WI DNR Wastewater Operator
Certification (General) fully solved
Which provides a better composite representative:
A. A smaller sample collected more often
B. A larger sample collected less often - correct answer ✔✔A smaller sample collected more
often
Which part of the treatment process uses biological processes?
A: Primary
B: Secondary
C: Tertiary
D: WAS - correct answer ✔✔Secondary
The activated sludge (bio mass) collected in the final clarifier and returned to the secondary
treatment process to mix with the incoming wastewater is:
A: Mixed Liquor Suspended Solids (MLSS)
B: Waste Activated Sludge (WAS)
C: Return Activated Sludge (RAS)
D: Mixed Liquor Volatile Suspended Solids (MLSS) - correct answer ✔✔Return Activated Sludge
(RAS)
Define primary treatment - correct answer ✔✔Clarification by solid and liquid separation that
removes a substantial amount of suspended and floating matter.
,True or False: Disinfection destroys all microorganisms? - correct answer ✔✔False
What type of solids does a clarifier remove? - correct answer ✔✔Floating and settled
Define F:M using BOD and MLSS - correct answer ✔✔F:M is the food:microorganism ratio
where the 'food' is BOD and the microorganisms are the MLSS/MLVSS.
What is a restriction in an open channel used to measure flow?
A: Weir
B: Box cord
C: Packing
D: Flume - correct answer ✔✔Flume
What is a selector? - correct answer ✔✔Part of the treatment system that selects a specific type
of organism by providing an environment (Anaerobic, anoxic, or aerobic) that favors its growth.
_____ are flows generated within the plant, usually from solids processing that has been
recycled back through the plant. - correct answer ✔✔Sidestreams
_____ is the treatment process that uses physical, chemical, or biological processes to remove
suspended solids and nutrients in wastewater to accomplish a level of treatment greater than
what can be accomplished by secondary treatment.
A: Primary treatment
B: Disinfection
C: Tertiary treatment
D: Sour treatment - correct answer ✔✔Tertiary treatment
, The activated sludge (except biomass or cell mass) removed from the secondary treatment
process.
A: Mixed Liquor Suspended Solids (MLSS)
B: Waste Activated Sludge (WAS)
C: Return Activated Sludge (RAS)
D: Mixed Liquor Volatile Suspended Solids (MLSS) - correct answer ✔✔Waste Activated Sludge
(WAS)
What are the two main reasons for treating wastewater? - correct answer ✔✔To protect public
health by destroying pathogens and to protect the environment by removing pollutants.
Discuss the effect of I&I on a collection system - correct answer ✔✔(1)Exceed capacity of the
pipes = sanitary sewer overflows (SSO).
(2) Very high flows entering the treatment facility can lead to too much flow going through
aeration basins and clarifiers washing out solids, creating a loss of treatment efficiency
A structure that allows a pipe to dip below an obstruction by forming a "U" shaped path. Liquid
flowing in one end is forced up and out the over. It is typically used in collections when there is a
river or other deep obstructions.
A: Gate Valve Structure
B: Torque Wrench
C: Pathfinder
D: Inverted Siphon - correct answer ✔✔Inverted Siphon
Fill in the general characteristics for domestic wastewater: (mg/L)
Certification (General) fully solved
Which provides a better composite representative:
A. A smaller sample collected more often
B. A larger sample collected less often - correct answer ✔✔A smaller sample collected more
often
Which part of the treatment process uses biological processes?
A: Primary
B: Secondary
C: Tertiary
D: WAS - correct answer ✔✔Secondary
The activated sludge (bio mass) collected in the final clarifier and returned to the secondary
treatment process to mix with the incoming wastewater is:
A: Mixed Liquor Suspended Solids (MLSS)
B: Waste Activated Sludge (WAS)
C: Return Activated Sludge (RAS)
D: Mixed Liquor Volatile Suspended Solids (MLSS) - correct answer ✔✔Return Activated Sludge
(RAS)
Define primary treatment - correct answer ✔✔Clarification by solid and liquid separation that
removes a substantial amount of suspended and floating matter.
,True or False: Disinfection destroys all microorganisms? - correct answer ✔✔False
What type of solids does a clarifier remove? - correct answer ✔✔Floating and settled
Define F:M using BOD and MLSS - correct answer ✔✔F:M is the food:microorganism ratio
where the 'food' is BOD and the microorganisms are the MLSS/MLVSS.
What is a restriction in an open channel used to measure flow?
A: Weir
B: Box cord
C: Packing
D: Flume - correct answer ✔✔Flume
What is a selector? - correct answer ✔✔Part of the treatment system that selects a specific type
of organism by providing an environment (Anaerobic, anoxic, or aerobic) that favors its growth.
_____ are flows generated within the plant, usually from solids processing that has been
recycled back through the plant. - correct answer ✔✔Sidestreams
_____ is the treatment process that uses physical, chemical, or biological processes to remove
suspended solids and nutrients in wastewater to accomplish a level of treatment greater than
what can be accomplished by secondary treatment.
A: Primary treatment
B: Disinfection
C: Tertiary treatment
D: Sour treatment - correct answer ✔✔Tertiary treatment
, The activated sludge (except biomass or cell mass) removed from the secondary treatment
process.
A: Mixed Liquor Suspended Solids (MLSS)
B: Waste Activated Sludge (WAS)
C: Return Activated Sludge (RAS)
D: Mixed Liquor Volatile Suspended Solids (MLSS) - correct answer ✔✔Waste Activated Sludge
(WAS)
What are the two main reasons for treating wastewater? - correct answer ✔✔To protect public
health by destroying pathogens and to protect the environment by removing pollutants.
Discuss the effect of I&I on a collection system - correct answer ✔✔(1)Exceed capacity of the
pipes = sanitary sewer overflows (SSO).
(2) Very high flows entering the treatment facility can lead to too much flow going through
aeration basins and clarifiers washing out solids, creating a loss of treatment efficiency
A structure that allows a pipe to dip below an obstruction by forming a "U" shaped path. Liquid
flowing in one end is forced up and out the over. It is typically used in collections when there is a
river or other deep obstructions.
A: Gate Valve Structure
B: Torque Wrench
C: Pathfinder
D: Inverted Siphon - correct answer ✔✔Inverted Siphon
Fill in the general characteristics for domestic wastewater: (mg/L)
