentration must be equal to or less than how many mg/L in representative samples of the source water immediately before the first or only point of disinfectant application in at least what percentage of the measurements made for the previous 6 months that the system served water to the public on an ongoing basis.
59.
A common chemical added to boost alkalinity is?
60.
The Zeta Protentional measures the number of excess what found on the surface of all particular matter?
61.
Fluoride concentration above what mg/L will likely cause teeth to become pitted?
62.
The type of filter that provides the lowest flow per square foot of surface are is?
63.
What water quality indicator is of greatest concern in a surface water treatment plant?
64.
If the continuous monitoring of the residual disinfectant concentration of the water entering the water system fails, how often will an operator need to collect a grab sample until the problem is fixed?
65.
The fusible metal plugs on chlorine containers are designed to melt at what temperatures?
66.
What type of self-contained breathing apparatus should be used at water plants?
67.
What is the filtration flow rate through a manganese greensand pressure filter at 10 degrees Celsius?
68.
An artesian spring occurs when
69.
Water treatment chemicals are added based on?
70.
What is the main function of a flocculation basin?
71.
How often should the solids concentration be determined in solid contact basins with fairly constant water quality parameters?
72.
What is the best probable solution if rotifers are visible in finished water?
73.
What membrane process is used to treat brackish water or seawater?
74.
What is used as part of a sedimentation basin to allow a controlled flow of the supernatant to be collected and directed to the filter beds?
75.
If a body of water has high salinity and is warm, it will generally be high in dissolved oxygen.
76.
For surface water systems without filtration, the Surface Water Treatment Rule requires public water systems to
77.
What angle should the parallel inclined plates be installed when using the shallow depth sedimentation method?
78.
What chemical oxidant would be best for controlling the forming of THMs?
79.
What effect will an increase in total dissolved solids in water to be treated be?
80.
Water that is softened has a high pH and a high concentration of CaCO3. Therefore stabilization is essential in order to prevent the CaCO3 from precipitating out on?
81.
During daylight hours, algae growth in a reservoir will do what?
82.
A method of destabilization is reducing the zeta potential to allow floc formation. What would be an acceptable ZP range?
83.
One of the ways an optimum coagulant dosage can be established is?
84.
What does a high pH favor the formation of?
85.
What is dental fluorosis?
86.
What are the precursors to THMs?
87.
The IDLH (immediately dangerous to life and health) value for chlorine is?
88.
What changes does an operator need to make when there are issues with floc formation?
89.
Where do Enteropathogenic organisms in water supplies originate?
90.
What would have the least impact on the efficiency of copper sulfate?
91.
What parameter must be much better than conventional treatment basins in basins using tube and plate settlers?
92.
If the water temperature decreases this will cause the disinfection action of chlorine to?
93.
What is usually used to disinfect the gravel packing of a ground water well?
94.
What chemical oxidant would be most effective for controlling biological growth?
95.
A test(s) used to monitor the disinfection processes would be?
97.
A pro of chloramines is?
98.
Water impurities that come from plants or animals are
99.
What is the natural attraction between particles that can be used to collect them into larger groups once destabilization has occurred?
100.
The hydrologic cycles create what two primary sources of water?
