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114 Cards in this Set

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1) When organic wastes are discharged to receiving waters, oxygen is depleted by
a) Algae during the day
b) Bacteria
c) Ducks
d) Limestone rocks
b) Bacteria
Bacteria is the correct answer.

Algae produce oxygen during the day, and respire & use oxygen in the dark.

Ducks breath oxygen that is in the air not the water

Limestone buffers the pH of water but does nothing to the oxygen content.
2) Employee hazards include
a) Noxious or toxic gases or vapors
b) Oxygen deficiency
c) Physical injuries
d) All of the above
d) All of the above
Noxious & toxic gases or vapors can come from a variety of sources, industries, hydrogen sulfide from decomposing organic materials in the collection system.

Oxygen deficiency may be caused by bacteria using up all the oxygen while decomposing organic matter. Or oxygen being displaced by a heavier or lighter gas.

Physical injuries from moving equipment parts or sharp material in the wastewater.
3) Hydrogen sulfide gives off an odor similar to
a) Ammonia
b) Chlorine gas
c) Rotten eggs
d) Decayed wood
c) Rotten eggs
4) Coliforms Bacteria are
a) Algae
b) Coagulant aids
c) Indicators
d) Sequestering agents
c) Indicators
a) In general Algae are plants with chlorophyll and bacteria are animals.

b) Coagulant aids are like polymers and ferric chloride that bring particles together to make larger particles. Coagulants are often used in wastewater to help remove water from sludge or enhance the settling and removal of pollutants in wastewater.

c) Coliform bacteria are used to indicate how well the disinfection process has worked. Although Coliform bacteria are not themselves considered disease causing, they are used as an indicator as to how well the process has killed off other disease causing bacteria.
5) Three Waterborne diseases are
a) Mumps, Measles, colds
b) Scarlet fever, pneumonia, hay fever
c) Typhoid fever, dysentery, cholera
d) TB, diphtheria, chickenpox
c) Typhoid fever, dysentery, cholera
6) A cylindrical tank is 10 feet in diameter and 20 feet in height.
What is the approximate capacity in liters?
Formula
a) 44,450
b) 31,030
c) 5,942
d) 4,445
a) 44,450
pR2h = volume of cylinder
5ft * 5ft * 3.14 * 20ft = 1570 ft3
Formula-1 ft3 = 7.48 gallons
1570 ft3 * 7.48 gallons/ft3 = 11744 gallons
1 gallon = 3.785 liters
23487 gallons * 3.785 liters /gallon =44,450 liters
Formula pR2h = volume of cylinder

5ft * 5ft * 3.14 * 20ft = 1570 ft3



Formula 1 ft3 = 7.48 gallons

1570 ft3 * 7.48 gallons/ft3 = 11744 gallons



formula 1 gallon = 3.785 liters
23487 gallons * 3.785 liters /gallon =44,450 liters
7) First Aid for first degree burns
a) Bandage tightly
b) Cover liberally with a salve
c) Immerse in warm water
d) Immerse in cold water
d) Immerse in cold water

A first degree burn is the lowest level burn and a third degree burn is the worst.
8) Which of these pH readings indicates an acidic wastewater?
a) 3
b) 7
c) 9
d) 20
a) 3
The pH scale goes from 0 to 14. A pH of 7 is neutral neither acidic nor alkaline (base). Any pH reading below 7 is acidic and above 7 is alkaline.
The pH scale goes from 0 to 14. A pH of 7 is neutral neither acidic nor alkaline (base). Any pH reading below 7 is acidic and above 7 is alkaline.
9) If water weighs 8.34 pounds per gallon, how much will seven and one-half gallons weigh?
Formula
a) 50 pounds
b) 62.5 pounds
c) 75.6 pounds
d) 77 pounds
b) 62.5 pounds
1 gallon water = 8.34 lbs 8.34lbs/gal * 7.5 gal = 62.5 lbs
1 gallon water = 8.34 lbs of water



