Today, N.O.A.A. senior scientist told Congress that he was wrong about how much oil gushed into the Gulf, how much remains and conceded almost all of it is not accounted for, days after academic researchers ripped his two-week-old report to shreds. Documents reveal BP is withholding information from Transocean regarding the April 20 explosion that caused the gusher.

A U.S. government senior scientist admitted today before Congress that “that three-quarters of the oil that gushed into the ocean from BP’s broken well was still in the Gulf of Mexico, repudiating his own earlier assurances that the worst of the spill was over,” Suzanne Goldberg reported at the London Guardian.

Bill Lehr, a senior scientist at the National Oceanographic and Atmospheric Administration (N.O.A.A.) wrote a report two weeks ago “which suggested the majority of the oil had been captured or broken down”, she added. The report estimated about 25% o the oil remained in the Gulf the rest had been skimmed, dispersed or had dissolved.

Today, Dr. Lahr said before the U.S. House Energy and Commerce Committee that he estimated 4.1 million barrels of oil gushed from BP’s Deepwater Horizon rigged well that exploded April 20, down from his initial estimate of 4.9 million, “noting that 800,000 barrels were siphoned off directly from the well”, Ms. Goldberg reported, adding:

By some estimates as much as 90% of the oil was unaccounted for. Lehr said 6% was burned and 4% was skimmed but he could not be confident of numbers for the amount collected from beaches. […] Meanwhile in an article for the journal Science, experts from the Woods Hole Oceanographic Institute mapped a 22-mile plume of oil droplets from BP’s well, providing the strongest evidence to date of the fate of the crude.

Earlier this week, two research teams affiliated with U.S. universities countered the initial N.O.A.A. estimates, stating most of the oil remained in water and were hugging the floor or deep enough to not be visible from overhead.

A team from the University of Georgia stated they believed 70-79% of the oil was underwater and a team affiliated with the University of South Florida believed the “a constellation” of oil was coating the floor.

Transocean, the company that owned the rig, “is accusing BP of withholding what it describes as critical evidence needed to investigate the cause of the worst offshore oil spill in U.S. history, according to a confidential internal document obtained by The Associated Press [A.P]”. (via The Raw Story)

The explosion caused the deaths of eleven workers on the rig and the letter to BP’s lawyers added, according to the A.P. report: “This is troubling, both in light of BP’s frequently stated public commitment to openness and a fair investigation, and because it appears that BP is withholding evidence in an attempt to prevent any entity other than BP from investigating the cause of the April 20 incident and the resulting spill.”

They are attempting to obtain “16 pieces of technical information from BP, including pressure tests, logs, and other data”, the report added.

Three internal investigations over the last decade suggested that BP “repeatedly disregarded safety and environmental rules and risked a serious accident if it did not change its ways”, ProPublica reported in June, adding that “similar themes” persisted in other documents and communications obtained by the investigative journalism firm.

In May, Jad Mouawad at The New York Times outlined a long history of BP ignoring safety and was repeatedly blaming Transocean for the April 20 explosion.