Read Fire on the Horizon Online

Authors: Tom Shroder

Fire on the Horizon (14 page)

BOOK: Fire on the Horizon
6.62Mb size Format: txt, pdf, ePub
ads

When it was over, most of the guys on the rig just felt relief. They wouldn’t miss the two-hour helicopter commute out to this more than usually distant spot. Some did feel pride at the congratulatory e-mail messages sent to the crew, and the words of praise from both Transocean and BP managers.

But the accomplishment may have seemed even more significant to those who had no idea what it took to drill a well in ultradeep water. As the news was broadcast around the globe—the deepest well ever!—it was taken by many as particularly stunning evidence that technology had conquered the monumental challenges and hazards of offshore drilling. The Tiber Field triumph was an exclamation point to the rising sentiment that offshore drilling had become so advanced, it was virtually fail-proof.

CHAPTER TEN

LATCHING UP

February 2010

Block 252, Mississippi Canyon, Gulf of Mexico

Nature provides no shortage of elaborate, even bizarre mating rituals. The fierce head-butting of elk bulls in rut, the four hundred distinct mating chirps of the grasshopper, even the female praying mantis’s habit of decapitating the male during copulation and ingesting his head—all are astonishing in their own right, but they pale in comparison to what happened above the Macondo well on February 9, 2010.

After the Marianas was towed away for repair on Thanksgiving Day, it took some tinkering and horse trading and a few more lost months before Transocean’s drilling schedule could be rearranged and another company asset could be redirected to Block 252 in the Mississippi Canyon. That turned out to be Deepwater Horizon, which was the first available of the twenty-two Transocean ships or rigs capable of drilling in ultra-deep water. The dynamic positioning operator on the Horizon’s bridge input the GPS coordinates of the Macondo wellhead, and the computer pointed the rig in the
right direction and fired the thrusters. That part was simple. But after the Horizon reached its destination, things got considerably more complicated.

The Marianas had left Macondo a 3,900-foot-deep, steel-lined hole to nowhere. The well was less than a third completed and topped by a metal funnel that stuck up just above the ocean floor. The assemblage resembled a supersize version of one of those funnel and tube combinations used to pour gas from a five-gallon jug into the empty tank of a stranded car. In this case, the purpose of the funnel, otherwise known as the wellhead, was to receive the protruding 27-inch diameter male end of the 325-ton blowout preventer dangling from the end of a 5,000-foot steel string attached to a vessel bobbing in the waves high above.

To conceive how difficult it is to drop the BOP stack’s connector pipe into the well’s hole, first imagine standing on the observation deck of the Empire State Building and attempting to lower a soda bottle at the end of a 1,200-foot-long string into a garbage can on the sidewalk. It’s extremely windy, and you’re wearing roller skates. Now consider that, with the building encased in clouds, it’s impossible to see the sidewalk, much less the garbage can.

Imagine an observer with a cell phone at the bottom giving directions as the bottle descended. Every motion made by the person on the observation deck would take time to translate down the long string, and the effect on the bottle of his movements interacting with the swirling winds would be virtually unpredictable.

But all of that would be easy compared with what the crew of the Horizon was attempting to accomplish. Instead of a thousand feet of insubstantial air to contend with, they were dealing with 5,000 feet of water exerting 2,300 pounds of pressure on every square inch of surface area. An assistant with a cell phone wearing even the most advanced scuba gear would be dead before he got a
fifth of the way to the bottom. Even a nuclear submarine would be crushed like a grape about halfway down. And instead of simply unspooling a string, the Horizon’s drilling crew would have to assemble, piece by piece, 75-foot segments of 19½-inch-diameter steel pipe weighing more than 30,000 pounds each, and feed them slowly through the center of a moving rig.

Before any of that happened, they had to locate the wellhead. This wasn’t as easy as motoring to the coordinates locked into their GPS system. The GPS coordinates referred to a point on the surface of the ocean and were all but useless in locating a precise point 5,000 feet down. For any practical purpose, there was no “straight down” in the Gulf of Mexico. “Straight” was a theoretical concept rendered all but meaningless by the constantly swirling currents and the prodigious distance, just as there was no dropping a bottle on a string “straight down” from the Empire State Building.

But the Horizon could do a lot better than an assistant with a cell phone.

 

The rig spent a few days over Macondo taking the opportunity to inspect and maintain its nine-year-old blowout preventer, the same one that had launched with the rig from Korea. Not only did the crew’s livelihoods depend on a properly functioning blowout preventer; so too did their lives. But the only time it could be inspected and maintained was when it was on deck between wells.

Once the subsea engineers were satisfied with the condition of the BOP, they got to work on the elaborate preparations necessary before they attempted to lower it to the wellhead. First the marine crew hooked acoustic beacons to the grating of a steel cage about the size of something that might have been used to punish a troublesome prisoner in a Soviet gulag. The cage was then lowered
over the side by a large winch spooled with ten thousand feet of umbilical cable. The cable whirred off the spool interminably. It took a full hour before the cage had descended nearly a mile, to one hundred feet above the sea bottom. Finally the winch yanked the cable to a halt. The cage door opened and something very like a giant hermit crab snuck out. This was an ROV, or remotely operated vehicle. The ROV was equipped with powerful head lamps, video camera eyes, and mechanical arms that gave it that crab look. One of the arms had a cutter where a crab’s pincher would be. The other arm had a grabber, which could be manipulated to grasp and use a variety of simple tools, like a scooper, a squeegee, or a pressure washer.