8.34 lbs/gal * 7.5 gal = 62.5 lbs
10)One milliliter is what fraction of a liter?
a) 1/10
b) 1/100
c) 1/1000
d) 1/1000,000
c) 1/1000
mega = 1,000,000 = M
kilo = 1,000 = k
hecto = 100 = h
deca = 10 = da
deci = 1/10 =d
centi = 1/100 =c
milli = 1/1,000 =m
micro = 1/1,000,000 =m
nano = 1,000,000,000 =n
11)The normal cause of electric motor failure is
a) Dirt
b) Moisture
c) Friction
d) All of the above
d) All of the above
12)A pump can deliver 400 gallons per minute at a total head of 184.8 feet. What is the pressure equivalent to this head, expressed in lbs per square inch?
Formula
a) 42.7 psi
b) 80 psi
c) 427 psi
d) None of the above
b) 80 psi
1 foot of water column = 2.31 psi
Formula 1 foot of water column = 2.31 psi
13)Approximately how many gallons of wastewater would a 600 feet of 6 inch pipe hold?
Formula
a) 740
b) 880
c) 900
d) 930
b) 880
1ft =12 inches
6 inches * 1ft/12 inches = pipe diameter of 0.5 ft
Volume of a cylinder = pR2h
3.14 * (.25 ft * .25ft) * 600 ft = 118 ft3
1 ft3 = 7.48 gallons
118 ft3 * 7.48 gal/ft3 = 880 gal
formula 1ft =12 inches



6 inches * 1ft/12 inches = pipe diameter of 0.5 ft



Formula Volume of a cylinder = pR2h



3.14 * (.25 ft * .25ft) * 600 ft = 118 ft3



Formula 1 ft3 = 7.48 gallons



118 ft3 * 7.48 gal/ft3 = 880 gal
14)A water seal on a pump serves a dual purpose. It acts as a lubricant and it also
a) Acts as a coolant to keep the pump bearings from overheating
b) Keeps gritty material from entering the packing box
c) Keeps the pump primed
d) Is a reserve water supply?
b) Keeps gritty material from entering the packing box
15)The elevation of any pump above the source of the supply should not exceed ______feet.
a) 2.2
b) 22
c) 200
d) 224
b) 22
16)The three common types of plastic pipe are listed as: PVC, PE and ABS.
These Names refer to the
a) Chemical resistance of the pipe
b) Composition of the pipe
c) Pressure for which the pipe is designed
d) Types of appropriate application
a) Chemical resistance of the pipe
b) Composition of the pipe
c) Pressure for which the pipe is designed
d) Types of appropriate application

find anser
17)Prior to repairing a pump’s electrical circuit, which of the following actions should you take?
a) Disconnect the circuit breaker, and place a red tag stating, “do not activate”, and lock out.
b) Notify your supervisor.
c) Tell all of the operators not to activate the circuit.
d) Turn the pump off.
a) Disconnect the circuit breaker, and place a red tag stating “do not activate”, and lock out.
18)Pump maintenance includes
a) Checking operating temperature of bearings
b) Checking packing gland
c) Operating two or more pumps of the same size alternately to equalize wear
d) All of the above
d) All of the above
19)When carrying out a routine inspection on a centrifugal pump. It is noted by the operator that the bearings are excessively hot.
This could be caused by
a) Over lubrication
b) Speed too slow
c) Worn impeller
d) Worn packing
e) Both c & d
a) Over lubrication
20)In a centrifugal pump, internal leakage is prevented by
a) Impellers
b) Sleeves
c) Volutes
d) Wear rings
d) Wear rings
Impeller turns the liquid at a high rate of speed ( the heart of the pump)
Sleeves protect the shaft from the liquid
Volutes are the housing on pumps that contain the impellers and liquid inside
Wear rings prevent internal leakage
Impeller turns the liquid at a high rate of speed ( the heart of the pump)

Sleeves protect the shaft from the liquid

Volutes are the housing on pumps that contain the impellers and liquid inside

Wear rings prevent internal leakage
21)A valve that allows water to flow in one direction only is a _______ valve
a) Check
b) Gate
c) Globe
d) Petcock
a) Check
Check valve allows one way flow of liquids Gate valves are flat plates that are used usually to cut flow off completely Globe valves are used to cut off or throttle flow and are round A petcock is round or conical valve with a hole in the center of it. Often used in laboratory equipment on burettes
Check valve allows one way flow of liquids

