Year
1988
Abstract
A new Cerenkov viewing device has been devel- oped to verify the attributes of used fuel in fuel bays illuminated by artificial lighting. Tests were carried out at the Point Lepreau Generating Station to assess the ability of the Cerenkov viewing device to verify used fuel cooled for one week and for 18 months while stored in fuel trays. The tray with fuel cooled for 18 months contained an air-filled and an unused fuel bundle, two low- burnup bundles of 1500 and 3000 MWd/t U, an empty position and 19 normal used fuel bundles with burnups ranging from 5000 to 8000 MWd/t U. The tray with fuel cooled for one week contained an air-filled bundle and 23 normal used fuel bundles. Quartz halogen, mercury vapour and fluorescent lights were used to illuminate the fuel trays. The degree of success in detecting the special bundles under the different lighting conditions is discussed. The relative Cerenkov intensities of the individual fuel bundles were calculated to enable comparison with observations made with the Cerenkov viewing device. The merits of visual and photographic observations with Cerenkov viewing devices are examined. Cerenkov spectra were taken of fuel cooled for one week at water depths of 5 and 10 metres to assess the potential effect of water absorption on the sensitivity of the viewing device in observing the Cerenkov glow emitted by used fuel.