Deepwater Horizon - and the Gulf of Mexico

I haven't been sharing much info on this environmental disaster...it's been all over the papers, but now I'll start a feature which points out where all these deep water oil rigs are.

From Wikipedia:
Deepwater Horizon was an ultra-deepwater, dynamically positioned, semi-submersible offshore drilling rig which sank on April 22, 2010, causing the Deepwater Horizon oil spill. The spill was the result of an explosion two days earlier in which eleven crewmen died.

Deepwater Horizon was built in 2001 in South Korea, is owned by Transocean and was leased to BP plc until September 2013. She was registered in Majuro, Marshall Islands. In September 2009, the rig drilled the deepest oil well in history at a vertical depth of 35,050. feet and measured depth of 35,055 feet.

History
Designed originally for R&B Falcon, Deepwater Horizon was built by Hyundai Heavy Industries in Ulsan, South Korea. Construction started in December 1998 and was delivered in February 2001 after the acquisition of R&B Falcon by Transocean. She was the second semi-submersible rig constructed of a class of two, although the Deepwater Nautilus, her predecessor, is not dynamically positioned.

Since arriving in the Gulf of Mexico, Deepwater Horizon was under contract to BP Exploration. Her work included wells in the Atlantis and Thunder Horse fields, a 2006 discovery in the Kaskida field, and the 2009 Tiber oilfield. On September 2, 2009, Deepwater Horizon drilled on the Tiber oilfield with a vertical depth of 35,050 feet and measured depth of 35,055 feet, of which 4,132 feet was water.

In 2002, the rig was upgraded with "e-drill," a drill monitoring system whereby technicians based in Houston, Texas, received real-time drilling data from the rig and transmitted maintenance and troubleshooting information.

At the time of the accident, Deepwater Horizon was worked on BP's Mississippi Canyon Block 252, referred to as the Macondo Prospect. The rig was last located 50 miles (80 km) off the southeast coast of Louisiana. In October 2009, BP extended the contract for Deepwater Horizon by three years, to begin in September 2010. The lease contract was worth US$544 million, a rate of $496,800 per day.

Description
Deepwater Horizon was a fifth-generation, RBS-8D design, deepwater, dynamically positioned, column-stabilized, semi-submersible drilling rig. This vessel is a Mobile Offshore Drilling Unit and can drill subsea wells for oil exploration and production purposes. The rig was 396 feet long and 256 feet wide and in 2010 was one of approximately two hundred deepwater offshore rigs that are capable of drilling in more than 5000 feet of water.

Explosion and oil spill
The rig was in the final phases of drilling a well in which casing is cemented in place, reinforcing the well. At approximately 10 p.m. CST on April 20, 2010 (0300 UTC, April 21, 2010), an explosion and fire occurred on the rig. Eleven people were missing after the incident. Seven workers were airlifted to the Naval Air Station in New Orleans and were then taken to hospital. Support ships sprayed the rig with water in an unsuccessful bid to douse the flames.

Deepwater Horizon sank on April 22, 2010, in water approximately 5,000 feet deep, and has been located resting on the seafloor approximately 1,300 feet (about a quarter of a mile) northwest of the well. The oil slick spreading from the Deepwater Horizon disaster threatens fisheries, tourism and the habitat of hundreds of bird species.