AMC’s Borehole Optimisation Solution™ (AMC BOS™) secured casing, improved fluid returns and advanced an abandoned borehole in Arizona, USA. The solution provided significant financial benefit, addressing issues which the drilling contractor had been facing for over 10 years with conventional grouting methods.
Challenge
At a large mining site in Arizona, the drilling contractor had spent two weeks trying to advance a drill hole with traditional grouting methods but due to sloughing and caving around the drilled casing the crew were unable to advance. The team had battled these issues throughout a 10 year period at the site.
The lack of adequate cement seal around the casing was causing ongoing ground control issues as they tried advancing directly from a cut out of the window wedge down at 2,732ft. The hole was also facing formation pressure due to the fluids on the outside of the drill casing annular space along with only 50% fluid returns, with 50% leaking off behind the casing.
As a result of the poor conditions and outcomes of the previous fluid program, the crew had decided to abandon the borehole.
Results
- Produced considerable financial returns by recovering and completing a borehole that a mining company had decided to abandon
- Effectively sealed casing, reducing fluid leakage
- Significantly reduced torque
- Saved time, was faster, easier and more efficient compared to traditional grouting
- Reduced rod trips
- Improved bit life
- Improved hole stability by consolidating the formation
- Improved overall productivity and site safety.