3:33 THE CHALLENGE
By the time you need a relief well, every day costs millions.
Once a well is blowing out, surface control may be impossible. The only remaining option is to drill a new well that physically intersects the blowing wellbore thousands of feet underground, then pump kill fluid to regain control.
The problem: after drilling, a target well's exact position is only known approximately. By 10,000 ft, conventional surveys can be off by hundreds of feet. Missing the intercept means lost time, escalating environmental damage and runaway cost.
THE GUNNAR APPROACH
Deterministic ranging, not guesswork.
Gunnar injects current that magnetizes the target's steel casing, then measures that field to compute exact distance and direction, steering the relief well to inch-level accuracy at intercept.
Our DeadAhead™ wired-pipe system ranges continuously while drilling, eliminating wireline round-trips, locating the target earlier and shortening the critical path to kill.
SCOPE OF WORK, ONE INTEGRATED TEAM
Everything a relief well demands, under one roof.
01
Relief well planning
Trajectory design, anti-collision and intercept geometry from spud to kill point.
02
Active magnetic ranging
DeadSet™ and DeadAhead™ AMR for long-range, high-confidence target location.
03
Directional drilling
Precision steering to the intercept, integrated with the ranging solution in real time.
04
Well kill & control
40+ years of well-control expertise, dynamic and bullhead kill execution.
05
Milling & re-entry
Outside-in milling to establish communication with the target wellbore.
06
Permanent abandonment
Cement placement and regulator-witnessed permanent P&A after kill.
TECHNOLOGY DEPLOYED
Proprietary tools for this application.
DeadAhead™
World-first wired-pipe AMR-while-drilling, 10× the current injection of an analogous wireline tool, continuous locate from the BHA.
DeadSet™
No-access wireline active ranging with ±1 ft accuracy, deployable on short notice and remotely.
TopGun™
AI-assisted ranging interpretation and 3D visualization for real-time intercept decisions.
PROOF, 7 PROJECTS
Where we've done it.
North Dakota, USA · 2025
Relief-Well Intercept, Kill & P&A
~8,640 ftMD, intercepted at exact planned depth
Louisiana, USA · 2025
Legacy-Well Blowout Intercept & Kill
15 daysto well control
California, USA · 2020 – ongoing
Relief-Well P&A, Legacy Gas Field
8 interceptsacross the 4-well campaign
Gulf of Mexico · 2025 – ongoing
Offshore Well Location & Intercept P&A
~28 wellsto locate, intercept & permanently P&A
Central Asia · 2025
Relief-Well Ranging & Intercept Design, Sour-Gas Blowout
Feasiblerelief well, ranging · intercept · dynamic kill
Oklahoma, USA · 2024
Shallow Close-Proximity Intercept Plan
~20 ftwell spacing, shallow intercept at ~650–700 ft
Louisiana, USA · 2020
Inland-Waters Blowout, Dynamic Kill & Relief Planning
16 ppgkill mud, perf-and-kill at ~8,170 ft; well controlled
WATCH, FROM THE FIELD
See it in motion.
3:33 
2:33 One Contractor for Relief Wells: Range, Intersect, Mill, Kill & Cement
1:21 Casing Milling Up Close: Cutting Into Steel Downhole
FREQUENTLY ASKED
Relief Wells, your questions, answered.
What is a relief well?
A relief well is a separate well drilled to intentionally intersect a blowing or uncontrolled well so it can be killed from below by pumping heavy fluid into the original wellbore. Modern relief wells use active magnetic ranging to steer to the target with inch-level accuracy.
How accurate is the intercept?
With active magnetic ranging, accuracy improves as the relief well approaches the target, reaching inch-level precision at the point of intercept, even at depths where conventional surveys are off by hundreds of feet.
How fast can Gunnar mobilize?
DeadSet™ ranging can be deployed on short notice and operated remotely. As an integrated team, Gunnar can engage on planning, ranging and well-control execution in parallel to compress the critical path.
Do you handle both emergency and planned intercepts?
Yes. Beyond emergency blowout response, the same ranging and intercept capability is used for planned operations, accessing lost or unrecorded wells for permanent abandonment and well integrity.