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214 Cards in this Set

  • Front
  • Back
The objective of disinfecting water is to kill _____________
___________ _______________
disease causing organisms.
There are several methods for disinfecting water. Which of the following are most widely used in drinking water applications?

a. Ozonation and Iodine
b. Chlorine and bromine
c. Ultraviolet and potassium permanganate
d. Overliming and copper sulfite
b. Chlorine and bromine
True or False

Chlorine gas will have an amber color when exposed to air.
False
Chlorine gas is ____________times heavier than air.
2.5
If you are receiving complaints on chlorine smell in the drinking water what would you typically do?

a. Turn the chlorine down to lower the residual
b. Turn the chlorine up to reach break point.
c. Flush hydrants
d. backwash filters
b. Turn the chlorine up to reach break point.
True or False

Gas chlorine cylinders should be located directly in front of heaters to prevent cylinders from freezing up.
False
True or False

Chlorine residuals in a distribution system should be taken at the furthest locations from the well or treatment plant.
True
True or False

Chlorine is safe if handled properly
True
If you have a minimum free chlorine residual throughout your distribution system, you have:

a. Proper chloramine residual
b. Overfed chlorine
c. Breakpoint chlorination
d. Monochloramine compound
c. Breakpoint chlorination
When mixing solutions of acid and water together, liquid chlorine or fluoride, you should always mix the:

a. water to the acid
b. acid to the water
c. never mix together
d. any order
b. acid to the water
True or False

The PH of most natural waters is 6.5 - 7.5, chlorine is most effective at a higher PH.
False

(The lower the PH, the better the disinfection)
This species of chlorine is the most germicidal of all chlorine compounds with the possible exception of chlorine dioxide.

a. Hypochlorite Ion
b. Elemental chlorine
c. Hypochlorous acid
d. Hypochloric acid
c. Hypochlorous acid
Which is a common test used to estimate the total bacterial population in water?

a. total coliform analyses
b. presence-absence test
c. a measurement of zeta potential
d. heterotrophic plate count
d. heterotrophic plate count
Suspended particles are caused by _______ in water
turbidity
Records of action taken to correct violations must be kept for atleast _____ years.
Three
True or False

Chlorination equipment shall be capable of keeping a free chlorine residual of 2 ppm for at least 30 minutes in finished water at peak flow.
True
True or False

Turbidity in drinking water may not exceed 0.5 NTU in 95% of samples each month.
True
A person drinking water containing a particular contaminant above this level over their lifetime could experience ill effects. This would be an enforceable standard.
a. Treatment Technique Requirements (TTR)
b. Maximum Contaminant Level Goal (MCLG)
c. Maximum Contaminent Level (MCL)
d. None of the above
c. Maximum Contaminent Level (MCL)
The Total Coliform Rule (TCR) for all water supplies sets the MCL at:

a. 10
b. 2 per sample
c. Less than 100
d. None present
d. None present
The number of samples collected for total colifom per month is based on:
b. population served
Samples for total bacteria should be collected at what points in the system?
Random representative samples
Total coliform samples should be analyzed by the lab within how many hours?
30 hours
When coliform organisms are found in a routine sample, the water supplier must test for:

a. turbidity
b. fecal and E coli
c. hardness
d. nitrates
b. fecal and E coli
Results of bacteriological analysis must be kept for how many years?
5
Which chemical is added to a distribution system to deal with dental issues?
fluoride
What is the primary health risk associated with VOCs in the distribution system?
cancer
True or False

Hydrogen sulfide gas can be dangerous if inhaled in even low concentrations.
True
The Total Coliform Rule is based on the:

a. size of the coliform colony
b. presence or absense of coliform
c. number of coliform colonies
d. All of the above
b. presence or absense of coliform
How full do you fill a sample bottle when collecting a sample for bacteriological testing?

a. full to the top with no air bubbles
b. half full
c. within 1 inch of the top
d. almost full
c. within 1 inch of the top
Primary MCLs are related to which of the following water quality conditions?
a. appearance
b. color and odor
c. health effects
d. all of the above
c. health effects
True or False

Polymers must be approved for potable water use by the regulating agency.
True
True Or False

