LA-7-136 Horizontal Directional Drilling
LA-7-136 HORIZONTAL DIRECTIONAL DRILLING |
REAL EXAM 2026/2027 | QUESTIONS AND VERIFIED
ANSWERS | NEWEST VERSION
.
1. What is the primary purpose of horizontal directional drilling
(HDD)?
A. To drill vertical water wells
B. To compact soil for foundations
C. To install underground utilities with minimal surface disruption
ANSWER
D. To excavate open trenches faster
2. Which stage of an HDD installation is performed first?
A. Site restoration
B. Pullback
C. Reaming
D. Pilot bore ANSWER
3. What is the second stage of a typical HDD installation?
A. Mud recycling
B. Pullback
C. Pilot bore
D. Reaming (backreaming) ANSWER
4. What is the final stage of an HDD installation?
A. Pilot bore
B. Reaming
C. Pullback of the product pipe ANSWER
D. Potholing
5. What is the main function of drilling fluid in HDD?
A. To mark the bore path on the surface
B. To harden the soil around the bore
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, LA-7-136 Horizontal Directional Drilling
C. To power the drill rig engine
D. To lubricate, cool the cutting tool, and remove spoil from the bore
ANSWER
6. Bentonite is commonly used in HDD drilling fluid primarily because
it
A. Forms a stable filter cake and carries cuttings ANSWER
B. Increases the electrical conductivity of the soil
C. Is inexpensive compared to water
D. Reduces the need for a locating system
7. What does the term 'annular space' refer to in HDD?
A. The pit where drilling fluid is mixed
B. The zone where entry and exit angles meet
C. The area where the rig is set up
D. The space between the drill pipe or product and the borehole wall
ANSWER
8. What is 'frac-out' in HDD terminology?
A. A break in the product pipe during pullback
B. An uncontrolled release of drilling fluid to the surface or a water body
ANSWER
C. A mechanical failure of the drill rig
D. The point where the bore reaches design depth
9. Which instrument is primarily used to track the position of the drill
head during the pilot bore?
A. Walkover locator (tracking system) ANSWER
B. Laser level
C. Flow meter
D. Pressure gauge
10. What is the purpose of a 'sonde' in HDD tracking?
A. A transmitter housed near the drill head that emits a signal for locating
ANSWER
B. A hydraulic pump on the rig
C. A type of drilling fluid additive
D. A cutting tool attached to the reamer
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, LA-7-136 Horizontal Directional Drilling
11. What does entry angle refer to in an HDD bore profile?
A. The slope of the exit pit
B. The angle at which the drill string enters the ground at the entry point
ANSWER
C. The angle of the reamer relative to the pipe
D. The angle of the rig anchors
12. A typical HDD entry angle ranges between which values?
A. 45 to 60 degrees
B. 70 to 90 degrees
C. 0 to 2 degrees
D. 8 to 20 degrees ANSWER
13. What is the minimum recommended depth of cover for a typical
utility HDD crossing, absent other governing requirements?
A. There is no minimum depth requirement
B. Always exactly 100 feet
C. Exactly 6 inches
D. Sufficient to maintain safe clearance based on engineering design and
utility standards ANSWER
14. Before beginning any excavation or drilling, what must be
completed to identify existing utilities?
A. A pullback force calculation only
B. A utility locate request (e.g., call-before-you-dig / one-call notification)
ANSWER
C. A soil compaction test only
D. A weather forecast review only
15. What is 'potholing' (or daylighting) used for in HDD projects?
A. Mixing drilling fluid at the surface
B. Physically exposing an existing utility to confirm its location and depth
ANSWER
C. Testing the tensile strength of the product pipe
D. Creating the entry pit for the rig
16. Which document typically shows the planned bore path, depth, and
profile for an HDD crossing?
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, LA-7-136 Horizontal Directional Drilling
A. The material safety data sheet
B. The daily tailgate log only
C. The bore plan/profile drawing ANSWER
D. The rig operator's certification card
17. What is the primary safety hazard associated with locating buried
utilities incorrectly during HDD?
A. Increased reamer wear
B. Utility strikes, which can cause injury, service outages, or explosions
ANSWER
C. Excess drilling fluid viscosity
D. Reduced pullback speed
18. What does 'as-built' documentation record after an HDD
installation?
A. The crew's daily attendance record
B. The manufacturer's warranty terms
C. The actual installed location, depth, and path of the pipe as constructed
ANSWER
D. The projected cost of the project
19. Which of the following is a common cause of inadvertent returns
(frac-out) during HDD?
A. Excessive drilling fluid pressure relative to soil confinement ANSWER
B. Operating the rig at too low an engine RPM
C. Using too little drilling fluid additive
D. Using an oversized product pipe
20. What immediate action should be taken if a frac-out occurs near a
waterway?
A. Ignore it if it appears minor
B. Increase mud pump pressure to push through
C. Continue drilling to complete the bore quickly
D. Stop pumping fluid, contain the release, and notify appropriate
personnel/regulators as required ANSWER
21. What is the purpose of a mud recycling (reclaiming) system on an
HDD site?
