E-mails and letters obtained by ProPublica show that the main contractor BP was using to check its facilities, Acuren, employed inspectors who weren't certified to perform their jobs and may not have been properly trained. The certification issues affected at least 19 inspectors responsible for more than 13,000 locations along the line and were serious enough that they were reported to BP's board of directors in London.

Pascal, a career Environmental Protection Agency attorney only seven weeks into her retirement, knew as much as anyone in the federal government about BP, the company that owned the well. She understood in an instant what it would take others months to grasp: In BP's 15-year quest to compete with the world's biggest oil companies, its managers had become deaf to risk and systematically gambled with safety at hundreds of facilities and with thousands of employees' lives.

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