Deepwater Horizon — BrandWiki

Deepwater Horizon

Overview

Deepwater Horizon

owner	Transocean's Triton Asset Leasing
operator	BP
registry	* Panama (23 February 2001 – 28 December 2004) * Majuro (29 December 2004)
identification	* ABS class no.: 0139290 * Call sign: V7HC9 * * MMSI no.: 538002213
route	Gulf of Mexico
ordered	December 1998
builder	Hyundai Heavy Industries
original cost	US$560 million‡R1R‡‡R2R‡
way number	89
laid down	21 March 2000
completed	2001
acquired	23 February 2001
maiden voyage	Long Beach, California – Freeport, Texas
out of service	20 April 2010
fate	Sank on 22 April 2010, after an explosion and fire
notes	Located in the Gulf of Mexico at a depth of 5000 ft at °N, °W‡R3R‡

Deepwater Horizon was an ultra-deepwater, dynamically positioned, semi-submersible offshore drilling rig owned by Transocean and operated by the BP company. On 20 April 2010, while drilling in the Gulf of Mexico at the Macondo Prospect, a blowout caused an explosion on the rig that killed 11 crew and ignited a fireball visible from 40 mi away.[4] The fire was inextinguishable and, two days later, on 22 April, the Horizon collapsed, leaving the well gushing at the seabed and becoming the largest marine oil spill in history.[5]

Built in 2001 in South Korea by Hyundai Heavy Industries, the rig was commissioned by R&B Falcon (a later asset of Transocean),[6] registered in Majuro, and under lease to BP

History

Construction and ownership

Deepwater Horizon was built for R&B Falcon (which later became part of Transocean)[16] by Hyundai Heavy Industries in Ulsan, South Korea.[10] Construction started in December 1998, the keel was laid on 21 March 2000,[17] and the rig was delivered on 23 February 2001,[17] after the acquisition of R&B Falcon by Transocean.[1] Until 29 December 2004, the rig was registered in the Republic of Panama.[18]

Transocean, through its Steinhausen, Switzerland[19] subsidiary[20] Triton Asset Leasing GmbH,[21][17] operated the rig under the Marshallese flag of convenience.[22] The rig was leased to BP by a three-year contract for deployment in the Gulf of Mexico after construction.[23] The lease was renewed in 2004 for a year,[24] 2005 for five years,[25]

According to R&B Falcon's filings to SEC in 2001, the transfer document between R&B Falcon and Transocean was dated 17 August 2001,[28] and the rig was specified as "official registration number of 29273-PEXT-1, IMO number of 8764597, with gross tonnage of 32,588 and net tonnage of 9,778"[28] and the transfer value as US$340 million.[28] As of 2010, the rig was insured for US$560 million covering the replacement cost and wreckage removal.[29]

Drilling operations

Deepwater Horizon worked on wells in the Atlantis (BP 56%, BHP 44%) and Thunder Horse (BP 75%, ExxonMobil 25%)[30] oil fields. It was described at times as a "lucky" and "celebrated" rig, and in 2007 was still described as "one of the most powerful rigs in the world".[31] In 2006, it discovered oil in the Kaskida oil field and, in 2009, the "giant" Tiber oil field.[32][33] The well in the Tiber field had a true vertical depth of 35050 ft and a measured depth of 35055 ft, below 4132 ft of water. The well was the deepest oil well in the world[33]

Regulation, safety, and inspection

The Minerals Management Service (renamed on 18 June 2010, to the Bureau of Ocean Energy Management, Regulation and Enforcement, or Bureau of Ocean Energy (BOE))[47] is the regulatory and inspecting body for offshore oil drilling and rigs in the United States of America.[47] According to an Associated Press investigation, certain safety documentation and emergency procedure information, including documentation for the exact incident that later occurred, was absent.[46] The exact number of required monthly inspections performed varied over time; the inspections were performed as required for the first 40 months, but after that about 25% of inspections were omitted,[46] although the investigation notes this is partly expected, since there are circumstances such as weather and movement which preclude an inspection.[46] Reports of the last three inspections for 2010 were provided by Freedom of Information legislation.

Explosion and oil spill

At 7:45 p.m. CDT on 20 April 2010, during the final phases of drilling the exploratory well off the gulf of Mexico, a geyser of seawater erupted from the marine riser onto the rig, shooting 70 m into the air. This was followed soon by the eruption of a slushy combination of drilling mud, methane gas, and water. The gas component of the slushy material quickly transitioned into a fully gaseous state and then ignited into a series of explosions and then a firestorm. An attempt was made to activate the blowout preventer, but it failed.[48] The final defense to prevent an oil spill, a device known as a blind shear ram, was activated but failed to plug the well.[49]

Ten workers were presumed killed by the initial explosion:

An eleventh worker also died in the subsequent fire, a crane operator:

115 workers survived with 17 injured.

The rig was evacuated, with injured workers airlifted to medical facilities. After approximately 36 hours, Deepwater Horizon sank on 22 April 2010. The remains of the rig were located resting on the seafloor approximately 1500 m deep at that location, and about 400 m northwest of the well.[50][51][52]

The resultant oil spill continued until 15 July when it was closed by a cap.[53] Relief wells were used to permanently seal the well, which was declared "effectively dead" on 19 September 2010.[54] NOAA established the Gulf Spill Restoration project, administered by the Deep Water Horizon National Resource Damage Assessment Trustees, to help to restore much of the coastline.[55]

Jason Anderson, 35, of Midfield, Texas;
Donald Clark, 49, of Newellton, Louisiana;
Stephen Ray Curtis, 40, of Georgetown, Louisiana;
Gordon Jones, 28, of Baton Rouge, Louisiana;
Roy Wyatt Kemp, 27, of Jonesville, Louisiana;
Karl Kleppinger Jr., 38, of Natchez, Mississippi;
Keith Blair Manuel, 56, of Gonzales, Louisiana;
Dewey Revette, 48, of State Line, Mississippi;
Shane Roshto, 22, of Liberty, Mississippi;
Adam Weise, 24, of Yorktown, Texas.

Aaron Dale Burkeen, 37, of Philadelphia, Mississippi.