Wikipedia has a huge article on the Gulf oil spill

[gristy]

http://en.wikipedia.org/wiki/Deepwater_Horizon_oil_spill
135 footnote links!

This article documents a current event. Information may change rapidly as the event progresses.
Deepwater Horizon oil spill

The Deepwater Horizon oil spill (also referred to as the Gulf of Mexico oil spill, Deepwater BP oil spill, and the Macondo blowout)<3> is a massive ongoing oil spill and oil gusher in the Gulf of Mexico that started on April 20, 2010. The spill followed a blowout that caused an explosion on the Deepwater Horizon offshore drilling rig, which then sank off the coast of Louisiana. Eleven rig workers are missing and presumed dead; the explosion also injured 17 others. The oil spill covers a surface area of at least 2,500 square miles (6,500 km2) according to estimates reported on May 3, 2010 by Reuters.<4> The oil spill, originating from a deepwater oil well 5,000 feet (1,500 m) below sea level, was estimated to be discharging 5–25 thousand barrels (210,000–1,100,000 US gallons; 790,000–4,000,000 litres) of crude oil daily<5> (146–764 U.S. gallons or 550–2,890 L per minute).<6> This figure is disputed.

The spill is expected to eclipse the 1989 Exxon Valdez oil spill as the worst US oil disaster in history.<7> Experts fear that due to factors such as petroleum toxicity, it will result in an environmental disaster as the oil from the well site reaches the Gulf coast, damaging the Gulf of Mexico fishing industry, tourism industry, and habitat of hundreds of bird species.<8><9> Crews are working to block off bays and estuaries, using anchored barriers, floating booms, and sand-filled barricades along shorelines.

BP was principal developer of the Macondo Prospect oil field and leased the drilling rig from Transocean Ltd.<10> The U.S. Government has named BP as the responsible party in the incident and will hold the company accountable for all cleanup costs resulting from the oil spill.<11><12> BP has accepted responsibility for the oil spill and the cleanup costs but indicated that the accident was not their fault as the rig was run by Transocean personnel.<13> One plan, in progress, is to lower a smaller containment box hat to funnel the leaking oil, through a pipe system, up to a ship on the surface (see diagram). Initial attempts to install a larger dome resulted in failure, due to the accumulation of clathrate hydrate crystals (methane clathrate). Other plans include having the robots wrap the leaking pipes in outer casings, and shooting objects into the main leak.