The tanker Exxon Valdez ran aground off the coast of Alaska in 1989, dumping 11 million gallons of crude oil into Prince William Sound in one of the worst oil spills in American history.

The oil industry’s response plans had promised a swift cleanup. But Riki Ott, a marine toxicologist, became alarmed when she flew over the wreck nine hours later.

“There was not a speck of promised recovery equipment on the water,” she told Retro Report. “This had all been promised within six hours, and we were three hours past six hours, and nothing.”

Investigators’ initial focus on the actions of the tanker’s captain delayed a response and obscured a series of safety failures that led to the spill. The accident exposed the inattention to regulation, inspection and safety standards in the oil industry.

Then in 2010, after a blowout on BP’s Deepwater Horizon rig caused a massive oil spill in the Gulf of Mexico, a presidential commission found that many lessons of the Exxon Valdez accident had been forgotten in the pursuit of offshore oil drilling.

BP paid more than $20 billion in penalties, and the Obama administration toughened safety rules for offshore drilling, some of which were later eased by the Trump administration.

Together, the two disasters reveal a pattern of unsettled standards and inconsistent oversight that environmentalists say raises questions about the industry’s preparedness for future oil spills.

“We were given blanket assurances about safety and spills,” after the Valdez spill, John Havelock, a former Alaska Attorney General told Retro Report. “In retrospect, I erred in not making sure that what was said was not put in writing.”

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