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The Decay of Neptunium-238

Description: >A study was made of the energy levels of Pu/sup 238/ which are populated by Np/sup 238/ beta decay, by an examination of the Np/sup 238/ conversion electron spectrum in high-resolution beta spectrographs. The general features of the level scheme as previously given were unchanged but several new transitions were observed, with energies of 119.8, 871, 943, 989, and 1034 kev. Two new levels are postulated at 915 and 1034 kev which accommodate all but the 943-kev transition. A possible assignment of the 943-kev transition to the (0+.0) state of the beta vibrational band is discussed. In addition, the weak 885-kev transition from the 2+ state of the gamma -vibrational band to the 4+ state of the ground band was seen and its relative intensity determined. Comparisons were made of the experimental relative transition intensities of the three photons depopulating this band with those predicted from the rules of Alaga et al.; only fair agreement was noted. A discussion is given of the beta decay branchings and log ft values of Np/sup 238/ decay in terms of the postulated characters of the Pu/sup 238/ states and the measured spin of Np/sup 238/. (auth)
Date: December 1, 1960
Creator: Albridge, R. G. & Hollander, J. M.
Partner: UNT Libraries Government Documents Department

PNNL OS3300 Alpha/Beta Monitoring System Software and Hardware Operations Manual, Revision 0

Description: This Pacific Northwest National Laboratory (PNNL) OS3300 Alpha/Beta Monitoring System Software and Hardware Operations Manual describes how to install and operate the software and hardware on a personal computer in conjunction with the EG&G Berthold LB150D continuous air monitor. Included are operational details for the software functions, how to read and use the drop-down menus, how to understand readings and calculations, and how to access the database tables.
Date: January 25, 2006
Creator: Barnett, J. M.; Duchsherer, Cheryl J.; Sisk, Daniel R.; Carter, Gregory L.; Douglas, David D. & Carrell, Dorothy M.
Partner: UNT Libraries Government Documents Department

Calculation of Minimum-Detectable-Concentration Levels of Radioxenon Isotopes Using the PNNL ARSA System

Description: Measurement of xenon fission product isotopes is a key element in the global network being established to monitor the Comprehensive Nuclear-Test-Ban Treaty. The automated Radio-xenon Analyzer/Sampler (ARSA), built by Pacific Northwest National Laboratory, can detect 131mXe, 133mXe, 133Xe, and 135Xe via a beta-gamma counting system. Due to the variable background and sources of these four radio-xenon isotopes, it is important to have as sensitive a detection system as possible and to quantify the Minimum-Detectable-Concentrations (MDC) that such a system will be able to detect to preclude false negative and false positive results. From data obtained from IAR in Germany MDC values for 133Xe were well below the 1 mBq/SCMA as required by the PTS for the Comprehensive Test BAn Treaty [WGB TL-11,1999].
Date: March 11, 2006
Creator: McIntyre, Justin I.; Bowyer, Ted W. & Reeder, Paul L.
Partner: UNT Libraries Government Documents Department

DEPLOYING TECHNOLOGY ADVANCEMENTS FOR CHARACTERIZING THE VADOSE ZONE IN SINGLE-SHELL TANK WASTE MANAGEMENT AREAS

Description: As much as one million gallons of waste is believed to have leaked from tanks, pipelines or other equipment in the single-shell tank farm waste management areas (WMAs) within the 200 East and West areas of the U.S. Department of Energy's Hanford Site near Richland, Washington. Although some contamination has reached groundwater, most contamination still resides in the vadose zone. The magnitude ofthis problem requires new approaches for soil characterization if we are to understand the nature and extent of the contamination and take action to protect the enviromnent. Because of the complexity and expense of drilling traditional boreholes in contaminated soil, direct push characterization using a hydraulic hammer has been extensively employed. Direct push probe holes <3-inch diameter have been pushed to a maximum depth of 240 feet below ground surface in 200 East area. Previously gross gamma and moisture logging of these narrow probe holes was perfonned to identify the location of cesium-137 ({sup 137}Cs) (which has limited mobility in Hanford soil) and moisture peaks. Recently a bismuth germinate detector has been deployed for detecting and quantifying the spectrum of cobalt-60 ({sup 60}Co) (a more mobile contaminant), which provides additional information. The direct push system is configured to allow the collection ofmultiple soil core samples throughout the depth ofthe probe hole. The direct push unit has been used to place individual electrodes at a variety of depths as the probe hole is being decommissioned. These deep electrodes enable the use of soil resistivity measurement methods between surface and deep electrodes as-well-as between sets of deep electrodes. Initial testing of surface-to-deep electrode resistivity measurements in WMA C demonstrated significant improvement in defining the three dimensional extent of a contamination plume. A multiple-electrode string is presently being developed to further enhance the resolution of resistivity data. The combined use of ...
Date: January 14, 2010
Creator: SJ, EBERLEIN; HA, SYDNOR & MYERS, DA
Partner: UNT Libraries Government Documents Department

