(BBC News: February 14, 2016)
Nuclear energy has been praised as an alternative energy source because of its relatively low carbon footprint. However, a debated issue with nuclear energy is what to do with the radioactive waste that is left over. Leaking of radioactive waste could cause serious problems to the surrounding environment and human health. Scientists and governments have been looking for solutions to this storage problem. This week a huge step has been made in finding an effective way to manage this waste.
UK scientists from Scheffield University have produced a new mix of cement that is much more effective at storing nuclear waste in deep repository than what is currently available. Producing this mix was possible using a new lab that has a synchroton, which shoots x-rays into cement samples to analyze their structure on a microscopic scale. The team has been conducting a long-term study over the past 18 months and has now produced a cement that will be able to store nuclear waste effectively for 2,000 years. This is a 50% improvement than the current proposed barrier solution named Nirex Reference Vault Backfill. This new mixture has been named No. 7, and contains blast furnace slag. The blast furnace slag introduces sulphides that react with water to produce sulphate mineral phases that readily trap radio isotopes that try to permeate through it. Even with these improvements, his new finding is not a stopping point for the research team. They are continuing to look at more mixes to investigate even more effective solutions. Once a week a new sample of a mix is subjected to the synchroton and they collect the resulting data. They predict this investigation could go on for two years.
This research was discussed at the annual meeting of the American Association for Advancement of Sciene (AAAS), and is a focus globally in finding effective alternate energy sources.