Shell outlines precautions for offshore Arctic drilling
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Shell Oil Co. is making its best case for why drilling in the offshore Arctic can be done with fewer potential problems than what confronted BP in the Gulf of Mexico.
In a detailed response to the federal Minerals Management Service’s request for more assurances, Shell promises to deploy near the drilling sites in the Chukchi and Beaufort seas a prefabricated coffer dam capable of containing a blowout -- this time, unlike the dome that failed in the Gulf of Mexico, a device designed to avoid a buildup of ice crystals.
Critics continue to insist that there are far too many unanswered questions to proceed with drilling in the frigid, fragile Arctic, home to threatened and endangered polar bears, bowhead whales and countless other wildlife whose survival often hangs by a thread.
“When I’ve been listening to the stories about the Gulf of Mexico, all I can think is that something like this happening in the Arctic would be devastating,” said David Barber, chair of Arctic system science at the University of Manitoba.
“The Arctic is a sensitive system, and the reason it’s sensitive is there aren’t a whole lot of alternatives for the organisms that live there. If you really affect one part of it dramatically, they can’t go somewhere else to do something differently.”
Read further for other measures Shell said it has put into place after examining the Gulf of Mexico incident:
Those measures include: --Reservoirs will be carefully evaluated for pressure, fluid content and temperature before full-scale coring gets underway in a bypass hole, reducing the risk of a ‘kick’ or unwanted flow in the original wellbore.
--Testing of the blowout preventers will be conducted every seven days, instead of every 14 days.
--A subsea remote operating panel will be installed on top of the blow out preventers that can be operated manually by divers or a remote-controlled submarine in case it doesn’t work automatically.
--The company will be prepared to apply dispersant underwater, at the source of any oil fill, but only if it obtains the necessary emergency permits.
Shell emphasized there are important differences between exploration in Alaska and in the deep waters of the Gulf of Mexico:
--Instead of drilling in 5,000 feet of water to a depth of 18,000 feet, as with BP’s Deepwater Horizon well, Shell will be drilling in 150 feet of water, at a depth of up to 8,000 feet in the Chukchi and up to 10,200 feet in the Beaufort.
--The pressure encountered is expected to be much less than that found in the Gulf well, probably no more than 6,000 psi, compared to about 15,000 psi in the Gulf. ‘Our biggest safety advantage is the water depth that will allow us to detect and respond to an event quickly and appropriately,’ Shell said, and even in the case of the failure of a drilling riser, the remaining fluid below the seafloor ‘would effectively stop any well flow in such a low-pressure system.’
Recent industry studies have shown that in some cases, cold water temperatures and ice such as exists in the Arctic for long parts of the year could actually help contain spilled oil and make it easier to clean up.
But critics insist it’s a big unknown.
“If a spill were to happen off the coast of the North Slope, maybe 500 miles or so in broken or light ice conditions, it could realistically be days or weeks before anyone could even get to the source of the spill,” said Joe Cunningham, research engineer with the NOAA-funded Coastal Response Research Center in New Hampshire.
“The other problem is since the Arctic is such a new environment for oil spill operations, we’re kind of relying on equipment that was developed for warm water use. There hasn’t been a lot of study done on how that same equipment will operate under Arctic conditions.”
The Pew Environment Group, in an analysis of Shell’s oil spill response capability, said important shortfalls remain.
‘Shell lists a few major response vessels, a few thousand feet of boom and about 30 small work boats that would form the basis of their in-region response,’ the group said, adding that the main oil spill cleanup industry co-op on the North Slope, Alaska Clean Seas, based about 240 miles away from the Chukchi drilling site in Prudhoe Bay, does not appear to have the necessary equipment to do offshore cleanup.
‘A major spill would require bringing in boats, trained personnel, boom, skimmers, aircraft and dispersants from all over the U.S. Shell does not specify how or when these resources would be mobilized to the remote Arctic,’ Pew said.
The nearest airports to Shell’s Chukchi drilling location capable of handling a large cargo plane are at Barrow, 100 miles away, and Point Hope, 150 miles away. Barrow is 2,000 miles from the nearest major potential supply city, Seattle.
Ron Morris, general manager of Clean Seas Alaska, an oil industry co-op that manages oil spill response across the North Slope, said in an interview that the organization has $50 million worth of oil response equipment and at least 36 trained professionals on duty at all times who already have responded to a large number of oil spills, mostly small ones, across the region.
The teams train regularly to respond to offshore spills, but with only a limited number of offshore wells operating so far, their work has been mainly theoretical. They are, however, accustomed to working in the deep cold, sometimes minus 80 degrees, of the Arctic winter.
“They might have to go out and work 10 to 15 minutes, and then come in for half an hour to warm up,” he said.
Pew also raised questions about Shell’s assertions that a blowout in the shallow, 150-foot-deep waters of the Arctic would be quite unlikely. The group cited a 2007 study by the Minerals Management Service that it said found that of offshore blowouts between 1992 and 2006, shallow water blowouts were the most common.
‘Nineteen of the 39 blowouts in this period occurred in water depths of zero to 200 feet,’ it said.
-- Kim Murphy