Oil Spills

Why in news?

• The Mauritius government declared a state of environmental emergency after a ship that ran aground in late July on a coral reef off its picturesque south-eastern coast began leaking tonnes of oil in a major ecological disaster

About Oil Spills:

• An oil spill is the release of a liquid petroleum hydrocarbon into the environment, especially the marine ecosystem, due to human activity, and is a form of pollution.
• The term is usually given 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.

Cleaning up Oil spills:

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. Methods include:

• Bioremediation: use of microorganisms or biological agents to break down or remove oil; such as Alcanivorax bacteria or Methylocella silvestris.
• Controlled burning can effectively reduce the amount of oil in water, if done properly. But it can only be done in low wind, and can cause air pollution.
• Dispersants: A dispersant is a substance that will cause the oil slick to break up and form water-soluble micelles that are rapidly diluted. The oil is then effectively spread throughout a larger volume of water than the surface from where the oil was dispersed.
• Dredging and Skimming that will physically remove the oil from the surface.
• Solidifying: Solidifiers are composed of tiny, floating, dry ice pellets, and hydrophobic polymers that both adsorb and absorb.

PRELIMS QUESTION

Which of the following methods can be used to clean up oil spills:
1.Dredging
2.Controlled burning
3.Bioremediation
Select the correct answer using the code given below:
(a)1 and 2 only
(b)2 and 3 only
(c)1 and 3 only
(d)1,2 and 3

Answer to prelims question