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Coast Guard officials grasped the potential threat of a catastrophic spill within hours of the explosion on board the Deepwater Horizon drilling rig, estimating that 8,000 barrels a day of crude oil could possibly gush out of the well in the event of a complete blowout, according to Coast Guard logs.

Over the first three days of the crisis — long before the public heard of a leak — the minimum estimate for a total well blowout ballooned eight-fold and the president was warned by his top aides that a major spill larger than the 1989 Exxon Valdez might be coming, according to the documents and interviews.

The logs, obtained by the Center for Public Integrity, provide the most detailed account of the early days of the BP disaster, and identify key events and notifications that were omitted from the White House’s official timeline of the crisis.

The estimate of the potential leak on April 21, the day after the rig exploded, reveals that first responders almost immediately understood the environmental threat to the Gulf of Mexico when Coast Guard officials detected the first signs of oil appearing on the Gulf waters.

“Potential environmental threat is 700,000 gallons of diesel on board the Deepwater Horizon and estimated potential of 8,000 barrels per day of crude oil, if the well were to completely blowout,” the Coast Guard reported on April 21, less than 24 hours after the accident was first reported.

Officials also learned within the first day of the disaster that the blowout preventer — an oil rig safety device that is supposed to cut off a well in case of an accident — was not functioning and could not be manually repaired by remote underwater robots.

“The second attempt of the ROV to shut-in the well has failed,” an entry at 11 a.m. CDT on April 21 read.

By April 23, the Coast Guard logs include a new estimate that a full blowout could result in a spill of 64,000 to 110,000 barrels per day, the logs show.

The leak estimates revealing an early awareness of a potential catastrophe are missing from the White House’s official timeline of the crisis.

That timeline first mentions a leak on April 24, four days after the explosion, when undersea robots discovered a plume of oil coming from the riser on the sea floor.

The White House has repeatedly rejected criticisms from both sides of the political aisle that it did not act quickly or decisively enough in the early days of the BP disaster, noting that the president on April 22 issued a public statement urging the federal government to make the accident its “No. 1 priority” and asserting that officials were worried about the environmental impact from the start.

White House spokesman Nick Shapiro did not respond to a questions from the Center submitted Tuesday about the logs. However, Shapiro told The New York Times that the White House timeline included a disclaimer at the bottom saying it was not meant to be comprehensive.

Shapiro also confirmed that in an April 22 meeting, Coast Guard Admiral Thad Allen told President Barack Obama that as soon as he saw the Deepwater Horizon oil rig on fire, he knew oil was likely to start gushing into the Gulf of Mexico. At that same meeting, Shapiro said, Interior Secretary Ken Salazar told the President this event could eclipse the amount of oil spilled during the Exxon Valdez.

The logs were provided to the Center by Rep. Darrell Issa of California, the senior Republican on the House Oversight and Government Reform Committee. The Center shared them with The New York Times.

“Less than 48 hours after the explosion, multiple attempts to activate the blowout preventer had already failed and the Coast Guard knew 8,000 barrels of crude oil spilling into gulf waters each day was a real possibility,” Issa told the Center.

“Americans have a right to be outraged by this spill, by top government officials caught off-guard, and by the facts the White House omitted in explaining what it knew and when it knew it,” he said.

The logs show that Coast Guard officials comprehended the possible scope of the spill nearly a week before an estimate was released measuring the leak at 5,000 barrels a day. That estimate led to an escalated response by the government.

Coast Guard officials declined to comment about the logs. Officials from the Homeland Security Department did not respond to phone calls and email messages.

The logs detail the failed attempts to repair the blowout preventer on the sea floor, which was spewing oil that also fueled the fire on the rig. The logs also show that, as an extensive and wide-ranging search and rescue mission unfolded, the size of the oil slick was growing daily on the ocean’s surface, though Coast Guard officials believed that the oil was mainly being burnt off in the fire.

“There was a reported sheen while the MODU (mobile drilling unit) was afloat. However, the majority of the pollution was being mitigated by the fire,” read a Coast Guard entry dated 1:26 pm CDT on April 22. By that time, estimates of a visible oil sheen measured 16 square nautical miles.

