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Today on day 81 of the disaster, an estimated 4 million barrels of oil would have spilled into the Gulf of Mexico and the end to the oil gush is still no where in sight. At today’s price of 75 USD per barrel, more than 300 million USD had been flushed into the sea. BP has spent more than 3 billion USD on the recovery efforts so far and still counting. BP’s investors lost even more in billions, as BP’s share value dropped more than 50% from its high of over 60 USD per share to less than 30 USD recently.
As oil continues to gush out from the ill-fated Macondo well at more than 50,000 barrels a day, the causes of the disaster are still in question. While the Obama Administration is battling with the Gulf states on the moratorium on deepwater offshore drilling (>500m water depth), oil producing countries are holding their breath and oil companies continue business as usual.
Could a BP’s style disastrous oil spill happen in South-East Asia? It is not a question of IF but when. If the threat of a disastrous oil spill is imminent, should we then not try to avert it or be more prepared for the containment following the disaster? Should we not be concern of the environmental damages and its financial woes about to hit our shores?
As oil industry’s standards and regulations in the US and Australia, are much higher than in South-East Asia, disasters of this nature should have happened more often in this region if it is only the question of industry and safety standards. Why would the worst of oil spill disasters in recent years occur in the better regulated countries? Montara disaster on 21 August 2009 in the Timor Sea, offshore Australia and Macondo disaster on 20 April 2010 in the Gulf of Mexico, offshore USA?
Before we jump with joy, let’s look more closely why no major oil spill (BP’s style) has yet occurred in South-East Asia?
First and foremost, the recent disastrous oil spills all occurred at deeper waters close to the shelf-edges (see figure 1 and 2). The shelf edge zones are more hazardous to drilling not only because of deeper water depths (>500m) but because of the presence of abnormally weak highly fractured-faulted stress zone at the upper rock formation immediately underlying the Quaternary sedimentary deposits; collectively termed as Gas-saturated Weak Sub-Formation (GWSF) zones. GWSF hazards are less hazardous within the shallower shelf zone because of shallower depths and gentler slopes. Still we did have blowouts and we learned to handle them over time.
As the shallower and cheaper (easier) to exploit oil reserves get depleted, oil exploration in South-east Asia will intensify in the shelf-edge zones. Figure 3 shows the shelf-edge zones that are currently the most promising prospects. If we are to avoid the costly mistakes of PTTEP and BP’s oil spill, we must learn the root causes of the disasters and not the superficial political excuses[1].
Deep water wells require advanced drilling technology. But while modern drilling techniques are credited to preventing more blowouts, they are also the reason why mega oil spills occur.
As recent as 10 years ago, most wells would have blown at the GWSF hazardous zones. Now with advanced drilling technology, many of the wells “safely” bored through the GWSF hazardous zones without blowing out, to reach their high-pressured gas/oil reservoirs thousands of metres below. Unfortunately, gases (even at low pressure) do cause cavitations in the overlying unconsolidated sediments, as they escape into the water column. Drilling mud invasion into the highly fractured rock formation can seriously undermine the cementation of the top-hole section. “Damaged” geotechnical conditions beyond the immediate vicinity of the wells are not normally monitored. Abnormal drilling losses, complicated well cementation, erratic test results and gas influxes such as those observed while drilling the Macondo Well, are indicative of the problematic GWSF zones.
Given the high daily costs (>1 million USD/day) of drilling operation, the pressure to drill and complete the well in the shortest time possible is understandable for any oil company. Suppressing the blowout at shallow depths however only postpone and compound the disastrous consequence to the next higher cost level.
In BP’s case, more than 81 days of massive oil spill. It took more than 3 months for PTTEP to control Montara’s oil spill in the Timor Sea. In Total’s 1988 Sisi-2 blowout in the Straits of Makassar, offshore Kalimantan, there was no oil spill as the well blew after drilling less than 900m below the sea floor. The well collapsed into a crater swallowing the whole drill ship and continued to bubble out gas for a few weeks. In the 1991 Shell’s Barton BT05 blowout, previous drilling mud and cement were spewed out with the gas since the well had only intercepted an undetected feeder fault and not the gas/oil reservoir hundreds of metres below.
Delayed Blowouts as the name implies do not occur instantaneously as “normal blowouts” do when a well is drilled into a high pressured gas pockets or abnormally high-pressured formation. That is why Delayed Blowouts are difficult to understand just as Cancer, AIDS and other slow-acting diseases were initially misunderstood in Medicine.
The PTTEP’s Montara blowout occurred more than a year after the platform was installed. At BP’s Macondo well, the blowout (20 April 2010) occurred almost 2 months after Deepwater Horizon had resumed drilling the well in Feb 2010. The well was first drilled by Transocean Marianas semi-submersible rig on 7 Oct 2009 but was aborted at 4023 feet (1226 m) below seabed on 29 Nov 2009 when the rig was damaged by Hurricane Ida (Wikipedia & various sources).
