TCEQ WASTEWATER COLLECTION
SYSTEM OPERATOR CLASS I —
FORM C EXAM QUESTIONS WITH
CORRECT ANSWERS PLUS
RATIONALES 2026/2027 EDITION
WITH INSTANT PDF DOWNLOAD.
Question 1
What is the primary purpose of a wastewater collection system?
A. To disinfect drinking water
B. To produce potable water
C. To collect and convey wastewater to a treatment facility
D. To increase groundwater recharge
Rationale: A wastewater collection system is designed to receive
wastewater from homes, businesses, and other sources and
convey it safely to a treatment facility. Its fundamental function is
collection and transportation rather than treatment or drinking-
water production.
Question 2
Which agency administers occupational licensing for wastewater
collection system operators in Texas?
A. Texas Department of Transportation
B. Texas Department of State Health Services
C. U.S. Environmental Protection Agency
D. Texas Commission on Environmental Quality (TCEQ)
,Rationale: TCEQ administers Texas occupational licenses for
wastewater collection system operators. The agency establishes
licensing requirements, administers or oversees examinations,
and regulates activities associated with protection of the state's
waters.
Question 3
Which training course is specifically required for a Texas
Wastewater Collection Class I license?
A. Basic Wastewater Operation only
B. Water Utility Safety
C. Pump and Motor Maintenance
D. Wastewater Collection
Rationale: TCEQ currently lists Wastewater Collection as the
required training course for a Collection Class I license. Class I
does not require the additional elective courses required at higher
collection-system license levels.
Question 4
Which characteristic describes domestic wastewater most
accurately?
A. It consists exclusively of industrial chemicals.
B. It contains only stormwater.
C. It contains waterborne wastes generated by domestic
activities and other permitted sources.
D. It is always free of pathogenic organisms.
Rationale: Domestic wastewater commonly contains water,
human wastes, household wastewater, suspended solids,
dissolved substances, microorganisms, and other constituents.
,Its characteristics vary according to the sources contributing to
the collection system.
Question 5
What is infiltration in a wastewater collection system?
A. Wastewater leaking out through a pipe joint
B. Industrial wastewater entering a treatment plant
C. Groundwater entering the collection system through
defects or openings
D. Stormwater flowing over a manhole cover
Rationale: Infiltration is groundwater that enters a sewer system
through cracks, defective joints, porous materials, or other
openings. It can increase flows that must be conveyed and
treated.
Question 6
What is inflow?
A. Groundwater entering through defective pipe joints
B. Water entering a sanitary sewer system from sources such
as roof drains, yard drains, or improperly connected
stormwater structures
C. Wastewater leaking from a force main
D. Sludge entering a collection system
Rationale: Inflow generally refers to relatively direct connections
that allow surface or stormwater to enter the sanitary sewer.
Examples include improper connections from roof drains, area
drains, or storm drainage structures.
Question 7
Why is excessive infiltration and inflow undesirable?
, A. It eliminates all hydraulic capacity in a treatment plant
immediately.
B. It improves wastewater treatment efficiency.
C. It increases hydraulic loading and can contribute to sewer
overflows or treatment problems.
D. It prevents groundwater from entering the water cycle.
Rationale: Excessive infiltration and inflow can substantially
increase wastewater flows, especially during wet weather. The
additional hydraulic load can reduce available sewer capacity,
increase pumping requirements, and contribute to sanitary sewer
overflows or treatment-process difficulties.
Question 8
Which condition is most likely to cause a sewer blockage?
A. Properly graded pipe
B. Adequate flushing
C. Grease, debris, roots, or excessive solids accumulating in
the pipe
D. Correctly installed manhole covers
Rationale: Blockages commonly develop when grease, roots,
debris, wipes, sediment, or other materials accumulate and
restrict the pipe's cross-sectional area. Preventive inspection and
cleaning help identify and control these conditions.
Question 9
What is the primary purpose of a manhole in a gravity sewer
system?
