A deadly surge of methane gas was the culprit behind the oil rig explosion that left 11 workers dead and threatens the Gulf Coast, according to an internal investigation by BP. The report, described by the Associated Press, includes interviews with BP executives who, in a dark coincidence, were on board the rig at the time of the blast to celebrate their sterling safety record. Robert Bea, an engineering professor at UC-Berkley familiar with the interviews, described how the gas shot a plume of seawater 240 feet into the air out of the drill column right before the deadly blast. "What we had learned when I worked as a drill rig laborer was swoosh, boom, run," Bea said. "The swoosh is the gas, boom is the explosion and run is what you better be doing." The gas was created by a chemical reaction from setting cement, beginning as a small bubble and picking up size and power along the way up the column.