Page 1 of 116
New Mexico GF-9 Utility Lines Exam Comprehensive
EXAM ACTUAL EXAM COMPLETE 200 QUESTIONS AND
VERIFIED SOLUTIONS LATEST UPDATE THIS YEAR
New Mexico GF-9 Utility Lines Exam: Comprehensive Overview
The New Mexico GF-9 Utility Lines exam is a technical trade certification administered by PSI
Services for the New Mexico Construction Industries Division (CID). It specifically authorizes the
construction, installation, and repair of utility systems for sewage, natural gas, and water, as
well as underground communication cables.
Exam Coverage & Batch Structure
To provide full coverage of the "GF-9" scope and the required "GF Core" knowledge, these
questions are organized into batches reflecting the official content areas:
Batch 1: Core Knowledge & Earthwork
Excavation, grading, soil compaction, and OSHA trench safety/shoring.
Batch 2: Pipe Installation & Miscellaneous Structures
Potable water distribution, gravity sewers, gas lines, manholes, catch basins, and vaults.
Batch 3: Surface Repair, Restoration & Project Management
Asphalt/concrete paving, traffic control, erosion control, cost estimation, and CPM scheduling.
New Mexico GF-9 Utility Lines Exam
Utility Line Installation Fundamentals – Methods for installing underground utility lines
including trenching, boring, and directional drilling.
Types of Utility Systems – Water, sewer, gas, electric, telecommunications, and fiber-optic line
installation requirements.
Excavation & Trenching Safety – OSHA safety standards, trench protection systems, soil
classification, and worker safety procedures.
Utility Location & Damage Prevention – One-Call systems (811), locating existing utilities,
marking codes, and prevention of line strikes.
,Page 2 of 116
Backfilling & Compaction – Proper materials, compaction methods, and restoration of
disturbed surfaces.
Pipe & Conduit Materials – PVC, HDPE, ductile iron, copper, steel, and conduit used for
electrical and communication lines.
Joining & Connection Methods – Mechanical joints, solvent welding, fusion welding, couplings,
and fittings.
Depth & Clearance Requirements – Minimum burial depths and separation distances between
utilities.
Testing & Inspection – Pressure testing, leakage testing, inspection procedures, and compliance
with specifications.
Blueprints & Utility Plans – Reading construction drawings, profiles, and site plans for utility
line placement.
Codes & Regulations – New Mexico construction regulations, local utility standards, and
environmental compliance.
Site Restoration – Surface repair, erosion control, and environmental protection after
installation.
Batch 1: Core Knowledge & Earthwork (Questions 1-50)
A contractor is preparing to excavate a trench for a new natural gas line in an area with
known existing underground utilities. According to New Mexico state regulations and the
"One Call" system, what is the mandatory first step before any mechanized equipment
touches the ground?
A) Perform a visual site survey and begin hand-digging to verify depths.
B) Contact the New Mexico One Call (811) system at least two working days prior to excavation.
,Page 3 of 116
C) Notify only the local gas utility company of the intent to dig.
D) Consult the original city blueprints and proceed if no conflicts are found.
Correct Answer: ✅ B
Rationale: State law requires notification through the One Call system to have underground
lines marked. Relying on blueprints (D) is insufficient as they may be outdated.
During an excavation in Type B soil, a competent person determines that shoring is required
for a trench 6 feet deep. What is the OSHA-mandated maximum distance that the shoring or
trench box must extend above the top of the vertical side to prevent materials from rolling
into the trench?
A) 6 inches.
B) 12 inches.
C) 18 inches.
D) 24 inches.
Correct Answer: ✅ C
, Page 4 of 116
Rationale: OSHA standards for trench safety (often covered in GF-9 prep) require shoring to
extend at least 18 inches above the vertical wall to provide a protective lip.
When compacting backfill for a utility line under a proposed roadway, which soil classification
typically requires "kneading" action (such as a sheepsfoot roller) to achieve the required 95%
Proctor density?
A) Clean, well-graded sand.
B) Cohesive clay soils.
C) Non-cohesive gravel.
D) Crushed rock base.
Correct Answer: ✅ B
Rationale: Cohesive soils (clays) require the high pressure and kneading action of a sheepsfoot
roller to break down soil clumps and remove air voids, unlike granular soils which respond
better to vibration.
A GF-9 contractor is installing a sewage lift station. Which of the following activities is
EXPLICITLY excluded from the GF-9 license scope according to N.M. Admin. Code § 14.6.6.9?