Gate valves are flat plates that are used usually to cut flow off completely

Globe valves are used to cut off or throttle flow and are round

A petcock is round or conical valve with a hole in the center of it. Often used in laboratory equipment on burettes
22)Pipe material that is the least susceptible to corrosion by acids formed from hydrogen sulfide gas is
a) ACP
b) CIP
c) RCP
d) VCP
d) VCP
23)Centrifugal pump parts include
a) Diaphragm
b) Impeller
c) Piston
d) Rotor
e) Both b & d
b) Impeller
24)Which indicates good quality domestic activated sludge
a) Black color and septic odor
b) Brown color and musty odor
c) Brown color with lots of dark brown foam
d) Settle ability of 900 malls in a liter cylinder over a 30 minute period
b) Brown color and musty odor
Settleabiltiy in and of itself does not tell you enough information, and 900 mls in 30 minute with a normal concentration of MLSS is usually high and an indication of some kind of bulking.
The black color and septic odor usually indicates not enough aeration

A brown color and musty odor, usually means a healthly activated sludge (I like to think of it as liquid soil)



Settleabiltiy in and of itself does not tell you enough information, and 900 mls in 30 minute with a normal concentration of MLSS is usually high and an indication of some kind of bulking.
25)Which of the following forms of plant life is necessary for the proper functioning of a stabilization or oxidation pond?
a) Algae
b) Cattails
c) Water lilies
d) Weeds
e) Both a & c
a) Algae
26)Cattails growing in a lagoon will
a) Cause short circuiting in affected lagoon
b) Eliminate mosquito larvae
c) Stabilize the sediment in the pond
d) Increase diurnal pH fluctuations
e) Increase toxic blue-green algae concentrations in the effluent
a) Cause short circuiting in affected lagoon
27)At what time of day is the dissolved oxygen content highest in a waste stabilization lagoon?
a) 3 am
b) 7 am
c) 9 am
d) 12 (noon)
e) 3 pm
e) 3 pm
28)The greatest bacterial activity and the highest BOD5 removal in a waste stabilization lagoon will occur when there is
a) Good sunlight, cold temperatures and strong wind
b) Warm temperature, strong wind and heavily overcast
c) Moderate breeze, cold temperature and good sunlight
d) Warm temperature, moderate breeze and good sunlight
d) Warm temperature, moderate breeze and good sunlight
29)Chlorine gas is
a) Colorless
b) Heavier than air
c) Non-toxic
d) Odorless
e) Both a & c
b) Heavier than air
30)Acids should never be added to chlorine solutions as they
a) Cause chlorine gas to be released
b) Corrode or “eat away” the solution tank
c) Decrease the disinfecting properties of chlorine
d) Result in the formation of a chloride precipitate
e) All of the above
a) Cause chlorine gas to be released
31)As water temperatures decrease, the disinfecting action of chlorine
a) Decreases
b) Increases
c) Remains the same
a) Decreases
32)The highest concentration of algae growth in a lagoon is usually observed
a) Near mid-depth
b) Near bottom
c) Near top
d) Below 10.0 feet
c) Near top
33)Which of the following is not a possible cause of short-circuiting in a pond?
a) Excessive weed growth
b) High influent BOD
c) Poor arrangement of inlet and outlet
d) Irregular pond bottom
b) High influent BOD
34)Common settling times in wastewater treatment plants range from
a) 15 to 30 minutes
b) 30 to 45 minutes
c) 1 to 2 hours
d) 2 to 4 hours
d) 2 to 4 hours
35)Which gas is produced in anaerobic digesters and can be used as a fuel?
a) Propane
b) Methane
c) Ethane
d) Carbon dioxide
e) Both a & b
b) Methane
36)Compute the lagoon’s approximate detention time in days. Information: Surface area = 6.0 acres
Average depth = 3.0 feet
average evaporation exceeds precipitation by 0.4 in/day Average daily flow(influent) = 0.25 MGD acre (area) = 43,560 sq. ft. 1 cu. Ft. contains 7.5 gal
a) 24
b) 32
c) 37
d) None of the above
a) 24
b) 32
c) 37
d) None of the above
find anser
37)How many pounds of chlorine gas is necessary to treat 4,000,000 gallons of wastewater at a dose of 2 mg/l? Formula
a) 61 lbs.
b) 65 lbs.
c) 67 lbs.
d) 69 lbs.
c) 67 lbs.
Formula = Pounds = flow (MGD) * mg/l * 8.34
(4,000,000 gal /1,000,000) * 2mg/l *8.34 = 66.7 lbs
38)Assume a community of 1,100 people has a lagoon. The flow averages 80,000 gallons per day.
The flow is
Formula
a) 14 gallons per capita.
b) 73 gallons per capita.
c) 80 gallons per capita.
d) 140 gallons per capita.
b) 73 gallons per capita.