Polymers do not consume alkalinity.
True
Combination treatment units incorporate:

a. coagulation
b. flocculation
c. sedimentation
d all of the above
d all of the above
Sedimentation basins:

a. Are used in conventional treatment plants
b. settle out the flocs
c. proceed filtration
d. all of the above
d. all of the above
Flocculation is a:

a. slow mix process
b. rapid mix process
c. takes 1 - 4 minutes
d. none of the above
a. slow mix process
True or False

Coagulants are added to neutralize the charge carried by suspended solids.
True
Most suspended particles possess a:

a. negative charge
b. positive charge
c. none of the above
a. negative charge
Coagulation and flocculation processes are used to:

a. decrease water temperature
b. soften water
c. separate suspended solids from the water
d. remove chlorine residual
c. separate suspended solids from the water
Sedimentation tanks are divided into 3 zones"
c. Inlet zone, settling zone, sludge zone.
What can be done to eliminate short circuiting of a tank?
a. increase water velocity.
b. Install baffles.
c. all of the above
d. none of the above
b. Install baffles.
When water temperature decreases

a. settling increases
b. settling decreases
c. detention time may be increased
d. none of the above
b. settling decreases
True or False

All particles have a slight electrical charge.
True
Potassium permanganate would be the most effective oxidizing agent when you have high levels of:

a. iron
b. magnesium
c. manganese
d. calcium
c. manganese
The most common and affordable method for oxidizing iron and manganese before filtration is:

a. potassium permanganate
b. chlorine
c. PH adjustment
d. aeration
d. aeration
Polyphosphates are only effective in masking or (sequestering) iron and manganese in what chemical state?

a. ferrous and manganous
b. ferric and mananic
a. ferrous and manganous
What is the secondary standard for manganese under (SDWA)?
0.05 ppm
What is the secondary standard set by the SDWA for iron in parts per million?
0.3ppm
Iron bacteria which can be a product of high iron levels in a distribution system can be controlled by:

a. hydrofluoric acid
b. polymers
c. chlorination
d. flushing
c. chlorination
True or False

Iron and manganese can have adverse health
False
Which test is not included in testing for water quality by an ion exchange softener?

a. Total hardness of the raw and treated water.
b. Alkalinity
c. Langelier index
d. chloride concentration in rinsewater.
b. Alkalinity
The compound used in ion exchange water softener is called___.

a. sodium chloride
b. ferric chloride
c. calcium hypochlorite
d. magnesium bicarbonate
a. sodium chloride
Softener media most commonly used are called___.
synthetic zeolite
In ion exchange, calcium and magnesium ions are replaced by __ ions.
sodium ions
A water softener method used extensively in smaller water systems:
ion exchange
Which chemical is used to lower alkalinity?
a. Hydrate lime
b. carbon dioxide
c. calcium hypochlorite
d. sodium aluminate
b. carbon dioxide
Proper lime doses are determined by using the__ test.
jar test
Minimum retention time in a flocculator is:

a. 60 minutes
b. 10 minutes
c. 30 minutes
d. 90 minutes
c. 30 minutes
If volatile organic chemicals (VOCs) are detected, sampling must be conducted:
a. biannually
b. quarterly
c. monthly
d. annually
b. quarterly
According to the lead and copper rule, the action level is:
0.015 mg/L
Reaching or exceeding an action level:
a. triggers a boil-water notice.
b. triggers the initiation of a treatment technique.
c. means a utility must test further to determine exactly what and how much is in the water.
d. can only be determined by the treatment plant.
b. triggers the initiation of a treatment technique.
How many negative coliform samles are required to pass a new water main?
a. one
b. two
c. three
d. four
b. two
Two pumps of the same flow capacity and pressure rating that are piped in series would result in:
a. double the flow, same head.
b. double the discharge head
c. double the flow and head
d. heating of the pumps
b. double the discharge head
Booster pumps are normally used for which situation?
a. pump water from plant to distribution system.
b. increase water pressure in the distribution system.
c. pump water from the source to the plant.
b. increase water pressure in the distribution system.
When do pumps and motors in a water system need maintenance?
a. on a regular basis
b. never needs to be done
c. only when it breaks down
a. on a regular basis
Positive displacement pumps are commonly used to produce what?

a. higher pressure
b. lower pressure
c. not used in water
a. higher pressure
In selecting a pump which one piece of information is needed?

