Welcome to the Water Treatment Operator 100 Question Practice Test.
Choose the best possible answer to the question.
1.
Which of the following composes the majority of scale in pipes?
2.
When soda ash is added to water for softening purposes what will it do?
3.
What is a hypochlorinator used for?
4.
A composite sample should never be collected for what type of analysis?
5.
What is the typical strength of calcium hypochlorite?
6.
The maximum safe level of electrical current that will not have any long lasting health effects is?
7.
What tests are performed most frequently in drinking water systems?
8.
When disinfecting a well with free chlorine, what is the required exposure time and what must the concentration be?
9.
Fine solids that remain suspended in water and will not settle on their own are known as?
10.
A test(s) used to monitor the disinfection processes would be?
11.
What is the most effective disinfection residual?
12.
Microorganisms that require dissolved or free oxygen are?
13.
The structure Diatomaceous Earth filters media is applied to is called?
14.
If there is gravel displacement in a filter bed from backwash rates with too high of a velocity, could eventually cause?
15.
When the cell division in bacteria has been disrupted, it has been?
16.
What are the precursors to THMs?
17.
When treating surface water, the main reason for removing solids is?
18.
What factor is used to express the relative volatility of a substance?
19.
The chemical combination for substances in solution so as to cause separation in the insoluble form can be described as?
20.
Never install a new gasket when a chlorine cylinder or container is changed.
21.
One ton chlorine containers are equipped with two valves, one for liquid and one for gas.
22.
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.
23.
If dry alum and quicklime are mixed together, what will happen?
24.
When 0.3 mg/L chlorine is added to water, the residual will increase by 0.3 mg/L.
25.
The more hydroxide ions
26.
To unclog the head of a chemical feed pump an operator should first?
27.
If the natural fluoride content of raw water is variable, the concentration of the raw water should be measured?
28.
Low temperature water can be compensated for when using Alum by?
29.
When doing coliform analysis use the presence-absence method, a sample should be incubated for?
30.
In pounds, how much ammonia is contained in a 1 ton cylinder that is full?
31.
Determining the pH is an important water quality test because the results indicate?
32.
Backwashing rate procedures should be reassessed to determine the cause of granular activated carbon loss if?
33.
One of the ways an optimum coagulant dosage can be established is?
34.
What is the most probable solution if nematodes are interfering with the disinfectant?
35.
Acid rain is caused by
36.
Why are polyphosphates used in drinking water?
37.
Water hardness is measured in equivalent amounts of?
38.
What membrane process is used to treat brackish water or seawater?
39.
What conditions in a gravity filter will be produced when there is a larger particle size and less dense anthracite media?
40.
Opening the discharge valve one full turn on a chlorine cylinder will?
41.
When it is dissolved in water for disinfection purposes, how long does ozone last?
42.
What units ae the MCLs for radium-226, radium 228 and gross alpha particles radioactivity measured in?
43.
The process by which water becomes a gas and rises is called?
44.
Adding CO2 to water will?
45.
What is the best probable solution if rotifers are visible in finished water?
46.
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?
47.
What are the chemical symbols for hypochlorous acid and hypochlorite ions?
48.
What are the hair like appendages that Giardia trophozoites use to propel themselves through water are?
49.
What laboratory device sterilizes laboratory apparatuses and microbial media by using pressurized steam?
50.
What is the total concentration of dissolved solids in the wastewater from the regeneration of ion exchange units?
51.
Where are the two points on a gravity filter used to measure head loss located?
52.
Assuming all other variables remain the same, a decrease in the pH when using free chlorine would?
53.
In a saturator tank for flows of less than 100 gpm, how thick should the layer be maintained of sodium fluoride crystals?
54.
If ammonia vapor is passed over a chlorine leak in a cylinder valve, the leak is indicate by
55.
What will cause reverse osmosis membranes to compact faster?
56.
What is the best process for removing turbidity?
57.
What TON will consumers start to notice?
58.
Why has magnetic ion exchange resin been developed?
59.
When a raw water analysis shows the presence of anabaena, ceratium and oscillatoria, what problem may arise?
60.
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?
61.
What test is used to determine the presence of coliform bacteria?
62.
What adverse effects does the secondary contaminant manganese have?
63.
What is a similar process to reverse osmosis that uses lower pressures without removing all mineral content?
64.
What chemical oxidant would be best for controlling the forming of THMs?
65.
What is the simplest chlorine gas feeder for controlling chlorine gas flow?
66.
Detention time in flocculation basins are usually designed to provide for?
67.
According to the Surface Water Treatment Rule, multiple barrier treatment is defined as?
68.
Records of sanitary surveys must be kept for?
69.
Improper backwashing of the filter media can lead to?
70.
Waterborne diseases like typhoid and cholera are caused by?
71.
Sludge should be removed from a gravity sedimentation basin when reaching a level of?
72.
What causes an increase in taste and odors when natural waters lack DO?
73.
The chlorine demand with vary with?
74.
What oxidant should be fed as early as possible in the treatment process to allow for complete reaction before it enters the distribution system?
75.
What is the purpose of body feed in the operation of a diatomaceous earth filter?
76.
What percentage of solids sludge is produced in the precipitative softening plant?
77.
What water rights are acquired from diverting a water source and then putting it to beneficial use?
78.
What form is Giardia most infectious?
79.
During filtration, what role does the action of straining of suspended particles play?
80.
What type of filtration is permitted under the Surface Water Treatment Rule?
81.
What type of water violation requires an all clear notification be given to the public?
82.
The fusible metal plugs on chlorine containers are designed to melt at what temperatures?
83.
The loss of chloramine residuals in a water line or a storage tank is due to?
84.
What organism is associated with taste and odors?
85.
What oxidant has a potential of producing ClO3 by products?
86.
The proper emergency kit for a chlorine tanker is?
87.
What does the pulsating energy in a pulsator clarifier help to do?
88.
What disinfectant is commonly used and free of Cl2 to avoid THMs?
89.
What is the MCLG for chloride?
90.
Daily flow rates are limited in a conventional treatment plant due to the detention time needed to settle the floc and its sedimentation basin. What is the time range for the clarifier?
91.
What can immediately occur if newly installed manganese greensand was not skimmed of the fines after backwashing and stratification steps were completed?
92.
The IDLH (immediately dangerous to life and health) value for chlorine is?
93.
What process change be should be done if the level of turbidity in raw water decreased from 7 to 3 NTUs?
94.
What does it mean when a filter is ripening?
95.
If the chlorine demand suddenly increases from 0.4 mg/L to 2.8 mg/L, what could be the reason?
98.
What is dissolved air flotation good for removing?
99.
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?
100.
All chlorine gas rooms...
