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| Fig. 1: An nearly-finished waste tank a the Hanford plant. (Courtesy of the DOE. Source: Wikimedia Commons) |
Whether it's nuclear energy, nuclear weapons, or any of the myriad of ways in which nuclear technology is being used today, the one commonality between them all is the production of nuclear waste. With waste comes the responsibility of dealing with it properly without damaging the environment, wildlife, or nearby populated areas. [1] During the Cold War Era, the tens of millions of dollars spent on nuclear waste research pales in comparison to the billions spent on expanding nuclear capabilities. [1] This goes to show that nuclear waste was largely an afterthought until decades later, when the assumed minor risk that is nuclear waste became a legitimate hazard that needed to be taken seriously. This paper looks to discuss a few ways to deal with different types of nuclear waste and the positives and negatives of those strategies.
Spent fuel rods were a main cause of distress for those looking to adequately deal with nuclear waste. [1] They were difficult to deal with because many facilities in the latter parts of the 20th century were running out of space in which to store them once they were used. [1] Because of limited space, a few states went as far as to pass laws that prohibited "further nuclear power plant construction" until the government developed a more feasible plan to deal with waste. [1] The spent rods were stored in enormous, reinforced concrete pools lined with welded stainless steel sheets, all housed in a building. Fig. 1 shows an example of such a tank at the Hanford, Washington site - where, infamously, caustic nuclear wastes leaked from the tanks, causing hundreds of thousands of gallons of waste fluids to pollute the underlying sediments. [2] The pool in the photo is empty, yet one might imagine that after intense use of nuclear technology, this particular storage facility would struggle to keep up and lead to problems later down the road, which is what happened.
This strategy, officially called "reprocessing," involves chemical separation of the parts that make up nuclear fuel, which can lead to their reuse, thus limiting the amount of nuclear waste that needs permanent storage. [3] This method was used during the Cold War Era, but was put on hold for decades until recently, when The Department of Energy proposed a "new generation of proliferation-resistant reactor and reprocessing technology." [4] This method is helpful in that it looks to chemically separate and recover fissionable plutonium from irradiated nuclear fuel, but is expensive and also leads to many legislative debates outside the scope of this paper.
Syroc is a type of synthetic rock that was created in the hopes of eliminating any risk of nuclear waste leaking through storage pools and into nearby water systems and polluting surrounding areas. [5] The waste is combined with a ceramic material and using the high pressure and temperature of hot-isostatic pressing, it is compressed and sealed into a ceramic wasteform. [5] Through this process, the nuclear waste is fully encapsulated in a ceramic mold that can safely store the waste for tens of thousands of years without risk of leakage--the product is then stored inside shielded containers. [5] This strategy has been popular in Australia, and in 2009, the US adopted it as the method with which they store high level waste at the Idaho National Laboratory.
© Sam Werner. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
[1] B. Hileman, "Nuclear Waste Disposal," Environ. Sci. Technol. 16, 271A (1982).
[2] H. Zhao et al., "Alteration of Kaolinite to Cancrinite and Sodalite by Simulated Hanford Tank Waste and its Impact on Cesium Retention," Clay. Clay. Miner. 52, 1 (2004).
[3] A. Andrews, "Nuclear Fuel Reprocessing: U.S. Policy Development," Congressional Research Service, RS22542, March 2008.
[4] S. Parekh, "Nuclear Waste Management," Physics 241, Stanford University, Winter 2014.
[5] "Management of Radioactive Waste in Australia," Australian Nuclear Science and Technology Organisation, January, 2011.
