According to reports, the gas cloud surrounding the platform and accompanying sheen contains between two and 23 tonnes of gas condensate, measuring six nautical miles in length.
Bellona is deeply concerned about the gas leakage at the platform 240 kilometers east of Aberdeen. A gas cloud was seen rising from Elgin PUQ platform in the North Sea and is visible 11 kilometers away.
“This is a gas blowout that is out of control and is going to be so for a long time, Bellona President Frederic Hauge said.
The Bellona Foundation has established a special team that is following the leak closely.
Total admitted Tuesday, after several reassurances that the leak would have no environmental consequences, that the well would be “difficult to bring under control” – raising the specter of a Deepwater Horizon take two in the North Sea.
As the news started to pour into the Bellona offices on Monday night, the information became more and more alarming.
“The information we have right now indicates that it will be very challenging to prevent a blowout. This is a critical situation that is out of control,” Hauge said.
Jake Molloy, the head of the section of the UK union that represents offshore oil and gas workers, agreed telling Reuters that A separate relief well may need to be drilled to ease pressure and allow emergency teams to regain entry to the rig and try to fix the problem.
“The well in question had caused Total some problems for some considerable time … a decision was taken weeks ago to try to kill the well, but then an incident began to develop over the weekend,” said Malloy.
“Engineers have told me that it is almost certain that gas is leaking directly from the reservoir through the pipe casing,” he said – something Hauge had pointed out might be the case early Monday morning.
Three oil platforms – the Elgin, Shell’s Shearwater and nearby Rowan Viking drilling rig have evacuated a total of 323 workers – 238 from Elgin alone.
The Elgin/Franklin reservoirs are located off the coast of Aberdeen, Scotland in an area of high petroleum activity. The fields are linked. The area contains a large field with wells up to 6000 meters deep and that hold extreme pressure and temperature.
During the drilling of Elgin/Franklin in 2003, world records for pressure and temperature were broken as engineers found reservoir pressures between 600 and 1100 bar and temperatures reaching 200 degree Celsius. By comparison, the Deepwater Horizon blowout occurred at 896 bar. The field on which the platform is located was discovered in 1991.
Bellona has learned that there have been incidents at the well that have veered dangerously close to accidents, including a serious incident in 2005. Other grave safety shortcomings have also been revealed in this field.
Total was, in fact, considering killing the well when the problems began over the weekend.
“The well in question had caused Total some problems for some considerable time [...] a decision was taken weeks ago to try to kill the well, but then an incident began to develop,” Malloy was quoted by the BBC as saying.
Elgin identified as a problem well
According to Hauge, the Elgin/Franklin is “the well from hell.”
The incident leading up to the bubbling disaster started early on Sunday morning at Elgin platform when workers discovered a well control problem.
They noted a blue sheen on the water’s surface and bubbles from boiling water beneath the platform. The leak was already so large Sunday by 12:15 that 219 non-critical personnel were evacuated to Aberdeen, leaving a skeleton crew of 19 aboard the platform.
Crews from Elgin, other platforms evacuated
Those left behind tried to gain control of the leak but were unable. The well was completely downmanned at 2:30 on Monday – appoximately 14 hours after the incident started
After the evacuation, a no-fly zone of three nautical miles around the well was established. Coastguards said shipping was also being ordered to keep at least two nautical miles away.
Shell also evacuated 52 of the 90 workers aboard Shearwater platform – which is attached to the Noble Hans Deul platform by a 10 meter bridge – leaving 38 onboard.
Petroleum company Total E & P United Kingdom (TEP United Kingdom) operates the Elgin/Franklin platform and Rowan Viking rig, which was connected to Elgin. Total E & P told Bellona that both the platform and the rig are intact and confirmed that all crew have been evacuated to the mainland.
Impossible to stop
In Bellona’s analysis, the discharge at the Elgin field is going to be very difficult to stop. When the gas escapes it becomes impossible to get back on board the platform to deal with it. Gas in the water affects the buoyancy of possible rescue rigs, and the water is flammable.
