ICEM11 Final Program 9.7.11pm_ICEM07 Final Program ... - Events

Session 31 Abstracts
3) DISPOSITION OF TRANSURANIC RESIDUES FROM PLUTONIUM ISENTROPIC COMPRESSION
EXPERIMENT (PU-ICE) CONDUCTED AT Z MACHINE (LA-UR-10-05649) (wP-59186)
Kapil K. Goyal, Los Alamos National Laboratory; Betty J. Humphrey, Weston Solutions Inc.; Jeffry Gluth, Ktech
Corporation/Sandia National Laboratory; David M. French, Los Alamos National Laboratory (USA)
In 1992, the U.S. Congress passed legislation to discontinue above- and below-ground testing of nuclear weapons. Because
of this, the U.S. Department of Energy (DOE) must rely on laboratory experiments and computer-based calculations to verify the
reliability of the nuclear stockpile. The Sandia National Laboratories/New Mexico (SNL/NM) Z machine was developed to support
the science-based approach for mimicking nuclear explosions and stockpile stewardship. Plutonium (Pu) isotopes with greater
than ninety-eight percent enrichment were used in the experiments. In May 2006, SNL/NM received authority that the Z Machine
Isentropic Compression Experiments could commence.
Los Alamos National Laboratory (LANL) provided the plutonium targets and loaded the target assemblies provided by
SNL/NM. Three experiments were conducted from May through July 2006. The residues from each experiment, which weighed
up to 913 pounds, were metallic and were packaged into a 55-gallon drum each.
SNL/NM conducts the experiments and provides temporary storage for the drums until shipment to LANL for final waste certification
for disposal at the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico. This paper presents a comprehensive
approach for documenting generator knowledge for characterization of waste in cooperation with scientists at the two laboratories
and addresses a variety of essential topics.
4) DETECTION OF SHIELDED SEALED RADIOACTIVE SOURCES IN RADIOACTIVE
WASTE BY NON-DESTRUCTIVE ASSAY TECHNIQUES (wP-59252)
Leo P.M. Velzen, Nuclear Research and Consultancy Group;
Steven van der Marck, Nuclear Research Group (Netherlands)
Experiences dealing with the detection of a SRS or its shielding in waste by non-destructive assay (NDA) methods are seldom
reported in literature. Therefore the main objective of this paper is to assist operators of waste storage facilities or others responsible
for the radiological characterisation of waste that they are able to interpret collected radiological data on the possible presence
of a bare SRS or a shielded SRS.
This objective can be reached by simulating the gamma flux that can be measured on the surface of a waste package containing
a bare or shielded SRS. Appropriate simulations and presentations of the results will illustrate the problems that can occur by
radiological data collection and interpretation in reality.
The simulating calculations have been performed with the Monte Carlo Neutron Photon transport code (MCNP) for gamma
photons of 60Co. Obtained results e.g. gamma and total energy flux are presented in iso-plots to help non-specialist operators interpreting
own collected radiological data to recognize a SRS and dense materials in (historic) waste packages.
The MCNP simulated waste packages have been defined to reflect, as close as possible, reality, i.e. the calculated data are disturbed,
as would be the situation in the case of raw…
5) USE OF LANTHANUM BROMIDE DETECTORS TO AUGMENT
SITE SURVEYS FOR DEPLETED URANIUM (w/P-59169)
Charles Waggoner, Mississippi State University; Ronald Unz, Institute for Clean Energy Technology;
Donna Rogers, Mississippi State University; Charles R. Jones,
Jay P. McCown, Institute for Clean Energy Technology/Mississippi State University (USA)
A variety of systems have now been described for use in surveying sites for anthropogenic radiological contamination. Virtually
all of these include use of sodium iodide detectors and register detection data with global positioning satellite data. This paper
demonstrates how lanthanum bromide detectors can be used to augment existing field surveys in a manner to reduce uncertainty in
areas of low count rates and to discriminate between depleted uranium and naturally occurring uranium.
The survey system described is equipped with large (20 x 20 x 100 cm) sodium iodide (Alpha Spectra) and 7.6 x 7.6 cm lanthanum
bromide (Saint Gobain) detectors. Additional radiological detection equipment (DigiBase) was obtained from ORTEC with
survey data collected in the List Mode. Data collected in surveys were then used to generate digital maps using GeoSofts Oasis
Montaj.
Software has been developed to automatically identify areas of increased count rates using user-defined thresholds. This software
can collect the count data for the masked area and generate a composite spectrum that can be compared to a reference spectrum
believed to represent an uncontaminated area. Ratios of counts attributed to protactinium-234m (Pa-234m) are compared to
counts attributed to Bismuth-214 (Bi-214) for both the composite filed survey spectrum…
6) ULTRASONIC TECHNIQUES FOR THE IN SITU CHARACTERISATION
OF ‘LEGACY’ WASTE SLUDGES & DISPERSIONS (wP-59111)
Timothy Hunter, Jeff Peakall, Simon Biggs, Michael Fairweather, James Young, University of Leeds, Leeds (UK)
Research being undertaken at the University of Leeds, as part of the DIAMOND university consortium, is exploring the effectiveness
of various ultrasonic technologies as in situ probes to characterize and monitor nuclear waste slurries, such as the Legacy
Magnesium hydroxide sludges found in Sellafield, U.K. Through use of a commercial Acoustic Backscatter Sensor (ABS) with 1
5 MHz transducers, various properties of free-settling oxide simulant sludges were determined. Work was focused upon characterizing
essentially static sludges (to give prospective use as tools for the wastes in current deposits); although, the sensors also have
potential as dispersion monitors during any future processing and storage of the Legacy wastes, as well as many other storage, clarifier
or thickener systems across a wide range of industrial processing operations.
ABS data of mixed glass powder dispersions was analysed and compared to scattering theory, to understand the correlations
between acoustic attenuation and particulate concentration. The ABS was also calibrated to measure changes in average particulate
concentration within a settling suspension over time, and showed the depth-wise segregation of the dispersion through the settling
column at different particular time intervals. It was found that observed hindered settling also led to an increase in particulate
concentration…
94