Published: Jul 06, 2010 3:43 AM EDT
Updated: Jul 06, 2010 12:44 AM EDT

HOUSTON (AP) - A former Pemex engineer in charge of deepwater drilling operations during a 1979 oil spill in the Gulf of Mexico says BP may need both relief wells it's drilling to contain the gusher in the Gulf.
BP is more confident that the first relief well should do the job. It's expected to be completed in early August. The oil company is drilling a second relief well, viewed as a backup, that should be done a few weeks later.
But Carlos Osornio, now a deep drilling consultant, says one well may not be enough to contain the high volume of oil.

A reduction in pressure would allow BP to put a new blowout preventer on the blown well, but that isn't a foolproof plan. A Rice University professor says that's because the condition of the blown well isn't known.