80,000 gal / 1,100 people = 72.7 gallons per person
80,000 gal / 1,100 people = 72.7 gallons per person
39)The rock in most trickling filters is placed
a) Directly on the ground
b) Directly in a concrete slab
c) On a system of tile underdrains
d) On a rubber tile floor
a)Directly on the ground
b)Directly in a concrete slab
c)On a system of tile underdrains
d)On a rubber tile floor

find anser
40)Chlorine is used to
a) Disinfect
b) Prevent corrosion
c) Raise the pH
d) Stabilize organics
a) Disinfect
41)What is the purpose of heating and mixing a primary anaerobic digester?
a) To eliminate oxygen present
b) To increase the digestion rate
c) To keep methane gas in suspension
d) To prevent settling of grit to the bottom of the digester
e) a, b & c
b) To increase the digestion rate
42)The following device is used to measure the flow of wastewater:
a) Comminute
b) Comparator
c) Parshall flume
d) Sluice gate
c) Parshall flume
43)A spray nozzle on the mechanically cleaned screen has become plugged.
To ensure your safety, prior to entering the screen housing to repair the nozzle, you should
a)Leave a note on the breaker panel stating a repair is being made
b)Request assistance for the repair
c)Turn off and lock the motor control
d)Turn off local control switch.
c) Turn off and lock the motor control
44)Exhaust from a chlorinator room should be taken from
a)Anywhere the volume is important not the location
b)At floor level
c)Close to the entrance
d)In the ceiling
b) At floor level
45)Which of the following would be the safest action to take in the event of a major chlorine leak?
a)Call the fire department to hose down the chlorine container
b)Notify local police or sheriff
c)Roll the container so that liquid rather that gas escapes
d)Submerge the container in a basin or stream if feasible
b) Notify local police or sheriff
31)As water temperatures decrease, the disinfecting action of chlorine

a) Decreases

b) Increases

c) Remains the same
a) Decreases
32)The highest concentration of algae growth in a lagoon is usually observed
a) Near mid-depth
b) Near bottom
c) Near top
d) Below 10.0 feet
c) Near top
33)Which of the following is not a possible cause of short-circuiting in a pond?
a) Excessive weed growth
b) High influent BOD
c) Poor arrangement of inlet and outlet
d) Irregular pond bottom
b) High influent BOD
34)Common settling times in wastewater treatment plants range from
a) 15 to 30 minutes
b) 30 to 45 minutes
c) 1 to 2 hours
d) 2 to 4 hours
d) 2 to 4 hours
35)Which gas is produced in anaerobic digesters and can be used as a fuel?
a) Propane
b) Methane
c) Ethane
d) Carbon dioxide
e) Both a & b
b) Methane
36)Compute the lagoon’s approximate detention time in days.
Surface area = 6.0 acres
Average depth = 3.0 feet
average evaporation exceeds precipitation by 0.4 in/day Average daily flow (influent) = 0.25 MGD
1 acre (area) = 43,560 sq. ft
1 cu. Ft. contains 7.5 gal
a) 24
b) 32
c) 37
d) None of the above
a) 24
b) 32
c) 37
d) None of the above

find anser
37)How many pounds of chlorine gas is necessary to treat 4,000,000 gallons of wastewater at a dose of 2 mg/l?
a) 61 lbs.
b) 65 lbs.
c) 67 lbs.
d) 69 lbs.
c) 67 lbs.
Formula = Pounds = flow (MGD) * mg/l * 8.34
(4,000,000 gal /1,000,000) * 2mg/l *8.34 = 66.7 lbs
38)Assume a community of 1,100 people has a lagoon. The flow averages 80,000 gallons per day.
The flow is
Formula
a) 14 gallons per capita.
b) 73 gallons per capita.
c) 80 gallons per capita.
d) 140 gallons per capita.
b) 73 gallons per capita.