a. draw down
b. static discharge head
c. total dynamic head
c. total dynamic head
Which of the following may be found on a pump curve?
a. size of impeller
b. where pump was made
c. which type of fluid can be pumped
a. size of impeller
1 foot of water = ___ psi
0.433 psi
What type of valve is usually installed on a storage reservoir to prevent overflows?
a. regulating valve
b. altitude valve
c. limiting valve
d. globe valve
b. altitude valve
Which one would be a good example of a vertical turbine pump?
a. centrifugal pump
b. positive displacement pump
c. chemical feed pump
a. centrifugal pump
Hardness of water is mainly caused by the presence of__.
calcium and magnesium
One method of softening public water supplies is:
a. chemical precipitation
b. iron removal filters
c. iron and manganese
d. pretreatment
a. chemical precipitation
Lime and soda ash are two chemicals used in__.
a. disinfection
b. sequestaion
c. chemical precipitation
d. filtration
c. chemical precipitation
The type of fire extinguisher needed for wood, paper, textiles and similar fires:
a. Class A
b. Class B
c. Class C
d. Any of the above
a. Class A
True or False
One horsepower (HP) is defined as 33,000 ft-lbs per minute or 746 watts.
True
Static head is defined as the:
a. pressure created by the atmosphere.
b. the energy of motion of the water.
c. pressure due to depth or elevation of water.
d. pressure loss in a waterline due to friction.
c. pressure due to depth or elevation of water.
What is the term used for electrical pressure that causes current to flow through wires?

a. amperage
b. wattage
c. voltage
d. ohms
c. voltage
What is the term used to describe how hard the electricity is working?
amperage
Direct current that is used in a water system:

a. flows in one direction only
b. flows in any direction
c. is equal to the amount of electricity used
d. never has a positive or negative point
a. flows in one direction only
Alternating current that is used in a water system:
a. flows in one direction only
b. flows in any direction
c. is equal to the amount of electricity used
d. never has a positive or negative point
b. flows in any direction
The purpose of the "Lock Out Tag Out" system is to:
a. prevent equipment from being operated
b. keep people out of the electrical room
c. lock a specific device so that it is not stolen
d. prevent theft
a. prevent equipment from being operated
The most accurate way to deliver accurate volumes of a sample is to use:
a pipette
What mineral is found in water that causes blackish staining of fixtures?
Manganese
When a person or article talks about VOC chemicals in water, what do the letters "VOC" stand for?
Volatile Organic Chemicals
True or False

There is more dissolved oxygen in cold water than in warm.
True
Excessive amounts of fluoride in drinking water can cause:
mottling of teeth
The velocity of flow in water mains is directly related to the__.
a. flow rate in GPM and cross sectional area of the pipe.
b. C-factor and type of pipe.
c. dynamic pressure head and water velocity.
d. specific gravity and density of water.
a. flow rate in GPM and cross sectional area of the pipe.
What would the wire to water efficiency be on a pump that had water horsepower of 22 and motor horsepower of 28?
a. 89%
b. 79%
c. 99%
d. 69%
b. 79%

