Nuclear energy is really no safer than any other form of energy production. All of the other forms produce levels of various toxic materials during the production process. However, nuclear energy is the only form that not only produces hazardous waste during the production process but actually produces some hazard at all levels of the process, from collection to disposal. It is likely that the only safe part of the process is the administrative preparation to produce energy.
Probably the least recognized of hazards, is collection of raw material for production, which requires discovery and mining of low-grade Uranium. After ore is collected, it is milled down using a solvent, typically comprised of try-n-butyl phosphate (TBP) and di(2-ethylhexyl) phosphoric acid (D2EHPA).
These chemicals are a hazard unto themselves, prior to any energy having been created. When combined with the uranium, thorium, and radium produced during the milling process, the process of hazardous-waste building begins. This is due to tailings from the mining and milling process, which are of such a low-grade radioactivity, that the companies that process the ore are not required to clean up dust or accumulation that might develop.
Unfortunately, as has been discovered recently at sites like Lake County, Oregon, they create a continuing hazard for environment because these materials leech into the soil, ground water, or are carried by air to other environments. (EIA)
After milling, the ore undergoes an enrichment process to raise the fissionable material to usable levels. This process is expensive and for the most part is no safer than mining and milling the ore. (Enger)
After enrichment, the uranium is formed into pellets, which are encased in metal rods, and are more or less ready to produce energy. This process is also riddled with hazard, should the pellets somehow breach their containment. (USNRC)
Post-production use of the fuel has had the most obvious drawbacks, with incidents like Chernobyl in Russia, and Three Mile Island in the United States. These are not just minor drawbacks; rather, serious ecological nightmares that could change the course of an entire species, or group of species, including our own. (Enger)
The fuel only has a limited life span. Ultimately, it must be discarded in favor of new fuel rations with greater strength. However, the spent fuel cannot just be thrown away. It still maintains radioactive properties that are at levels that would pose a serious threat to any life form.
Since re-processing the spent fuel to create new fuel is complicated by a hazardous process, the only option currently available is storage. Unfortunately, since U-238 has a half-life of approximately 5 billion years, this means permanent and perpetual storage. (Enger)
When considering the additional energy expended towards labor, development of machinery and facilities, transportation, and other peripheral costs, it is hard to believe that this source of fuel is an economically viable solution. It appears that it expends more energy than it is likely to produce.
- (EIA) Energy Information Administration, US Department of Energy, Oct 8, 2005, http://www.eia.doe.gov/cneaf/nuclear/page/umtra/lakeview_title1.html (accessed 04FEB09)
- Enger, Eldon & Smith, Bradley, et al. Environmental Science: A Study of Interrelationships. 11th ed. New York: McGraw-Hill, 2006.
- (USNRC) Uranium Enrichment, United States Nuclear Regulatory Commission, January 11, 2008, http://www.nrc.gov/reading-rm/doc-collections/fact-sheets/enrichment.html (accessed 04FEB09)
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BI301: Human Ecology
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