A day earlier, a smaller sheen was detected.

“Sheen size is as follows: 2 miles by ½ mile, with 50 percent coverage with color ranging from dark to barely visible. The amount is estimated to be 30 gallons,” states a Coast Guard log entry dated 11:15 a.m. CDT on April 21. It said the sheen was first spotted at 10:10 a.m. that morning.

Additionally on April 22, a Coast Guard craft returning from a rescue mission spotted signs of a possible natural gas leak after the rig sank, further evidence that hydrocarbons might be leaking. “On return to home base, discovered what appeared to be a large area of bubbles in water, possible natural gas leak,” says a log entry dated the evening of April 22.

By early the morning of April 23, the Coast Guard had already flown five sorties and applied 1,500 gallons of dispersant to locations where sheens were reported, according to the logs, though officials that same day said the well appeared to be not leaking.

The White House timeline doesn’t mention any of the earlier sheens but does note on April 22 that 100,000 gallons of dispersant were “prepositioned” for use in the Gulf and “preapproved” by regulators “despite a lack of apparent leak.”

The logs, however, show the pre-positioning of the dispersant occurred after the oil sheens had already been discovered, the blow-out preventer was determined to be broken, and the first sorties launched to apply dispersant. The first dispersant flight departed at 2:43 p.m. CDT on April 22, according to an internal timeline kept by the Coast Guard.

The first mention on the White House timeline of any oil sheens occurs April 23 — two days after the first slicks were detected — when the timeline notes “an oil sheen was reported with approximately 8,400 gallons estimated on the water and there was no apparent leak.”

In contrast, the Coast Guard logs talk openly on the first day about a free flow of oil and about efforts by the rig’s owner, Transocean, to use a remote vehicle to stop the flow.

“Transocean is developing a plan to stop the flow/fire using an ROV” the logs note on April 21.

Conflicting reports seemed to complicate what appeared to be a simple chain of events: the rig continued to gush up until the moment it sank, making a leak seemingly inevitable.

On the morning of April 23, an undersea robotic vehicle reported that the valve on the blowout preventer had closed, sealing off the well, though that report was found to be false several hours later, the logs show.

The confusion in these reports may explain why the Coast Guard stated publicly that day that there appeared to be no leak.

Despite that report, BP began to establish an incident command post on April 23 “to prepare for potential release,” estimating that a release of 64,000 to 110,000 barrels a day could occur “if the well were to completely blowout.”

Coast Guard officials have repeatedly stated that they were preparing for a worst case scenario, and initially ordered a variety of oil response vessels to come to the scene, including a team that is assigned to respond to oil spills.

Oil skimming began and continued during the efforts to find the 11 workers who were initially missing and later presumed dead — efforts that were also complicated by what appears to be misinformation and false leads.

On the morning of April 22, members of the unified command held a phone conference to discuss the potential spill if the rig sank, which it did less than two hours later.

Around mid-day, aircraft flying over the spill reported a sheen of sixteen square miles, but added that “it wasn’t as bad as they imagined,” the logs state.

At a press conference that afternoon, Rear Admiral Mary Landry said that the oil on the surface appeared to be residual from the fire, though she raised the possibility that the gallons of diesel fuel on board might have begun leaking after the rig sank.

The next day, as the search for the missing 11 workers came to a close, Admiral Landry, possibly misled by the erroneous early report, said that it appeared that the blowout preventer had worked.

“It is not a guarantee,” she said at a news conference, “but right now we continue to see no oil emanating from the well.”

The understanding that oil was not leaking at the wellhead is corroborated by the logs, though at the time, a survey of the entire riser, which was still attached to the blowout preventer, had not been completed.

Coast Guard officials did caution that there was still uncertainty surrounding the status of the blowout preventer, but continued to view the 180,000 barrels of oil and water mix on the surface as residual from the days the rig was on fire.

On the morning of Saturday, April 24, an undersea robot noticed “a small quantity of unknown material” emanating from the drill pipe, which is encased in the riser.

After surveying the leak, it was determined that 1,000 barrels a day were pouring from the riser.


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