22x100=2200
2200 divided by 28= 78.5 (79% rounded)
A dynamic suction lift plus dynamic discharge head of a pump is equal to the
a. total level
b. total dynamic head
c. dynamic suction head
d. total static head
b. total dynamic head
How is velocity of water normally expressed?
a. feet per minute
b. gallons per minute
c. liters per inch
d. feet per second
d. feet per second
What are the "Action Levels" for lead within a distribution system?
0.015 mg/L for lead
If water has a PH of below 6.2 it could indicate what?
a. corrosive water
b. high levels of dissolved solids
c. high alkalinity
d. high temperature
a. corrosive water
The difference between the amount of chlorine added to water and the amount of residual chlorine remaining at the end of a specified period is
chlorine demand
What is the number of total coliform samples collected each month in a distribution system based on?
a. type of water source used
b. type of water treatment used
c. amount of water purchased
d. population served
d. population served
Water treatment plants can also minimize taste and odor problems by maintaining an adequate
a. chlorine residual
b. recirculation rates
c. positive pressure
d. pump maintenance program
a. chlorine residual
What involves the prevention of contaminants from entering the groundwater source?
well head protection
Water that has a rotten egg smell usually has a high amount of
a. sulfer
b. hydrogen sulfide
c. Iron magus
d. magnesium
b. hydrogen sulfide
Most taste and odors in surface water are derived from algae blooms and are
a.organic
b. inorganic
a.organic
Typically water system customers judge the quality of water by
a. color
b. taste
c. asthetics
d. all of the above
d. all of the above
Any routine or repeat samples that are found to be positive for total coliform bacteria must be analyzed for
a.iron
b. chlorine residual
c. E-coli or fecal coliform
d. sodium thiosulfate
c. E-coli or fecal coliform
Sodium thiosulfate is used in water sample bottles to
a. sterilize the sample container
b. oxidize iron
c. oxidize manganese
d. neutralize the chlorine in the water sample
d. neutralize the chlorine in the water sample
The ___ group of bacteria is an indicator that one or more pathogens may be present in the drinking water.
a. total colilert
b. total cholera
c. total coliform
c. total coliform
Disease producing organisms in water are also known as ________.
Waterborne pathogens
Any water with a chlorine residual of __ mg/L or more must be diluted with water or properly neutralized before being discharged into the environment
a. 10mg/L
b. 2mg/L
c 7mg/L
b. 2mg/L
Carbonate and non-carbonate are two classifications of
a. well water in a system
b. filtration done at the plant
c. water hardness
d. duel water mains supplying a soft drink plant
c. water hardness
Hardness in water is caused by significant amounts of _______ .
calcium OR magnesium components
Which of the following is a true statement regarding PH and drinking water?
a. PH is measured on a scale of 1 to 10.
b. The normal PH drinking water range is 7 to 9.5
c. Water that is above 7.0 is acidic.
d. PH is the measurement of water's hydrogen ion concentration.
d. PH is the measurement of water's hydrogen ion concentration.
A chlorine room shall have an exhaust ventilation fan that provides how many air exchanges per minute?

a. 1
b. 5
c. 10
d. 12
a. 1
When hydrofluosilicic acid is used, the point of application in a horizontal pipe shall be in which part of the pipe?

a. upper
b. lower
c. somewhere down stream
d. middle
b. lower
Hydrogen sulfide in water is a common problem and a common method of removing it from water is:
aeration
One of the most common methods for measuring the odor in water is:

a. boiling it
b. atomic absorption
c. threshold odor test
d. chlorine test
c. threshold odor test
What gas or chemical can be removed by aeration, realizing that explosiveness is the largest danger?
a. iron
b. magnesium
c. chlorine
d. methane
d. methane
Switches for the lights and fan of a chemical feed room should be located
a. at the control center
b. outside the room door and also at the inspection window.
c. just outside the main entrance
d. in the foreman's office.
b. outside the room door and also at the inspection window.
What is the maximum contaminant level for total trihalomethanes?
b. 0.08 mg/L
A typical method of testing fluoride concentration is the __ method.
SPADNS
Fluoride should enter the __ of the discharge pipe.
a. upper half
b. upper side
c. at the top
d. lower half
d. lower half
In order to prevent the over feeding of fluoride, this device is required

a. weigh scale
b. break box
c. check valve
d. foot valve
b. break box
Methane gas can be removed in water by what method?
aeration
The efficiency of the water aeration process depends on what?
a. the amount of pressure in the air before it's added.
b. the amount of surface contact between the air and water.
c. the PH of the water before aeration.
b. the amount of surface contact between the air and water.
The recommended location for the exhaust fan suction point in a chlorine room is close to the...
a. exit door
b. ceiling
c. floor
d. tank
c. floor
Which of the following elements will create chloramines when chloride is added to water?
a. Ferrous iron
b. ammonia
c. hydrogen sulfide
d. manganese
b. ammonia
If complaints are coming on chlorine smell in the drinking water you would typically
a. turn the chorine down to a lower residual.
b. turn the chlorine up to reach break point chlorination.
c. flush hydrants
d. back wash filters
b. turn the chlorine up to reach break point chlorination.
The desired amount of chlorine residual in a distribution system is
0.2 - 0.5 ppm free residual
True or False
The PH of most natural waters is 6.5 - 7.5. Chlorine is most effective at a higher PH.
False

