CO Utility Contractor Exam Questions
and Correct Answers (Verified Answers)
Plus Rationale 2027 Q&A| Instant
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1. Which practice is most important before beginning excavation for
an underground utility installation?
A. Begin at the deepest point
B. Remove all surface markings
C. Verify the location of existing underground utilities
D. Increase excavation speed
Rationale: Existing underground utilities must be located and marked
before excavation begins. Striking a buried electrical, gas, water,
communications, or other utility can cause serious injury, service
interruption, environmental damage, and costly repairs.
2. What is the primary purpose of utility locating markings before
excavation?
, A. To identify property boundaries
B. To indicate the approximate horizontal location of
underground facilities
C. To determine soil density
D. To establish finished grades
Rationale: Utility markings help excavators identify where existing
underground facilities are believed to be located. They are a critical
part of planning safe excavation and do not necessarily indicate exact
depth.
3. When excavating near an identified underground utility, the
contractor should:
A. Use heavy equipment directly over the marked line
B. Assume the utility is deeper than the excavation
C. Use appropriate precautions and expose the utility carefully
as necessary
D. Remove the markings once excavation begins
Rationale: Markings provide information about the expected utility
location, but excavation must proceed carefully because actual
alignment and depth can vary. Controlled exposure is often necessary
when working close to existing facilities.
, 4. What is the primary function of bedding beneath a buried utility
pipe?
A. Increase pipe color visibility
B. Eliminate the need for compaction
C. Provide uniform support and help protect the pipe
D. Increase trench width
Rationale: Proper bedding supports the pipe along its intended
alignment and helps distribute loads. Suitable bedding also reduces
point loading and helps protect the pipe from damaging materials.
5. Which material is generally unsuitable for placing directly against
many utility pipes?
A. Approved granular bedding
B. Properly graded sand
C. Specified fine backfill
D. Large rocks or sharp debris
Rationale: Large rocks and sharp debris can create concentrated loads
or damage pipe surfaces. Utility specifications commonly require
suitable bedding and initial backfill materials around the pipe.
6. Why is trench compaction important during utility installation?
A. It eliminates the need for utility markers
B. It reduces settlement and provides required support
, C. It increases pipe diameter
D. It prevents all groundwater infiltration
Rationale: Proper compaction reduces voids in the backfill and helps
prevent future settlement. It also provides structural support for the
utility and the surface above it.
7. A trench is being excavated in unstable soil. What should the
contractor do?
A. Allow workers to enter without protection
B. Increase the trench depth
C. Provide an appropriate protective system or otherwise
comply with excavation safety requirements
D. Place workers at the bottom while equipment operates
overhead
Rationale: Unstable soil can collapse suddenly. Protective systems
such as sloping, benching, or approved trench protective systems are
used according to applicable requirements and site conditions.
8. What is the purpose of trench shoring?
A. Increase water pressure
B. Improve pipe flow
C. Protect workers from trench-wall collapse
D. Replace pipe bedding
and Correct Answers (Verified Answers)
Plus Rationale 2027 Q&A| Instant
Download Pdf
1. Which practice is most important before beginning excavation for
an underground utility installation?
A. Begin at the deepest point
B. Remove all surface markings
C. Verify the location of existing underground utilities
D. Increase excavation speed
Rationale: Existing underground utilities must be located and marked
before excavation begins. Striking a buried electrical, gas, water,
communications, or other utility can cause serious injury, service
interruption, environmental damage, and costly repairs.
2. What is the primary purpose of utility locating markings before
excavation?
, A. To identify property boundaries
B. To indicate the approximate horizontal location of
underground facilities
C. To determine soil density
D. To establish finished grades
Rationale: Utility markings help excavators identify where existing
underground facilities are believed to be located. They are a critical
part of planning safe excavation and do not necessarily indicate exact
depth.
3. When excavating near an identified underground utility, the
contractor should:
A. Use heavy equipment directly over the marked line
B. Assume the utility is deeper than the excavation
C. Use appropriate precautions and expose the utility carefully
as necessary
D. Remove the markings once excavation begins
Rationale: Markings provide information about the expected utility
location, but excavation must proceed carefully because actual
alignment and depth can vary. Controlled exposure is often necessary
when working close to existing facilities.
, 4. What is the primary function of bedding beneath a buried utility
pipe?
A. Increase pipe color visibility
B. Eliminate the need for compaction
C. Provide uniform support and help protect the pipe
D. Increase trench width
Rationale: Proper bedding supports the pipe along its intended
alignment and helps distribute loads. Suitable bedding also reduces
point loading and helps protect the pipe from damaging materials.
5. Which material is generally unsuitable for placing directly against
many utility pipes?
A. Approved granular bedding
B. Properly graded sand
C. Specified fine backfill
D. Large rocks or sharp debris
Rationale: Large rocks and sharp debris can create concentrated loads
or damage pipe surfaces. Utility specifications commonly require
suitable bedding and initial backfill materials around the pipe.
6. Why is trench compaction important during utility installation?
A. It eliminates the need for utility markers
B. It reduces settlement and provides required support
, C. It increases pipe diameter
D. It prevents all groundwater infiltration
Rationale: Proper compaction reduces voids in the backfill and helps
prevent future settlement. It also provides structural support for the
utility and the surface above it.
7. A trench is being excavated in unstable soil. What should the
contractor do?
A. Allow workers to enter without protection
B. Increase the trench depth
C. Provide an appropriate protective system or otherwise
comply with excavation safety requirements
D. Place workers at the bottom while equipment operates
overhead
Rationale: Unstable soil can collapse suddenly. Protective systems
such as sloping, benching, or approved trench protective systems are
used according to applicable requirements and site conditions.
8. What is the purpose of trench shoring?
A. Increase water pressure
B. Improve pipe flow
C. Protect workers from trench-wall collapse
D. Replace pipe bedding
