Wastewater Operator certification -Grade 2 UPDATED ACTUAL
Questions and CORRECT Answers
Question: General Wastewater Treatment
Correct Answer: What is the pressure head caused by?: Water elevation
Question: General Wastewater Treatment
Correct Answer: What color should the piping be that contains reclaimed water?: purple
Question: General Wastewater Treatment
Correct Answer: What is the term for the height to which a column of water will rise in a well.:
piezometric surface
Question: General Wastewater Treatment
Correct Answer: In general, what is the maximum practical lift of pumps: 15-25ft
Question: General Wastewater Treatment
Correct Answer: Which one of the following valves is the best to use in throttling a flow situation? a. gate
b. butterfly c. globe d. ball: globe
Question: General Wastewater Treatment
Correct Answer: Which one of the following devices is used to measure water depths in storage facilities?
a. transducer b. Venturi meter c. magnetic sensor d. thermistor: transducer
Question: Wastewater Treatment Facilities
Correct Answer: The velocity in sanitary sewers is approximately:: 2 ft/s
Question: Wastewater Treatment Facilities
Correct Answer: The distance between manholes ranges from: 300-500ft
Question: Wastewater Treatment Facilities
Correct Answer: What should the flow velocity be through a grit channel: 1.0 ft/s
Question: Wastewater Treatment Facilities
Correct Answer: Grit washers are used to______ a. remove some of the organic matter b. remove large
pieces of wood c. remove rags and eggshells d. remove the odors: remove some of the organic matter
Question: Wastewater Treatment Facilities
Correct Answer: The most common flow-measure device for wastewater is a_____: parshall flume
Question: Wastewater Treatment Facilities
Correct Answer: The detention time for primary clarifiers usually has a range of_____hr/s: 1.5-2hr
Question: Wastewater Treatment Facilities
Correct Answer: The effluent from which process is called mixed liquor a.secondary clarification b.
primary clarification c. sludge drying bed or pond d. activated sludge: activated sludge
Question: Wastewater Treatment Facilities
,Correct Answer: Aerobic ponds usually range in depth from ___-____ft: 3-6ft
Question: Wastewater Treatment Facilities
Correct Answer: Anaerobic ponds usually range in depth from___-___ft: 8-12ft
Question: Wastewater Treatment Facilities
Correct Answer: Another name for a waste stabilization pond is: raw wastewater lagoon
Question: Wastewater sources & characteristics
Correct Answer: Typically what average percent of total solids in a domestic wastewater, both dissolved
and suspended, are inorganics: 50%
Question: Wastewater sources & characteristics
Correct Answer: Typically, what average percent of total solids in domestic wastewater, both dissolved
and suspended, are inorganics?: 50%
Question: Wastewater sources & characteristics
Correct Answer: Approx. what % of the dissolved solids in wastewater are inorganics: 87%
Question: Wastewater sources & characteristics
Correct Answer: Approximately what % of the dissolved solids in wastewater are organics: 12%
Question: Wastewater sources & characteristics
Correct Answer: Which organism wold most probably be associated with moderate sludge age and
effluent water quality: free-swimming ciliates
Question: Wastewater sources & characteristics
Correct Answer: Which organism would most probably be associated with high suspended solids and
biochemical oxygen demand (BOD): amoebas
Question: Wastewater sources & characteristics
Correct Answer: High suspended solids and BOD are most probably associated with which type of
organisms?: flagellates
Question: Wastewater sources & characteristics
Correct Answer: What organism would most likely enhance the penetration of oxygen into the activated
sludge: rotifers
Question: Rocks/Screens/Comminutors & Grit Removal
Correct Answer: Chlorine gas has a specific gravity of: 2.5 specific gravity
Question: Rocks/Screens/Comminutors & Grit Removal
Correct Answer: Proper flow velocity through a grit channel is indicated when the grit being removed
contains a. no organics b. a little organic material c. about half the volume as the grit being removed d.