C pile slug rupture detection system

Description: This memorandum discusses experimental determination which was made of the sensitivity and operational characteristics of the modified effluent water beta activity monitor system which is to be utilized at C pile for slug rupture detection. The optimum operating conditions for this system were also determined. A comparison of the performance of the C pile system with that of the existing Hanford type beta system was made to establish the degree of improvement realized through system redesign; this information being of assistance to the Pile Physics slug rupture detector development program. This report discusses the performance of both beta sensitive systems and the parameters upon which improved performance depends. A two ionization-chamber mockup of the C pile system was installed in the near effluent water sample room at H pile and utilized in these studies.
Date: November 5, 1952
Creator: Paul, R. S.
Partner: UNT Libraries Government Documents Department

Evaluation of the Eberline TCM-2 Tool Contamination Monitor

Description: The Health Physics group at Hanford`s B Plant intends to use the Eberline Tool Contamination Monitor (model TCM-2) to survey potentially contaminated objects for unconditional release from the plant. Prior to using the TCM-2, it was evaluated to determine its capability for detecting beta/gamma-emitting contamination at or below the levels given in the Hanford Site Radiological Control Manual. The evaluation addressed how surveying irregular objects and multiple objects affects the sensitivity of the instrument. The results led to development of definitive guidelines for the placement of objects and the distance from the detector to the objects being surveyed. The evaluation determined that the TCM-2 may be used to release from radiological controls items potentially contaminated with mixed fission products if the survey meets the prescribed criteria that were derived from the evaluation process.
Date: October 1, 1993
Creator: Johnson, M. L.
Partner: UNT Libraries Government Documents Department

Radiological survey results at 4400 Piehl Road, Ottawa Lake, Michigan

Description: At the request of the US Department of Energy (DOE), a team from Oak Ridge National Laboratory conducted a radiological survey at 4400 Piehl Road in Ottawa Lake, Michigan. The survey was performed in September, 1992. The purpose of the survey was to determine if materials containing uranium from work performed under government contract at the former Baker Brothers facility in Toledo, Ohio had been transported off-site to this neighboring area. The radiological survey included surface gamma scans indoors and outdoors, alpha and beta scans inside the house and attached garage, beta-gamma scans of the hard surfaces outside, and the collection of soil, water, and dust samples for radionuclide analyses. Results of the survey demonstrated that the majority of the measurements on the property were within DOE guidelines. However, the presence of isolated spots of uranium contamination were found in two areas where materials were allegedly transported to the property from the former Baker Brothers site. Uranium uptake by persons on the property by ingestion is fairly unlikely, but inhalation is a possibility. Based on these findings, it is recommended that the residential property at 4400 Piehl Road in Ottawa Lake, Michigan be considered for inclusion under FUSRAP.
Date: April 1, 1993
Creator: Foley, R. D. & Johnson, C. A.
Partner: UNT Libraries Government Documents Department

Results of the radiological survey at the New Betatron Building, Granite City Steel facility, Granite City, Illinois (GSG002)

Description: At the request of the US Department of Energy (DOE), a team from Oak Ridge National Laboratory conducted a radiological survey at the New Betatron Building, located in the South Plant facility of Granite City Steel Division, 1417 State Street, Granite City, Illinois. The survey was performed in August 1991. The purpose of the survey was to determine whether the property was contaminated with radioactive residues, principally {sup 238}U, as a result of work done for the Atomic Energy Commission (AEC) from 1958 to 1966. The survey included a surface gamma scan of the ground surface outdoors near the building, the floor and walls in all accessible areas inside the building, and the roof; measurement of beta-gamma dose rates, alpha radiation levels, and removable alpha and beta-gamma activity levels at selected locations inside the building and on the roof; and radionuclide analysis of outdoor soil samples and indoor samples of shield-wall fill material land debris. Analysis of soil, shield-wall fill material, debris, and smear samples showed no residual {sup 238}U attributable to former AEC-supported operations at this site. None of the indoor or outdoor gamma exposure rate measurements were elevated above DOE guidelines. The slight elevations in gamma levels found outdoors and on the roof over the shield wall are typical of naturally occurring radioactive substances present in coal ash and cinders in the fill material surrounding the building and in concrete and cinders used in constuction of the shield wall. The slightly elevated gamma levels measured at soil sampling locations can be attributed to the presence of naturally occurring radionuclides. In all samples, {sup 226}Ra and {sup 238}U appeared to be in equilibrium, indicating that these radionuclides were of natural origin and not derived from former AEC activities at this site.
Date: January 1, 1992
Creator: Murray, M. E. & Uziel, M. S.
Partner: UNT Libraries Government Documents Department

