Capability and Limitation Study of the DDT Passive-active Neutron Waste Assay Device

Year
1992
Author(s)
K.L. Coop - Los Alamos National Laboratory
R.J. Estep - Los Alamos National Laboratory
N. J. Nicholas - Los Alamos National Laboratory
Abstract
The differential-dieaway-technique (DDT) passive- active neutron assay system is widely used by transuranic waste generators to certify their drummed waste for eventual shipment to the Waste Isolation Pilot Plant (WTPP). We have tested and incorporated software improvements on a mobile DDT system. The motivation for our study was the stricter criteria being established for waste emplacement at the WIPP site that have led to a renewed interest in improvements to and a better understanding of current nondestructive assay (NDA) techniques. Our study includes the effects of source position, extreme matrices, high neutron backgrounds, and source self-shielding to explore the system's capabilities and limitations and to establish a basis for comparison with other NDA systems, specifically, the Cf Shuffler developed at Los Alamos National Laboratory.