Activation of gold by the neutrons from the JCO accident

Gold-198 induced by the JCO criticality accident of 30 September 1999 was measured to evaluate the environmental impact of the neutrons derived from the accident. The number of 198Au atoms at about 370 m from the JCO site was estimated to be as high as 6×106 atoms g−1. The influence of the accident was observed up to 1400 m. The general trend of the neutron fluence as a function of distance from the site was well reproduced by theoretical calculations.