(The lower the PH, the better the disinfection)
The critical PH level considered in lead corrosion is
a. 7
b. 8
c. 9
d. 10
b. 8
The langelier index is a way to measure
a. the coating ability of water
b. the aggressiveness of water
c. All of the above
d. none of the above
c. All of the above
True or False
Phosphate addition prevents corrosion by laying down a film on the inside of a pipe and preventing contact of an aggressive water with the pipe.
True
Waters with a high alkalinity and a PH of 8 can
a. cause corrosion
b. plug pipes over time
c. have no affect on pipe
d. none of the above
b. plug pipes over time
What happens when lime is fed to water for corrosion control?
a. alkalinity is decreased
b. PH is increased
c. Co2 does not change
d. turbidity is decreased
b. PH is increased
Hardness in water is caused by
a. chloride and fluoride
b. sodium an potassium
c. alum
d. calcium and magnesium
d. calcium and magnesium
What is the action level for copper?
1.3 mg/L
MCL's for Fluoride is ___ mg/l
4 mg/l
MCL's for Nitrate
10 mg/l
MCL's for Nitrite
1 mg/l
Nitrates and Nitrates are believed to cause ______ in infants?
Blue Baby
MCL's for Manganese is
0.05 mg/l
PSI for fire flow
20 psi
PSI for System Peak
30 psi
Chlorine Residual required when disinfecting or bring a new well on line
100 mg/l maintained for 24 hours
A routine coliform test results must be reported to the state by the ____ day of the following month.
10th
The media used in the confirmed test for total coliform bacteria is
BGB - Brilliant Green Bile
Sodium thiosulfate is used to
neutralize chlorine solutions
Pressure in a pipeline may be affected by
friction and elevation
Granular, white, dry powder used for disinfection is
calcium hypochlorite
The miniumum size of distribution pipe is
2 inches
The maximum number of residents allowed on a 2'' line is
20
I fthe line is looped, the maxumum number of residents allowed on a 2'' line is
40
Line must be buried -____ deep or below the frost line, which ever is deeper.
30 inches
The principal purpose of an altitude valve on an elevated tank is to
Control max filling level
What backflow preventer protects against back siphonage?
Reduced Pressure Zone (RPZ)
A cross-connectoin is defined as a connection between
A potable water system and a nonpotable water system.
Back siphonage is caused by
a. excessive pressure in teh line.
b. partial vacuum in the line.
c. a small leak.
d. water hammer.
b. partial vacuume in the line.
Teh primary authority for implementation and enforcement of drinking water regulations is the definition of
Primacy
Lead in drinking water can result in
impaired mental functioning in children.
The term "Maximum contaminant level goal (MCLG)" means the level of a comtaminant in drinking water where there are no
known or suspected adverse healt effects.
The Public Water Supply Section is part of the
Devision of Environmental Health
In NC, the drinking water quality standards are enforced by
The NC Division 0of Environmental Health.
A single sample taken without considering the tme of day or the rate of flow is called a
grab sample.
A primary source of volatile organic chemical (VOC) contamination of water supplies is
a. agriculatural pesticides.
b. industrial solvents.
c. acid rain.
d. agricultural fertilizers.
b. industrial solvents.
The term MCL means
Maximum Contaminate Level
The primary health risk associated with synthetic organic compounds (SOCs) is
Cancer
Lead in drinking water is primarily teh result of
corrosion within the distribution system and plumbing
What is the difference between a maximum contaminant level (MCL) and a secondary maximum contaminant level (SMCL)?
MCLs relate to healt effects
SMCls relate to aesthetic concerns
The maximum contaminant level goal (MCLG) of known or probable carcinognes is
a. sent by the state
b. teh same as the MCL
c. zero
C. zero
The water table can be defined as the
a. upper surface of the ground water.
b. pumping level in a well.
c. water level in a reservior.
a. upper surface of the ground water
When the pumping rate is increased, the effect on the cone of depression is to
a. decrease the drawdown.
b. decrease the radius of influence.
c. lower the pumping level.
c. Lower the pumping level.
The difference between the static level and the pumping level of a well is called teh
drawdown
The water table is defined as the
a. upper surface level of the zone of saturation
b. water level in a reservior.
d. pumping level in a well.
a. upper surface level of the zone of saturation.
The average percentage range for unaccounted-for water in a fully metered system is
11-15%
Hardness may be expressed in mg/l as
CaCO3
A Public Wate Systme is one that serves _________ or more service connections or regularly serves ________ or more individuals.
a. 5.10
b. 10,15
c. 15,25
c. 15, 25
Check valves are used to prevent water from flowing in _________ directions
two
The main purpose of pump priming is to replace ____ with ________ inside the pump.
air, water
Which component of a contrifugal pump moves the water?
Impeller
The shaft speed of an electric motor is most commonly expressed in units of
revolutions per minute
The component of a centrifugal pump sometimes installed on the end of a suction pipe to hold the priming is known as a
foot valve.
Riciprocating positive-displacement pumps are also known as
piston pumps.
The pressure that a pump must operate against is measured in
a. foot pounds.
b. milligrams per liter.
c. pounds per sq. in.
c. pounds per sq. in.
The term for the pressure against which a pump must operate is
Head
During confined space entry the confined space must be monitored _____________for hazardous atmospheres?
continuously
An electrical fire is a class __________ fire.
C
The radius required by PWSS for an approvable well site is _______ feet.
100
The Well Construction Standards are enforced by
Water Quality
The minimum depth for grout according to the well construction standards is _________ feet.
a. 10
b. 15
C. 20
20
The component parts of a well include all of the following except...
a. sanitary seal
b. well screen
c. pressure switch
d. cement grout
C. Pressure switch
A disease that might be transferred to a new victim through water is
a. diphteria
b. malaria
c. typhoid
C. typhoid
Violations for microbiological MCLs must be reported to the State no later than
a. next business day after you learn of the violation
b. 24 hours
c. 48 hours
A. next business day after you learn of the violation
How many gallons are 1 cubic foot
7.48 gal/cubed ft
1 gallon of water is how many pounds
8.34lbs/gal
1.0 psi is ______ feet of water
2.31 feet
1.0 million gallons per day (MGD) is __________ gallons per minute (GPM).
694

