"Static Kill" Growing as Option to End Gulf Oil Spill Drama
Tuesday 20 July 2010
BP wants to try a 'static kill' in the Gulf oil spill – similar to the failed 'top kill' – to stopper the top of the well until relief wells kill it from below. A decision could come as soon as Wednesday.
No news is good news for BP as its jerry-rigged containment system is holding the renegade Macondo well at bay for a sixth day in a row, meaning that US authorities could soon give the go-ahead to a “static kill” that could finally end the now three-month-long Gulf oil spill drama.
The consideration of a "static kill" is a sign of growing confidence in the new cap. It suggests that officials do not think the new cap is causing new leaks that could make the surrounding seafloor unstable.
Retired Coast Guard Adm. Thad Allen, who is leading the federal relief effort, dismissed concerns about seepage near the well. The largest leak – two miles from the site – is now believed to be related to a different well. Other smaller leaks detected closer to the well are like "drips" that don't yet indicate anything wrong with the well.
Instead, pressure is continuing to build within the well – an "encouraging sign" that the well below is not severely damaged, Allen said.
That has led BP to consider the so-called "static kill" procedure, which in some ways resembles the earlier, failed “top kill” effort. But BP senior vice president Kent Wells said Tuesday that the fact that the well is currently contained means it presents far fewer challenges than when it was blowing at near full-steam during the previous attempt.
“Unlike the ‘top kill,’ where we had to pump at high rates and pressure, that is not required with the ‘static kill,’ ” Mr. Wells said. “We would start pumping at low rates and pressure and after we get some mud in the hold the pressure would start to go down. So you very quickly start seeing benefits as opposed to risk.”
Wells said the "static kill" would not replace the completing of relief wells but supplement it. While the relief well drill bits could breach the well casing as early as next week, it could take several weeks to permanently seal the well. "Static kill" could stopper the well securely in the meantime.
If “static kill” is approved by the unified incident command, which is led by Allen, BP would go ahead as quickly as possible. That decision could come as early as Wednesday.
Government scientists want to be assured that built-up pressures from the containment cap won’t damage the well casing, potentially leading to another major setback – including the possibility of oil and gas leaking up uncontrolled from the seabed.
As of Tuesday afternoon, the pressure in the well was 6,834 pounds per square inch. Ideally, engineers had hoped for pressures to build to 9,000 psi, which would indicate that all the oil was staying within the column of the well bore and pressing up against the cap – not leaking into the surrounding bedrock.
Scientists are unsure whether the lower reading suggests that some oil is leaking out of the well bore or if all the oil that has escaped into the Gulf has simply eased pressures within the reservoir.
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Talking about oil, which we were...
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