THE ELGIN GAS LEAK

It is amazing how events come and go in the media. I have only now, on the 15th April, got round to writing about the gas leak which took place on 25th March at the Elgin WHP platform, which is attached to the main platform by a bridge. The Rowan Viking was alongside with its drilling package cantilevered out, doing something, either drilling new wells or working over existing ones. The Elgin platform had been producing 250,000 ballels per day of oil and oil equivalent, and this contributed about 7% of the gas requirements of the UK.

Possibly in an event unrelated to the activities of the Rowan Viking, gas started leaking at the surface, apparently from a formation above the level at which the plug had been set in a well which had been abandoned. This was revealed by Total after some investigation.

In the way these things always play out, as soon as the news was in the public domain ,a bunch of TV men arrived on Greyhope Road in Aberdeen and set up their equipment so that the TV presenters could be seen on screen with the Aberdeen Harbour in the background. They remained there for a few days, doing their one minute pieces to camera for the 24 hours news programmes, while the directors hoped that there would be ships passing behind them. Aberdeen Harbour is of course a long way from the Elgin Platform.

Overnight on 25th Total had left 19 people out there, one assumes on the platform rather than on the rig, but they were evacuated the following morning. On should remember at this time that the gas was escaping from the wellhead platform and nearly everyone had been evacuated – some into a Norwegian rescue helicopter, which was the first to arrive on the scene after the Mayday had been broadcast. So one of the nineteen must have checked out the helideck for gas. After all, the last thing one would want would have been a helicopter igniting the gas at the moment of landing.

Indeed the last time all hands were evacuated due to a gas leak, leaving the installation intact, was at the Hewett A in 1967. This small platform suffered a gas blowout during the drilling and completion operations. Most of the crew evacuated to the support vessel Hector Gannet, which was holed due to collision with the platform and sank. So they had to be rescued again by the trawler Boston Hornet. Sadly some of the crew of the Hector Gannet were lost.

As an interesting side-issue which would have been considered to have been over the top cliff-hanger in fiction, the flare was still burning after the evacuation of everyone from the Elgin. There have been discussions as to whether this had to be left burning to blow down the inventory on the rig, or whether it could have been extinguished and the blowdown could still have taken place. Of course, all it would have taken was for the LEL, the Lower Explosion Limit, to have been exceeded at the flare and boom, or should that be BOOM! However, on 31st March the flare went out, and with it interest in the emergency was also extinguished.

The Aberdeen Press and Journal headlined the possibility that there had been concerns about pressure in the annulus up the four weeks before the leak made itself felt, and doubtless there will be more of this as the investigation into the event is carried out. But maybe most importantly everyone was safely evacuated, and Greenpeace have struggled to identify pollution. The reality is that the gas will disperse and the light crude will evaporate.

As the event reached what one might call maturity a team returned to the rig, and there are mutterings about pumping heavy mud down the hole to sort out the problem. One should remember now that there are all the facilities for carrying out this task on one of the newest jack-ups in the world, already on location, the Rowan Viking. If it is possible to do the job then the Rowan Viking can do it.

Meanwhile Total is taking other steps. The Rowan Gorilla V is at a location about three miles to the south, development drilling for the Company, and there is the possibility that it might be used to drill a relief well. Additionally the Sedco 714, Total’s long term semi-submersible is also to be located in the area to be available to drill a relief well if necessary. Of course the pumping of heavy mud should take no more than a day or two, once it is mixed in the mud pits of the Rowan Viking, but the relief wells could take six months to drill. According to the media, Total have also hired the Skandi Aker a brand new well intervention vessel. It is a bit difficult to see exactly what this ship, which is set up for subsea work could do, although Total told the BBC that it might provide the means of killing the well. However it goes, one assumes that the Total management will be keeping their fingers crossed that the Wild Well Control guys will be able to sort the problem, and that the Elgin can start up again. When they were out there on 6th April they determined that there was no gas on the Elgin Platform itself, or on the access routes to the WHP, so just a bit of good news.

The rest of the UK oil industry will probably be keeping its fingers crossed as well. A rapid outcome would restore some confidence in an industry which has taken a few knocks since Macondo in 2010, and even now as I write, Shell’s share price is taking a bit of a dive as it is suggested that it could have a leak in the gulf of Mexico. But time is passing, and it is more than a week since there was last a press release from Total. Out in the North Sea there is still no-one on the Elgin or the Rowan Viking, the gas is still leaking, the income of the oil company has been reduced by millions of dollars a day, and there has been a considerable reduction in the gas available for use in UK. We can only wait as see what next week brings.

23rd April 2012

In the last couple of days there has been a bit of further information provided by Total. they say that the leak from their "G4" well has substantially reduced, and that their well kill activities are progressing on two fronts. The first is the relief well which has been spudded in from the Sedco 714, and preparation being made to make the Rowan Gorilla V available to drill a second relief well. The second string seems to be a well kill using the Skandi Aker, which is a sophisticated well intervention vessel. According to Aker Solutions this ship is capable of doing a number of things, firstly it can carry out well intervention on subsea wells, secondly it can be used for well stimulation, and thirdly is can carry out well testing and can flare off hydrocarbons or hold them on board. Indeed its only drawback in carrying out the job at Elgin might be the fact that any internal combustion engine can draw in gas, and run on it to the point of destruction. The ship is said to be in Peterhead at the moment being prepared for the task, so perhaps this problem is being dealt with.

Postscript.

Total managed to position the semi-submersible West Phoenix within range of the Elgin wellhead platform and regain control of the well using heavy mud. This is a quote from my May newsletter-

The latest news, on 15th May, is that the West Phoenix is in a position to commence killing the well with heavy mud via a temporarily installed flexible pipeline. This is known as a “dynamic well kill” for which permission was granted by the Department of Energy and Climate Change, on 4th May. If this job goes according to plan the well should be back under control in a day or two, and for those who are unfamiliar with these processes, the work is quite different from the attempt to kill the Macondo well in the Gulf of Mexico back in 2010. They are going to make, or maybe have already made, a connection to existing pipework on the deck of the Wellhead platform, as opposed to trying to stuff a pipe down end of a broken riser on the seabed several thousand feet down.

As things are now, in September 2012, it looks as if the platform may be operational again early next year.

Vic Gibson

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