about the same volume as the grit being removed: a little organic material
Question: Sedimentation and Flotation
Correct Answer: Surface loading and detention time is a clarifier are directly related to:: flow through a
clarifier
, Question: Sedimentation and Flotation
Correct Answer: What is the expected range for the removal of settleable solids from a primary clarifier?:
95-99%
Question: Sedimentation and Flotation
Correct Answer: What condition will occur if sludge is not pumped out of primary clarifiers at regular
intervals?: clarifier will become septic
Question: Sedimentation and Flotation
Correct Answer: Secondary clarifiers are usually located after: a. primary clarifier b. an anaerobic digester
c. a biological process d. preaeration: a biological process
Question: Sedimentation and Flotation
Correct Answer: Filter sloughings are a product of:: biological action
Question: Sedimentation and Flotation
Correct Answer: when one liquid is dissolved in another liquid it is called: an emulsion
Question: Sedimentation and Flotation
Correct Answer: What is the optimum temperature for digester substances?: 90 degrees F
Question: Secondary Treatment
Correct Answer: Which one of the following types of wastewater ponds listed below is not classified like
the other three? a. polishing pond 2. oxidation pond c. aerobic pond d. raw sewage: aerobic pond
Question: Secondary Treatment
Correct Answer: What type of pond would receive wastewater form a secondary treatment system?:
polishing pond
Question: Secondary Treatment
Correct Answer: The color of the bio-film on a rotating biological contactor undergoing nitrification
would appear?: reddish brown to golden
Question: Secondary Treatment
Correct Answer: The color of the bio-film on a rotating biological contactor that has high sulfur
concentrations would appear: chalky white
Question: Secondary Treatment
Correct Answer: Rotating biological contactors have all the following advantages except: a. high sludge
production b. they can handle a large range of flows c. power requirements are low d. low operating costs,
as they are east to run: high sludge production
Question: Secondary Treatment
Correct Answer: A wastewater [plant has a train of three rotating biological contactor (RBC) units. The
color of the first RBC is___; the color of the second RBC is_____; and the color of the third RBS C is____:
(1) gray (2) reddish brown (3) reddish brown
Question: Activated Sludge
Questions and CORRECT Answers
Question: General Wastewater Treatment
Correct Answer: What is the pressure head caused by?: Water elevation
Question: General Wastewater Treatment
Correct Answer: What color should the piping be that contains reclaimed water?: purple
Question: General Wastewater Treatment
Correct Answer: What is the term for the height to which a column of water will rise in a well.:
piezometric surface
Question: General Wastewater Treatment
Correct Answer: In general, what is the maximum practical lift of pumps: 15-25ft
Question: General Wastewater Treatment
Correct Answer: Which one of the following valves is the best to use in throttling a flow situation? a. gate
b. butterfly c. globe d. ball: globe
Question: General Wastewater Treatment
Correct Answer: Which one of the following devices is used to measure water depths in storage facilities?
a. transducer b. Venturi meter c. magnetic sensor d. thermistor: transducer
Question: Wastewater Treatment Facilities
Correct Answer: The velocity in sanitary sewers is approximately:: 2 ft/s
Question: Wastewater Treatment Facilities
Correct Answer: The distance between manholes ranges from: 300-500ft
Question: Wastewater Treatment Facilities
Correct Answer: What should the flow velocity be through a grit channel: 1.0 ft/s
Question: Wastewater Treatment Facilities
Correct Answer: Grit washers are used to______ a. remove some of the organic matter b. remove large
pieces of wood c. remove rags and eggshells d. remove the odors: remove some of the organic matter
Question: Wastewater Treatment Facilities
Correct Answer: The most common flow-measure device for wastewater is a_____: parshall flume
Question: Wastewater Treatment Facilities
Correct Answer: The detention time for primary clarifiers usually has a range of_____hr/s: 1.5-2hr
Question: Wastewater Treatment Facilities
Correct Answer: The effluent from which process is called mixed liquor a.secondary clarification b.
