NORTH CAROLINA (NC) PUBLIC UTILITIES CONTRACTOR PRACTICE TEST EXAM QUESTIONS AND CORRECT
ANSWERS (VERIFIED ANSWERS) PLUS RATIONALES 2026 Q&A |LATEST EXAM UPDATE 2026/2027.
Core Domains
Water Distribution Systems: Design, Installation, Maintenance, and Repair
Sanitary and Storm Sewer Collection Systems
Backflow Prevention and Cross-Connection Control
Trenching, Excavation, and Construction Safety (OSHA)
Pipeline Materials, Jointing, and Installation Techniques
Testing, Inspection, and Disinfection Procedures
Environmental Compliance and Erosion Control
North Carolina Licensing, Regulations, and Business Law
Introduction
This comprehensive practice examination is meticulously designed to prepare candidates for the North Carolina
Public Utilities (PU) Contractor Licensing Exam. It assesses the essential skills and knowledge required for the
competent and lawful construction, installation, and repair of water, sewer, and other utility pipeline systems. The
exam is structured with multiple-choice questions that integrate foundational theory with applied professional
knowledge, regulatory compliance, and critical thinking. Emphasis is placed on real-world application and sound
decision-making to ensure public safety and adherence to North Carolina standards and statutes. This resource is
intended to build confidence and identify areas for further study.
,SECTION ONE: QUESTIONS 1–100
Question 1
Which agency is responsible for issuing the Public Utilities (PU) contractor license in North Carolina?
A. NC Department of Environmental Quality (NCDEQ)
B. NC Department of Transportation (NCDOT)
C. North Carolina Licensing Board for General Contractors (NCLBGC)
D. NC Utilities Commission
🟢 C. North Carolina Licensing Board for General Contractors (NCLBGC)
🔴 RATIONALE: The North Carolina Licensing Board for General Contractors (NCLBGC) is the sole state agency
that issues and regulates all general contractor licenses, including the Public Utilities classification . Other
agencies may set regulations but do not issue the license.
Question 2
According to OSHA regulations, what is the minimum depth of a trench that generally requires a protective
system such as shoring or sloping?
A. 4 feet
B. 5 feet
C. 6 feet
D. 8 feet
🟢 B. 5 feet
,🔴 RATIONALE: OSHA standard 1926 Subpart P requires that trenches 5 feet deep or greater be provided with a
protective system unless the excavation is made entirely in stable rock . This is a critical safety regulation to
prevent cave-ins.
Question 3
What is the primary purpose of a "blow-off" assembly installed at the end of a water main?
A. To connect to a fire hydrant
B. To release excess pressure from the system
C. To flush sediment and trapped air from the main
D. To provide a connection for a future main extension
🟢 C. To flush sediment and trapped air from the main
🔴 RATIONALE: Blow-offs are used to remove accumulated sediment, debris, and trapped air, which helps
maintain water quality and ensures proper system flow .
Question 4
Which of the following pipe materials is generally most resistant to corrosion when used in a sanitary sewer
system?
A. Ductile iron
B. PVC
, C. Concrete
D. Steel
🟢 B. PVC
🔴 RATIONALE: PVC (polyvinyl chloride) is chemically inert and highly resistant to the corrosive gases and acids
commonly found in sewer systems, making it a preferred material for this application .
Question 5
What is the general minimum depth for burying a water main in North Carolina to protect against freezing?
A. 18 inches
B. 24 inches
C. 36 inches
D. 48 inches
🟢 C. 36 inches
🔴 RATIONALE: Water mains in North Carolina are typically installed below the frost line to prevent freezing,
which is generally around 36 inches . Local codes may vary, but 36 inches is the standard.
Question 6
A contractor is installing a new sewer line and discovers a discrepancy between the design plans and existing
site conditions. What is the appropriate course of action?
ANSWERS (VERIFIED ANSWERS) PLUS RATIONALES 2026 Q&A |LATEST EXAM UPDATE 2026/2027.
Core Domains
Water Distribution Systems: Design, Installation, Maintenance, and Repair
Sanitary and Storm Sewer Collection Systems
Backflow Prevention and Cross-Connection Control
Trenching, Excavation, and Construction Safety (OSHA)
Pipeline Materials, Jointing, and Installation Techniques
Testing, Inspection, and Disinfection Procedures
Environmental Compliance and Erosion Control
North Carolina Licensing, Regulations, and Business Law
Introduction
This comprehensive practice examination is meticulously designed to prepare candidates for the North Carolina
Public Utilities (PU) Contractor Licensing Exam. It assesses the essential skills and knowledge required for the
competent and lawful construction, installation, and repair of water, sewer, and other utility pipeline systems. The
exam is structured with multiple-choice questions that integrate foundational theory with applied professional
knowledge, regulatory compliance, and critical thinking. Emphasis is placed on real-world application and sound
decision-making to ensure public safety and adherence to North Carolina standards and statutes. This resource is
intended to build confidence and identify areas for further study.
,SECTION ONE: QUESTIONS 1–100
Question 1
Which agency is responsible for issuing the Public Utilities (PU) contractor license in North Carolina?
A. NC Department of Environmental Quality (NCDEQ)
B. NC Department of Transportation (NCDOT)
C. North Carolina Licensing Board for General Contractors (NCLBGC)
D. NC Utilities Commission
🟢 C. North Carolina Licensing Board for General Contractors (NCLBGC)
🔴 RATIONALE: The North Carolina Licensing Board for General Contractors (NCLBGC) is the sole state agency
that issues and regulates all general contractor licenses, including the Public Utilities classification . Other
agencies may set regulations but do not issue the license.
Question 2
According to OSHA regulations, what is the minimum depth of a trench that generally requires a protective
system such as shoring or sloping?
A. 4 feet
B. 5 feet
C. 6 feet
D. 8 feet
🟢 B. 5 feet
,🔴 RATIONALE: OSHA standard 1926 Subpart P requires that trenches 5 feet deep or greater be provided with a
protective system unless the excavation is made entirely in stable rock . This is a critical safety regulation to
prevent cave-ins.
Question 3
What is the primary purpose of a "blow-off" assembly installed at the end of a water main?
A. To connect to a fire hydrant
B. To release excess pressure from the system
C. To flush sediment and trapped air from the main
D. To provide a connection for a future main extension
🟢 C. To flush sediment and trapped air from the main
🔴 RATIONALE: Blow-offs are used to remove accumulated sediment, debris, and trapped air, which helps
maintain water quality and ensures proper system flow .
Question 4
Which of the following pipe materials is generally most resistant to corrosion when used in a sanitary sewer
system?
A. Ductile iron
B. PVC
, C. Concrete
D. Steel
🟢 B. PVC
🔴 RATIONALE: PVC (polyvinyl chloride) is chemically inert and highly resistant to the corrosive gases and acids
commonly found in sewer systems, making it a preferred material for this application .
Question 5
What is the general minimum depth for burying a water main in North Carolina to protect against freezing?
A. 18 inches
B. 24 inches
C. 36 inches
D. 48 inches
🟢 C. 36 inches
🔴 RATIONALE: Water mains in North Carolina are typically installed below the frost line to prevent freezing,
which is generally around 36 inches . Local codes may vary, but 36 inches is the standard.
Question 6
A contractor is installing a new sewer line and discovers a discrepancy between the design plans and existing
site conditions. What is the appropriate course of action?
