Passive neutron measurements and calculations of irradiated PWR fuel assemblies

Passive neutron measurement of spent-fuel assemblies is a convenient and rapid technique for verifying operator-declared exposure values. Experimental results have been obtained for a wide variety of pressurized-water reactor fuel assemblies at reactor and away-from-reactor storage facilities. Calculations using a single-point depletion code have been performed to evaluate and quantify the effects of various initial fuel parameters and irradiation histories on the neutron source strengths in spent-fuel assemblies.