Oil spill

An oil spill is the release of a liquid petroleum hydrocarbon into the environment, especially marine areas, due to human activity, and is a form of pollution. The term is usually applied to marine oil spills, where oil is released into the ocean or coastal waters, but spills may also occur on land. Oil spills may be due to releases of crude oil from tankers, offshore platforms, drilling rigs and wells, as well as spills of refined petroleum products (such as gasoline, diesel) and their by-products, heavier fuels used by large ships such as bunker fuel, or the spill of any oily refuse or waste oil.

Oil spills penetrate into the structure of the plumage of birds and the fur of mammals, reducing its insulating ability, and making them more vulnerable to temperature fluctuations and much less buoyant in the water. Cleanup and recovery from an oil spill is difficult and depends upon many factors, including the type of oil spilled, the temperature of the water (affecting evaporation and biodegradation), and the types of shorelines and beaches involved. Spills may take weeks, months or even years to clean up.

Deepwater Horizon oil spill

The Deepwater Horizon oil spill (also referred to as the BP oil spill, the BP oil disaster, the Gulf of Mexico oil spill, and the Macondo blowout) began on 20 April 2010 in the Gulf of Mexico on the BP-operated Macondo Prospect. Following the explosion and sinking of the Deepwater Horizon oil rig, a sea-floor oil gusher flowed for 87 days, until it was capped on 15 July 2010. Eleven people went missing and were never found and it is considered the largest accidental marine oil spill in the history of the petroleum industry, an estimated 8% to 31% larger in volume than the previously largest, the Ixtoc I oil spill. The US Government estimated the total discharge at 4.9 million barrels (210 million US gal; 780,000 m³). After several failed efforts to contain the flow, the well was declared sealed on 19 September 2010. Reports in early 2012 indicated the well site was still leaking.

Refugio oil spill

The Refugio oil spill on May 19, 2015 deposited 142,800 U.S. gallons (3,400 barrels) of crude oil onto one of the most biologically diverse coastlines of the west coast. The corroded pipeline blamed for the spill has been closed indefinitely, resulting in financial impacts to the county estimated as high as $74 million if it and a related pipeline remain out of service for three years. The cost of the cleanup was estimated by the company to be $96 million with overall expenses including expected legal claims and potential settlements to be around $257 million.

The oil spill, located immediately north of Refugio State Beach in Santa Barbara County, California, originated in a 2 feet (61 cm) diameter underground pipeline named Line 901 owned by Plains All American Pipeline. It was used to transport crude oil produced by offshore platforms from onshore receiving plants to another pipeline that transported the oil inland for processing. The oil pipeline owner initially had trouble identifying the location of the leak. The 28 year old pipeline was not equipped with an automatic shut-off valve but had to be shut down by control operators in Midland, Texas.