MOBILE INSTRUMENTATION FOR NUCLEAR MATERIAL CHARACTERIZATION

ABSTRACT

Nuclear material consolidation and conversion of HEU to LEU is an essential element of the decommissioning process in Russia. Among other things, it is important to assure the receiver facility that the material it receives meets the acceptance criteria for proper operation of the re-packaging and down blending process. It is equally important for the shipper facility to check the shipments against the same criteria to be assured of acceptance at the receiver facility. Such measurements, however, present significant procedural challenges arising from calibration, operation, and sensitivity variations between different chemical and physical forms of the material. The most practical method to overcome these difficulties is to deploy a self-contained instrument van that is transported with the material shipment and is used to make the assays at the shipper site or, if required, at both the shipper and receiver sites. The measurement process as described also provides for detection of diversion. The same measurements can also ensure that the input material to the down blending operation meets the MPC&A contract terms and programmatic transparency objectives regarding the “attractiveness” of the HEU feed material. These terms make it essential that the material be measured for both total uranium concentration and for its U-235 enrichment.

This paper will describe the instrumentation required to meet the criteria described above and how they were installed into a transportable ISO container that was shipped to Russia at the beginning of this year. 

INTRODUCTION

Since 1994, the Department of Energy has undertaken the mission of upgrading the safeguards and security of Russian nuclear facilities under the Material Protection, Control and Accounting (MPC&A) program.

In early 1999, the MPC&A program launched the Material Conversion and Consolidation (MCC) Project initiative with Russia. The mission of the MCC Project was to assist in consolidating special nuclear material (SNM) to fewer locations, and to down blend the material with natural or depleted uranium to reduce its attractiveness as a diversion target. The scope of these activities was to include Minatom facilities, and discussions and negotiations to solidify the processes and procedures were undertaken.