Certification of Plutonium Standards for KAMS Neutron Multiplicity Counter

As part of the implementation of the PEIS record of decision in January of 1997, DOE will pursue two technologies (Plutonium Stabilization Program and Mixed Pu Oxide Fuel) to disposition fifty metric tons of its stockpile of plutonium. As a result of this and in order to expedite the closure of Rocky Flats Environmental Technology Site in Colorado, DOE decided to use existing facilities at the Savannah River Site for storing all material containing plutonium at K-Area Material Storage as part of the Plutonium Stabilization Program. A neutron multiplicity counter was designed and built to carry out receipt verification measurement at the facility. Since the material covers a wide range and different levels of impurities, it is essential that we obtain a set of working standards. An agreement was drafted to select the first drums to be these standards. A plan was developed for the certification of these standards using Rocky Flat’s existing nondestructive assay equipment. This paper will discuss the types of materials to be shipped to SRS, number of standards to certify for each type of material, and the certification plan. It will also discuss the activities necessary to determine the nuclear content of these working standards to be used at SRS facilities in support of shipment and receipt of the Pu containing materials. Definition of instrument qualifications, measurement control processes, measurement methodologies, and calculations necessary to report the gram quantities and their uncertainties for plutonium, americium-241, uranium-235 (if present) and neptunium-237 (if present) will also be presented.