Science about Oil Spills

An oil spill is the accidental release of liquid petroleum into the environment. Unlike oil spills on land which can easily be contained and cleaned up, an oceanic spill poses several more ecological problems. The demand for oil worldwide, specifically in the US, requires the obtainment of this oil, whether drilled on land or pipelined up deep from the ocean floor. The oil may be a variety of different materials, including crude oil, refined petroleum oil (gasoline/diesel), oily refuse, or ship bunkers. The primary source, 70%, of accidental oil spills is associated with oil transportation by tankers and pipelines, whereas, offshore drilling contributes less than 1%. Once oil hits the water, the rapidly spreading petroleum can easily become uncontrollable. One quart of oil can contaminate one million gallons of drinking water without treatment. With the average 726 million gallons spilled annually, containing, eliminating, and un-contaminating oil spills is crucial. Such episodes have the ability to cause severe ecological risks, primarily for seabirds and mammals, resulting in substantial environmental disturbances and economic impacts on coastal activities, mainly fisheries. Oil is less dense than water, meaning the upward buoyancy force on the oil is greater than the downward force of gravity on the oil, also known as the weight of the oil. This inequality of forces causes the oil to rise in the water; however, if the oil were denser than the water, the oil would sink to the bottom. Moreover, once oil is spilled into water, due to the rapid division, the thickest the oil line gets is only fractions of a millimeter. The longer oil sits on the water, depending on the type, can lead to oil sinking to the bottom of marshes and remaining for many years. Once on the shoreline, oil turns into tar. There is suddenly no fresh drinking water and plants that once provided animals with food, are unable to produce nourishment and live. This results in the depleting of several fields, forests, and habitats. Oppositely, in the ocean the environment of all marine animals is slowly deteriorating, where the natural cycle of life is suddenly dying. The entire food chain is affected, springing conflict within all aspects of marine life.

On the other hand, there are ways to fix, contain, or lessen the damage of oil spills. The factors of the type of oil, amount, and location of the spill all play into the decision of the spill’s treatment. Preferably, if there are no serious concerns to wildlife and local environment, the choice would be to leave the oil alone, to naturally breakdown. As long as there are no immediate dangers at risk, the mixture of waves, currents, wind, sun, tide, and sand will effectively disperse and evaporate most oils. Secondly, the use of booms and skimmers contain the oil from dispersion while it is being collected. These surround and isolate the oil slick, so skimmers and absorbers can rid of the waste. Once the oil is too uncontrollable and has spread too far away from the original spill zone, dispersants are used to help chemically breakdown the oil to quicken the process of its natural biodegradation. These dispersants work by reducing surface tension that normally stops oil and water from being able to mix. This creates small droplets of oil that are easier to naturally dissolve. This, however, can cause some oil to sink to the ocean floor, where it will stay and poison the surrounding habitat. As mentioned, once oil is broken down using dispersants, oil becomes denser than water causing the oil to sink. Once all else has failed, biological agents, similar to dispersants, break up oil and allow natural processes of biodegradation occur. However, biological agents work must faster and more effective. The agent bio-chemically alters the components of the spill, allowing the breakdown of bacteria and other natural microorganisms to turn the oil into a safe and harmless substance made up of only fatty acids and CO2. The addition of phosphorus or nitrogen can speed up the process enough to be considered the most natural, yet most effective form of biodegradation.