BP has finished pumping cement into the blown-out Macondo well in the Gulf of Mexico as part of its efforts to permanently plug the source of the nation's worst oil spill, the company said Thursday.
Engineers started the cementing operation at 10:15 a.m. EDT and completed it at 3:15 EDT. It was the second step in the "static kill," in which heavy mud was first pumped into the well from the surface to stop it from leaking crude into the gulf.
BP said in a statement that the static kill procedure will "complement" a separate effort to plug the well through a relief well that is nearing completion in a technique known as the "bottom kill."
Earlier, the company announced that retired Coast Guard Adm. Thad W. Allen, the national incident commander for the disaster, had authorized the cementing operation, which was under consideration following the successful effort to pump mud into the well.
The development comes a day after the Macondo well became an apparently harmless hole in the seafloor, clogged with 13-pound-per-gallon gunk, and barely more of a threat to spew oil into the Gulf of Mexico than to start gushing lemonade.
On the 107th day of the Deepwater Horizon disaster, the well that tormented the nation had flatlined. Federal officials then green-lighted the cementing of the well, already jammed with mud, late Wednesday. Federal waters are reopening gradually to fishing. The oil slick, the once-horrific expanse of red-orange mousse and silver sheen, has largely disappeared, federal scientists said Wednesday, even though the amount of oil left is more than four times that dumped by the Exxon Valdez.
The Obama administration breathed a sigh of relief, holding a midday news conference featuring top officials who claimed credit for guiding BP in getting the well under control. Officials hastened to remind the public that Macondo won't be incontrovertibly dead until a relief well drills into it near its base and plugs it with cement. But even the cautious Allen, the official in charge of the federal response to the disaster, called the static kill a "fairly consequential" event and a "very significant step."
About three-quarters of the nearly 5 million barrels of oil that escaped Macondo has evaporated, dissolved or been dispersed by chemicals, skimmed by boats, burned, weathered and, most important, devoured by the Gulf of Mexico's permanent oil-eating microbial workforce, according to a study released Wednesday by the National Oceanic and Atmospheric Administration and Interior Department.
"Mother Nature is assisting here considerably," said NOAA administrator Jane Lubchenco.
This should terminate, once and for all, the more apocalyptic scenarios for the demise of the gulf and the spread of oil to Atlantic shores. There is no sign that the oil is going to ride the Loop Current onto the beaches of South Florida, the Outer Banks, Bermuda, Ireland and so on.
Just a month ago, the spill was an uncontrolled calamity: Macondo mocked the technological skills of the world's petroleum engineers, and oil was slathering birds and turtles and tar-balling hundreds of miles of coastline. The turning point came when BP put a new tight-fitting cap on the well July 12 and closed the valves three days later, cutting off the ugly geyser of oil that had become a dominant image of the summer.
Federal scientists have said that vigilance would be called for even after the static kill procedure worked, which, according to BP in a 2 a.m. announcement, it did. BP sent out a bulletin declaring success after spending eight hours pumping mud into the well from surface ships.