Page 4 of 41
LA-7-136 HORIZONTAL DIRECTIONAL DRILLING |
REAL EXAM 2026/2027 | QUESTIONS AND VERIFIED
ANSWERS | NEWEST VERSION
.
1. What is the primary purpose of horizontal directional drilling
(HDD)?
A. To drill vertical water wells
B. To compact soil for foundations
C. To install underground utilities with minimal surface disruption
ANSWER
D. To excavate open trenches faster
2. Which stage of an HDD installation is performed first?
A. Site restoration
B. Pullback
C. Reaming
D. Pilot bore ANSWER
3. What is the second stage of a typical HDD installation?
A. Mud recycling
B. Pullback
C. Pilot bore
D. Reaming (backreaming) ANSWER
4. What is the final stage of an HDD installation?
A. Pilot bore
B. Reaming
C. Pullback of the product pipe ANSWER
D. Potholing
5. What is the main function of drilling fluid in HDD?
A. To mark the bore path on the surface
B. To harden the soil around the bore
Page 1 of 41
, LA-7-136 Horizontal Directional Drilling
C. To power the drill rig engine
D. To lubricate, cool the cutting tool, and remove spoil from the bore
ANSWER
6. Bentonite is commonly used in HDD drilling fluid primarily because
it
A. Forms a stable filter cake and carries cuttings ANSWER
B. Increases the electrical conductivity of the soil
C. Is inexpensive compared to water
D. Reduces the need for a locating system
7. What does the term 'annular space' refer to in HDD?
A. The pit where drilling fluid is mixed
B. The zone where entry and exit angles meet
C. The area where the rig is set up
D. The space between the drill pipe or product and the borehole wall
ANSWER
8. What is 'frac-out' in HDD terminology?
A. A break in the product pipe during pullback
B. An uncontrolled release of drilling fluid to the surface or a water body
ANSWER
C. A mechanical failure of the drill rig
D. The point where the bore reaches design depth
9. Which instrument is primarily used to track the position of the drill
head during the pilot bore?
A. Walkover locator (tracking system) ANSWER
B. Laser level
C. Flow meter
D. Pressure gauge
10. What is the purpose of a 'sonde' in HDD tracking?
A. A transmitter housed near the drill head that emits a signal for locating
ANSWER
B. A hydraulic pump on the rig
C. A type of drilling fluid additive
D. A cutting tool attached to the reamer
Page 2 of 41
, LA-7-136 Horizontal Directional Drilling
11. What does entry angle refer to in an HDD bore profile?
A. The slope of the exit pit
B. The angle at which the drill string enters the ground at the entry point
ANSWER
C. The angle of the reamer relative to the pipe
D. The angle of the rig anchors
12. A typical HDD entry angle ranges between which values?
A. 45 to 60 degrees
B. 70 to 90 degrees
C. 0 to 2 degrees
D. 8 to 20 degrees ANSWER
13. What is the minimum recommended depth of cover for a typical
utility HDD crossing, absent other governing requirements?
A. There is no minimum depth requirement
B. Always exactly 100 feet
C. Exactly 6 inches
D. Sufficient to maintain safe clearance based on engineering design and
utility standards ANSWER
14. Before beginning any excavation or drilling, what must be
completed to identify existing utilities?
A. A pullback force calculation only
B. A utility locate request (e.g., call-before-you-dig / one-call notification)
ANSWER
C. A soil compaction test only
D. A weather forecast review only
15. What is 'potholing' (or daylighting) used for in HDD projects?
A. Mixing drilling fluid at the surface
B. Physically exposing an existing utility to confirm its location and depth
ANSWER
C. Testing the tensile strength of the product pipe
D. Creating the entry pit for the rig
16. Which document typically shows the planned bore path, depth, and
profile for an HDD crossing?
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, LA-7-136 Horizontal Directional Drilling
A. The material safety data sheet
B. The daily tailgate log only
C. The bore plan/profile drawing ANSWER
D. The rig operator's certification card
17. What is the primary safety hazard associated with locating buried
utilities incorrectly during HDD?
A. Increased reamer wear
B. Utility strikes, which can cause injury, service outages, or explosions
ANSWER
C. Excess drilling fluid viscosity
D. Reduced pullback speed
18. What does 'as-built' documentation record after an HDD
installation?
A. The crew's daily attendance record
B. The manufacturer's warranty terms
C. The actual installed location, depth, and path of the pipe as constructed
ANSWER
D. The projected cost of the project
19. Which of the following is a common cause of inadvertent returns
(frac-out) during HDD?
A. Excessive drilling fluid pressure relative to soil confinement ANSWER
B. Operating the rig at too low an engine RPM
C. Using too little drilling fluid additive
D. Using an oversized product pipe
20. What immediate action should be taken if a frac-out occurs near a
waterway?
A. Ignore it if it appears minor
B. Increase mud pump pressure to push through
C. Continue drilling to complete the bore quickly
D. Stop pumping fluid, contain the release, and notify appropriate
personnel/regulators as required ANSWER
21. What is the purpose of a mud recycling (reclaiming) system on an
HDD site?
Page 4 of 41
