Welcome to the Water Treatment Operator 100 Question Practice Test.
Choose the best possible answer to the question.
1.
If a water system collects less than 40 samples a month, how many can be coliform positive and the water system still maintain compliance?
2.
Even a low concentration of ammonia gas can be fatal to humans if it is at least?
3.
Why is it important to reduce turbidity?
4.
What is a physical separation between a water supply outlet and the flood-level rim of a receiving vessel that must be at least twice the diameter of the water supply outlet and the flood-level rim of the receiving vessel. This separation must be at leasttwice the diameter of the water supply outlet and never less than one inch?
5.
What is the MCL for THM's?
6.
What is the motion called for the particles in water that are in constant motion and work in conjunction with the destabilization process to create floc?
7.
Powered activated carbon is usually used to control what?
8.
The hydrologic cycles create what two primary sources of water?
9.
When pumping from Well #1 the static level of Well #2 drops. What causes this?
10.
To unclog the head of a chemical feed pump an operator should first?
11.
What is the total concentration of dissolved solids in the wastewater from the regeneration of ion exchange units?
12.
The cl2 residual in water may be determined by using the reagent?
13.
What is the most efficient process for the removal of nitrate and nitrate?
14.
What effect will caustic soda (NaOH)have on water?
15.
What is dental fluorosis?
16.
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?
17.
Where does most of the carbon dioxide in groundwater originate from?
18.
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?
19.
According to the Surface Water Treatment Rule, multiple barrier treatment is defined as?
20.
If a body of water has high salinity and is warm, it will generally be high in dissolved oxygen.
21.
At its endpoint, what color does the oxidant potassium permanganate turn?
22.
What is the most probable solution if nematodes are interfering with the disinfectant?
23.
Which is the normal sequence of solids removal processing following flash mixing in a conventional water treatment plant?
24.
Microorganisms that require dissolved or free oxygen are?
25.
What zone in a lake or reservoir has weeds that grow underwater that may cause taste & odor complaints?
26.
What factor is used to express the relative volatility of a substance?
27.
Granular activated carbon is used as?
28.
Current regulations require that water treatment wastes be monitored?
29.
For maximum charge neutralization the average zeta potential should be in what range?
30.
What part of the human body is the most vulnerable to allowing microorganisms to enter it?
31.
Coagulation occurs during the first
33.
What does the saturation point of calcium carbonate primarily depend on?
34.
What is the primary drawback for facilities that use ultra violet light to disinfect water?
35.
When sludge is produced by water drawn from sources with relatively low turbidity it can be?
36.
When must a water system collect annual samples if the water system has been determined to be reliable by the State and consistently below the MCL level for organic compounds?
37.
Past the breakpoint chlorination point, what percentage of the total chlorine residual should be free chlorine?
38.
What would be the short term goal when a water source is destroyed or damaged by some type of disaster that causes total contamination?
39.
What is the removal level of cryptosporidium oocysts with conventional sedimentation?
40.
Improper backwashing of the filter media can lead to?
41.
Never apply water to a gaseous chlorine leak because the water will cause more issues.
42.
Which is the best removal method if a well contains soluble iron?
43.
The outlet of a forced ventilation system for a chlorinator room she be located?
44.
What parameter must be much better than conventional treatment basins in basins using tube and plate settlers?
45.
Why has magnetic ion exchange resin been developed?
46.
How often should the solids concentration be determined in solid contact basins with fairly constant water quality parameters?
47.
If adequate surface area and detention time is provided in the sedimentation basin, what would the expected solids removal efficiency level be?
48.
What happens when there is high algae growth in a reservoir?
49.
Which is a chemical used in water treatment as a coagulating chemical?
50.
During filtration, what role does the action of straining of suspended particles play?
51.
Reservoir turnover events cause by temperature changes reduce what at deeper water levels?
52.
Free chlorine residual values are based on contact time of at least?
53.
What process would be most effective for the destruction of heterotrophic bacteria?
54.
What conditions will +Eh values of water support?
55.
What is the best type of salt to use in the regeneration of ion exchange softener resin?
56.
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?
57.
What unit process will diatoms most likely replace?
58.
What is the most effective disinfection residual?
59.
How much does water expand by when it freezes compared to its original value?
60.
What oxidant should be fed as early as possible in the treatment process to allow for complete reaction before it enters the distribution system?
61.
What units ae the MCLs for radium-226, radium 228 and gross alpha particles radioactivity measured in?
62.
Adding CO2 to water will?
63.
What are the chemical symbols for hypochlorous acid and hypochlorite ions?
64.
During daylight hours, algae growth in a reservoir will do what?
65.
Backwashing rate procedures should be reassessed to determine the cause of granular activated carbon loss if?
66.
How often should the fluoride feed system be checked?
67.
What is the filtration flow rate through a manganese greensand pressure filter at 10 degrees Celsius?
68.
When doing coliform analysis use the presence-absence method, a sample should be incubated for?
69.
Pulsator clarifiers are used to?
70.
In which state are Giardia most vulnerable to inactivation through disinfection?
71.
Typically, how long is the flash mixing time in the coagulation process?
72.
Anaerobic conditions in reservoirs can cause what problem?
73.
What is the MCL for HAA5s?
74.
What water quality indicator is of greatest concern in a surface water treatment plant?
75.
The Surface Water Treatment Rule states that multibarrier treatment must result in the inactivation of Giardia cysts and viruses by?
76.
Which is the method for testing for total coliform bacteria?
77.
What is the most important reason to reduce turbidity?
78.
Shellfish grown in polluted waters have been known to contain the organism that causes infectious hepatitis.
79.
Pure water can be found?
80.
In a permit entry confined space, who is responsible for terminating entries?
81.
What does not pose a threat to human health in the drinking water?
82.
What chemical is slacked lime?
83.
What water quality indicator should be considered in a lake de-stratification program?
84.
What would have the least impact on the efficiency of copper sulfate?
85.
If ammonia vapor is passed over a chlorine leak in a cylinder valve, the leak is indicate by
86.
What is used to prevent water from entering a gas chlorinator?
87.
In pounds, how much ammonia is contained in a 1 ton cylinder that is full?
88.
It is important not to rinse out the sample bottes used for collecting samples for bacteriological examination because?
89.
What percentage of the earth's surface is covered in water?
90.
Post sedimentation process, the turbidity of settled water before it is applied to the filters should be kept below?
91.
What chemical can be added to the water system to sequester Iron and Manganese?
92.
What is the optimal pH range for the removal of particulate matter when using Alum as a coagulant?
93.
What is a major cause of short circuiting in a sedimentation basin?
95.
The most accurate chlorine residual measurement would be taken with?
96.
If sodium hypochlorite comes into contact with the skin or eyes, the area should be flushed with water for at least 15 minutes.
97.
If dry alum and quicklime are mixed together, what will happen?
98.
Alachlor, Lindane, and Toxaphene are examples of?
99.
The action level for copper is 0.015 mg/L.
100.
Ion exchange processes can typically be used for direct groundwater treatment as long as turbidity and what else have levels that are not excessive?
