Qualitative and quantitative measurement of radionuclides contained in drums of solid wastes

The aim of this work is to extend gamma spectrometry methods to the identification and measurement of the main radionuclides contained in drums of solid wastes. Part one deals with the general problem of variable-distance detection: - experimental evaluation of the yield curve variation for ''source-detector'' distances between 1 centimetre and 5 metres, with a trapezoidal germanium lithium junction. - Evaluation of detection limits for certain ''activation'' and ''fission products'', given the practical variation limits of the measurement parameters (distance, time). Part two gives an estimate of the geometry and position effects of point sources in a 100-litre metal drum containing absorbants of variable density (0.61 to 1.26) for distances ranging from 3 to 5 metres. Two sets of measurements were studied: - fixed positions of various ''sources'' in an immobile drum, - fixed positions of various ''sources'' in a rotating drum. By these analyses a radioactive drum measurement in non-directed geometry is possible