Crystals stymie oil leak fix
Tar balls washing up on Gulf island
ON THE GULF OF MEXICO – A novel but risky attempt to use a 100-ton steel-and-concrete box to cover a deepwater oil well gushing toxic crude into the Gulf of Mexico was aborted Saturday after ice crystals encased it, an ominous development as thick blobs of tar began washing up on Alabama’s white sand beaches.
The setback left the mission to cap the ruptured well in doubt. It had taken about two weeks to build the box and three days to cart it 50 miles out then slowly lower it to the well a mile below the surface, but the frozen depths were too much for it to handle.
Still, BP officials overseeing the cleanup efforts were not giving up just yet on hopes that a containment box – either the one brought there or a larger one being built – could cover the well and be used to capture the oil and funnel it to a tanker at the surface to be carted away. Officials said it would be at least Monday before a decision was made on what next step to take.
“I wouldn’t say it’s failed yet,” BP Chief Operating Officer Doug Suttles said. “What I would say is what we attempted to do … didn’t work.”
There was a renewed sense of urgency as small bits of tar began washing up on Dauphin Island, three miles off the Alabama mainland at the mouth of Mobile Bay and much farther east than the thin, rainbow sheens that had so far arrived sporadically in the Louisiana marshes.
About a half dozen tar balls had been collected by Saturday afternoon at Dauphin Island, Coast Guard Chief Warrant Officer Adam Wine said in Mobile. Authorities planned to test the substance but strongly suspected it came from the oil spill.
In the three weeks since the Deepwater Horizon rig exploded on April 20, killing 11 workers, about 210,000 gallons of crude a day has been flowing into the Gulf. Until Saturday none of the thick sludge – those iconic images of past spills – had reached Gulf shores.
It was a troubling turn of events, especially since the intrepid efforts to use the containment box had not yet succeeded. There has been a fascination with the effort to use the peaked box the size of a four-story house to place over the ruptured well. It had taken more than 12 hours to slowly lower it to the seafloor, a task that required painstaking precision to accurately position it over the well or it could damage the leaking pipe and make the problem worse.
It was fraught with doubt and peril since nothing like it had been attempted at such depths with water pressure great enough to crush a submarine. It ended up encountering icy crystals, familiar territory for deepwater drilling.
The icy buildup on the containment box made it too buoyant and clogged it up, BP’s Suttles said. Workers who had carefully lowered the massive box over the leak nearly a mile below the surface had to lift it and move it some 600 feet to the side. If it had worked, authorities had said it would reduce the flow by about 85 percent, buying a bit more time as a three-month effort to drill a relief well goes on simultaneously.
Options under consideration included raising the box high enough that warmer water would prevent the slush from forming, or using heated water or methanol to prevent the crystals from forming.
The spot where Deepwater Horizon rig once was positioned is now teeming with vessels working on containing the well. There are 15 boats and large ships at or near the site – some being used in an ongoing effort to drill a relief well, another with the crane that lowered the containment device to the seafloor.
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