Considerations for an active and passive scanner to assay nuclear waste drums

Conference · Fri Jun 08 04:00:00 EDT 1990

OSTI ID:5856085

Martz, H E; Azevedo, S G; Roberson, G P; Schneberk, D J; Koenig, Z M; Camp, D C ^[1]

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1. Lawrence Livermore National Lab., CA (USA)

Radioactive wastes are generated at many DOE laboratories, military facilities, fuel fabrication and enrichment plants, reactors, hospitals, and university research facilities. At all of these sites, wastes must be separated, packaged, categorized, and packed into some sort of container--usually 208-L (55-gal) drums--for shipment to waste-storage sites. Prior to shipment, the containers must be labeled, assayed, and certified; the assay value determines the ultimate disposition of the waste containers. An accurate nondestructive assay (NDA) method would identify all the radioisotopes present and provide a quantitative measurement of their activity in the drum. In this way, waste containers could be routed in the most cost-effective manner and without having to reopen them. Currently, the most common gamma-ray method used to assay nuclear waste drums is segmented gamma-ray scanning (SGS) spectrometer that crudely measures only the amount of {sup 235}U or {sup 239}Pu present in the drum. This method uses a spatially-averaged, integrated, emitted gamma-ray-intensity value. The emitted intensity value is corrected by an assumed constant-attenuation value determined by a spatially-averaged, transmission (or active) measurement. Unfortunately, this typically results in an inaccurate determination of the radioactive activities within a waste drum because this measurement technique is valid only for homogeneous-attenuation or known drum matrices. However, since homogeneous-attenuation matrices are not common and may be unknown, other NDA techniques based on active and Passive CT (A PCT) are under development. The active measurement (ACT) yields a better attenuation matrix for the drum, while the passive measurement (PCT) more accurately determines the identity of the radioisotopes present and their activities. 9 refs., 2 figs.

• Research Organization: Lawrence Livermore National Lab., CA (USA)
• Sponsoring Organization: DOE; USDOE, Washington, DC (USA)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 5856085
• Report Number(s): UCRL-JC-105265; CONF-9105166--2; ON: DE91011541
• Country of Publication: United States
• Language: English

Related Subjects

052001* -- Nuclear Fuels-- Waste Processing
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
440101 -- Radiation Instrumentation-- General Detectors or Monitors & Radiometric Instruments
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
ACCURACY
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ALPHA DECAY RADIOISOTOPES
ATTENUATION
CAT SCANNING
CHEMICAL ANALYSIS
CLASSIFICATION
COMPUTERIZED TOMOGRAPHY
CONTAINERS
DIAGNOSTIC TECHNIQUES
EVEN-ODD NUCLEI
FUEL FABRICATION PLANTS
GAMMA SPECTROSCOPY
HEAVY NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
LABORATORIES
MANAGEMENT
MATERIALS
MATHEMATICAL MODELS
MEDICAL ESTABLISHMENTS
MINUTES LIVING RADIOISOTOPES
NATIONAL ORGANIZATIONS
NONDESTRUCTIVE ANALYSIS
NUCLEAR FACILITIES
NUCLEAR POWER PLANTS
NUCLEI
PACKAGING RULES
PLUTONIUM 239
PLUTONIUM ISOTOPES
POWER PLANTS
RADIOACTIVE MATERIALS
RADIOACTIVE WASTE DISPOSAL
RADIOACTIVE WASTE MANAGEMENT
RADIOACTIVE WASTES
RADIOISOTOPES
REACTORS
REGULATIONS
RESEARCH AND TEST REACTORS
RESEARCH REACTORS
SPECTROSCOPY
THERMAL POWER PLANTS
TOMOGRAPHY
TRANSPORT
URANIUM 235
URANIUM ISOTOPES
US DOE
US ORGANIZATIONS
WASTE DISPOSAL
WASTE MANAGEMENT
WASTES
YEARS LIVING RADIOISOTOPES