80,000 gal / 1,100 people = 72.7 gallons per person
80,000 gal / 1,100 people = 72.7 gallons per person
39)The rock in most trickling filters is placed
a) Directly on the ground
b) Directly in a concrete slab
c) On a system of tile underdrains
d) On a rubber tile floor
a)Directly on the ground
b)Directly in a concrete slab
c)On a system of tile underdrains
d)On a rubber tile floor

find anser
40)Chlorine is used to
a) Disinfect
b) Prevent corrosion
c) Raise the pH
d) Stabilize organics
a) Disinfect
41)What is the purpose of heating and mixing a primary anaerobic digester?
a) To eliminate oxygen present
b) To increase the digestion rate
c) To keep methane gas in suspension
d) To prevent settling of grit to the bottom of the digester
e) a, b & c
b) To increase the digestion rate
42)The following device is used to measure the flow of wastewater:
a) Comminute
b) Comparator
c) Parshall flume
d) Sluice gate
c) Parshall flume
43)A spray nozzle on the mechanically cleaned screen has become plugged.
To ensure your safety, prior to entering the screen housing to repair the nozzle, you should
a)Leave a note on the breaker panel stating a repair is being made
b)Request assistance for the repair
c)Turn off and lock the motor control
d)Turn off local control switch.
c) Turn off and lock the motor control
44)Exhaust from a chlorinator room should be taken from
a)Anywhere the volume is important not the location
b)At floor level
c)Close to the entrance
d)In the ceiling
b) At floor level
45)Which of the following would be the safest action to take in the event of a major chlorine leak?
a)Call the fire department to hose down the chlorine container
b)Notify local police or sheriff
c)Roll the container so that liquid rather that gas escapes
d)Submerge the container in a basin or stream if feasible
b) Notify local police or sheriff
46) A composite sample will give a (n)
a)even color
b)high pH.
c)Instantaneous sample.
d)Representative sample
d) Representative sample
47)Chlorine residual may be determined using the reagent
a)Diethyl-p-phenylenediamine (DPD)
b)Ethylendiamine tetraacetic acid (EDTA)
c)Poly chlorinated biphenyls (PCB)
d)Sodium thiosulfate (Na2 S2 O3)
a) Diethyl-p-phenylenediamine (DPD)
48)Results from the Multiple-Tube Fermentation Technique for members of the total Coliform Group are expressed as
a)DPD
b)MF
c)MGD
d)MPN
d) MPN
49)Drawings which are considered "As Built" would be
a)Construction drawings issued to the contractor.
b)Corrected construction drawings corrected to show changes made in the field installation.
c)Detailed drawings of the proposed construction.
d)Sectional maps on file.
b) Corrected construction drawings corrected to show changes made in the field installation
50)Sources for more information and training courses are
a)Federal, state and local water pollution control agencies.
b)Libraries.
c)Local and national water pollution control associations.
d)All of the above.
d) All of the above.
51) What test is not run on the influent
a)BOD
b)Fecal coliform
c)Suspended solids
d)pH
b) Fecal coliform
52) What disease is not considered to be normally conveyed or transmitted by untreated wastewater?
a)Amoebic dysentery
b)Hepatitis
c)Malaria
d)Cholera
c) Malaria
53) Pathogens
a)Are bacteria or virus that cause disease.
b)Are bacteria that do not occur in water.
c)Can obtain their food supply without help.
d)Are not harmful to man.
a) Are bacteria or virus that cause disease.
54) Improper handling, storage or preparing solutions of chemicals can cause
a)Burns
b)Explosions
c)Loss of eyesight
d)All of the above
d) All of the above
55) Considering the layout and flow diagram for the complete treatment plant, most oxidation ditch plants would be most similar to which of the following?
a)Completely mixed activated sludge
b)Contact stabilization
c)Conventional activated sludge
d)Plug flow aeration
a)Completely mixed activated sludge
b)Contact stabilization
c)Conventional activated sludge
d)Plug flow aeration

find anser
56) Over a four-year period, the hour meter on an instrument air compressor had the following readings at the end of each year:
1st year 976.3;
2nd year 1325.8
3rd year 2007.1
4th year 2371.4
How many hours does the meter show the compressor ran for the third year?
a)349.5 hours
b)364.3 hours
c)681.3 hours
d)830.2 hours
c) 681.3 hours

