Troubled waters - the BP oil spill disaster
As the new columnist for Materials World I look forward to writing about the many positive aspects of the materials, minerals and mining industries. Sadly the loss of the Deepwater Horizon drilling rig and unfolding environmental disaster in the Gulf of Mexico are foremost in my mind this month.
Working in the upstream oil industry, I know how it is possible to lose control of an oil well. I am not going to speculate on the causes in this particular case, but it is clear that a catastrophic sequence of events occurred which normal drilling safeguards and emergency well control equipment failed to prevent.
In time the facts will become clear and we will understand the causes and learn the lessons. In the meantime we have to rely on what we read and hear in the media. I am always astonished at how ill-informed the popular media are about the oil industry, and how emotively most ‘oil’ stories are reported.
British energy company BP was developing the Macondo Prospect oilfield, leasing the rig from Transocean Ltd who are an offshore drilling contractor. The Deepwater Horizon drilling rig (not oil platform) was not ‘moored’ off the coast, it was dynamically positioned using GPS controlled thrusters. At a depth of 5,000ft it is too deep for conventional chains and anchors. The blowout was not caused by ‘a surge’ or ‘sudden spike’ in the reservoir pressure but a loss of hydrostatic head in the well.
Oil is now flowing (not spewing, gushing or pouring) from a length of drillpipe around which the blowout preventor (BOP) has possibly closed, but in this case failed to shear and effect a seal. The leak is not from an oil pipeline, the BOP is not an automatically triggered failsafe valve, and it is not ‘buried below the sea’. It is a series of hydraulically controlled rams located on the wellhead and designed to seal around, and in certain circumstances shear through, the drillpipe or whatever happens to be across the BOP at the time.
You may think I am being pedantic, and I am certainly not trying to make light of the disaster, but many people unfamiliar with the industry would be forgiven for thinking that drilling for oil and producing it from wells are one and the same. However, the differences are significant, not least the near mandatory use of sub-surface safety valves in the latter, which are located below the seabed and automatically failsafe in the event of loss of the wellhead. While it is essential that the industry learns exactly what went wrong and how to prevent it happening again, the public need to understand that with approximately 20% of every barrel of oil being used for everyday materials from tarmac roads, clothing and plastic water pipes to electric insulation, modern life simply cannot function without it.
I am no apologist for the environmental shortcomings of the materials, minerals and mining industries. But if those of us working in these fields do not challenge widespread inaccuracies and champion the facts, who will?