Aerial measurement of radioxenon concentration off the west coast of Vancouver Island following the Fukushima reactor accident

Abstract In response to the Fukushima nuclear reactoraccident, on March 20th, 2011, Natural Resources Canada conducted aerial radiation surveys over water just off the west coast of Vancouver Island. Dose–rate levels were found to be consistent with background radiation, however a clear signal due to 133 Xe was observed. Methods to extract 133 Xe count rates from the measured spectra, and to determine the corresponding 133 Xe activity concentration, were developed. The measurements indicate that 133 Xe concentrations on average lie in the range of 30–70 Bq/m 3 .