New Mexico GF-9 Utility Lines Exam Comprehensive
EXAM ACTUAL EXAM COMPLETE 200 QUESTIONS AND
VERIFIED SOLUTIONS LATEST UPDATE THIS YEAR
New Mexico GF-9 Utility Lines Exam: Comprehensive Overview
The New Mexico GF-9 Utility Lines exam is a technical trade certification administered by PSI
Services for the New Mexico Construction Industries Division (CID). It specifically authorizes the
construction, installation, and repair of utility systems for sewage, natural gas, and water, as
well as underground communication cables.
Exam Coverage & Batch Structure
To provide full coverage of the "GF-9" scope and the required "GF Core" knowledge, these
questions are organized into batches reflecting the official content areas:
Batch 1: Core Knowledge & Earthwork
Excavation, grading, soil compaction, and OSHA trench safety/shoring.
Batch 2: Pipe Installation & Miscellaneous Structures
Potable water distribution, gravity sewers, gas lines, manholes, catch basins, and vaults.
Batch 3: Surface Repair, Restoration & Project Management
Asphalt/concrete paving, traffic control, erosion control, cost estimation, and CPM scheduling.
New Mexico GF-9 Utility Lines Exam
Utility Line Installation Fundamentals – Methods for installing underground utility lines
including trenching, boring, and directional drilling.
Types of Utility Systems – Water, sewer, gas, electric, telecommunications, and fiber-optic line
installation requirements.
Excavation & Trenching Safety – OSHA safety standards, trench protection systems, soil
classification, and worker safety procedures.
Utility Location & Damage Prevention – One-Call systems (811), locating existing utilities,
marking codes, and prevention of line strikes.
,Page 2 of 116
Backfilling & Compaction – Proper materials, compaction methods, and restoration of
disturbed surfaces.
Pipe & Conduit Materials – PVC, HDPE, ductile iron, copper, steel, and conduit used for
electrical and communication lines.
Joining & Connection Methods – Mechanical joints, solvent welding, fusion welding, couplings,
and fittings.
Depth & Clearance Requirements – Minimum burial depths and separation distances between
utilities.
Testing & Inspection – Pressure testing, leakage testing, inspection procedures, and compliance
with specifications.
Blueprints & Utility Plans – Reading construction drawings, profiles, and site plans for utility
line placement.
Codes & Regulations – New Mexico construction regulations, local utility standards, and
environmental compliance.
Site Restoration – Surface repair, erosion control, and environmental protection after
installation.
Batch 1: Core Knowledge & Earthwork (Questions 1-50)
A contractor is preparing to excavate a trench for a new natural gas line in an area with
known existing underground utilities. According to New Mexico state regulations and the
"One Call" system, what is the mandatory first step before any mechanized equipment
touches the ground?
A) Perform a visual site survey and begin hand-digging to verify depths.
B) Contact the New Mexico One Call (811) system at least two working days prior to excavation.
,Page 3 of 116
C) Notify only the local gas utility company of the intent to dig.
D) Consult the original city blueprints and proceed if no conflicts are found.
Correct Answer: ✅ B
Rationale: State law requires notification through the One Call system to have underground
lines marked. Relying on blueprints (D) is insufficient as they may be outdated.
During an excavation in Type B soil, a competent person determines that shoring is required
for a trench 6 feet deep. What is the OSHA-mandated maximum distance that the shoring or
trench box must extend above the top of the vertical side to prevent materials from rolling
into the trench?
A) 6 inches.
B) 12 inches.
C) 18 inches.
D) 24 inches.
Correct Answer: ✅ C
, Page 4 of 116
Rationale: OSHA standards for trench safety (often covered in GF-9 prep) require shoring to
extend at least 18 inches above the vertical wall to provide a protective lip.
When compacting backfill for a utility line under a proposed roadway, which soil classification
typically requires "kneading" action (such as a sheepsfoot roller) to achieve the required 95%
Proctor density?
A) Clean, well-graded sand.
B) Cohesive clay soils.
C) Non-cohesive gravel.
D) Crushed rock base.
Correct Answer: ✅ B
Rationale: Cohesive soils (clays) require the high pressure and kneading action of a sheepsfoot
roller to break down soil clumps and remove air voids, unlike granular soils which respond
better to vibration.
A GF-9 contractor is installing a sewage lift station. Which of the following activities is
EXPLICITLY excluded from the GF-9 license scope according to N.M. Admin. Code § 14.6.6.9?