Reports of localised subsidence at some of the offshore producing platforms within the shelf edge zone are particularly disturbing. Localised subsidence up to a few km in diameters, are unlikely to be associated with reservoir depletion but more likely due to problems associated with the shallower GWSF hazardous zones. These platforms would be prime candidates for future blow-outs and oil spill disasters.
But not all future oil spill disasters need to be triggered by man-made blowouts. There are many potential submarine landslides on the deeper shelf slopes just waiting to fail. Evidence of past giant landslides is evident from sea floor down to as deep as few hundred metres below. With the recent spate of earthquakes in the region, it is only a matter of time.
Is there any hope of us averting a BP’s style oil spill disaster? Are the oil companies and the governments not worried of another mega-oil spill and their high clean up costs? Are they as clueless as the mainstream public or simply “tidak apa” (could not care less) on the disastrous effect on our marine environment, the Armageddon of the marine world? Isn’t prevention better than the cure?
Believe it or not, the oil industry does have a first line of defence against disasters. Geohazards Site Surveys are specifically commissioned to seek out geohazards for each and every well or platform location. But in reality, this line of defence against disasters is a badly broken one; brought about by years of easy profits, vested business interests and pandering to the whims and fancies of the oil companies rather than being an independent watch-dog. Hidden from public scrutiny, the geohazards industry was having an easy ride on the waves of windfalls from the meteoric rise in oil prices. Mega disasters like BP’s oil spills are inevitable consequences of the “Oil Bubble” and its past exuberance just like the global financial meltdowns from the housing bubble, credit crunch and Ponzi schemes.
The offshore oil industry is often thought as being infallible with stringent HSE regulations and strict code of conduct, all in the name of safety and preservation of the environment. The BP’s Oil Spill disaster busted that myth and confirmed our worst fears. BP’s Oil Spill disaster publicly confirms what many professionals in the industry had long known and feared in silence.
It is human nature to ignore early warning signs of potential hazards; just as 90% of you reading this article would dismiss this imminent threat of another mega oil spill disaster. Even if a mega disaster had been accurately predicted, trying to avert it is like trying to stop a speeding train from its collision course, miles before the actual collision.
Would any geohazards specialist be brave enough to stand by his/her geohazards prediction or give in to expediency? The typical geohazards prediction given for the ill-fated Macondo’s well was intentionally ambiguous, designed to allow BP to proceed with the drilling while providing some defensive cover in the event of some “problems”. It cleverly evades the question of a disaster; by meaninglessly ranking the risk of encountering gas from “negligible to moderate”, from top to bottom, far and wide (see extract below).
Imagine paying hundreds of thousands of dollars only to have a generalized standard assessment that is almost the same for every site, save for the numbering and sequencing. It reflects the depth of insignificance this once important role of geohazards prediction had sunk into.
Imagine paying thousands of dollars for a fire inspector to report to you that your house is at a moderate risk of fire for using gas in the house. The presence of gas is not the question but the piping condition and potentially hazardous leaks are. The risk of encountering gas is less important than the quantity, distribution, pressure and nature of occurrence in relation to the geological structure. If the gas occurrence is assessed to be potentially hazardous then the assessment needs to define the means by which drilling could have triggered or developed the situation into a blowout or disaster. In addition, the geohazards assessment should have recommended the best alternative in averting the potential problems, blowout or disaster which is the primary objective. The cheapest way of averting a disaster is to relocate the well location.
Geohazards surveys and geohazards predictions are not as easy as currently practiced worldwide. The oil companies and the world have been short-changed into accepting “half-past six” geohazards assessment and playing Russian roulette with our lives and our environment. Is it unreasonable to demand for a more reliable and accurate geohazards interpretation without the “cover all” ambiguities?
There is a simple solution. Less than 20% of all sites surveyed are at risk of any immediate short term geohazards. A QC review of past geohazards reports by a knowledgeable and experienced geohazards expert can quickly isolate the risky well or platform locations for more detailed assessment. For risky wells that had not been drilled yet, safer alternative locations can be found while for platforms already in place, detailed trajectory risk analysis can be carried out to minimize the risk of a disaster. For locations at risk of landslides, the solution will be more difficult since significantly larger areas are involved. Nevertheless, it is better to face the situation now than later; after a disaster has occurred.
Life is about choices; resolve it now or postpone it to a later date at a much higher cost. BP’s oil spill disaster is another warning sign that the worst is yet to come. Given the many unreported problems of production wells sited dangerously at the (shelf) edge (pun intended), the next oil spill disaster need not necessarily be triggered by a drilling mishap. So far very few in the oil industry recognized the potential disasters that could result from induced or natural occurrence of giant submarine subsidence, landslides and earthquakes in the vicinity of the production platforms. If an oil giant could teeter on the brink of financial collapse, what hopes do poor third world countries have in the face of a massive oil spill disaster? More booms, anybody?
[1] The root causes of BP’s oil spill & the imminent threat of more oil-related disasters. BK Lim, 1 July 2010
