BP took shortcuts on blown-out well: lawmakers

"It appears that BP repeatedly chose risky procedures in order to reduce costs and save time and made minimal efforts to contain the added risk," said Representatives Henry Waxman and Bart Stupak, the top Democrats on the House of Representatives Energy and Commerce Committee.

BP opted for a well design with few barriers to impede a "kick" of methane gas that surged up the drilling pipe and set off a catastrophic series of explosions in the Gulf of Mexico on April 20, and failed to ensure that the drill pipe was adequately sealed with cement to prevent an influx of flammable gas, the lawmakers said.

The lawmakers disclosed the details in a letter to BP Chief Executive Tony Hayward, who is slated to testify before the committee on Thursday. BP declined to comment on the letter.

"It would be inappropriate to comment on these matters in advance," BP spokesman Toby Odone said in a written comment. "No doubt they will raise these matters during the hearing."

The letter presents a potentially damning account of key decisions made by BP drilling officials in the days before the catastrophic explosion of the Deepwater Horizon rig that killed 11 workers and eclipsed the 1989 Exxon Valdez disaster as the worst U.S. oil spill.

The letter, a synthesis of facts gathered by the Energy and Commerce Committee's investigations panel, portrays BP engineers as under the gun and in a hurry to wrap up drilling operations, which were running more than 40 days late.

To drill the well, BP leased the Deepwater Horizon rig from Swiss-based Transocean at a rate of about $500,000 a day, and the drilling delays meant an extra $21 million in leasing fees, lawmakers said.

In some cases, BP ignored warnings from contractors like Halliburton Co and their own employees and chose faster and cheaper drilling options, they said.

On April 15, five days before the explosion, BP drilling engineer Brian Morel wrote in an email to a BP colleague: "This has been (a) nightmare well which has everyone all over the place."

On April 16, BP opted for a minimal number of "centralizers" in the well that were meant to ensure that the casing ran straight to aid the cement in setting properly.

Halliburton suggested that BP use 21 centralizers to reduce the potential for gas to flow into the well casing, but BP decided to use only six even though Halliburton warned of a "SEVERE gas flow problem."

When informed that extra centralizers were available in Houston and could be flown to the rig the same morning, BP well team leader John Guide responded, "It will take 10 (hours) to install them .... I (am) very concerned about using them."

BP drilling engineer Brett Cocales emailed Morel,"But, who cares, it's done, end of story, will probably be fine and we'll get a good cement job.

"So Guide is right on the risk/reward equation."

Lawmakers said BP had flown a team of engineers from Schlumberger Ltd to the rig to perform a cement bond log to ensure that the cementing job was adequate, but decided not to use their services.

BP flew a crew from Schlumberger to the rig on April 18, but told them on the morning of April 20 that their services were not required, lawmakers said. The decision "may have been driven by concerns about expense and time," the lawmakers said.

The Schlumberger crew flew off the rig at 11:15 a.m. on April 20.

At 9:53 p.m. that evening, the rig exploded, and sank a mile beneath the Gulf of Mexico two days later.

(Reporting by Chris Baltimore; editing by Jackie Frank and Mohammad Zargham)