Nancy Van Prooyen looks at some of the new technology that is being used to clean up the BP oil spill.
|A worker cleans up oily waste on Elmer’s Island, just west of Grand Isle, La., in May. Photo credit: U.S. Coast Guard Petty Officer 3rd Class Patrick Kelley.
On April 20, an explosion in the Gulf of Mexico, off the coast of Louisiana, rocked the Deepwater Horizon oil rig. Colossal environmental damage caused by the oil spill has continued since this incident dominated headlines around the world. British Petroleum, the oil giant that operated the rig, has come under relentless public pressure and mounting criticism for its ineffectual handling of this ecological tragedy. Even now, hundreds of thousands of barrels of oil are spilling into the ocean each day and are carried inward by currents to delicate marshes and wetlands. The coastal wetlands already suffer from overpopulation, pollution and lingering effects from Hurricane Katrina. It will take years for us to realize the true impact of the spill on the surrounding ecosystems.
Unfortunately, the United States coastline is no stranger to catastrophic oil spills. Although the BP spill is now the largest ever, the previous holder of this dubious distinction was the Exxon-Valdez spill of 1989. Currently, BP is implementing crude and outdated methods inherited from past spills for the offshore cleanup.
There are three conventional methods that are used widely to collect or clean up oil from water:
1. Water-oil separation: BP has employed hundreds of vessels, including some of the largest skimmers in the world, to skim the surface of the water and manually collect floating oil. Although this method works well in calm, isolated water, strong ocean currents largely render it ineffective. BP also uses centrifuges to separate oil from the gathered seawater. However, these centrifuges have varying efficiency in removing the oil, making this a rather costly procedure in terms of time, effort and money.
2. Controlled burns: In a more extreme attempt to remove the oil, BP is burning large areas of oil on the sea surface. This releases greenhouse gases such as sulfur dioxide, nitrous oxides and methane into the air. The thick black clouds are then carried into the lungs of workers and residents in the coastal communities. People with asthma or serious heart problems are particularly susceptible to the toxic burn-off. Tragically, large numbers of marine wildlife that live near the water surface often are corralled into the areas demarcated for combustion, and are, quite literally, burned alive.
3. Chemical dispersants: The third main method BP is using to clean up oil involves sprinkling large amounts of chemical dispersants by boat, aircraft and workers on the shore. Dispersants cause the oil to break up into smaller droplets, which become miscible in water. However, these dispersants may result in more ecological harm than good. The chemicals contain nonbiodegradable toxins that can kill fish and migrate great distances. Dispersants also are blamed for the massive oil plumes several hundreds of feet underwater, harmful to all aquatic life, especially fish larvae and filter feeders. Moreover, because of the large volume of oil that has been spilled, the amount of dispersant required and the amount of oil dispersed simply suppresses the problem, rather than solving it.