An umbilical cable with the ROV’s power, hydraulic control, and video lines snaked back up to the rig and connected to the ROV shack—basically a shipping container furnished with comfortable chairs, video screens, telephones and, best of all, joysticks. The joysticks not only controlled the ROV’s movements, but also operated the lights, camera, and the machine’s arms.

Being an ROV operator was a video gamer’s dream job—a 3-D entertainment that wasn’t virtual, but real. Not surprisingly, the ROV operators tended to be young video game enthusiasts who could turn the ROVs in intricate loops and work wonders with the mechanical arms. Either that, or they were older men, invariably small in stature, who had gotten wet to drive the submersibles themselves back in the 1990s, when anchored rigs worked comparatively shallow water and the tiny machines were manned. Either way, both the old and the young operators were geniuses at what they did, and the rig would be nearly helpless without them.

For the moment, the ROV’s task was to locate the wellhead and surround it with five sonic buoys that would allow the dynamic positioning operator to pinpoint its exact location rela
tive to the surface. When the ROV emerged from its cage, the operator switched on its sonar. Because of the currents buffeting the crane cable on the trip down, there was no telling where the ROV had ended up, or even what direction it was facing. They watched the sonar screen as the ROV slowly rotated. A blip appeared—almost certainly the wellhead. They switched on the lights and the camera, and drove the submersible in the direction of the sonar blip. The powerful lights on the ROV pushed back the total blackness of the depths. After a few minutes that seemed much longer, the bulk of the wellhead appeared on the screen. The ROV closed the remaining distance and scurried around the wellhead, inspecting it from all angles with its camera. Grasping the pressure-washing tool, the ROV sprayed off the mud that had settled atop the steel. The ROV operator peered at his video screen, looking for the carpenter’s bubbles welded to the wellhead. If the wellhead had sunk unevenly into the mud, the BOP wouldn’t be able to latch on properly, and the whole effort would have been wasted.

When the bubble appeared on the camera, it was squarely within the level lines. All was as it should be. The ROV could swim back to its cage.

Now the Horizon slowly motored a thousand feet north of the wellhead and hovered. The ROV reemerged and focused its cameras on the cage and the acoustic beacons hanging from the side. They were four-foot-tall steel tubes, four inches in diameter, each containing an extremely sensitive underwater microphone, and each spliced to a rope anchored with a cement block. The ROV used one hand to grab the spliced rope and the other to cut the line securing the buoy cylinder to the cage. Then, still grasping the rope, it swam down to the bottom, placed the weight on the seafloor, and let go of the rope. It returned to its cage, the rig moved
to another position a thousand feet from the wellhead, and the procedure was repeated until the wellhead was surrounded by a pentagon of sonic buoys.

Only three of the buoys were required for the triangulation that would give an accurate position of the wellhead. The fourth was there in case one of the other sonic buoys stopped functioning, and the fifth was there to back up the backup. Nobody wanted to have to repeat this process.

When all the buoys were in place, the ROV was cranked back to the surface, and the rig’s transponder, hanging from a pole beneath the pontoon, began to ping the five buoys in sequence. With each ping, the lock on their positions grew slightly more precise. The calibration was complex and dependent on water temperature, salinity, and a host of other variables. For it to succeed, the sea had to be completely quiet. If a workboat was tied to the rig delivering supplies, it would be sent out of range; if workers were striking hammers they would be asked to stop. Sometimes a whale would be cruising the region, making an underwater racket. The whale couldn’t be ordered away, of course, so the crew just had to wait for it to leave on its own. Nothing could be allowed to drown out the distant echo of the beacons.

The calibration was painstaking and complex, but the hard part wouldn’t really begin until it was complete.

The first step was to get the BOP in position, suspended above the water over the rig’s “moon pool”—the hole in the center of the rig directly beneath the derrick that might, hypothetically, reflect the moon on a clear night. The crew unbolted the BOP from the deck, where it had been fastened since being hauled up from the last well, sitting on top of a hydraulically powered cart that looked like a half-scale flatcar. Now the cart inched along a track carrying its enormous burden toward the edge of the moon pool, where the
tracks took a left turn out over thin air. A gantry rose up to encase the BOP and lock on from either side.

Photographic Insert

Deepwater Horizon, one of the most powerful industrial machines ever built.

Doug Brown at home with his wife, Meccah, and daughter, Kirah. (
Courtesy of Doug Brown
) Jason Anderson as the “Sea Baby” during the Horizon’s “Shellback” ceremony in 2001. (
Tyson Cullum
) Dave Young in his dorm at SUNY-Maritime, circa 1995. He expected to sail a ship, not an oil rig. (
Cindy Konrad
) Captain Curt Kuchta on the Horizon, circa 2009. (
Courtesy of Curt Kuchta
)

BOOK: Fire on the Horizon
6.62Mb size Format: txt, pdf, ePub
ads

Other books

Centralia by Mike Dellosso
Super by Ernie Lindsey
After Alex Died by Madison, Dakota
Futile Efforts by Piccirilli, Tom
Seeing a Large Cat by Elizabeth Peters
Waiting by Ha Jin
Always by Celia Juliano
Unexpected Christmas by Samantha Harrington