Tertiary
Methyl Tertiary Butyl Ether, also know as MTBE, is in a group of gas additives called "oxygenates" because they increase the oxygen level in gasoline. The use of oxygenates has increased significantly since Clean Air Act was signed in 1990. The two-part act mandated the use of cleaner burning gasoline in metropolitan areas throughout the United States as stated by Nichols et al. The most significant part of this act was the reformulated gasoline (RFG) program that took affect in 1995, calling for reformulated gasoline in cities with the worst ground-level ozone (smog). RFG is oxygenated gasoline (minimum of 2 percent oxygen by weight) that is specially blended to have fewer polluting compounds than conventional gasoline (EPA 2000). Not only did the cities and areas that fit the requirements of this act start to use RFG, so did many other states. This, in turn, increased the use of oxygenates, especially MTBE. MTBE was chosen over other oxygenates because of many economic reasons. MTBE has very favorable blending characteristics making it easy to produce, it has a low volatility that make it easier to meet emission standards, and it can be shipped through existing pipelines.
concerns have been raised about its role in contamination of soil and ground water supplies. Many studies have been finding MTBE in ground water nationwide. MTBE is released into the soil primarily from petroleum leaking from underground storage tanks. Other sources include leaking from above ground tanks, fuel pipelines, refueling stations, and accidental spills (CRS 2000). Since these studies have come out the EPA has begun a process to decrease the use of MTBE and finding alternatives to MTBE such as other more manageable oxygenates like ethanol. But that does not get MTBE out of the nation's water supply. Now with the threat of MTBE in our water known the EPA has done some rethinking. They are trying to find ways to either eliminate MTBE or use it in safe amounts. A main idea is alternatives to MTBE, such as Ethanol. Although much uprising will come and has come from the increase in gas price because of this, it will be safer oil. But what is safer oil? How many more hints are we going to need that it is time to move on to other alternatives then fossil fuels? Another method is Air Sparging, an in situ method where air is injected straight into the infected area to volatilize the contaminates. This method also has set backs. It is only effective in homogeneous soil because heterogeneous soil may cause dispersion of the contaminates and channeling of the air flow. Also again the characteristics of MTBE make is so a much greater amount of air is needed to volatilize MTBE. As mentioned before, MTBE has different characteristics then other oxygenates. So other treatment methods not thought to helpful with petroleum spills could be helpful for the distinctive MTBE. One such treatment is the "Pump and Treat" method, which is ex situ. Since MTBE moves fast through the soil, groundwater can be pumped out and treated outside of the soil. A few problems exist in this case. One being that if the MTBE reaches a micropore that is not effected by groundwater, it can slowly diffuse into the groundwater. Aquifers with high total porosity but
Some common words found in the essay are:
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Approximate Word count = 1396
Approximate Pages = 6 (250 words per page double spaced)
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