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New Mexico GF-9 Utility Lines Exam ACTUAL
Exam ALL 200 QUESTIONS AND CORRECT
ANSWERS LATEST UPDATE THIS YEAR
New Mexico GF-9 Utility Lines Exam – ACTUAL Questions
Full Practice Exam Overview | 2026 Update | Verified Answers & Rationales
Exam Coverage Areas (All Batches):
1. Utility line types, materials, and installation requirements (water, gas, electric, sewer).
2. Safety protocols, clearances, and excavation procedures.
3. Regulatory compliance (New Mexico One Call, state and municipal codes).
4. Installation techniques and best practices for trenches, bedding, and backfill.
5. Testing, inspection, and maintenance of utility lines.
6. Environmental and site considerations.
7. Emergency procedures and damage prevention.
Batch 1 (Questions 1–50)
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1. What is the primary purpose of a utility line in construction projects?
A) Support structural loads
B) Carry essential services such as water, gas, or electricity
C) Act as a foundation system
D) Manage surface runoff
Answer: B
Rationale: Utility lines distribute essential services and are not intended to bear structural
loads.
2. Before excavation near existing utilities, which action is required?
A) Start digging carefully
B) Inform only the property owner
C) Contact the New Mexico One Call system
D) Proceed after visually checking the site
Answer: C
Rationale: State law mandates contacting One Call to locate and mark underground utilities.
3. Minimum clearance between gas and water lines in a trench is generally:
A) 6 inches
B) 9 inches
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C) 12 inches
D) 18 inches
Answer: C
Rationale: Adequate separation prevents cross-contamination and allows maintenance.
4. Which pipe material is commonly used for potable water distribution?
A) PVC
B) Copper
C) Ductile Iron
D) All of the above
Answer: D
Rationale: Water lines may use PVC, copper, or ductile iron depending on pressure
requirements and local codes.
5. What is the recommended slope for gravity sewer lines?
A) 0.25%
B) 1%
C) 2%
D) 5%
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Answer: B
Rationale: A 1% slope ensures wastewater flows by gravity without causing sediment buildup.
6. What type of backfill material is preferred directly around utility pipes?
A) Rocky soil
B) Sand or fine gravel
C) Clay
D) Topsoil
Answer: B
Rationale: Sand or fine gravel prevents pipe damage and allows proper compaction.
7. When should utility line pressure tests be performed?
A) Before backfilling the trench
B) After backfilling only
C) One year after installation
D) Only when leaks are visible
Answer: A
Rationale: Pressure testing prior to backfill ensures the line is leak-free.
4
New Mexico GF-9 Utility Lines Exam ACTUAL
Exam ALL 200 QUESTIONS AND CORRECT
ANSWERS LATEST UPDATE THIS YEAR
New Mexico GF-9 Utility Lines Exam – ACTUAL Questions
Full Practice Exam Overview | 2026 Update | Verified Answers & Rationales
Exam Coverage Areas (All Batches):
1. Utility line types, materials, and installation requirements (water, gas, electric, sewer).
2. Safety protocols, clearances, and excavation procedures.
3. Regulatory compliance (New Mexico One Call, state and municipal codes).
4. Installation techniques and best practices for trenches, bedding, and backfill.
5. Testing, inspection, and maintenance of utility lines.
6. Environmental and site considerations.
7. Emergency procedures and damage prevention.
Batch 1 (Questions 1–50)
1
, Page 2 of 103
1. What is the primary purpose of a utility line in construction projects?
A) Support structural loads
B) Carry essential services such as water, gas, or electricity
C) Act as a foundation system
D) Manage surface runoff
Answer: B
Rationale: Utility lines distribute essential services and are not intended to bear structural
loads.
2. Before excavation near existing utilities, which action is required?
A) Start digging carefully
B) Inform only the property owner
C) Contact the New Mexico One Call system
D) Proceed after visually checking the site
Answer: C
Rationale: State law mandates contacting One Call to locate and mark underground utilities.
3. Minimum clearance between gas and water lines in a trench is generally:
A) 6 inches
B) 9 inches
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C) 12 inches
D) 18 inches
Answer: C
Rationale: Adequate separation prevents cross-contamination and allows maintenance.
4. Which pipe material is commonly used for potable water distribution?
A) PVC
B) Copper
C) Ductile Iron
D) All of the above
Answer: D
Rationale: Water lines may use PVC, copper, or ductile iron depending on pressure
requirements and local codes.
5. What is the recommended slope for gravity sewer lines?
A) 0.25%
B) 1%
C) 2%
D) 5%
3
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Answer: B
Rationale: A 1% slope ensures wastewater flows by gravity without causing sediment buildup.
6. What type of backfill material is preferred directly around utility pipes?
A) Rocky soil
B) Sand or fine gravel
C) Clay
D) Topsoil
Answer: B
Rationale: Sand or fine gravel prevents pipe damage and allows proper compaction.
7. When should utility line pressure tests be performed?
A) Before backfilling the trench
B) After backfilling only
C) One year after installation
D) Only when leaks are visible
Answer: A
Rationale: Pressure testing prior to backfill ensures the line is leak-free.
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