Assay system to measure crate-size bulk transuranic waste

Conference · Fri Jul 01 04:00:00 EDT 1983 · Nucl. Mater. Manage.; (United States)

OSTI ID:6899589

Shunk, E R; Atencio, J D; Atwater, H F; Bernard, W; Bieri, J M; Caldwell, J T; France, S W; Hastings, R D; Herrera, G C; Kunz, W E

The Advanced Nuclear Technology Group of the Los Alamos National Laboratory recently designed and built a combined passive- and active-neutron assay system on which group members performed initial characterization measurements. The system is intended to provide sensitive assays at the 100-nCi/g level of both spontaneous fission and fissile transuranic isotopes in large crates of bulk waste. Such crates can be accommodated in the system's assay chamber whose internal dimensions are 64 by 64 by 96 in. Moderated /sup 3/He proportional counters provide a measured total 4..pi.. neutron detection efficiency of 13.5 + or - 1% for bare and moderated-fission spectrum sources placed anywhere within the volume of a standard empty crate. Initial passive neutron coincidence measurements indicate a /sup 240/Pu detection sensitivity of about 10 mg. Enhancement of the fissile-isotope assay sensitivity results from lining the assay chamber walls with a thick layer of graphite and placing specially designed prompt-fission neutron detectors within the walls. Initial pulsed-neutron measurements indicate a fissile assay sensitivity of about 30 mg of /sup 239/Pu. After completion of checkout and initial calibration measurements at Los Alamos, the assay system will be installed at a DOE facility for a 1-year test-and-evaluation program beginning in July 1983. During the period, actual transuranic waste crates averaging nearly 1000 kg each will be assayed on a routine basis.

• Research Organization: Los Alamos National Laboratory, Los Alamos, NM
• OSTI ID: 6899589
• Report Number(s): CONF-830709-
• Conference Information: Journal Name: Nucl. Mater. Manage.; (United States) Journal Volume: 12
• Country of Publication: United States
• Language: English

Related Subjects

052002* -- Nuclear Fuels-- Waste Disposal & Storage
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400101 -- Activation
Nuclear Reaction
Radiometric & Radiochemical Procedures
400104 -- Spectral Procedures-- (-1987)
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ACTIVATION ANALYSIS
ALPHA DECAY RADIOISOTOPES
ALPHA-BEARING WASTES
BARYON REACTIONS
CHEMICAL ANALYSIS
COINCIDENCE SPECTROMETRY
DECAY
DETECTION
EVALUATION
EVEN-EVEN NUCLEI
EVEN-ODD NUCLEI
FISSION
FISSIONABLE MATERIALS
HADRON REACTIONS
HE-3 COUNTERS
HEAVY NUCLEI
ISOTOPE RATIO
ISOTOPES
LASL
MATERIALS
MEASURING INSTRUMENTS
NATIONAL ORGANIZATIONS
NEUTRON DETECTION
NEUTRON DETECTORS
NEUTRON REACTIONS
NUCLEAR REACTIONS
NUCLEI
NUCLEON REACTIONS
PERFORMANCE TESTING
PLUTONIUM 239
PLUTONIUM 240
PLUTONIUM ISOTOPES
PROPORTIONAL COUNTERS
RADIATION DETECTION
RADIATION DETECTORS
RADIOACTIVE MATERIALS
RADIOACTIVE WASTES
RADIOASSAY
RADIOISOTOPES
SENSITIVITY
SPONTANEOUS FISSION
TESTING
US AEC
US DOE
US ERDA
US ORGANIZATIONS
WASTE FORMS
WASTES
YEARS LIVING RADIOISOTOPES