Welcome to the Water Treatment Operator 100 Question Practice Test.
Choose the best possible answer to the question.
1.
What effect will an increase in total dissolved solids in water to be treated be?
2.
Plant growth in a reservoir will usually be found at a depth of?
3.
The scattering of light by the particles in finished water is from the turbidity caused by
4.
If there is a notification of a HazMat spill of an unknown chemical into a stream that provides water to a water treatment plant, what would be the best action taken?
5.
The maximum safe level of electrical current that will not have any long lasting health effects is?
6.
What device found in labs sterilizes by using pressurized steam?
7.
Which of the following are true. At the end of the coagulation, flocculation, and sedimentation process?
8.
What percentage of solids sludge is produced in the precipitative softening plant?
9.
Which natural electrical force keeps colloidal particles apart in water treatment?
10.
What parameter must be much better than conventional treatment basins in basins using tube and plate settlers?
11.
What does it mean when a filter is ripening?
12.
What conditions in a gravity filter will be produced when there is a larger particle size and less dense anthracite media?
13.
During daylight hours, algae growth in a reservoir will do what?
14.
The Colilert test (ONPG-MUG) shows the presence of total coliforms is shown by?
15.
For lime-soda ash softening plants, what is the most economical sludge disposal method?
16.
If a water system collects less than 40 samples a month, how many can be coliform positive and the water system still maintain compliance?
17.
What do long filter runs tend to cause?
18.
Pure water can be found?
19.
Compared to disinfecting water with free chlorine, what is a disadvantage in switching to ozone?
20.
Typically, how long is the flash mixing time in the coagulation process?
21.
What will neutralize chlorine?
22.
What is the filtration flow rate through a manganese greensand pressure filter at 10 degrees Celsius?
23.
What are the precursors to THMs?
24.
Which is not considered to be a waterborne disease?
25.
Which of the following composes the majority of scale in pipes?
26.
The pH scale ranges from?
27.
What is the main problem if particle agglomeration is occurring in a filter for iron and manganese removal at the interface of the coal layer below?
28.
For maximum charge neutralization the average zeta potential should be in what range?
29.
A chlorine evaporator maintains a water bath at?
30.
What is the simplest chlorine gas feeder for controlling chlorine gas flow?
31.
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?
32.
If a body of water has high salinity and is warm, it will generally be high in dissolved oxygen.
33.
Notification to the public of a Tier III violation is done
34.
Which is classified as a secondary contaminant?
35.
Detention time in flocculation basins are usually designed to provide for?
36.
What is the optimal pH range for the removal of particulate matter when using Alum as a coagulant?
37.
How much carbon is approximately lost during the reactivation process for granular activated carbon?
38.
What does total alkalinity refer to?
39.
When responding to a chlorine gas leak, the responder should have a SCBA and a?
40.
To unclog the head of a chemical feed pump an operator should first?
41.
If a filter is operating at a normal flow rate, its ability to trap flocculated particles is suspension is a function of?
42.
What is the pH range of sodium hypochlorite?
43.
Coagulation is a chemical and physical reaction that converts?
44.
What are different types of media used to filter water for human consumption?
45.
Filtration rates vary from what of filter surface area?
46.
Impurities that do not dissolve in water and settle out eventually are?
47.
Which would be an indication that there is an issue with a part of the coagulation-flash mix-flocculation process operation?
48.
A surface water treatment plant should have at least how many filtration beds?
49.
A test(s) used to monitor the disinfection processes would be?
50.
What is the best addition for water that is highly colored due to organic matter?
51.
What is the most important thing to consider in automatic startup after a power failure has occured?
52.
What chemical oxidant is most effective in reducing the concentration of taste and odor compounds caused by actinomycetes species?
53.
If the natural fluoride content of raw water is variable, the concentration of the raw water should be measured?
54.
When using the lime soda ash process, it is impossible to produce water with a hardness of less than?
55.
What should an operator do to compensate for temperature changes in a conventional water treatment plant with dual media filters that has very cold water in the winter and warm water in the summer?
56.
Operators working at a treatment plant should only use self contained breathing apparatus equipment that has been approved by what agency?
57.
Nitrification in the distribution system can best be described as?
58.
What is the most important reason to reduce turbidity?
59.
What disinfectant is commonly used and free of Cl2 to avoid THMs?
60.
The hour during the day when the largest volume of water is being pumped is known as peak hourly flow?
61.
A total coliform positive sample must be tested for the presence of?
62.
Never install a new gasket when a chlorine cylinder or container is changed.
63.
In a permit entry confined space, who is responsible for terminating entries?
64.
What causes water to turn red?
65.
The Zeta Protentional measures the number of excess what found on the surface of all particular matter?
66.
After a backwash, to avoid turbidity spikes at the start of a service run, filters should be equipped with?
67.
What will cause reverse osmosis membranes to compact faster?
68.
Pathogenic organisms?
69.
How does Groundwater differ from Surface water sources?
70.
In a saturator tank for flows of less than 100 gpm, how thick should the layer be maintained of sodium fluoride crystals?
71.
One of the steps taken to determine the threshold odor number is?
72.
What process would be most effective for the destruction of heterotrophic bacteria?
73.
Alachlor, Lindane, and Toxaphene are examples of?
74.
What method can be used to control scaling, but is never used to control corrosion?
75.
What conventional treatment step is eliminated by direct filtration?
76.
What chemical may encourage growth of algae and microorganisms?
77.
During filtration, what role does the action of straining of suspended particles play?
78.
The size of Giardia in the trophozoite stage is approximately?
79.
When treating surface water, the main reason for removing solids is?
80.
What is the best type of salt to use in the regeneration of ion exchange softener resin?
81.
Why is it important to reduce turbidity?
82.
When abundant in water, what algae genera are most likely to cause taste and odor issues when abundant in water?
83.
Granular activated carbon is used as?
84.
What is recarbonation?
85.
What type of charge do the compounds that form when iron or aluminum salts react with water have?
86.
In which state are Giardia most vulnerable to inactivation through disinfection?
87.
What are the hair like appendages that Giardia trophozoites use to propel themselves through water are?
88.
Most totalizer meters at treatment plants are commonly
89.
Ozone contractors must have a system to collect ozone off-gas because?
90.
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?
91.
What agency should be called for actual hands on assistance if a substantial chlorine leak incident occurs?
92.
What does pinpoint floc, fish eyes, and high turbidity in settled water indicate?
93.
What is the quantity of dissolved oxygen in water a function of?
94.
Where is sludge pumped when it is removed from a clarifier or after a filter backwash?
95.
In order to prevent air binding in a rapid sand filter, head loss should never exceed?
96.
What is the most probable solution if nematodes are interfering with the disinfectant?
97.
River water is not uniform in quality from hour to hour or day to day.
98.
What is the principle form of alkalinity found in raw water from both surface and ground sources?
99.
What is the next test when the membrane filter test shows four green colored colonies after incubating for 24hrs?
100.
If iron bacteria is causing corrosion problems in the filters, what is the best solution?