1,000,000 / 1440 = 694
How many minutes are in 1 day
1440
Velocity
Feet per Seconds
Flow =
Flow = Area x Velocity
Water Volume
Rectangle V = L (length of pipe ) x W x H x 7.48

Circle V= R x R x 3.14 x L (length of pipe) x 7.48
Area
Rectangle A= L x W

Circle A = R x R x 3.14
1 mile is ___________ feet.
5,280
1 gallon of HFS weights _________ lbs.
10lbs/gal
1 gallong of PO4 weighs ___________ lbs.
11.7lbs/gal
1 inch of murcury is __________ feet of water.
1.13
Pounds Formula
lbs = mg/L x 8.34 x MGD

mg/L = lbs / (8.34 x MGD)

MGD = lbs / (8.34 x mg/L)
What is the typical strenght of calcium hypochlorite?
a. 5-10%
b. 45-50%
c. 65-70%
c. 65-70%
Ph is a measure of
a. conductivity
b. waters ability to neutralize acid
c. hydrogen ion concentration
d. dissolved solids
C. hydrogen ion concentration
What does DPD stand for?
Disinfection by-product
Which of the following has both a primary and a secondary standard?
Fluoride
Which of the following violations is considered the most serious?
a. Tier 1
b. Tier 2
c. Tier 1-A
Tier 1
The Riparian Doctrine is sometimes called the Rule of __________.
Reasonable Sharing
A water course that flows continuously at all times of the year is called _____________stream.
Perennial
As water temp. increases, the disinfection action of chlorine will
a. increase
b. decrease
c. double
a. increase
Which of the following fluoride compounds comes in soultion form?
a. fluorosilicic acid
b. sodium fluoride
c. fluorind gas
A. fluorosilicic acid
What is the correct formula for determining watts?
a. = volts/amps
b. = horsepower x ohms
c. = amps x volts
c. amps x volts
Specific Capacity Formula
SC = well yield in gallons / drawdown

measured in gals/min per foot of drawdown
Detention Time Formula
DT = volume (gal) / Flow

Answer is in minutes and you must convert to hours by deviding answer by 60 (minutes in an hour).
What is the Langalier Index?
an approximate indicator of the degree of saturation of calcium carbonate in water.