3rd year 2007.1 - 2nd year 1325.8 = 681.3
3rd year 2007.1 - 2nd year 1325.8 = 681.3
57) If a truck starting with a full tank of gasoline is driven 115 miles and you fill the truck with gasoline the following day and it requires 9.7 gallons to fill.
How many miles per gallon did the truck average?
a)9.2 miles per gallon.
b)11.8 miles per gallon.
c)17.6 miles per gallon.
d)20 miles per gallon
b) 11.8 miles per gallon
115 miles /9.7 gallons = 11.8 miles/gallon
58) An air-gap device is used to
a)Increase oxygen content in manholes
b)Prevent cross connections
c)Prevent excessive vibration in pipe joints
d)Aerate water
b) Prevent cross connections
59) A horizontal centrifugal pump has a rope packing. When the pump is operating, water slowly drips from the packing gland.This indicates that the
a)Packing bolts or nuts on the packing gland should be tightened
b)Packing bolts or nuts on the packing gland should be loosened
c)Packing bolts or nuts on the packing gland should be are properly adjusted
d)Packing should be replaced
c) Packing bolts or nuts on the packing gland should be are properly adjusted
60) Dresser and victaulic couplings are commonly used with what pipe materials?
a)Asbestos cement
b)Cast iron
c)Concrete
d)Plastic
b) Cast iron
61) If a fuse continues to blow, an operator should
a)Replace it with a higher capacity fuse
b)Provide a “jum[er” in the box
c)Inspect the affected equipment to determine the cause
d)Contact the power company to check for power surges
a) Replace it with a higher capacity fuse
b) Provide a “jum[er” in the box
c) Inspect the affected equipment to determine the cause
d) Contact the power company to check for power surges


find anser
62) A single piston reciprocating pump has a 6-inch diameter piston with a 6 inch length of stroke. If it makes 16 discharge strokes per minute, the pumping rate is __________ gallons per minute.
a) 6
b) 12
c) 25
d) 47
b) 12
1 foot =12 inches
Radius = ½ diameter
p =3.14
Volume of a cylinder = pR2h
Cubic foot = 7.48 gallons
6 inches * 1 foot = 0.5 foot diameter * 1 radius=0.25 feet radius
12 inches 2 diameter
3.14 * (0.25 ft * 0.25 ft) * 0.5 ft (height) = 0.098125 ft3 /per stroke
Formula

1 foot =12 inches

Radius = ½ diameter

p =3.14

Volume of a cylinder = pR2h

Cubic foot = 7.48 gallons





6 inches * 1 foot = 0.5 foot diameter * 1 radius = 0.25 feet radius

12 inches 2 diameter



3.14 * (0.25 ft * 0.25 ft) * 0.5 ft (height) = 0.098125 ft3 /per stroke
63) A fire hydrant should be closed slowly to avoid
a)Excessive head loss
b)Excessive Wear
c)Injury to the operator
d)Water hammer
d) Water hammer
64) In electrical circuits a(n) _________is used to reduce the voltage where necessary.
a) Ammeter
b) Thermal overload
c) Transformer
d) Voltmeter
c) Transformer
65) Wear rings are installed in a pump to
a)Hold the shaft in position
b)Keep the impeller in place
c)Concentrate wear on an economically replaceable part
d)Wear out rings instead of the sleeves
c) Concentrate wear on an economically replaceable part
66) Globe valves are used for all of the following purposes, except
a)Air-vacuum control
b)Flow regulation
c)Pressure regulation
d)Pump control
a)Air-vacuum control
b)Flow regulation
c)Pressure regulation
d)Pump control

find anser
67) A positive displacement sludge pump should never be placed into operation
a)Without being primed
b)With the discharge valve closed
c)With the discharge valve open
d)None of the above
b) With the discharge valve closed
68) Closing a valve too quickly causes
a)A surge in the line
b)No problems in the piping
c)Pipe fittings seat and become more secure
d)The wastewater goes septic
a) A surge in the line
69) What effect will the addition of chlorine, acid, alum, carbon dioxide, or sulfuric acid have on the pH of wastewater?
a)Neutralize
b)Lower
c)Increase
d)Have no effect
b) Lower
70) Given the data below, what is the most likely cause of the extended aeration facility problem?

