Page 1 of 34
WASTEWATER TREATMENT OPERATOR
CERTIFICATION TEST 2 EXAM NEWEST 2026
ACTUAL EXAM QUESTIONS AND CORRECT
DETAILED ANSWERS (VERIFIED ANSWERS) ALL
ANSWERED {80 Q & A} ALREADY GRADED A+ |
BRAND NEW! | 100% GUARANTEED PASS
What is accomplished by the activated sludge process?
A) Anaerobic bacteria use SO_4 to eat incoming volatile solids
B) Remove soluble or finely divided suspended materials
C) Anoxic microorganisms destroy incoming BOD
D) Zoogleal breaks down influent organics - ✔✔✔ Correct Answer > B)
Remove soluble or finely divided suspended materials (v.2 pg 16)
What should be done to find a small chlorine leak?
A) Spray hypocloric acid near the suspected leak
B) Tie a rag on a stick, dip the rag in a strong ammonia solution,
and hold the rag near the suspected points
C) Release carbon dioxide to trace the leak
,Page 2 of 34
D) Apply a small quantity of citric acid near the leak - ✔✔✔ Correct
Answer > B) Tie a rag on a stick, dip the rag in a strong ammonia
solution, and hold the rag near the suspected points (v.1 pg 386)
What are colloids?
A) Solids that settle rapidly
B) Dissolved solids
C) Solids found in the grit channel
D) Very small, finely divided solids that remain dispersed in a
liquid for a long time - ✔✔✔ Correct Answer > D) Very small, finely
divided solids that remain dispersed in a liquid for a long time (v.1
pg 22,144)
What is sludge bulking in an activated sludge process?
A) When mixed liquor solids settle slowly and compact to a
limited extent
B) When old sludge denitrify and cause sludge to rise as a result
of gastrification
C) When sludge form large aggregates and cause sludge to settle
quickly
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D) When compaction in the secondary clarifier is improved due to
chemical injection - ✔✔✔ Correct Answer > A) When mixed liquor
solids settle slowly and compact to a limited extent (v.2 pg 71)
Which of the following is a collection of individual samples
obtained at regular intervals?
A) Grab
B) Culmination
C) Comprehensive
D) Composite - ✔✔✔ Correct Answer > D) Composite (v.2 pg 499)
What is the most common imbalance in an anaerobic digester?
A) Excess methane formation
B) Excess nitrogen formation
C) Excess acid formation
D) Excess carbon dioxide formation - ✔✔✔ Correct Answer > C) Excess
acid formation (v.2 pg 148)
What is the carbon dioxide content of a properly functioning
anaerobic digester?
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A) 65 to 70% by volume
B) 1 to 2% by volume
C) 30 to 35% by volume
D) 40 to 60% by volume - ✔✔✔ Correct Answer > C) 30 to 35% by
volume (v.2 pg 158)
What is the most common piece of laboratory equipment, which
is used mainly to mix chemicals and measure approximate
volumes?
A) Beaker
B) Graduated cylinder
C) Pipet
D) Flask - ✔✔✔ Correct Answer > A) Beaker(v.2 pg 479)
What is the most common type of grit collector?
A) Deflectors
B) Weirs
C) Chain driven scrapers called "flights"
D) Parshall flume - ✔✔✔ Correct Answer > C) Chain driven scrapers
called "flights" (v.1 pg 87)
WASTEWATER TREATMENT OPERATOR
CERTIFICATION TEST 2 EXAM NEWEST 2026
ACTUAL EXAM QUESTIONS AND CORRECT
DETAILED ANSWERS (VERIFIED ANSWERS) ALL
ANSWERED {80 Q & A} ALREADY GRADED A+ |
BRAND NEW! | 100% GUARANTEED PASS
What is accomplished by the activated sludge process?
A) Anaerobic bacteria use SO_4 to eat incoming volatile solids
B) Remove soluble or finely divided suspended materials
C) Anoxic microorganisms destroy incoming BOD
D) Zoogleal breaks down influent organics - ✔✔✔ Correct Answer > B)
Remove soluble or finely divided suspended materials (v.2 pg 16)
What should be done to find a small chlorine leak?
A) Spray hypocloric acid near the suspected leak
B) Tie a rag on a stick, dip the rag in a strong ammonia solution,
and hold the rag near the suspected points
C) Release carbon dioxide to trace the leak
,Page 2 of 34
D) Apply a small quantity of citric acid near the leak - ✔✔✔ Correct
Answer > B) Tie a rag on a stick, dip the rag in a strong ammonia
solution, and hold the rag near the suspected points (v.1 pg 386)
What are colloids?
A) Solids that settle rapidly
B) Dissolved solids
C) Solids found in the grit channel
D) Very small, finely divided solids that remain dispersed in a
liquid for a long time - ✔✔✔ Correct Answer > D) Very small, finely
divided solids that remain dispersed in a liquid for a long time (v.1
pg 22,144)
What is sludge bulking in an activated sludge process?
A) When mixed liquor solids settle slowly and compact to a
limited extent
B) When old sludge denitrify and cause sludge to rise as a result
of gastrification
C) When sludge form large aggregates and cause sludge to settle
quickly
,Page 3 of 34
D) When compaction in the secondary clarifier is improved due to
chemical injection - ✔✔✔ Correct Answer > A) When mixed liquor
solids settle slowly and compact to a limited extent (v.2 pg 71)
Which of the following is a collection of individual samples
obtained at regular intervals?
A) Grab
B) Culmination
C) Comprehensive
D) Composite - ✔✔✔ Correct Answer > D) Composite (v.2 pg 499)
What is the most common imbalance in an anaerobic digester?
A) Excess methane formation
B) Excess nitrogen formation
C) Excess acid formation
D) Excess carbon dioxide formation - ✔✔✔ Correct Answer > C) Excess
acid formation (v.2 pg 148)
What is the carbon dioxide content of a properly functioning
anaerobic digester?
, Page 4 of 34
A) 65 to 70% by volume
B) 1 to 2% by volume
C) 30 to 35% by volume
D) 40 to 60% by volume - ✔✔✔ Correct Answer > C) 30 to 35% by
volume (v.2 pg 158)
What is the most common piece of laboratory equipment, which
is used mainly to mix chemicals and measure approximate
volumes?
A) Beaker
B) Graduated cylinder
C) Pipet
D) Flask - ✔✔✔ Correct Answer > A) Beaker(v.2 pg 479)
What is the most common type of grit collector?
A) Deflectors
B) Weirs
C) Chain driven scrapers called "flights"
D) Parshall flume - ✔✔✔ Correct Answer > C) Chain driven scrapers
called "flights" (v.1 pg 87)
