Updated

A summary of events on Saturday, May 29, Day 38 of the Gulf of Mexico oil spill that began with the April 20 explosion and fire on the drilling rig Deepwater Horizon, owned by Transocean Ltd. and leased by BP PLC, which is in charge of cleanup and containment. The blast killed 11 workers. Since then, oil has been pouring into the Gulf from a blown-out undersea well at a rate of at least 210,000 gallons per day.

TOP KILL

A BP executive says the risky procedure to stop the oil spewing into the Gulf of Mexico has yet to show much success, and BP is considering scrapping it in favor of a different method to contain the worst oil spill in U.S. history. The comments from BP PLC chief operating officer Doug Suttles came amid increasing skepticism that the "top kill" operation — which involves pumping heavy drilling mud into a crippled well 5,000 feet underwater — would halt the leak. So far, the top kill hasn't stopped the leak — and Suttles said he's not sure if it will. If the top kill fails, BP would cut off the damaged riser from which the oil is leaking and cap it with a containment valve that's already resting on the seafloor. BP is already preparing for that operation.

THE INVESTIGATION

Coast Guard and Minerals Management Service officials heard a sixth day of testimony during hearings into the disaster in Kenner. Most of the testimony centered around the explosion and the chaos that ensued. David Sims, BP's drilling operations manager for exploration and appraisal in the Gulf of Mexico, testified he was aware of well problems experienced by the Deepwater Horizon's drilling crew in the weeks and months leading up to the explosion. He said there were no serious problems the day the rig exploded.

LOW ESTIMATES?

At nearly every step since the Deepwater Horizon exploded more than a month ago, causing the worst oil spill in U.S. history, rig operator BP PLC has downplayed the severity of the catastrophe in the Gulf of Mexico. On almost every issue — the amount of gushing oil, the environmental impact, even how to stop the leak — BP's statements have proven wrong. The erosion of the company's credibility may prove as difficult to stop as the oil spewing from the sea floor. BP has been slow to acknowledge the leak was likely much worse than the public had been told, and such behavior has led to accusations that it has been motivated to keep the leak estimate low because under federal law the size of eventual fines is tied to the size of the leak.