BP Oil Rig Survivor: 'All the things they told us could never happen... happened.'

In an exclusive interview with 60 Minutes, Mike Williams, the Deepwater Horizon's Chief Electronics Technician in charge of the oil rigs computers and electrical systems, provides a first-hand account of what happened in the run-up to the sinking of the Deepwater Horizon oil rig in the Gulf of Mexico that has resulted in the largest environmental disaster in history.

Williams provides startling information about the Blow Out Preventer which is used to seal the well shut in case of a blow-out. As 60 Minutes investigative journalist Scott Pelley puts it:

"It's the crews only hope."

Due to a crew mishap a key component of the Blow Out Preventer was damaged prior to the Deepwater Disaster.

Williams: "They found chunks of rubber in the drilling fluid. He [the crew member] thought it was important enough to grab this double handful of chunks of rubber and bring them into the driller shack.

I recall asking the supervisor if this was out of the ordinary. And he said, 'Oh that's no big deal.' And I thought how can this not be a big deal there is chunks of our seal now missing."

And if that wasn't enough one of the control panels on the Blow Out Preventer had lost some of its functions weeks before.

Here's the first of three parts in this exclusive 60 Minutes investigation:

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