Practice Questions Flashcards
1
Q
Which of the following is removed at raw water intake?
A
Fish and debris
2
Q
Which if the following is more likely to be found in ground water?
A
Minerals
3
Q
What is the most commonly used to control algae growth in Reservoir’s?
A
Copper sulfate
4
Q
What are common filtration rates in gravity filtration?
A
2 - 10 gpm/square foot
5
Q
Leakage within a centrifugal pump is intended for what purpose?
A
 Cool moving parts
6
Q
Which of the following is the definition of a grab sample?
A
A single sample of water collected at a particular time and place which represents the composition of the water only at that time and place
7
Q
Adding sodium hypochlorite to water will have the following effect
A
 Increase pH
8
Q
What is the purpose of the ground water rule?
A
To protect the groundwater from disease, causing microorganisms
9
Q
What is true about the total coliform rule?
A
 Establishes an MCL based on the presence and absence of total coliforms or E. coli
10
Q
What will happen to the water quality if Chlorine is injected at the same location as power activated carbon (PAC)
A
Chlorine will react with carbon and neutralize the effects of both
11
Q
Which of the following will react with chlorine to form  trihalomethane?
A
 Natural organic matter
12
Q
What type of pump has a piston within the casing?
A
Reciprocating
13
Q
What must be located near a hazardous chemical storage room?
A
SDS
14
Q
What term describes the depression of a water table?
A
 Cone of depression
15
Q
What is the radius of influence?
A
 The radial distance from the center of a well bore to the point where there is no lowering the water table
16
Q
What is the best way to monitor filter performance?
A
 Turbidity
17
Q
What causes the water to look cloudy?
A
Suspended material
18
Q
Which chemical is sprayed near a chlorine gas leak to produce white smoke?
A
Ammonia
19
Q
Which water sampling parameters must be taken in the field?
A
PH and temperature
20
Q
If the total coliform tests positive, then what must be done next?
A
Test for fecal coliform
21
Q
What is performed to evaluate susceptibility to potential threats and identify corrective actions that can reduce, or mitigate the risk for a water system?
A
Vulnerability assessment
22
Q
What is the definition of holding time for water samples?
A
The length of time a water sample is retained between taking the sample and laboratory analysis
23
Q
From a bacteriological standpoint, what is important for a well?
A
Protect it from contaminating runoff
24
Q
What is true of chlorine gas?
A
It is 2.5 times heavier than air
25
What happens after breakpoint chlorination is achieved?
Chlorine dose and residual increase at the same rate
26
If chlorine residual is not detected after 3 mg/L of dosage is applied, then what might be occurring in the water?
Demand has not been met
27
Which of the following is an indicator organism for pathogens?
Coliform
28
What would happen if there is an increase in turbidity, organics and manganese in the water
Increase in chlorine demand
29
Which of the following would increase alkalinity in the water?
CaCO3
Calcium carbonate
30
If you drop the lid of a sample bottle prior to sampling, what should you do?
Use a new container
31
What is the purpose of the lantern ring in a centrifugal pump?
Provide lubrication and cooling
32
What is the definition of Well drawdown?
Distance between static and pumping water level
33
What should be done with a water sample that cannot be analyzed in a timely manner
Refrigerate it
34
Which of the following source water with most likely contain cryptosporidium and giardia?
Stream
35
What is the purpose of chlorine residual?
Provides a safeguard to kill additional microorganism, encountered after treatment
36
Which of the following is equivalent to 3 log removal?
99.9%
37
How is turbidity measured?
Nephelommetric
38
Which chemical is used to dechlorinate water?
Sodium thiosulfate
39
What must you wear prior to being exposed to chlorine gas?
Self-contained, breathing apparatus, SCBA
40
What is the minimum chlorine concentration required prior to introducing the effluent from the surface water filtration plant to the distribution system?
0.2 ppm
41
Which of the following best describes a water table?
Upper water surface of an aquifer
42
The total coliform rule applies to which of the following water systems?
All public water systems
43
What is the purpose of a shaft sleeve in a pump?
Protects the shaft from wear at stuffing box
44
Why isn’t chlorine injected immediately prior to filtration?
Increases trihalomethane’s (THM)
45
What is a disinfection byproduct?
