Posted on Sat, Jul. 24, 2010
last updated: March 15, 2013 11:58:34 AM
WASHINGTON — Drilling rigs were returning to the scene of the Deepwater Horizon oil catastrophe Saturday after Tropical Storm Bonnie weakened and no longer posed a threat to efforts to kill the runaway well permanently.
In a conference call with reporters, retired Coast Guard Adm. Thad Allen, the Obama administration's point man on the disaster, said he expected the Development Driller III, the rig that is drilling the primary relief well, to be in a position to resume drilling operations in 24 to 36 hours.
Allen said the first effort to kill the well permanently by pouring heavy drilling mud into lines connected to the well's blowout preventer is likely to begin within three to five days. He said that pressure continues to build in the containment cap that has kept oil from flowing into the Gulf of Mexico since July 15 and that government scientists "have confidence" that the well is not leaking oil into the seabed.
He said Bonnie's winds, once above 39 miles per hour, may have dropped to 30.
Dr. Jane Lubchenco, the head of the National Oceanic and Atmospheric Administration, said that Bonnie wasn't expected to regain strength. She said waves at the Deepwater Horizon site weren't expected to exceed eight feet — well within the rigs' limits.
The weakening of the storm also made it unlikely that oil floating below the surface of the Gulf would be brought to the surface, Lubchenco said. She said the passage of the storm was likely to break any sheets of oil on the surface into smaller pieces, and that larger waves would "redistribute" oil and tarballs on beaches. "In some cases, the beaches may look cleaner as a result of this redistribution," she said.
Allen said he estimated that Bonnie had set back efforts to permanently kill the well by seven to nine days. However, he described a sequence of events to take place in the next few days that indicated that the runaway well is near its death, after nearly three months of gushing millions of barrels of oil into the Gulf.
He said that it would take 24 to 36 hours for the Development Driller III to be back in position over its relief well. Then he said it would take technicians eight to 12 hours to reconnect 5,000 feet of pipe to the relief well's blowout preventer on the seafloor. After that, technicians would remove a plug that they had placed in the well when they evacuated the site, redeploy the drill bit and install a final length of casing pipe to reinforce the relief well.
While the cement around that final casing is drying, Allen said, technicians on the Q4000 drilling rig on the surface would begin the "static kill" procedure, pouring drilling mud into the Deepwater Horizon's blowout preventer in an effort to force the oil and gas back into the reservoir 18,000 feet below the sea's surface.
If that's successful — Allen said technicians will know within 48 hours — the relief well, once completed, would be used to pour cement into the Deepwater Horizon well and seal it permanently.