Data: DO in aeration high
Sludge blanket in clarifier is high
Return sludge flow is low
Air control valve is open
Blower normal
a)Adjustable slot plate elevation too low
b)Returned sludge air lift is clogged
c)Scum ejector clogged
d)Sludge collector shear pin broke
b) Returned sludge air lift is clogged
71) In which of the following types of wastewater would setline occur most rapidly?
a)Cold wastewater
b)Turbulent wastewater
c)Septic wastewater
d)Strong wastewater
a) Cold wastewater
72) Settled activated sludge is generally ______ than raw sludge.
a)Thinner
b)Thicker
c)Saltier
d)Denser
e)Both b & d
a) Thinner
73) Which of the following operational controls are used in the activated sludge process?
a)Aeration, wasting, recirculation.
b)Loading rate, solids concentration, DO.
c)Recycling rate, blower speed, sludge age.
d)Sludge blanket depth, settleability, floc size.
b) Loading rate, solids concentration, DO.
74) Which of the follow is not biologically active in a lagoon?
a)Aerobic bacteria
b)Anaerobic bacteria
c)Algae
d)Fungi
d) Fungi
75) Under ice and snow cover, the BOD level in the ponds will normally.
a)Decrease rapidly
b)Decrease slowly
c)Increase slowly
d)Remain the same
c) Increase slowly
76) An amperometric titrater is used to measure
a)Alkalinity
b)Chlorine residual
c)Conductivity
d)COD
b) Chlorine residual
77) Chloramines are
a)Combine chlorine
b)Enzymes
c)Found in polluted air
d)Diffuser head settings
a) Combine chlorine
78) The rotational speed of the air driven rotating biological contactor (RBC) is controlled by
a)Air pressure
b)Air velocity
c)Air volume
d)Diffuser head setting
a) Air pressure
79) Which of the following conditions increases chlorine demand?
a)Alkalinity increases
b)Increase in organic matter
c)Increase in phosphate concentration
d)pH increase
b) Increase in organic matter
80) The purpose of adding sodium thiosulfate to a microbiological sample bottle is to
a)Extend the allowable holding time from 6 to 30 hours
b)React with nitrates that interfere with the MPN test
c)Remove any chlorine residual present
d)To ensure sterilization of the sample bottle
c) Remove any chlorine residual present
81) Which of the following conditions are normal conditions for a manual control gas chlorination process?
a)Lines free of ice
b)Pressure reading slowly decreasing
c)Rotometer float fluctuation over a range of ten pounds per 24 hours
d)Vacuum gauge fluctuation over a range of 10” Hg
a)Lines free of ice
b)Pressure reading slowly decreasing
c)Rotometer float fluctuation over a range of ten pounds per 24 hours
d)Vacuum gauge fluctuation over a range of 10” Hg
82) Calculate the weir loading for a sedimentation tank that has an outlet weir 480 ft. long and a flow of 5 MGD.
a)96 gpd/ft.
b)9600 gpd/ft.
c)9920 gpd/ft.
d)10,420 gpd/ft.
d) 10,420 gpd/ft.
1,000,000 gallon = MG
5 MG * 1,000,000 gallons = 5,000,000 gallons is the same as 5,000,000 gpd
5,000,000 gpd=10,420 gpd/ft 480 ft
1,000,000 gallon = MG



5 MG * 1,000,000 gallons = 5,000,000 gallons is the same as 5,000,000 gpd

d MG d





5,000,000 gpd = 10,420 gpd/ft

480 ft
83) A settling basin has a length of 60 ft., width of 20 ft., and a depth of 12 ft. At a flow rate of 6 mgd, What is the retention time of this basin?
a)15 minutes
b)26 minutes
c)1.1 hours
d)2.3 hours
c) 1.1 hours
Formulas
Length * width * depth = volume
1 ft3 = 7.48 gallons
1 day = 24 hours
60 ft * 20 ft * 12 ft = 14,400 ft3
14,400 ft3 * 7.48 gallons =107,712 gallons is the volume of the tank ft3
60 MG * 1,000,000 gallons =6,000,000 gallons flow into the basin 107,712 gallons*1 day*24 hours*60 minutes=25.9 minutes
6,000,000 gallons day 1 hour
Formulas

Length * width * depth = volume

1 ft3 = 7.48 gallons

1 day = 24 hours





60 ft * 20 ft * 12 ft = 14,400 ft3



14,400 ft3 * 7.48 gallons = 107,712 gallons is the volume of the tank

ft3



60 MG * 1,000,000 gallons = 6,000,000 gallons flow into the basin

d MG d



107,712 gallons * 1 day * 24 hours * 60 minutes = 25.9 minutes

6,000,000 gallons day 1 hour
84) Calculate the pounds of BOD per day entering the trickling filter.
Data: Raw wastewater flow is 1.5 MGD
Raw wastewater BODis 150 mg/l
There is a 30% reduction in BOD across the primary clarifiers.
a)560 lbs/day
b)870 lbs/day
c)880 lbs/day
d)1600 lbs/day
d)1310 lbs/day
Formula
Flow(mgd) * concentration (mg/l) * 8.34 = lbs/day
Note 70% of the BOD passes through the primary clarifiers
1.5 mgd * (0.7 * 150 mg/l) * 8.34 = 1314 lbs/day
Formula