Trihalomethane
46
Which of the following is used to describe a well that is under pressure?
Artesian well
47
What would cause high concentration of nitrate in ground water?
Over fertilization of land
48
What is the purpose of the lead and copper rule?
Protect the public health by minimizing lead, and copper in drinking water, primarily by reducing water corrosivity
49
Which of the following is not affected by chlorine dose?
 Hardness
50
How long should you run the water before you grab the water sample?
2 to 3 minutes
51
Which of the following is a typical form of calcium hypochlorite?
65% solid tablet
52
Frosting around the outlet connection of a chlorine gas cylinder indicates which of the following?
Reduced flow of chlorine gas
53
Which of the following describes trickling of water from the ground surface towards the aquifer?
Percolation
54
What is a likely discharge of industrial waste found in surface water?
Organic solvents
55
Why shouldn’t you have zero pressure in a water main?
Back siphonage may contaminated the water main
56
What should be inside a simple bottle when obtaining a sample from a coliform test?
Sodium thiosulfate
57
If the MCL for a constituent is violated, who is responsible for notifying the customers about this?
Water purveyor
58
What is the typical concentration of sodium hypochlorite?
12.5%
59
If 2.5 mg/L of chlorine is dosed and there is 0.5 mg/L of residual. What is the reason for the residual?
The residual is present as a safeguard for unanticipated chlorine demand in the distribution system
60
Which of the following must always be done before repairing a pump?
Lock out equipment
61
Which of the following is least likely to affect the effectiveness of chlorine?
Sodium
62
Which of the following is considered safe to drink?
A. Colifirm found in 10% of samples
B. No pathogens.
C. TTHM at 1 mg/L
D. Lead at 1 mg/L
B. No pathogens.
63
Which reading must be taken in the field when obtaining a sample?
Hardness, color, conductance, or chlorine residual ?
Chlorine residual
64
Which of the following devices will give you the hydrogen ion concentration?
pH meter
65
Which of the following is the correct laboratory procedure? Add water to acid. Titrate water to acid. Mix acid with a pH of 2 with a base of pH 12. Or add acid to water.
Add acid to water
66
When dealing with a high-pressure pipeline, which must you do?
Open and close valve slowly
67
Which of the following water source is more likely to have iron and manganese? Lake, ground water, river, or stream?
Groundwater
68
Which will affect chlorine demand the most? Calcium, magnesium, sand, or turbidity and organics.
Turbidity and organics
69
Which will make chlorine more effective in water? Significant decrease in temperature. Constant temperature. Moderate increase in temperature. Or a slight decrease in temperature.
Moderate increase in temperature
70
What are colloidal particles?
Very small particles that do not dissolve and remain dispersed in a liquid for a long time due to the small size and electrical charge.
71
What is alkalinity?
The capacity of water to neutralize acid
72
What does MCL stand for?
Maximum contaminant level
73
What is the zone of saturation?
Aquifer
74
What is a hydrologic cycle?
Continuous movement of water through out the planet
75
What typically occurs at the beginning of a breakpoint chlorination curve?
Chlorine destroyed by reducing compounds
76
What is the drawback of pre-chlorination?
Formation of THM’s
77
How long should the tap remain turned off before grabbing a sample for a lead and copper test?
6 hours
78
The secondary MCL is set for what purpose?
Aesthetic
79
Which of the following will lead to an illness? Iron, manganese, color, or nitrate?
Nitrate
80
What is the most likely cause of decreasing chlorine residual in the water main?
Bacteria and organics may be present
81
What is the aquifer typically composed of?
Sand and gravel
82
What is used to lower pH in water?
CO2
83
What is the maximum allowable chlorine residual concentration in the distribution main?
4 mg/L
84
Why is Trihalomethane considered to be harmful?
 It is carcinogenic
85
Which of the following describes turbidity? In organic salts, calcium and magnesium, soluble iron and manganese, or cloudiness/haziness of a fluid caused by suspended solids?
Cloudiness/haziness of a fluid caused by suspended solids
86
What is a pathogen?
Disease causing microorganism
87
What is the impact of algae to water quality?
Taste and odor problems
88
What is the concentration of chlorine gas?
100%
89
Which of the following is not used to mix coagulants? Hydraulic mixing, mechanical mixing, diffuser, or horizontal paddle wheel?
