People put things into storage for many reasons, usually it’s things we might want to see again or else why are we keeping it? Nuclear waste is not one of those things. It’s something we hope to never see again when we lock it away. For this reason very complicated steps are involved in the long term storage of such wastes. In most instances the intention is that these items will remain safely locked away for thousands of years.
On a small scale getting rid of something forever can be fairly simple. Just drop it into an icy crevice or a trench deep in the ocean. Many a treasure has been lost buried in unmarked holes or sealed deep in caves long forgotten and never to be seen again. Unfortunately for scientists the dangers presented simply by the presence of nuclear waste in open air or water or even buried securely far from human habitation are too great to be handled without the utmost caution. Nuclear waste presents an unprecedented scientific dilemma, since this radioactive material can remain dangerous long, long into the future, beyond perhaps even this era into a time when records may have been lost and warnings and locations of dangerous materials lost to the ravages of time.
The first approach scientists take in ensuring the highest security in radioactive waste storage is the careful design of incredibly long-lasting storage containers that sealed the material against even the most destructive of accidents. These storage containers or “casks” are made from the most sturdy of metals. Externally they are designed to withstand the most brutal punishment and tested to this effect. Even the earliest and most crude designs for containers built for the storage and transport of radioactive materials proved hardy enough to withstand the impact of a speeding diesel locomotive and still remain tightly sealed. This was 20 years ago and the technology has only improved.
Modern casks have multiple layers of protection for the dangerous material kept inside. Usually multiple layers of high-impact steel are separated by layers of concrete inches thick. The construction of the cask is usually so highly protective of its dangerous contents that be container itself is 5 to 10 times larger than the innermost storage compartment.
Safety is augmented by the suspension of radioactive material in glass. Wastes are mixed with molten glass before being form poured into the innermost storage container of the multi ton cask. This ensures that even if the cask itself cracked open in the most unlikely circumstances the dangerous radioactive material would still be stored in a solid form, unable to flow out of the broken cask.
Unfortunately public opinion is currently extremely negative on the issue of transporting radioactive material across borders for long-term secure storage. As a result the expense of casking radioactive waste is often not undertaken as temporary storage while less secure requires less space and expense. People do not realize in large numbers how much safer the transportation of radioactive waste is then to simply leave it in temporary storage at the location where it is generated. Eventually however the need to store permanently and therefore transport safely radioactive waste material will become undeniable – fortunately the tools to do so are readily at hand.