LRAD, semiconductor, and other radiation detectors applied to environmental monitoring for alpha and beta contamination

Description: The very short range of alpha particles in air (typically 2 to 3 cm) has severely limited the utility of traditional alpha monitors for detecting and identifying small amounts of alpha-producing contamination in soil, water, and other materials. Monitors based on the traditional alpha detector technology are often hard-pressed to meet continually increasing sensitivity requirements. The long-range alpha detector (LRAD) avoids the distance restriction by detecting the ions produced by the interaction of alpha particles with air, rather than the alpha particles directly. The ions are swept into an ion detector either by a moving air current (generated by a fan) or a weak electric field. The LRAD is limited by the distance the ions can travel in the {approximately}5-s ion lifetime (1 to 100 m), rather than by the several-centimeter range of the alpha particles. The LRAD can be used to perform sensitive (less than 10 disintegrations per minute per 100 cm{sup 2}) field scans of large surface areas (ranging from hundreds of square meters of concrete floor to thousands of square meters of soil). Since the ``active`` element in a LRAD is a solid-metal ion collection plate, the detector is relatively inexpensive, easy to service, and quite rugged. However, the LRAD cannot supply any spectroscopic information to help identify the contaminant. Semiconductor, ionization chamber, and other types of particle detector can generate clean spectra from small samples of material and identify trace amounts of surface contamination. These detectors are rugged enough to use routinely in a mobile laboratory for isotope identification of ``hot spots`` located by the LRAD system. This detector combination has applications to field beta-particle monitoring (such as would result from tritium contamination) as well as alpha particle detection.
Date: August 1, 1993
Creator: MacArthur, D. W. & Bower, K. E.
Partner: UNT Libraries Government Documents Department

Gross Alpha/Beta Determination by Liquid Scintillation Counting

Description: Liquid scintillation counting (LSC) is used to assay liquid samples for both gross alpha and gross beta (including tritium) activity in order to declare these samples ``clean.`` This method provides several advantages over traditional gross assay techniques including easy sample preparation, no sample self-absorption, short counting times, acceptable lower limits of detection (LLD`s), and convenient sample disposal.
Date: March 1, 1992
Creator: Leyba, J. D.
Partner: UNT Libraries Government Documents Department

Optimization of detector size and scan rate for beta/gamma material release surveys

Description: DOE facilities are required to offer for sale to the public items of salvageable value when they are no longer required by the facilities. These items have to be surveyed to ensure radioactive contamination levels do not exceed the values listed in DOE Order 5400.5. Most facilities use portable contamination monitoring.equipment with probe areas between 20 and 100 cm{sup 2} to check for fixed contamination. This procedure is very labor intensive and results in survey costs that often exceed the costs recovered from selling the items. A solution would be to use large area (> 100 cm{sup 2}) detectors to find and quantify contamination. Large area scintillation detectors that can be used for beta and alpha detection simultaneously are becoming available commercially. Combining these with a rate meter that can differentiate between alpha and beta events can result in a survey that takes considerably less time to do and will save a proportional amount of money in doing so. The use and limitations of this combination of detectors and rate meters will be discussed.
Date: June 1, 1993
Creator: Bishop, R. V.
Partner: UNT Libraries Government Documents Department

Radiological survey results at 19 Wellman Street, Beverly, Massachusetts (VB024)

Description: At the request of the US Department of Energy (DOE), a team from Oak Ridge National Laboratory conducted a radiological survey at 19 Wellman Street, Beverly, Massachusetts. The survey was performed in May 1991. The Purpose of the survey was to determine if uranium work performed under government contract at the former Ventron facility had migrated off-site to neighboring areas. The survey included a surface gamma scan, a beta-gamma scan of paved areas, and the collection of soil samples for radionuclide analyses. Results of the survey demonstrated no radionuclide concentrations or radiation measurements in excess of the DOE Formerly Utilized Site Action Program guidelines.
Date: July 1, 1992
Creator: Foley, R. D. & Johnson, C. A.
Partner: UNT Libraries Government Documents Department

Data validation report for the 100-KR-4 operable unit first quarter, 1994

Description: Samples were obtained from the 100-KR-4 Operable Unit first Quarter 1994 Groundwater Sampling event. The data from the chemical analysis of fifty-eight samples from this sampling event and their related quality assurance samples were reviewed and validated to verify that reported samples results were of sufficient quality to support decisions regarding remedial actions performed at this site. Information fro the sampling event and the information validation processes are presented in this document.
Date: July 1, 1994
Creator: Krug, A. D.
Partner: UNT Libraries Government Documents Department

Real-time, in situ detection of {sup 90}Sr and {sup 238}U in soils via scintillating-fiber-sensor technology

