Welcome to the Water Treatment Operator 100 Question Practice Test.
Choose the best possible answer to the question.
1.
A coliform sample is considered invalid and a new sample must be taken within 24hrs if the HPC count is above?
2.
What disinfectant is commonly used and free of Cl2 to avoid THMs?
3.
What is usually used to disinfect the gravel packing of a ground water well?
4.
The process by which water becomes a gas and rises is called?
5.
What conditions will +Eh values of water support?
6.
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?
7.
What chemical may encourage growth of algae and microorganisms?
8.
The upper surface of the zone of saturation of ground water in an unconfined aquifer is called the?
9.
Why is it important to reduce turbidity?
10.
Evaporated water in the earth's atmosphere will condense to form
11.
For alum coagulation of color, what is the correct pH?
12.
The organism that causes Giardiasis
13.
What is the most important thing to consider in automatic startup after a power failure has occured?
14.
When soda ash is added to water for softening purposes what will it do?
15.
The release of dissolved gasses in saturated cold water when pressure decreases in filter beds causes?
16.
What changes does an operator need to make when there are issues with floc formation?
17.
Never apply water to a gaseous chlorine leak because the water will cause more issues.
18.
What zone in a lake or reservoir has weeds that grow underwater that may cause taste & odor complaints?
19.
What should the an above ground raw water source be tested for if a water plant gets its water from a river that is subject to a cattle feed lot where water runs off?
20.
What percentage of solids sludge is produced in the precipitative softening plant?
21.
What is the rule that sets MCL's for harmful chemicals?
22.
What causes an increase in taste and odors when natural waters lack DO?
24.
What laboratory device sterilizes laboratory apparatuses and microbial media by using pressurized steam?
25.
What is the process that is used to concentrate sludge?
26.
What chemical could cause pink water problems?
27.
Why do mud balls and hard spots develop in high rate gravity filters during the summer months?
28.
A property that is important to water treatment that is physical as opposed to chemical is?
29.
Low temperature water can be compensated for when using Alum by?
30.
Where does most of the carbon dioxide in groundwater originate from?
31.
What membrane process is used to treat brackish water or seawater?
32.
What percentage of the earth's surface is covered in water?
33.
What type of algae would most likely be found in nutrient rich water?
34.
Which is the best removal method if a well contains soluble iron?
35.
A composite sample should never be collected for what type of analysis?
36.
What is the most effective method for the removal of disinfection by products?
37.
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?
38.
Why is water softening a part of the water treatment process?
39.
What is the most favorable raw water condition for good flocculation?
40.
The hour during the day when the largest volume of water is being pumped is known as peak hourly flow?
41.
Community and non-transient community water systems must test for what if they use ozone for disinfection of oxidation?
42.
What forms when you add Alum to turbid water?
43.
The disinfection treatment process is?
44.
A connection between a potable water system and a non potable water system is?
45.
As the level of phosphates increase in a new water supply, an operator should?
46.
Which is not considered to be a waterborne disease?
47.
The more hydroxide ions
48.
What percentage of the air is usually converted to ozone if air is used to generate ozone?
49.
The action level for copper is 0.015 mg/L.
50.
What angle should the parallel inclined plates be installed when using the shallow depth sedimentation method?
51.
What is dental fluorosis?
52.
What TON will consumers start to notice?
53.
The fluoride injection point should be located after water has received complete treatment.
54.
In alum sludge, what is typically the percentage of solid material?
55.
What parameter must be much better than conventional treatment basins in basins using tube and plate settlers?
56.
Powered activated carbon is usually used to control what?
57.
For lime-soda ash softening plants, what is the most economical sludge disposal method?
58.
The scattering of light by the particles in finished water is from the turbidity caused by
59.
Why are polyphosphates used in drinking water?
60.
Which of the following composes the majority of scale in pipes?
61.
An organic particle that is stabilized by attracting a layer of water molecules to its surface is known as a?
62.
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?
63.
Which is the method for testing for total coliform bacteria?
64.
What will neutralize chlorine?
65.
What should be determined first before an in ground sedimentation tank is drained?
66.
Alachlor, Lindane, and Toxaphene are examples of?
67.
According to the Surface Water Treatment Rule, multiple barrier treatment is defined as?
68.
A water molecule is made up of ?
69.
If the chlorine demand suddenly increases from 0.4 mg/L to 2.8 mg/L, what could be the reason?
70.
Once they become fouled, how are reverse osmosis membranes cleaned?
71.
At minimum, the Surface Water Treatment Rule requires surface water users to use what two treatment methods?
72.
The process of the build up of corrosion products is known as?
73.
What form is the protozoan Giardia Lamblia transmitted in?
74.
How many colonies per mI must the HPC test results show to be considered a reliable sample for coliform bacteria?
75.
What is the main function of a flocculation basin?
76.
If dry alum and quicklime are mixed together, what will happen?
77.
With coagulation reactions when alum is used, the specific insoluble floc formed is a precipitate of?
78.
Plant growth in a reservoir will usually be found at a depth of?
79.
Viruses are sometimes resistant to disinfection.
80.
A water sample that is acidified must have a final water pH of?
81.
Under the Surface Water Treatment Rule a multiple barrier treatment consists of
82.
Which of these has the most impact on tastes and odors in water?
83.
Salts, Bases, and Acids lacking carbon are organic compounds.
84.
A common chemical added to boost alkalinity is?
85.
Nitrification in the distribution system can best be described as?
86.
What will ion exchange remove?
87.
What is calcium sulfate also known as?
88.
What is the only MCL that varies with the temperature?
89.
When responding to a chlorine gas leak, the responder should have a SCBA and a?
90.
At its endpoint, what color does the oxidant potassium permanganate turn?
91.
A chlorine evaporator maintains a water bath at?
92.
What is a universal solvent?
93.
What would be best to use for corrosion inhibition if the water is very low in alkalinity and calcium concentration?
94.
Anaerobic conditions in reservoirs can cause what problem?
95.
When entering a permitted confined space entry structure, always complete a permit and?
96.
Water hardness is measured in equivalent amounts of?
97.
Current regulations require that water treatment wastes be monitored?
98.
What precipitates can foul a cation exchange resin?
99.
Settled backwash water that is recovered and re-used from a conventional surface water filtration plant should be returned to the beginning of the treatment train.
100.
What is true about heterotrophic bacteria?
