Thursday, September 13, 2012

6 Things to do with Nuclear Waste: None of them Ideal

High-level radioactive or nuclear waste is “spent” uranium fuel used in nuclear reactors. This spent fuel is thermally hot and highly radioactive, usually in the form of uranium 235 contained in ceramic pellets inside metal rods. What do we do with this spent fuel? Right now, nothing really, presumably we are waiting for a future generation to figure out where to safely store it all. It will only be rendered harmless through a process of decay that can take thousands of years. The US, which had over 72,000 tons of nuclear waste as of 2011, has no long-term facility for storing high-level nuclear waste. The interim answer is either to store this spent fuel in water-cooled pools on the site of the reactor, or to transfer it temporarily to dry casks. With the exception of the expensive endeavor of reprocessing this spent fuel to extract plutonium for commercial use, there is no known alternative to burying nuclear waste in massive underground facilities, which currently do not exist. Throwing it in the Ocean is clearly not recommended, though that hasn’t stopped governments in the past. Here’s what we’re doing with it now:    

Temporary Spent Fuel Pools

Much of the US’ nuclear waste is being stored in large water-cooled pools onsite at nuclear power plants. This is not the safest method: The release of radiation at Japan’s Fukushima plant came from fuel stored in pools. This poses a particular problem for the state of Minnesota, where nuclear power plants were not designed to take on nuclear waste storage. Designers were banking on the construction of a large long-term nuclear waste storage facility at Yucca Mountain, Nevada, which never materialized due to fears of ground-water contamination.

Temporary Dry Cask Storage

In some cases, after waste is cooled in spent fuel pools it is transferred and sealed dry casks, which are steel and concrete containers. The problem is that dry-casking is much more expensive than pool storage, but it is also much safer. Dry casks are much less vulnerable to fire, flooding, earthquakes or other machinations of Mother Nature. Scientists say they have never leaked radiation.

Read more: http://oilprice.com/Alternative-Energy/Nuclear-Power/6-Things-to-do-with-Nuclear-Waste-None-of-them-Ideal.html

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