Bellona does not know today how much gas is left in the part of the reservoir where Elgin is situated, but the foundation is sure that this leak will increase in scope.
When gas and condensate coming from depths as great as 5000 meters at high pressures rises, they will expand exponentially on their way to the surface. Sand and debris will dig holes in metal near the bore hole. If the gas is moving outside of the well, it will dig further and further into the bore’s rise.
Problematic relief wells
Bellona believes that when a platform is evacuated, the only remaining measure to bring the situation under control is drilling a relief well – as was done at Deepwater Horizon, the BP oil blowout in the Gulf of Mexico in 2010.
But Bellona fears this may difficult if not impossible. Such a well must be drilled very deep depending on how deep the leak in the Elgin well is. To dig the relief well, workers must somehow drill in under the leak and put in a new plug. Doing this depends on using highly advanced platforms in a nearly surgical procedure that can take months.
High gas concentrations in the area are telling as they shows how far from any platform a relief well must be drilled.
But with buoyancy and flammability issues to consider, any rig drilling a relief well would have to do it from a great distance. To get a rig any closer than 10 kilometers, said Hauge, rescue workers would have to set the gas in the sea on fire.
But if there are platforms available to drill from such distance and this deep, the question that remains is will they do it? This, thinks Bellona, will be very difficult to arrange. Platforms of this nature would first have to be released from their current contracts, which will take time, as such highly specialized rigs are used for drilling other complex wells. Drilling for the relief well alone could then take as long as three months if not far longer.
So task number one at the moment, says Bellona, is to immediately secure a drilling platform that is capable of drilling the relief well. If such equipment is available, it must immediately be requisitioned.
If drilling a relief well is not possible, the only solution is the worst-case scenario of letting the reservoir blow out until all of its pressure is tamped down. As the quantity of gas in the reservoir is unknown, fears that large amounts remain are well founded. This gas would then be released into the water and air over a long period.
The environmental consequences of this accident could be substantial. Having large amounts of hydrocarbons in water and on the surface is not desirable. It will not look like an oil spill, but the hydrocarbons released will have many of the same dramatic effects. Bacteria, for instance, ingests hydrocarbons and hence consumes enormous amounts of oxygen in the water. Blue condensate sheen on the surface of the water will destroy the plumage of sea foul.
Should the situation develop to the point where all the gas from the reservoir is released, it will lead to major emissions of greenhouse gasses: When unburned natural gas enters the atmosphere, its detrimental effect on the atmosphere is 20 times worse than that caused by CO2.
Difficult choices ahead
The coming days will lead to difficult choices as Total struggles to bring the leak under control. If the worst case scenario does indeed occur, it must be considered whether setting fire to the spill is not the best course of action. This too will have environmental consequences, putting Total and the British government between the devil and the deep blue sea.
The Elgin/Franklin accident bears similarities to the Deepwater Horizon blowout, the only real difference being that Elgin is pumping gas condensate and not crude oil into the sea. The Rowan Viking rig is a brand new platform launched in 2010 and considered – like the Deepwater Horizon rig – to be state of the art for the drilling industry.
Rough conditions in the North Sea
The drilling was taking place under difficult conditions, with extreme pressure, high temperatures and great depths of the reservoir. Drilling in such circumstances involves enormous gambles: In situations like this, there are no ready-made solutions for dealing with the worst-case scenario, as Deepwater Horizon showed.
Similarities to oil accidents
The disaster now bearing out at Elgin/Franklin also bears similarities to the accident at Norwegian Statoil’s Gullfaks C platform in 2010. There too, Bellona had previously asked questions about the possibilities of drilling relief wells should gas leaks occur.
Fortunately, there have so far been no injuries or deaths in the current leak. But Bellona fears what unpleasant questions this accident will raise and what answers Total will be able to supply for them.
Sigurd Enge, Advisor
Magnus Borgen, Head of Communications