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Core flow experiment protocol

Description: This letter report describes the current status of the core flow through apparatus and describes the protocol and test matrix to be followed during the initial experimental stage of radionuclide transport studies in the Integrated Testing task.
Date: December 1, 1997
Creator: Viani, B.E. & Martin, S.I.
Partner: UNT Libraries Government Documents Department

Rapid diffusion method for physicochemical characterization of metal ligands in soils and sediments

Description: A diffusion method is described that allows preliminary characterization of metals in soils and sediments while minimizing the potential for alteration of metal form. In addition, examples of the application of the method to model compounds of Pu in the soil are given. (ERB)
Date: January 1, 1975
Creator: Garland, T.R.; Wildung, R.E. & Pelroy, R.A.
Partner: UNT Libraries Government Documents Department

Mathematical model for the transport of environmental plutonium

Description: From joint meeting of the American Nuclear Society and the Atomic Industrial Forum and Nuclear Energy Exhibition; San Francisco, California, USA (11 Nov 1973). A mathematical model describing the behavior of particulate Pu in the lower atmosphere is proposed which accounts for particles settling or impinging on the earth's surface as well as particle re-entrainment or resuspension. The assumptions used and system of equations derived are discussed. (LCL)
Date: April 30, 1974
Creator: Travis, J.R.
Partner: UNT Libraries Government Documents Department

One-dimensional model of the movement of trace radioactive solute through soil columns: the PERCOL model

Description: A one-dimensional mathematical model, PERCOL, has been developed to predict the movement of radionuclides through porous media as a function of measurable chemical parameters of the media. Laboratory column studies were conducted to verify the model. System parameters considered include soil type, radionuclide type, waste composition, flow rate, column length, and soil saturation. The agreement between measured radionuclide movement and that predicted by the model is considered good.(auth)
Date: January 1, 1972
Creator: Routson, R.C. & Serne, R.J.
Partner: UNT Libraries Government Documents Department

OPTIMIZING RADIOLOGICAL MONITOR SITING OVER THE CONTINENTAL U.S.

Description: The US Environmental Protection Agency (EPA) is installing a network of sensors in the US to monitor background radiation and elevated radiation levels expected from a possible nuclear incident. The network (RadNet) of 180 fixed sensors is intended to provide a basic estimate of the radiation level throughout the US and enhanced accuracy near population centers. This report discusses one of the objective methods for locating these monitors based on criteria outlined by the EPA. The analysis employs a representative climatology of incident scenarios that includes 50 release locations, four seasons and four times of the day. This climatology was calculated from 5,600 simulations generated with NOAA-ARL's HYSPLIT Lagrangian trajectory model. The method treats the release plumes as targets and monitors are located to maximize the number of plumes detected with the network. Weighting schemes based on detection only, dose-weighted detection and population-dose weighted detection were evaluated. The result shows that most of the monitors are located around the population centers, as expected. However, there are monitors quite uniformly distributed around the less populated areas. The monitors at the populated areas will provide early warning to protect the general public, and the monitors spread across the country will provide valuable data for modelers to estimate the extent and the transport of the radioactive contamination.
Date: October 29, 2007
Creator: Chen, K; Robert Buckley, R; Robert Kurzeja, R; Lance Osteen, L & Saleem Salaymeh, S
Partner: UNT Libraries Government Documents Department

Phase I Transport Model of Corrective Action Units 101 and 102: Central and Western Pahute Mesa, Nevada Test Site, Nye County, Nevada with Errata Sheet 1, 2, 3, Revision 1

Description: As prescribed in the Pahute Mesa Corrective Action Investigation Plan (CAIP) (DOE/NV, 1999) and Appendix VI of the Federal Facility Agreement and Consent Order (FFACO) (1996, as amended February 2008), the ultimate goal of transport analysis is to develop stochastic predictions of a contaminant boundary at a specified level of uncertainty. However, because of the significant uncertainty of the model results, the primary goal of this report was modified through mutual agreement between the DOE and the State of Nevada to assess the primary model components that contribute to this uncertainty and to postpone defining the contaminant boundary until additional model refinement is completed. Therefore, the role of this analysis has been to understand the behavior of radionuclide migration in the Pahute Mesa (PM) Corrective Action Unit (CAU) model and to define, both qualitatively and quantitatively, the sensitivity of such behavior to (flow) model conceptualization and (flow and transport) parameterization.
Date: February 1, 2009
Creator: Ruskauff, Greg
Partner: UNT Libraries Government Documents Department

Stabilization of Plutonium in Subsurface Environments via Microbial Reduction and Biofilm Formation

Description: Plutonium has a long half-life (2.4 x 104 years) and is of concern because of its chemical and radiological toxicity, high-energy alpha radioactive decay. A full understanding of its speciation and interactions with environmental processes is required in order to predict, contain, or remediate contaminated sites. Under aerobic conditions Pu is sparingly soluble, existing primarily in its tetravalent oxidation state. To the extent that pentavalent and hexavalent complexes and small colloidal species form they will increase the solubility and resultant mobility from contamination sources. There is evidence that in both marine environments and brines substantial fractions of the plutonium in solution is present as hexavalent plutonyl, PuO2 2+.
Date: April 19, 2007
Creator: Boukhalfa, Hakim; Icopini, Gary A.; Reilly, Sean D. & Neu, Mary P.
Partner: UNT Libraries Government Documents Department

Surveillance of site A and plot M, report for 2007.

