Natural gas accident at North Sea looking very dangerous

I did not even realize until today that an abandoned gas platform owned by TOTAL had suffered a major accident and is releasing massive and dangerous amounts of methane to the sea and atmosphere near Norway and Scotland. 

Worst is that the operation to stop the leak may well be of the dimension of what happened with the Blackwater Horizon in the USA. The only thing not that bad is that, methane being a gas, it will not directly pollute as much as oil and needs no dispersants. 

The very bad thing is that it is a very flammable gas and if sufficient amounts are released it could well ignite accidentally, creating a huge burst. Hypothetically a sufficiently large methane bubble could be catastrophic, and some have argued it to be a cause of mass extinctions in the past (however this kind of leak is surely too small). 

But The Guardian discusses today that an explosion would be cause of major pollution and damage for the local sea life. Also the methane is not pure but is mixed with hydrogen sulphide which is very poisonous:

Martin Preston, marine pollution specialist and honorary research fellow at the University of Liverpool, said that from an environmental standpoint, both greenhouse gas emissions and local fish deaths were a concern. "The methane release represents a very significant explosion hazard, and of course methane is a potent greenhouse gas. The gas in this field is 'sour gas' – ie it contains hydrogen sulphide which is very poisonous to humans and aquatic life – so localised risks to marine life are likely. The hydrogen sulphide content of the current release is unclear at present. Localised fish kills cannot be ruled out."

My biggest concern is indeed that it may get complicated to fix the leak and there is serious risk of massive deflagration, which would kill workers and aggravate the problem. 

That's what the Mail Online argues today, remembering the Piper Alpha catastrophe of 1988, which killed 167. More than 200 workers have been evacuated already. 

The options considered are the same as for the Deepwater Horizon catastrophe near Louisiana two years ago: sealing the leak with a concrete-mud mix (so-called dynamic killing) or drilling a relief well nearby and extracting the gas that way. TOTAL pretends to believe that the leak may well die off on its own but sounds like wishful thinking and stock-market damage minimization strategies in my humble opinion.

It looks like yet another serious problem ahead.