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Turtles set timeline for wellhead removal

Turtles set timeline for wellhead removal

As featured in our last newsletter, R&D Solutions provides many niche technologies – including pyrotechnic-free casing cutting, specialist sealing and high-pressure water and garnet wellhead cutting for the removal of redundant assets when plug and abandonment has been completed.

We highlighted then that tests and trials of a new internal high-pressure water cutter had gone well and had met with the approval and sign-off from a major operator. Based on these successful trials, the equipment was mobilised to a remote island off the Northwest coast of Western Australia and for a wellhead removal operation.

Traditional methods for removing redundant wellheads have included burning equipment or diamond saws which generate heat; these options were not acceptable to the operator. In addition, it wanted excavation and digging kept to an absolute minimum so that native flora and fauna was not overly impacted.

Operations began in August 2021 with instructions to cut and pull casing sizes ranging from 6.286” to 30.00”. This represented a challenge as the wells were flooded due to the highwater tables,while all intermediate tubing and other materials were still in place. The prize for achieving this, however, was a small footprint to backfill once cutting and pulling operations were complete.

Tony Jones,the cutting tool designer who also headed up the operation, says: “Being fully self-contained in this environment is a necessity, with even the smallest items having potential to create impacts should they be overlooked or fail. The wells were particularly challenging given we used a high-pressure water cutter fully submerged and it was cutting through water to reach all the casing sizes to be removed. I was delighted with the performance of the tools. With some patience we achieved everything we set out to do and the old wellheads are gone.”

Tony and the team worked well across many disciplines and, as learnings were captured, they built on efficiencies to reduce time further and successfully finish prior to the start of flatback turtle nesting season which would have shut down operations. The island off the Northwest shelf is important for conservation, with many studies ongoing into the flatbacks which lay a clutch of around 50-60 eggs in a nest – and then only after having checked potential locations up to five times before fixing on a suitable site.

With partner Water Cut we’re proud to have been able to avoid impact on this significant natural event,allowing scientists and volunteers to continue their research and learn how human interaction can be tailored to help increase the number of hatchlings.