by Katherine Berezowskyj
After a nuclear reactor has produced base-load, CO2-free energy, there is the matter of what to do with the left-over nuclear fuel. There are currently two options for dealing with the spent or “used” fuel. First is the direct disposal in a deep geological repository. The other option, not currently used in the U.S., is to recycle the spent nuclear fuel.
Yes, it is possible to employ the same approach used to reduce the waste of aluminum cans and paper for used nuclear fuel. And just as the recycling process keeps these materials from being thrown away in a landfill, the same is possible for recycling spent nuclear fuel. Recycling allows for approximately 96% of the spent fuel to be recovered and reused as new fuel in a reactor, thereby reducing the need for new uranium fuel by 25%.
The question then becomes, does recycling generate significantly larger quantities of waste than directly disposing of the spent fuel? The answer is yes and no because it depends on the kinds of waste, whether Low or High Level Waste. The spent fuel generated after time in the reactor is highly radioactive and is considered High Level Waste (HLW). After recycling, only a small portion, 4%, contained in the nuclear spent fuel, is not recyclable. This small portion is made into a very stable glass waste form and is classified as HLW. The metal parts of the nuclear spent fuel assembly are handled similar to HLW. Low Level Waste (LLW) on the other hand, is not highly radioactive and is produced from activities during the recycling process such as gloves, tools, and protection clothes that are used to facilitate the process.
When comparing the volume of waste changes during recycling, the volume of LLW generated is equivalent to about 2% of current LLW production in the U.S. But the LLW produced does not have the same levels of radioactivity as HLW and is able to be stored in a surface or near-surface facility. HLW is much more complicated and expensive to dispose of because it is requires burial in a repository deep underground.
As far as numbers go, recycling reduces the volume of HLW by a factor of 4-5 when compared to direct disposal of HLW. Looking at the spent fuel that comes from U.S. reactors each year, it would cut the quantity of HLW from approximately 2,000 metric tons to around only 780 cubic yards. Reducing the quantity of HLW by such a large degree can significantly delay the need to build an additional repository to hold the HLW produced in the U.S. This has the potential for a very considerable positive economic impact. Also, the recycling process significantly diminishes the waste toxicity by a factor of 10.
When it is possible to reduce the volume of HLW and drastically cut the need for complicated underground storage, why take care of it any other way?
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