Instrumentation and assay procedures for verification of the radionuclide content of low-level waste packages

The preferred embodiment of waste package assay instrumentation for verification of the radionuclide content is a high resolution germanium diode gamma-ray spectrometer incorporated in a segmented gamma scanner and a passive neutron interrogation system for measurement of the neutrons emitted spontaneously from a waste package. The selection criteria and rationale for this choice are discussed. Assembly and operation procedures for the instrumentation are recommended, and methods for data acquisition and reduction are given. The choice of radioisotopes for fabrication of calibration standards is /sup 60/Co at approx. 10 mCi/m/sup 3/, /sup 90/Sr at approx. 10 mCi/m/sup 3/, /sup 134/Cs at approx. 14 mCi/m/sup 3/, /sup 137/Cs at approx. 15 mCi/m/sup 3/, and transuranic alpha activity at approx. 10 nCi/g. Suggested matrix materials are given