SEWAGE TREATMENT EXAM 2025 QUESTIONS WITH
ANSWERS RATED A+
✔✔Conventional systems - ✔✔Wastewater treatment systems that have been
traditionally used to collect municipal wastewater in sewers and convey it to a central
facility for treatment prior to discharge to surface waters; either primary or secondary
treatment may be provided
✔✔Denitrification - ✔✔The reduction of nitrite to nitrogen gas; carried out in wastewater
treatment tanks by bacteria under anoxic conditions, i.e. anaerobic respiration by
facultative anaerobes like Pseudomonas spp.
✔✔Diffused air - ✔✔A technique by which air under pressure is forced into sewage in
an aeration tank; the air is pumped into the tank through a perforated pipe and moves
as bubbles through the sewage
✔✔Digestion - ✔✔Takes place in tanks where volatile organic materials are
decomposed by bacteria, resulting in partial gasification, liquefaction, and mineralization
of pollutants
✔✔Disinfection - ✔✔The killing of pathogenic microbes including pathogenic bacteria,
viruses, helminths, and protozoans
✔✔Dispersal/percolation - ✔✔Involves a volume of wastewater applied to the land,
penetrating the surface, and passing through the underlying soil
✔✔Dissolved oxygen - ✔✔The amount of free oxygen in solution in water, or
wastewater effluent; adequate concentrations are necessary for fish and other aquatic
organisms to live and to prevent offensive odors
✔✔Eligible costs - ✔✔Wastewater reduction activities that can be funded with State
Revolving Fund (SRF) loans
✔✔Effluent - ✔✔The treated liquid that comes out of a treatment plant after completion
of the treatment process
✔✔Eutrophication - ✔✔The normally slow aging process by which a lake evolves into a
bog or marsh and ultimately disappears; the lake becomes enriched with nutrients,
especially nitrogen and phosphorus, which support the excess production of algae and
other aquatic plant life; may be accelerated by many human activities
✔✔Evapotranspiration - ✔✔The uptake of water from the soil by evaporation and by
transpiration from the plants growing thereon
, ✔✔Floc - ✔✔A clump of solids formed in sewage by biological or chemical action
✔✔Flocculation - ✔✔The process by which clumps of solids in sewage are made to
increase in size by chemical action
✔✔Gray water - ✔✔Refers to domestic wastewater composed of wash water from
sinks, shower, washing machines
✔✔Grinder pump - ✔✔A mechanical device which shreds wastewater solids and raises
the fluid pressure level high enough to pass wastewater through small diameter
pressure sewers
✔✔Grit chamber - ✔✔A small detention basin designed to permit the settling of coarse,
heavy inorganic solids, such as sand, while allowing the lighter organic solids to pass
through the chamber
✔✔Groundwater - ✔✔The zone beneath the ground surface saturated with water that
has seeped down through soil and rock
✔✔Impervious - ✔✔Resistant to penetration by fluids or by roots
✔✔Incineration - ✔✔Involves combustion of the organic matter in sewage sludge,
producing a residual inert ash
✔✔Infiltration - ✔✔The penetration of water through the ground into sub-surface soil or
the passing of water from the soil into a pipe, such as a sewer
✔✔Influent - ✔✔Refers to water, wastewater, or other liquid flowing into a reservoir,
basin or treatment plant, or any unit thereof
✔✔Inorganic - ✔✔Refers to compounds that do not contain carbon
✔✔Interceptors - ✔✔Large sewer lines that collect the flows from smaller main and
trunk sewers and carry them to the treatment plant
✔✔Intermittent sand filter - ✔✔Involves a bed of sand or other fine-grained material to
which wastewater is applied intermittently in flooding doses
✔✔Lagoon - ✔✔A shallow pond in which algae, aerobic and anaerobic bacterial purify
wastewater
✔✔Land application - ✔✔The controlledapplication of wastewater or biosolids onto the
ground for treatment and/or reuse
ANSWERS RATED A+
✔✔Conventional systems - ✔✔Wastewater treatment systems that have been
traditionally used to collect municipal wastewater in sewers and convey it to a central
facility for treatment prior to discharge to surface waters; either primary or secondary
treatment may be provided
✔✔Denitrification - ✔✔The reduction of nitrite to nitrogen gas; carried out in wastewater
treatment tanks by bacteria under anoxic conditions, i.e. anaerobic respiration by
facultative anaerobes like Pseudomonas spp.