Flow(mgd) * concentration (mg/l) * 8.34 = lbs/day

Note 70% of the BOD passes through the primary clarifiers



1.5 mgd * (0.7 * 150 mg/l) * 8.34 = 1314 lbs/day
86) How many pounds of chlorine will be used in one day if the flow is 700,000 gpd and a uniform dose of 1.2 mg/l is maintained.
a)7 lbs
b)15 lbs
c)22 lbs
d)26 lbs
a)7 lbs
Formula
Flow (mgd) * concentration (mg/l) * 8.34 = lbs
700,000 gallons * 1MG*1.2 mg/l * 8.34=7
1,000,000 gallons
Formula

Flow (mgd) * concentration (mg/l) * 8.34 = lbs



700,000 gallons * 1MG * 1.2 mg/l * 8.34 = 7

1,000,000 gallons
87) The main action of mixed media filter is
a)Straining
b)Disinfection
c)Coagulation
d)None of the above
a) Straining
88) Chlorine cylinders may be lifted using
a)Cables
b)Chains
c)Clamps
d)Ropes
c) Clamps
89) A chlorine leak can be detected by
a)An exolosimeter
b)Checking the leak gauge
c)Green or reddish deposits on metal
d)Spraying water on suspected leaks
c) Green or reddish deposits on metal
90) Failure of the chlorine solution pump would result in
a)A decrease in digester gas production
b)An increase in digester gas production
c)Lower effluent fecal coliform count
d)None of the above
d) None of the above
91) Appreciable quantities of septic sludge "burping" to the surface of a primary settling tanks may indicate
a)Excessive activity of worms in the sludge settling tank
b)Excessive sludge scraper speed
c)Grit chambers are not properly removing grit
d)Sludge is not being pumped in sufficient quantities
d) Sludge is not being pumped in sufficient quantities
92) Not supplying enough air will cause
a)Effluent quality to improve
b)Excessive turbulence to occur on aeration compartment surface
c)Slick spots to show up on aeration compartment walkways
d)Turbidity of final effluent to increase
d) Turbidity of final effluent to increase
93) Given the data below what is the most likely cause of the extended aeration facility problem?
Data: DO level high
Blower normal
Wastewater characteristics normal. Drop pipe air control valve open
Surface turbulence high
a)Air relief valve stuck shut.
b)Blower speed too fast
c)Blower speed too slow
d)Drop pipe air control valves not open far enough
b) Blower speed too fast
94) If the sludge depth in a secondary sedimentation tank is too high, what will happen?
a)Decrease in turbidity in the effluent.
b)Returned activated sludge will have a lower oxygen demand.
c)Settleable solids from the aeration tank will increase.
d)Sludge may become septic.
d) Sludge may become septic
95) What might cause a white filamentous growth in a RBC system which will result in poor BOD removal efficiency?
a)High pH in the wastewater.
b)Low BOD loading.
c)Low pH in the Wastewater.
d)Septic wastewater.
d) Septic wastewater.
96) Pump station maintenance reports should include.
a)Additional maintenance scheduling required.
b)How repairs were made.
c)Special equipment required.
d)All of the above.
d) All of the above.
97) Disaster planning is
a)Having manuals ready so they can be read if a disaster occurs.
b)Something that, if properly done, will not need to be revised.
c)Useful in reducing confusion in the event of a disaster.
d)None of the above
c) Useful in reducing confusion in the event of a disaster.
98) Every day the operator of a small wastewater treatment plant should
a)Clean settling basins and dispose of sludge.
b)Determine that all the plant equipment is operational.
c)Replenish chemical stock.
d)Test start standby pimps, motors and generators.
b) Determine that all the plant equipment is operational.
99) There are generally more limitations on authority the farther one __________ in the organization.
a)Ascends
b)Descends
c)Moves horizontally
d)Remains
b) Descends
100) When an employee breaks the rules and requires discipline, who generally is responsible for administering it?
a)Fellow employee.
b)Personnel office.
c)Supervisor.
d)Upper management.
c) Supervisor