The Tohoku earthquake and tsunami of 2011 resulted in a major nuclear accident at the Fukushima Daiichi Nuclear Power Plant. Radioactive releases occurred to the atmosphere and contamination was found in land within and beyond the exclusion zone set up around the site.
In the aftermath, the Japan Atomic Energy Agency (JAEA) advised on accident recovery actions, including remediation options for contaminated locations. Quintessa provided support to JAEA by developing an assessment model for land contaminated with Cs-137. The model represents different types of land use consistent with the region (e.g. farming, forest and residential land) and can be used to estimate potential radiation doses with and without various remediation methods. It enables a range of remediation options to be assessed for individual sites, based on measured levels of contamination, its distribution and patterns of land-use.