About 2, 400 barrels of oil had escaped through the well bore, seeped up into the rock, then escaped through fissures in the seafloor.

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Oil and gas companies use traditional horizontal drilling techniques to bore into the land were gas is trapped.

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These provide access to the central bore of the well underneath most of the heavy valves which should have closed off the flow of oil, but for some reason did not.

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And following the intersection of the well bore with those relief wells, they will put heavy mud down there to suppress the pressure of the oil coming up from the reservoir, put a cement plug in and effectively do what I would call a bottom kill, as opposed to the top kill, which was not successful a couple of weeks ago.

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