There are 16 nuclear reactors at nine power stations across the UK, and over 430 around the world. Making them safe as they come to the end of their lives is a big challenge; the distribution of radioactive by-products of nuclear fission (the process used to split atoms to generate energy) needs to be carefully assessed before deciding how to minimise and safely store the waste. Scientists at the University of Southampton’s Geosciences Advisory Unit (GAU), led by geochemist Professor Ian Croudace and radiochemist Dr Phil Warwick, have developed a better and faster way to extract and measure volatile radioactive materials, specifically tritium and carbon-14 (C-14), which contaminate parts of nuclear sites. The information they have gained has helped sites that are decommissioning nuclear
power stations to make appropriate decisions on the proper disposal of the radioactive waste materials. Volatile materials Over the past 10 years, Ian’s team at the GAU, an industry-focused consultancy unit within the University, has been investigating how to extract the radioactive isotopes tritium and carbon-14 from nuclear site materials. These isotopes are unusual in that they are frequently volatile, which enables them to spread throughout reactor buildings and get into the wood, concrete and metalwork. Tritium, an isotope of hydrogen, is classed as a ‘soft beta emitter,’ meaning that its external radiation risk is low. However, Ian explains that because tritium is generally volatile, it can be inhaled and lead to an internal }
Techniques developed by the University’s Geosciences Advisory Unit are enabling nuclear power stations in the UK (like Chapelcross, shown here) and across the world to be made safe more quickly and cost-effectively than was previously possible Image courtesy of Magnox Ltd Ocean and Earth Science New Boundaries | University of Southampton
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