As oil has become a scarcer resource, the search for it has, out of necessity, moved to more difficult locations. Oil companies have had to take a greater interest in inhospitable regions such as New Zealand's Great South Basin and the waters off Alaska. They are also drilling in water so deep that any problems are beyond the reach of divers. This increases the potential for severe environmental damage if companies do not have adequate safety back-ups. Clearly, that was the case with BP and its Deepwater Horizon platform in the Gulf of Mexico. Indeed, it is now apparent that the company has no real idea how to contain, let alone control, the giant oil spill prompted by an explosion at the rig almost six weeks ago.
BP had spoken confidently of solving the problem with a "top-kill" technique, which involved pumping thousands of barrels of drilling mud and other material into the well shaft to stifle the leak, before sealing it with cement. It estimated a 60 to 70 per cent chance of success. The outcome shattered any illusion that BP was anything like in charge of matters. The manoeuvre failed, as had three previous techniques designed to stop the flow. BP's next ploy, using a robot submarine to cut the pipe that is gushing oil and cap it with a funnel-like device will, at best, capture most of the oil. This has never been attempted at the depth of the well, 1.6km under the water, and BP is offering no odds on the chance of success.
The upshot of this ongoing failure is what the White House now says is the worst environmental catastrophe the United States has faced.
The Gulf spill has easily surpassed the Exxon Valdez disaster off Alaska in 1989, with estimates of the amount of oil leaking each day ranging from 1.9 to 3 million litres. The oil represents a long-term threat to the viability of Louisiana's delicate ecosystem and the livelihood of fishing communities, a situation exacerbated by the onset of the hurricane season. A hurricane might, by best-case scenarios, dilute the millions of litres of floating crude. It could also, however, push the oil deep into coastal marshes and estuaries. What BP says is the ultimate solution, a relief well that will permanently replace the destroyed rig, will not be ready until late August, well into the hurricane season.
Predictably, President Barack Obama has been receiving much criticism for what are BP's failings. If he has erred, it was in pledging to keep his Administration's "boot on the throat" of the oil company. In fact, his hands are largely tied. After the Exxon Valdez spill, Congress dictated oil companies would be responsible for dealing with major accidents - including paying for the clean-up - with oversight by federal agencies. That makes sense in terms of both accountability and oil company expertise and knowledge, which far outweigh anything Washington can provide. But what if the company does not know how to solve the problem?
In terms of oil exploration, the Deepwater Horizon's legacy must surely be a re-evaluation of safety programmes. Already, questions are being asked about Shell's plans to drill in the Arctic Ocean. The water there may not be as deep as in the Gulf of Mexico but there are other worries, including remoteness and limited ice-free seasons. Astoundingly, Shell's original safety planning included a designated spill-response centre that boasted merely a boat ramp.
This cavalier approach will no longer suffice. There is no choice but to venture into potentially troublesome territory to supply the world's continuing thirst for oil. But that process cannot mean the abandoning of reasonable safeguards. If so, there will surely be other environmental calamities to match that now facing the Louisiana coastline.