✔✔Diffused air - ✔✔A technique by which air under pressure is forced into sewage in
an aeration tank; the air is pumped into the tank through a perforated pipe and moves
as bubbles through the sewage
✔✔Digestion - ✔✔Takes place in tanks where volatile organic materials are
decomposed by bacteria, resulting in partial gasification, liquefaction, and mineralization
of pollutants
✔✔Disinfection - ✔✔The killing of pathogenic microbes including pathogenic bacteria,
viruses, helminths, and protozoans
✔✔Dispersal/percolation - ✔✔Involves a volume of wastewater applied to the land,
penetrating the surface, and passing through the underlying soil
✔✔Dissolved oxygen - ✔✔The amount of free oxygen in solution in water, or
wastewater effluent; adequate concentrations are necessary for fish and other aquatic
organisms to live and to prevent offensive odors
✔✔Eligible costs - ✔✔Wastewater reduction activities that can be funded with State
Revolving Fund (SRF) loans
✔✔Effluent - ✔✔The treated liquid that comes out of a treatment plant after completion
of the treatment process
✔✔Eutrophication - ✔✔The normally slow aging process by which a lake evolves into a
bog or marsh and ultimately disappears; the lake becomes enriched with nutrients,
especially nitrogen and phosphorus, which support the excess production of algae and
other aquatic plant life; may be accelerated by many human activities
✔✔Evapotranspiration - ✔✔The uptake of water from the soil by evaporation and by
transpiration from the plants growing thereon
, ✔✔Floc - ✔✔A clump of solids formed in sewage by biological or chemical action
✔✔Flocculation - ✔✔The process by which clumps of solids in sewage are made to
increase in size by chemical action
✔✔Gray water - ✔✔Refers to domestic wastewater composed of wash water from
sinks, shower, washing machines
✔✔Grinder pump - ✔✔A mechanical device which shreds wastewater solids and raises
the fluid pressure level high enough to pass wastewater through small diameter
pressure sewers
✔✔Grit chamber - ✔✔A small detention basin designed to permit the settling of coarse,
heavy inorganic solids, such as sand, while allowing the lighter organic solids to pass
through the chamber
✔✔Groundwater - ✔✔The zone beneath the ground surface saturated with water that
has seeped down through soil and rock
✔✔Impervious - ✔✔Resistant to penetration by fluids or by roots
✔✔Incineration - ✔✔Involves combustion of the organic matter in sewage sludge,
producing a residual inert ash
✔✔Infiltration - ✔✔The penetration of water through the ground into sub-surface soil or
the passing of water from the soil into a pipe, such as a sewer
✔✔Influent - ✔✔Refers to water, wastewater, or other liquid flowing into a reservoir,
basin or treatment plant, or any unit thereof
✔✔Inorganic - ✔✔Refers to compounds that do not contain carbon
✔✔Interceptors - ✔✔Large sewer lines that collect the flows from smaller main and
trunk sewers and carry them to the treatment plant
✔✔Intermittent sand filter - ✔✔Involves a bed of sand or other fine-grained material to
which wastewater is applied intermittently in flooding doses
✔✔Lagoon - ✔✔A shallow pond in which algae, aerobic and anaerobic bacterial purify
wastewater
✔✔Land application - ✔✔The controlledapplication of wastewater or biosolids onto the
ground for treatment and/or reuse