primary clarification c. sludge drying bed or pond d. activated sludge: activated sludge
Question: Wastewater Treatment Facilities
,Correct Answer: Aerobic ponds usually range in depth from ___-____ft: 3-6ft
Question: Wastewater Treatment Facilities
Correct Answer: Anaerobic ponds usually range in depth from___-___ft: 8-12ft
Question: Wastewater Treatment Facilities
Correct Answer: Another name for a waste stabilization pond is: raw wastewater lagoon
Question: Wastewater sources & characteristics
Correct Answer: Typically what average percent of total solids in a domestic wastewater, both dissolved
and suspended, are inorganics: 50%
Question: Wastewater sources & characteristics
Correct Answer: Typically, what average percent of total solids in domestic wastewater, both dissolved
and suspended, are inorganics?: 50%
Question: Wastewater sources & characteristics
Correct Answer: Approx. what % of the dissolved solids in wastewater are inorganics: 87%
Question: Wastewater sources & characteristics
Correct Answer: Approximately what % of the dissolved solids in wastewater are organics: 12%
Question: Wastewater sources & characteristics
Correct Answer: Which organism wold most probably be associated with moderate sludge age and
effluent water quality: free-swimming ciliates
Question: Wastewater sources & characteristics
Correct Answer: Which organism would most probably be associated with high suspended solids and
biochemical oxygen demand (BOD): amoebas
Question: Wastewater sources & characteristics
Correct Answer: High suspended solids and BOD are most probably associated with which type of
organisms?: flagellates
Question: Wastewater sources & characteristics
Correct Answer: What organism would most likely enhance the penetration of oxygen into the activated
sludge: rotifers
Question: Rocks/Screens/Comminutors & Grit Removal
Correct Answer: Chlorine gas has a specific gravity of: 2.5 specific gravity
Question: Rocks/Screens/Comminutors & Grit Removal
Correct Answer: Proper flow velocity through a grit channel is indicated when the grit being removed
contains a. no organics b. a little organic material c. about half the volume as the grit being removed d.
about the same volume as the grit being removed: a little organic material
Question: Sedimentation and Flotation
Correct Answer: Surface loading and detention time is a clarifier are directly related to:: flow through a
clarifier
, Question: Sedimentation and Flotation
Correct Answer: What is the expected range for the removal of settleable solids from a primary clarifier?:
95-99%
Question: Sedimentation and Flotation
Correct Answer: What condition will occur if sludge is not pumped out of primary clarifiers at regular
intervals?: clarifier will become septic
Question: Sedimentation and Flotation
Correct Answer: Secondary clarifiers are usually located after: a. primary clarifier b. an anaerobic digester
c. a biological process d. preaeration: a biological process
Question: Sedimentation and Flotation
Correct Answer: Filter sloughings are a product of:: biological action
Question: Sedimentation and Flotation
Correct Answer: when one liquid is dissolved in another liquid it is called: an emulsion
Question: Sedimentation and Flotation
Correct Answer: What is the optimum temperature for digester substances?: 90 degrees F
Question: Secondary Treatment
Correct Answer: Which one of the following types of wastewater ponds listed below is not classified like
the other three? a. polishing pond 2. oxidation pond c. aerobic pond d. raw sewage: aerobic pond
Question: Secondary Treatment
Correct Answer: What type of pond would receive wastewater form a secondary treatment system?:
polishing pond
Question: Secondary Treatment
Correct Answer: The color of the bio-film on a rotating biological contactor undergoing nitrification
would appear?: reddish brown to golden
Question: Secondary Treatment
Correct Answer: The color of the bio-film on a rotating biological contactor that has high sulfur
concentrations would appear: chalky white
Question: Secondary Treatment
Correct Answer: Rotating biological contactors have all the following advantages except: a. high sludge
production b. they can handle a large range of flows c. power requirements are low d. low operating costs,
as they are east to run: high sludge production
Question: Secondary Treatment
Correct Answer: A wastewater [plant has a train of three rotating biological contactor (RBC) units. The
color of the first RBC is___; the color of the second RBC is_____; and the color of the third RBS C is____:
(1) gray (2) reddish brown (3) reddish brown
Question: Activated Sludge
