Bore Planning and Rig Setup

Purpose

Draw a bore path that meets the permit’s cover and every crossing clearance, inside the bend limits of the rods and the product. Then set up a work site that is anchored, protected against electrical strikes, contained for drilling fluid and briefed. Many failed bores are failed plans: an entry angle too steep, a bend too tight, or a crossing no one checked.

When to Do It

• Trigger: potholing is done and the crossing data is in hand (UG-04).
• Prerequisites: valid locate ticket, approved permit for the segment, pothole log, traffic control plan.
• Previous step: UG-04 Potholing (Daylighting).
• Next step: UG-06 Pilot Bore and Tracking.

Roles

• Foreman: owns the bore plan, the site setup and the tailboard.
• Drill operator: positions, anchors and checks the rig; sets up the strike system per the manufacturer.
• Locator operator: calibrates the locator and checks the path for interference.
• Fluid hand or helper: mixes drilling fluid and sets up containment at both pits.
• Traffic control crew: sets the work zone per the approved plan.

Equipment and Materials

• Horizontal directional drilling (HDD) rig with drill rods.
• Rig anchoring system per the manufacturer.
• Electrical strike protection: strike alarm, ground rod and equipotential mats.
• Walkover locator and a sonde matched to it.
• Drilling fluid mixing system, water source and fluid additives suited to the soil.
• Fluid containment at both pits, and a vacuum truck for recovery.
• Traffic control devices per the approved plan.

Safety

Procedure

Hold Points

Records to Keep

• Bore plan and profile, with crossing clearances noted.
• Locator calibration record.
• Strike system test.
• Tailboard sign-in sheet.
• Traffic control setup photos.

Print a blank tailboard sheet for the briefing and the crew sign-in.

Common Mistakes

• Entry angle too steep for the product. The product has to follow the same curve on pullback; check its bend limit. For a bundle, check each conduit’s limit, and ask the manufacturer when the conduits are taped or banded together.
• No room for setback. The rig needs distance to reach depth before the first crossing.
• Uncalibrated locator. Every reading after that is wrong.
• No fluid containment. Fluid in a storm drain can shut down the job and bring fines.
• Skipping the strike system test because “we tested it yesterday.”

Standards and References

• Rig and locator manufacturer instructions.
• Plastics Pipe Institute (PPI): Handbook of PE Pipe, Ch. 12 (Horizontal Directional Drilling).
• 29 CFR 1926 Subpart P: entry and exit pits.
• MUTCD Part 6: temporary traffic control.
• CGA Best Practices: directional drilling practices.
• 49 CFR Part 196: excavation near gas and hazardous liquid pipelines, including reporting any pipeline damage to the operator and calling 911 on a release.

On the Map

• HDD Rig: the directional drill, anchored, with electrical strike protection.
• Entry Pit: where the drill enters, with fluid containment.
• Directional Bore Path: the planned path drawn in this step.
• Drilling Fluid and Recovery: fluid that carries cuttings, contained and disposed of per regulations.
• Road Crossing: where the bore passes under a road; the road permit sets the depth, and traffic control protects the crew.

Related Tools

• Bore Planning Helper: sketch the entry path and setback against the first crossing, suggest a backreamer size and estimate drilling fluid. Set the number of conduits for a bundle.

The bend and pull limits come from the rod and product manufacturers. For a bundle, get the allowable pull in writing from the conduit and pulling-head manufacturers or the engineer; without it, follow UG-07 step 4.