Welcome to the Water Treatment Operator 100 Question Practice Test.
Choose the best possible answer to the question.
1.
The fluoride injection point should be located after water has received complete treatment.
2.
Records of sanitary surveys must be kept for?
3.
What is the only MCL that varies with the temperature?
4.
At minimum, the Surface Water Treatment Rule requires surface water users to use what two treatment methods?
5.
Opening the discharge valve one full turn on a chlorine cylinder will?
6.
What is the next test when the membrane filter test shows four green colored colonies after incubating for 24hrs?
7.
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?
8.
What type of sedimentation basins have the flow of water admitted at an angle?
9.
What causes water to turn red?
10.
The size of Giardia in the trophozoite stage is approximately?
11.
What was created to have uniform standards in Water Treatment?
12.
The continuous circulation of water from the earth into the atmosphere and back again is called?
13.
What is the best type of salt to use in the regeneration of ion exchange softener resin?
14.
What laboratory device sterilizes laboratory apparatuses and microbial media by using pressurized steam?
15.
What chemical oxidant is most effective in reducing the concentration of taste and odor compounds caused by actinomycetes species?
16.
The porous material just above the water table that holds small quantities of water by capillary action is called?
17.
Viruses are sometimes resistant to disinfection.
18.
Gravity filters should not use more than what percent of daily production for backwash?
19.
What is the minimum angle that self cleaning tube settlers must be placed?
20.
It is important not to rinse out the sample bottes used for collecting samples for bacteriological examination because?
21.
What unit process will diatoms most likely replace?
22.
Free chlorine residual values are based on contact time of at least?
23.
What is the usual range of percent sludge solids, if the sludge is allowed to accumulate and compact at the bottom of a sedimentation basin?
24.
What TON will consumers start to notice?
25.
In the ion exchange softening process, once the resin can no longer soften water it must?
26.
If a water system collects less than 40 samples a month, how many can be coliform positive and the water system still maintain compliance?
27.
What process is considered to best to remove color from water in a conventional surface water treatment plant?
28.
The sampling points located for required sampling of natural radionuclides are located?
29.
The marble test is used to determine if water is saturated with calcium carbonate and has what other general use?
30.
What chemical is slacked lime?
31.
Filtration rates vary from what of filter surface area?
32.
The loss of chloramine residuals in a water line or a storage tank is due to?
33.
What type of algae would most likely be found in nutrient rich water?
34.
What could happen if the sludge in a sedimentation basin becomes too thick?
35.
How does Groundwater differ from Surface water sources?
36.
Radon is a radioactive decay daughter of radium 226.
37.
What is the most favorable raw water condition for good flocculation?
38.
A test(s) used to monitor the disinfection processes would be?
39.
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?
40.
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?
41.
Typically, how long is the flash mixing time in the coagulation process?
42.
When should polyphosphates used for sequestration of iron and manganese from a well be injected?
43.
An organic particle that is stabilized by attracting a layer of water molecules to its surface is known as a?
44.
Detention time in flocculation basins are usually designed to provide for?
45.
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?
46.
What is the optimal pH range for the removal of particulate matter when using Alum as a coagulant?
47.
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.
48.
Why is water softening a part of the water treatment process?
49.
A change in the water elevation from the normal level to the pumping level is?
50.
One ton chlorine containers are equipped with two valves, one for liquid and one for gas.
51.
Which is a chemical used in water treatment as a coagulating chemical?
52.
When 0.3 mg/L chlorine is added to water, the residual will increase by 0.3 mg/L.
53.
What is the purpose of body feed in the operation of a diatomaceous earth filter?
54.
What is the most important reason to reduce turbidity?
55.
What device found in labs sterilizes by using pressurized steam?
56.
What will cause reverse osmosis membranes to compact faster?
57.
What is the MCL for HAA5s?
58.
If there is gravel displacement in a filter bed from backwash rates with too high of a velocity, could eventually cause?
59.
Once they become fouled, how are reverse osmosis membranes cleaned?
60.
The more hydrogen ions
61.
What units ae the MCLs for radium-226, radium 228 and gross alpha particles radioactivity measured in?
62.
Where is sludge pumped when it is removed from a clarifier or after a filter backwash?
63.
Why do mud balls and hard spots develop in high rate gravity filters during the summer months?
64.
What are total dissolved minerals in rainwater typically close to?
65.
What oxidant has a potential of producing ClO3 by products?
66.
Backwashing rate procedures should be reassessed to determine the cause of granular activated carbon loss if?
67.
Which oxidant has the protentional of producing Chlorate (Cl03) by-products?
68.
The structure Diatomaceous Earth filters media is applied to is called?
69.
The most favorable condition in raw water for good flocculation with alum is?
70.
What angle should the parallel inclined plates be installed when using the shallow depth sedimentation method?
71.
How often should sedimentation basins with mechanical sludge removal equipment be drained and inspected?
72.
What does a low pH favor the formation of?
73.
What national law regulates underground disposal of wastes in deep wells?
74.
The minimum detention time in a conventional detention basin is?
75.
What is an inorganic particle that is stabilized in water by attracting a layer of oppositely charged ions surrounded by a diffuse layer of counterions?
77.
Under the Surface Water Treatment Rule a multiple barrier treatment consists of
78.
Solids contact basins have much shorter detention times than conventional treatment basins.
79.
What organism can escape coagulation and then pass through a granular filter?
80.
What is the removal level of cryptosporidium oocysts with conventional sedimentation?
81.
The outlet of a forced ventilation system for a chlorinator room she be located?
82.
The upper surface of the zone of saturation of ground water in an unconfined aquifer is called the?
83.
What part of the human body is the most vulnerable to allowing microorganisms to enter it?
84.
What determines whether or not colloidal sized particles in suspension repel each other, stay in suspension, or agglomerate and eventually settle?
85.
Community water systems must check the natural radioactivity in their water supply at least?
86.
What percentage of solids sludge is produced in the precipitative softening plant?
87.
Alachlor, Lindane, and Toxaphene are examples of?
88.
What is the most advantageous application point for powdered activated carbon?
89.
According to the AWWA, at 0.1 NTUs filtration can remove what percent of giardia cyts?
90.
What factor is used to express the relative volatility of a substance?
91.
The temperature range at which coliform bacteria samples must be stored before being delivered to a lab is?
93.
The chlorine demand with vary with?
94.
Which is the normal sequence of solids removal processing following flash mixing in a conventional water treatment plant?
95.
Backflow wash flows should expand filter media by?
96.
Determining the pH is an important water quality test because the results indicate?
97.
A system that fails to collect water samples in their distribution system would fall under which public notification system?
98.
What is the best process for sequestering manganese?
99.
What is the MCL for THM's?
100.
What is the best disinfectant against Cryptosporidium?
