Wireline Issue 52 Winter 2021

First phase removals at the Brae Bravo field

Meanwhile, the remaining jacket (shown on page opposite, following the topsides removal) has been fitted with a navigational aid and will be left in place until summer 2022, before being lifted away in the final phase of the removals campaign. Turning the tanker Even amongst the frantic activity of this summer, Chris is keen to impress this is just a small window during a prolonged piece of work. “It’s all very well seeing the cranes lift everything, which is great and very visual, but the real work is the first seven years and the next year,” he says. “The eight weeks is complicated and where the risk is in terms of people, but it’s only eight weeks.” It is important to consider the long-term nature of this work given TAQA’s decommissioning portfolio (the largest of any operator in the basin over the coming decade). It’s for that reason that the company has taken a more strategic approach to managing its decom operations, with the decommissioning team acting as a centralised and accountable point for all decommissioning activity. Iain explains: “We’ve set up the decommissioning directorate within TAQA to ensure business focus on decommissioning activity. One of the great difficulties that operators have is moving their business from being purely an E&P company to a decommissioning company as well… You are turning around a tanker in lots of ways as it’s not the way oil and gas companies are designed. It requires clear accountability and drive throughout to efficiently execute the programme.” Given the need for decommissioning projects to draw on all aspects of the business - from finance commitments to wells work, to HSE – Iain is able to draw on these resources as internal service providers

As in many other projects, the removals process involved cutting the platform topsides away from the jacket and lifting them off, allowing the full unit to be transported to land and dismantled. Yet despite the familiarity of technique, there are still new technical feats being achieved. “Some of the lifts were very novel,” Chris explains. “Brae Bravo is very big and it’s actually two modular support frames (MSFs). The bottom layer of the platform topsides run the full length north to south, but they have eight or so modules on top. It’s like Lego, so instead of lifting all top eight modules individually, they used the wider bottom module to lift two of the upper modules as well, resulting in a combined lift. This combined set of modules was lifted by using both of Sleipnir’s cranes simultaneously.” In total, two combined lifts were completed (one for each MSF), each weighing some 8,000 tonnes. The operation also represented a monumental effort in personnel movement with up to 500 people working on the project. To put this into perspective, this was a level of manning only seen a handful of times in Thialf’s 36-year history, according to Chris. “We executed about 400,000 man-hours without any major incidents recorded in about eight to nine weeks,” Chris reflects. He credits the ongoing relationship and dialogue with contractors: “I think that’s what made it successful – that conversation, trust and ongoing relationship.” The topsides have now made their way to Vats, Norway, where they are being dismantled. TAQA is aiming for a 95% recycle target for recovered materials. The recovered steel will also be processed at a smelter close to the dismantling yard where possible, which Iain notes is an added benefit in terms of carbon and transit costs.

w ire lin e | W in te r 2 02 1 | 4 5