Worker William Cardno describes Elgin evacuation

One of the last people to leave an offshore platform which started leaking gas in the middle of the North Sea has described the evacuation.

William Cardno was one of 19 men who stayed on board the stricken Elgin platform when a leak was discovered on 25 March.

Owners Total hopes to fly a team of experts to the platform on Thursday to assess the leak.

The mission was cancelled on Wednesday due to bad weather.

About 200,000 cubic metres of gas are escaping from the platform each day, coming out from a rock formation below the sea.

It is then escaping into the air from a leak on the platform at the top of the well, about 80ft above sea level.

While most of the 238 workers on the platform were evacuated immediately, some stayed behind to monitor the situation and facilitate potentially vital information about the leak being found.

Mr Cardno, the offshore installation manager, was speaking in an interview posted on Total's website.

He said: "Even though we train for this, and we train regularly with drills every week, I never thought this would happen.

"When the first alarm was sounded we had the helicopter on-scene within one hour. And within an hour after that we had 107 people evacuated. An hour after that we had the full 220 people evacuated.

"We deliberately kept 19 people on board the platform to evaluate the situation and to see if there was anything we could do and really to maintain the systems. We knew once we turned the key to switch everything off all that was lost. That information was invaluable in trying to determine what the cause of the incident was."

He said the hardest decision was when the 19 people still on board had to make a call on whether to leave or stay.

"If we had any escalation at all on the platform we were absolutely confident we could have been off the platform in five minutes by lifeboat," he added.

"We all practised our lifeboat drill and we checked the lifeboat and strapped ourselves into it. The weather was good, the sea state was calm. It wasn't an unacceptable risk to go by boat.

"I think this demonstrated that our procedures are good and our process is good. Although we never want these things to happen, when it does happen this clearly demonstrates that the safety of the people is our paramount priority."

Relief well

The company has previously said it is "actively preparing" operations to regain control of the well, which is about 150 miles off the coast of Aberdeen.

One option for dealing with the problem is pumping mud into the well, which would need people to re-board the platform.

Total has completed talks with the Health and Safety Executive about how this can be done safely and that it hopes outside specialists could board the platform, accompanied by Total personnel, when the weather permits.

Another option is to drill a relief well and a back-up relief well but this could take months.

Total, which has its headquarters in France, has already mobilised two rigs to drill the relief wells and said both will move to the site when they finish their current operations.