Horizontal paddle wheel
90
What is considered to be a quick remedy to address a sudden increase in filtered water turbidity?
Feed a filter aid chemical to filter influent
91
What is the likely cause of a pinging noise in a pump?
Cavitation
92
Which of the following controls the efficiency of removing suspended solids in the sedimentation process?
Minimizing mudball formation, sodium hydroxide, flow rate, or proper backwashing
Flow rate
93
What is a sanitary survey?
An analysis to determine all potential water quality impacts to a proposed well
94
Which of the following categories does bacteria belong to? Dissolved, settleable, inorganic, or colloidal.
Colloidal
95
Under the surface water treatment rule what must the reduction of viruses be through filtration and disinfection?
99.99%
96
Which of the following is not considered free residual chlorine?
Hypochlorous acid, Hypochlorite ion, monochloramine or chlorine
Monochloramine
97
Why is coliform used as an indicator organism?
It reduces the complexity and cost of analysis
98
What is an example of a non-community non-transient water system? School, rest, stop, subdivision or retirement community.
School
99
What is the purpose of a packing in a pump?
Control the leakage of water along the pump shaft, and prevent air from entering along the shaft when the pump is in a suction lift condition
100
What does the addition of carbon dioxide do to the pH of water?
Lowers it
101
What is in unconfined aquifer?
One in which ground water possesses a free surface open to the atmosphere
102
What is static water level in a well?
Water level when pump is not running
103
Which of the following will least likely impact the formation of flocs during the coagulation and flocculation process? Alkalinity, pH, temperature or hardness
Hardness
104
What is formed when free chlorine reacts with ammonia?
Chloramine
105
Which contaminant causes blue baby syndrome?
Nitrate
106
What is free chlorine?
The concentration of residual chlorine in water, which is present as dissolved gas (CL2), hypochlorous acid (HOCL), and/or hypochlorite ion (OCL)
107
What is thermocline?
A thin but distinct layer in a Reservoir in which temperature changes more rapidly with depth than it does in the layers above or below
108
What agency protects the health and safety in industrial employees
OSHA
109
What is the first priority in water treatment?
Production of safe, drinking water
110
What is the health effect of consuming water with high levels of lead?
Cardiovascular effects, increased blood pressure and incidence of hypertension
111
What is an imaginary surface to which groundwater rises under hydrostatic pressure in wells or springs?
Piezometric surface
112
What is used to evaluate new coagulants or polymers being considered for use at the plant?
Jar test
113
What are the four zones of a clarifier?
Inlet, outlet, settling, sludge
114
Which type of filtration process is approved by the surface water treatment rule? Nano filtration, conventional water treatment, ion exchange or microfiltration?
Conventional water treatment
115
Which of the following impacts the color of source water?
Organics such as soil and leaves
116
Coliform is most likely to be found in which of the following water supply? Lake, artesian, deep well, shallow well?
Lake
117
What is the amount of water that can be withdrawn from an aquifer without significant environmental impact?
Safe yield
118
pH Will increase if the following chemical is added to water.
Ammonia
119
Which of the following is an unstable form of disinfection?
Ozonation
120
How many stages are in break point chlorination curve?
4
121
Chlorine demand is best described as which of the following?
Chlorine dose minus (-) chlorine residual
122
What is an example of a natural organic matter?
Fallen leaves
123
What is a typical characteristic of a colloidal particle in raw water?
Negative charge on the surface
124
What is short circuiting in a clarifier?
Shorter settling time in basin
125
What would cause a filter to begin backwashing?
Headloss
126
What is the purpose of surface washing in the filtration unit?
Break up mud balls
127
Where would you most likely see high levels of nitrate in the ground water supply?
Near agricultural land
128
What is adsorption?
Constituent sticking to the surface of a substance
129
In which part of the water treatment plant or 99% of the suspended solids removed?
Sedimentation and filtration
130
Which of the following will most likely lead to the lower concentrations of the THM’s entry water? Chloramines, calcium hypochlorite, chlorine gas or sodium hypochlorite
Chloramines
131
Which of the following is not true about the total coliform rule?
