SPENT FUEL VERIFICATION USING AN ULTRAVIOLET SENSITIVE CHARGE COUPLED DEVICE

The current generation of Cerenkov Viewing Devices (CVD) is capable of verifying most of the LWR spent fuel stored in storage ponds. However, longer-cooled fuel is accumulating in spent fuel ponds and is becoming difficult to verify. The International Atomic Energy Agency (IAEA) has requested the development of a CVD capable of verifying fuel cooled for 40 years (lifetime of a reactor) with a burnup of 10 000 MWd/t U. In addition, the IAEA has indicated a desire to store image data and to have a more objective verification of the spent fuel. A new concept imaging system, based upon a scientific charge coupled device, has been assembled to determine its ability to detect the faint Cerenkov glow emitted from LWR spent fuel. Tests were carried out in Sweden at the Ringhals Nuclear Power Plant on BWR and PWR spent fuel and non-fuel assemblies, and at the CLAB interim spent fuel storage facility. New Cerenkov characteristics, not detectable by CVDs, were observed for spent and non-fuel assemblies. Digital images are presented and the advantages of this technique for spent fuel verification (e.g., image quantitation, storage and processing) are discussed.