Description: A revolutionary sensor has been developed for observing the highly energetic beta particles that originate from the decay daughters of {sup 238}U and {sup 9O}Sr. This is accomplished through (1) constructing flat ribbons that are each composed of numerous square scintillating fibers, (2) stacking these ribbons and coupling each bundled end to a photomultiplier tube, and (3) using custom-designed electronic circuitry to measure both interlayer and intralayer coincident events. By observing the relative penetration depths of incident particles, this sensor is able to discriminate between the highly energetic betas of interest and those of lower energy. After placing the sensor on the target surface and initiating data acquisition, one obtains in a few seconds to a few minutes an accurate indication of the contaminant activity per unit weight of material (in the uppermost millimeters) directly below the sensor. This combination of speed and efficiency allows rapid surface coverage in a relatively short period of time, thereby facilitating the timely removal of these contaminants. Laboratory evaluations of a prototype version of this sensor have indicated that contamination levels less than 5 pCi/g (1.8 x 10{sup 2} Bq/kg) can be determined within a few minutes.
Date: May 1, 1994
Creator: Schilk, A. J.; Knopf, M. A.; Thompson, R. C.; Hubbard, C. W.; Abel, K. H.; Edwards, D. R. et al.
Partner: UNT Libraries Government Documents Department

Radiological survey results at 30 Cliff Street, Beverly, Massachusetts (VB022)

Description: At the request of the US Department of Energy (DOE), a team from Oak Ridge National Laboratory conducted a radiological survey at 30 Cliff Street, Beverly, Massachusetts. The survey was performed in May 1991. The purpose of the survey was to determine if uranium from work performed under government contract at the former Ventron facility had migrated off-site to neighboring areas. The survey included a surface gamma scan, a beta-gamma scan of paved areas, and the collection of soil samples for radionuclide analyses. Results of the survey demonstrated no radionuclide concentrations or radiation measurements in excess of the DOE Formerly Utilized Sites Remedial Action Program guidelines. The radionuclide distributions were not significantly different from typical background levels in the Beverly, Massachusetts, area.
Date: July 1, 1992
Creator: Foley, R. D. & Johnson, C. A.
Partner: UNT Libraries Government Documents Department

Development of a scintillation flow-cell detection system for environmental restoration and waste management applications

Description: A flow-cell detection system was developed utilizing a coincidence circuit and tested with BaF{sub 2}, CaF{sub 2}:Eu and scintillating glass. The coincidence detection system reduced the background from {approximately}200 cps to {approximately}0.5 cps. The detection efficiencies for these cells ranged from 0.38 to 0.66 for {sup 45}Ca beta particles (E{sub max} = 0.257 MeV) and from 0.45 to 0.52 for {sup 233}U alpha particles (E{sub {alpha}} = 4.8 MeV). The minimum detectable activity was calculated for a 30 s count time and determined to be in the range of 1-2 Bq.
Date: May 1, 1996
Creator: DeVol, T.A.; Branton, S.D. & Fjeld, R.A.
Partner: UNT Libraries Government Documents Department

MCNP Analysis of a Phoswich Detector

Description: A series of triple crystal phosphor sandwich detectors have been developed and constructed for testing at the University of Missouri-Columbia [1-7]. These detectors can simultaneously measure alpha, beta, and gamma radiation and utilize digital pulse shape discrimination to identify and separate radiation events coming from each of the separate phosphors. The research reported here uses Monte Carlo [8] software analysis to determine operating parameters for this detector system and optimizes its design for measuring trace amounts of alpha, beta and gamma-ray activity in effluent streams from nuclear waste cleanup processes. The previously designed, fabricated and tested phoswich detector [5] consisted of three scintillators placed on top of each other with a common diameter of 5.08 cm and viewed with a single photomultiplier tube. The scintillators (ZnS-0.00376 cm, CaF{sub 2}-0.254 cm and NaI-2.54 cm) interact preferentially with alpha, beta and gamma-ray radiation, respectively. This design allows preferential, but not exclusive, interaction of various radiations with specific layers. Taking into account and correcting for events that can occur in the ''wrong'' phosphor, this system was experimentally shown to have a 99% accuracy for properly identifying radiation coming from a mixed alpha/beta/gamma-ray source. In an attempt to better understand this system and provide design guidance for a detector system to be used in monitoring effluents from nuclear waste treatment facilities, this detector was modeled using MCNP [8]. This analysis [9] indicated that the thin ZnS layer adequately stops alpha particle energy, but greatly reduces beta detection efficiency to essentially zero at beta E{sub max} energies below 300 keV. The CaF{sub 2} layer, designed to keep any beta particle energy from entering the NaI detector results in an incorrect gamma-ray response that is approximately 23% of the NaI's response and is variable with energy. High energy beta events in the CaF{sub 2} can lead ...
Date: June 12, 2002
Creator: Childress, Nathan & Miller, William H.
Partner: UNT Libraries Government Documents Department