‘Dynamic kill’ halts leak on North Sea rig in just 12 hours

The French energy giant announced that the dynamic well kill operation – pumping heavy drilling mud down into the rogue G4 well – had succeeded in stopping the flow of gas from the ruptured well only 12 hours after the operation began.

But it could be weeks before the apparent success of the operation can be confirmed and the well finally sealed with cement.

Total admitted last night that it may take until the end of the year before full production can begin again in the oil and gas fields in the Elgin Franklin complex.

The platform, 150 miles east of Aberdeen, had to be completely abandoned on 25 March when the leak of potentially explosive gas and condensate first began.

At its height, the leaking well was spewing gas into the atmosphere at the rate of seven million cubic feet per day, costing Total up to £248 million in lost production.

The operation to stem the leak by pumping mud into the well from the drilling rig West Phoenix began at 9:20am on Tuesday. Total yesterday announced, after 1,000 tonnes of mud had been poured into the well: “The leak was stopped 12 hours later.”

The announcement was welcomed by Scottish politicians and environmental groups. But Richard Dixon, director of WWF Scotland, said: “The fact it happened at all and that a potent greenhouse gas has been spewing out for nearly two months is deeply concerning.

“This is the second serious leak in the North Sea within the past two years and underlines the risks of the offshore oil industry, even in the well-known waters around Scotland.

“We should be trying to give up our addiction to oil and gas, and not seeking it out in more difficult places with the risks to the environment that poses when things go wrong.”

Brian Adam, the SNP MSP for Aberdeen Donside, said: “Lessons must be learned from the leak and I trust that investigations will be ongoing into this matter.

“We have been lucky to avoid any serious environmental impact, and measures will hopefully be put in place to decrease the risk of any future problems at the well.”

Yves-Louis Darricarrère, Total’s president of exploration and production, said: “A major turning point has been achieved. Our absolute priority was to stop the gas leak safely and as quickly as possible.

“Since 25 March, we have been working closely with the authorities and we have communicated transparently and will continue to do so.

“We shall now fully complete the ongoing task and take into account the lessons learnt from this incident.”

However, a spokesman for Total stressed: “What we have announced is that we have stopped the leak, but the full well kill is not yet complete.

“We will monitor the behaviour in the well, and by Friday or Saturday we will hopefully be able to have reassured ourselves that the well is completely killed.

“At some point in the next few weeks we will be looking to put a cement plug in the well. But that operation is dependent upon us getting back on the Rowan Viking, the drilling rig that has been alongside the Elgin complex since the start of the incident.