A. To chlorinate wastewater
B. To increase wastewater temperature
C. To provide access for inspection, maintenance, and
SYSTEM OPERATOR CLASS I —
FORM C EXAM QUESTIONS WITH
CORRECT ANSWERS PLUS
RATIONALES 2026/2027 EDITION
WITH INSTANT PDF DOWNLOAD.
Question 1
What is the primary purpose of a wastewater collection system?
A. To disinfect drinking water
B. To produce potable water
C. To collect and convey wastewater to a treatment facility
D. To increase groundwater recharge
Rationale: A wastewater collection system is designed to receive
wastewater from homes, businesses, and other sources and
convey it safely to a treatment facility. Its fundamental function is
collection and transportation rather than treatment or drinking-
water production.
Question 2
Which agency administers occupational licensing for wastewater
collection system operators in Texas?
A. Texas Department of Transportation
B. Texas Department of State Health Services
C. U.S. Environmental Protection Agency
D. Texas Commission on Environmental Quality (TCEQ)
,Rationale: TCEQ administers Texas occupational licenses for
wastewater collection system operators. The agency establishes
licensing requirements, administers or oversees examinations,
and regulates activities associated with protection of the state's
waters.
Question 3
Which training course is specifically required for a Texas
Wastewater Collection Class I license?
A. Basic Wastewater Operation only
B. Water Utility Safety
C. Pump and Motor Maintenance
D. Wastewater Collection
Rationale: TCEQ currently lists Wastewater Collection as the
required training course for a Collection Class I license. Class I
does not require the additional elective courses required at higher
collection-system license levels.
Question 4
Which characteristic describes domestic wastewater most
accurately?
A. It consists exclusively of industrial chemicals.
B. It contains only stormwater.
C. It contains waterborne wastes generated by domestic
activities and other permitted sources.
D. It is always free of pathogenic organisms.
Rationale: Domestic wastewater commonly contains water,
human wastes, household wastewater, suspended solids,
dissolved substances, microorganisms, and other constituents.
,Its characteristics vary according to the sources contributing to
the collection system.
Question 5
What is infiltration in a wastewater collection system?
A. Wastewater leaking out through a pipe joint
B. Industrial wastewater entering a treatment plant
C. Groundwater entering the collection system through
defects or openings
D. Stormwater flowing over a manhole cover
Rationale: Infiltration is groundwater that enters a sewer system
through cracks, defective joints, porous materials, or other
openings. It can increase flows that must be conveyed and
treated.
Question 6
What is inflow?
A. Groundwater entering through defective pipe joints
B. Water entering a sanitary sewer system from sources such
as roof drains, yard drains, or improperly connected
stormwater structures
C. Wastewater leaking from a force main
D. Sludge entering a collection system
Rationale: Inflow generally refers to relatively direct connections
that allow surface or stormwater to enter the sanitary sewer.
Examples include improper connections from roof drains, area
drains, or storm drainage structures.
Question 7
Why is excessive infiltration and inflow undesirable?
, A. It eliminates all hydraulic capacity in a treatment plant
immediately.
B. It improves wastewater treatment efficiency.
C. It increases hydraulic loading and can contribute to sewer
overflows or treatment problems.
D. It prevents groundwater from entering the water cycle.
Rationale: Excessive infiltration and inflow can substantially
increase wastewater flows, especially during wet weather. The
additional hydraulic load can reduce available sewer capacity,
increase pumping requirements, and contribute to sanitary sewer
overflows or treatment-process difficulties.
Question 8
Which condition is most likely to cause a sewer blockage?
A. Properly graded pipe
B. Adequate flushing
C. Grease, debris, roots, or excessive solids accumulating in
the pipe
D. Correctly installed manhole covers
Rationale: Blockages commonly develop when grease, roots,
debris, wipes, sediment, or other materials accumulate and
restrict the pipe's cross-sectional area. Preventive inspection and
cleaning help identify and control these conditions.
Question 9
What is the primary purpose of a manhole in a gravity sewer
system?
A. To chlorinate wastewater
B. To increase wastewater temperature
C. To provide access for inspection, maintenance, and
