Transocean Deepwater Horizon Explosion-A Discussion of What Actually Happened?

The trouble with the way that the news is presented and consumed is that major events are delivered in ‘headline’ style and even something as terrible as the oil spill in the Gulf of Mexico is starting to compete with other, more current, news stories.

The other issue with news channels is that it is uncommon to be presented with a real insight into the human scale of massive catastrophes.  Thank goodness for the web!

Drilling Ahead is a website that describes itself as A Social Network of Oil & Gas Professionals. Another website find courtesy of Naked Capitalism.

On Drilling Ahead is a report about the loss of the Deepwater Horizon.  It makes both gripping and chilling reading.  Here’s an extract but it’s much better to read it directly from here:

An Ill-fated Discovery
According to news accounts, at about 10 p.m. CDT last Tuesday, Deepwater Horizon was stable, holding an exact position in calm, dark seas about 45 miles south of the Louisiana coastline. Water depth in the area is 5,000 feet. The vessel manifest listed 126 souls on board.

Deepwater Horizon was finishing work on an exploration well named Macondo, in an area called Mississippi Canyon Block 252. After weeks of drilling, the rig had pushed a bit down over 18,000 feet, into an oil-bearing zone. The Transocean and BP personnel were installing casing in the well. BP was going to seal things up, and then go off and figure out how to produce the oil — another step entirely in the oil biz.

The Macondo Block 252 reservoir may hold as much as 100 million barrels. That’s not as large as other recent oil strikes in the Gulf, but BP management was still pleased. Success is success —
certainly in the risky, deep-water oil environment. The front office of BP Exploration was preparing a press release to announce a “commercial” oil discovery.

This kind of exploration success was par for the course for Deepwater Horizon. A year ago, the vessel set a record at another site in the Gulf, drilling a well just over 35,000 feet and discovering the 3 billion barrel Tiber deposit for BP. SoDeepwater Horizon was a great rig, with a great crew and a superb record. You might even say that is was lucky.

But perhaps some things tempt the Gods. Some actions may invite ill fate. Because suddenly, the wild and wasteful ocean struck with a bolt from the deep.

The Lights Went out;
and Then...

Witnesses state that the lights flickered on the Deepwater Horizon. Then a massive thud shook the vessel, followed by another strong vibration. Transocean employee Jim Ingram, a seasoned
offshore worker, told the U.K. Times that he was preparing for bed after working a 12-hour shift. “On the second [thud],” said Mr. Ingram, “we knew something was wrong.” Indeed, something was very wrong.

Within a moment, a gigantic blast of gas, oil and drilling mud roared up through three miles of down-hole pipe and subsea risers. The fluids burst through the rig floor and ripped up into the gigantic draw-works. Something sparked. The hydrocarbons ignited. In a fraction of a second, the drilling deck of the Deepwater Horizon exploded into a fireball. The scene was an utter conflagration.

And here’s another extract:

Damon Bankston to the Rescue

Fate was not entirely cruel that night. Indeed, a supply boat was already en route to the Deepwater
Horizon. It was the Tidewater Damon Bankston, a 260-foot long flat-deck supply vessel.

Damon Bankston heard the distress signal. Her captain did what great captains do. He aimed the bow toward the position of Deepwater Horizon. Then he tore through the water, moved along by four mighty Caterpillar engines rated at 10,200 horsepower. Soon, the Damon Bankston arrived on scene,
sailed straight into the flames and joined the rescue.

Meanwhile, Coast Guard helicopters lifted off from pads in southern Louisiana, and Coast Guard
rescue vessels left their moorings. “You have to go out,” is the old Coast Guard saying. “You don’t have to come back.”

The helicopters flew in the black of night toward a vista of utter disaster. Arriving on scene, the pilots watched in awe as columns of flame shot as high as a 50-story building. The helicopters were buffeted by blasts of super-heated wind coming from the flames, while chunks of soot the size of your hand blew by.

The pilots hovered in the glow of the blazing rig, while Coast Guard medics fast-roped down to the deck of Damon Bankston . The medics quickly assessed the casualties, strapped critically injured crewmen to backboards and hoisted them up to the helicopters. Then the pilots turned north and sped ashore to hospitals.

Uninjured survivors returned to land on the Damon Bankston. And others came out to fight
the blistering flames.

But the Deepwater Horizon wasn’t going to make it. The situation deteriorated, to the point of complete catastrophe. The ship was lost.

At about 10 a.m. CDT on Thursday morning, 36 hours after the first explosion, the Deepwater Horizon capsized and sank in 5,000 feet of water. According to BP, the hulk is located on the
seafloor, upside-down, about 1,500 feet away from the Macondo well it drilled.

The full report on the Drilling Ahead website covers much more than these extracts. Do read it in full – and ponder on what these very brave souls went through.

UPDATE: For those that have an engineering interest in this terrible incident, Yves Smith of Naked Capitalism published an ‘insiders’ Guest Post on the 13th.  Do read it – fascinating.

By Paul Handover

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