A. Uses a presence and absence approach.
B. Compliance is determined on a monthly basis.
C. Each total coliform positive routine sample must be tested for the presence of fecal coliforms.
D. Smaller systems that collect fewer than 40 samples cannot have coliform positive results in more than two samples per month.
Smaller systems that collect fewer than 40 samples cannot have coliform positive results in more than two samples per month
132
Which of the following is true about feasible plugs on a chlorine container?
Never remove it
133
What is the most common water quality complaint from customers?
Taste an odor problems
134
What information should be identified on the sampling container?
Sampling location, date, and time
135
What is the standard requirement for conventional and direct filtration
Filtered water must be less than or equal to 0.3 NTU in 95% of monthly measurements.
136
What is the main drawback of using sodium hypochlorite to disinfect water?
Formation of THM’s
137
What is one of the causes of hardness in water?
Calcium
138
Which chemical is used to raise pH in water?
Soda ash
139
What is the purpose of flocculation?
Slowly stir water to bring smaller flocs together to form, larger ones
140
Which of the following range of pH is considered to be acidic?
0-6
141
What is the term used to describe the upper layer of the stratified reservoir?
Epilimnion
142
What is another name for the multiple tube fermentation test?
MPN
143
What impact does precipitated manganese have on water?
Blackish water
144
Which of the following is not part of the surface water treatment rule?
A. Applies to all public water systems using surface water, sources or ground water sources under the direct influence of surface water.
B. Requires most water systems to filter and disinfect water from surface water sources
C. Establishes Max contaminant level goals for viruses, bacteria, and Giardia
D. All water systems are allowed to use disinfection only for surface water sources that meet criteria for water quality and watershed protection.
All water systems are allowed to use disinfection only for surface water sources that meet criteria for water quality and watershed protection
145
What is a typical characteristic of chlorine gas?
Greenish yellow color
146
Which of the following is not true about the total coliform rule?
A. Each total coliform positive routine sample must be tested for the presence of fecal coliforms or E. coli.
B. If any routine sample is total coliform positive repeat samples are required.
C. Establishes a max contaminant level based on the presence or absence of total coliforms.
D. Monthly sampling requirements are not based on population service.
D. Monthly sampling requirements are not based on population in Served
147
What can be done to minimize the formation of THM?
Eliminate or reduce chlorination before the filters
148
What is the source of fecal coliform bacteria?
Feces
149
What is the drawback of using UV for disinfection?
High energy cost
150
What are the two types of aquifers?
Confined and unconfined
151
What is a common problem associated with hardness in water?
Scaling
152
What is the problem with very soft water?
Corrosion
153
Why is it harmful to backwash at a high velocity?
Flushes some media into spent backwash water
154
What occurs on the right side of the breakpoint chlorination curve?
Free available residual Chlorine will begin to form
155
How does PAC remove contaminants from the water?
Adsorption
156
Which entity is responsible for enforcing the drinking water standards?
State
157
How is the rate of Headloss affected by a more uniform filter media?
Slower
158
Which of the following is true about soluble iron and manganese?
Colorless
159
What is the reason for adding coagulants at the flash mixer?
Neutralize negative charge on colloids
160
Why would a water purveyor switch from chlorine gas to sodium hypochlorite?
Safety
161
Which pathogen is smallest in size?
Bacteria, protozoa, cyst or virus
Virus
162
Which of the following is not an example of a suspended solids?
Silt, decaying plants, animal matter, or soluble calcium
Soluble calcium
163
Which of the following is not a type of a coliform test?
Multiple tube fermentation method, membrane filter method, DPD or colilert method
DPD 
164
What is the definition of a public water system?
Publicly or privately owned water system that has at least 15 service connections, or regularly serves an average of at least 25 people daily at least 60 days per year.
165
When is brilliant green bile used to test coliform?
Multiple tube fermentation method
166
Which of the following is the correct order of treatment for a conventional water treatment plant?
Intake, coagulation, fluctuation, sedimentation, filtration, disinfection
167
What might happen if insufficient amounts of coagulants were injected into the flash mixer?
Some colloids may repel each other
168
Which of the following is a grab sample?
Sample taken on a one time basis without consideration of flow or time
169
What happens over the course of a filter runtime?
Headloss increases
170
When is direct filtration used instead of conventional water treatment?
When source water is low in turbidity, color and coliform