Description: The results of the environmental surveillance program conducted at Site A/Plot M in the Palos Forest Preserve area for Calendar Year 2007 are presented. Based on the results of the 1976-1978 radiological characterization of the site, a determination was made that a surveillance program be established. The characterization study determined that very low levels of hydrogen-3 (as tritiated water) had migrated from the burial ground and were present in two nearby hand pumped picnic wells. The current surveillance program began in 1980 and consists of sample collection and analysis of surface and subsurface water. The results of the analyses are used to: (1) monitor the migration pathway of water from the burial ground (Plot M) to the hand-pumped picnic wells, (2) establish if other buried radionuclides have migrated, and (3) monitor the presence of radioactive materials in the environment of the area. Hydrogen-3 in the Red Gate Woods picnic wells was still detected this year, but the average and maximum concentrations were significantly less than found earlier. Hydrogen-3 continues to be detected in a number of wells, boreholes, dolomite holes, and a surface stream. Analyses since 1984 have indicated the presence of low levels of strontium-90 in water from a number of boreholes next to Plot M. The results of the surveillance program continue to indicate that the radioactivity remaining at Site A/Plot M does not endanger the health or safety of the public visiting the site, using the picnic area, or living in the vicinity.
Date: March 25, 2008
Creator: Golchert, N. W. & Oversight, ESH /QA
Partner: UNT Libraries Government Documents Department

High resolution gamma spectroscopy well logging system

Description: A Gamma Spectroscopy Logging System (GSLS) has been developed to study sub-surface radionuclide contamination. The absolute counting efficiencies of the GSLS detectors were determined using cylindrical reference sources. More complex borehole geometries were modeled using commercially available shielding software and correction factors were developed based on relative gamma-ray fluence rates. Examination of varying porosity and moisture content showed that as porosity increases, and as the formation saturation ratio decreases, relative gamma-ray fluence rates increase linearly for all energies. Correction factors for iron and water cylindrical shields were found to agree well with correction factors determined during previous studies allowing for the development of correction factors for type-304 stainless steel and low-carbon steel casings. Regression analyses of correction factor data produced equations for determining correction factors applicable to spectral gamma-ray well logs acquired under non-standard borehole conditions.
Date: May 1, 1997
Creator: Giles, J.R. & Dooley, K.J.
Partner: UNT Libraries Government Documents Department

Atmospheric Transport of Radionuclides

Description: The purpose of atmospheric transport and diffusion calculations is to provide estimates of concentration and surface deposition from routine and accidental releases of pollutants to the atmosphere. This paper discusses this topic.
Date: March 3, 2003
Creator: Crawford, T.V.
Partner: UNT Libraries Government Documents Department

Intracrystalline diffusion in clinoptilolite: Implications for radionuclide isolation

Description: Experiments have been performed to measure the rate of exchange diffusion in the zeolite clinoptilolite (CL) for elements important to radionuclide isolation at Yucca Mountain, NV. Clinoptilolite is one of the major sorptive minerals in the tuffs at Yucca Mountain, and occurs both as a major component in zeolitized units (Calico Hills), and in fractures in non-zeolitized tuffs (Topopah Spring). Field evidence and numerical modeling suggests that the movement of fluids through the tuff rocks adjacent to the potential repository may occur via episodic flow through fractures. Under conditions of rapid fracture flow the effective sorptive capacity of fracture-lining clinoptilolite may be controlled by exchange diffusion rather than exchange equilibrium.
Date: November 16, 1995
Creator: Roberts, S.K.; Viani, B.E. & Phinney, D.
Partner: UNT Libraries Government Documents Department

Old F-Area Seepage Basin Transport Analyses in Support of a SCDHEC Mixing Zone Application

Description: This report documents the groundwater flow and transport results presented in the groundwater mixing zone application (GWMZ) for the Old F-Area Seepage Basin (OFASB) submitted to the South Carolina Department of Health and Environmental Control (SCDHEC) in March, 1997 (WSRC, 1997).
Date: December 4, 1998
Creator: Aleman, S.E.
Partner: UNT Libraries Government Documents Department

Recent drilling program to investigate radionuclide migration at the Nevada Test Site

Description: Recent drilling affords new opportunities to investigate the occurrence, distribution and transport of radionuclides in the unsaturated and saturated zone at the Nevada Test Site (NTS), Nye County, Nevada. This program is unique becmise of the elevated activities of radionuclides encountered during drilling (> 3.7E+6 Bq/L 3H), extreme completion depths (> 950 m), the expense of constructing new wells (> $IE+6/borehole), and collaboration of government, academic, and industrial partners in the planning and execution of the program. The recent chilling is significant because it substantively augments earlier field of radionuclide migration at NTS, most notably the 1974 CAMBRIC RNM experiment Sites of five nuclear tests fired below or adjacent to the saturated zone have been drilled. Three of the events were fired in Yucca Flat which is a hydrologically closed basin and two were fired in fractured volcanics of Pahute Mesa. Results from Yucca Flat indicate that volatile and refractory radionuclides, fractionated at zero time, we not highly mobile under sawmted conditions. In contrast, borcholes completed on Pahute Mesa indicate Wgh concentrations of tritium (> 3.7E+6 Bq/L 3H) and other radionuclides may be rted more than 300 m from event cavities as dissolved species or as colloids.
Date: April 1, 1997
Creator: Smith, D. K.
Partner: UNT Libraries Government Documents Department

Corrective action unit modeling approach for the underground test area, Nevada Test Site, Nye County, Nevada

Description: The modeling approach serves as a template for the development, application, and interpretation of the Corrective Action Unit (CAU) - scale saturated groundwater flow and transport model (herein called the CAU model) to be used for forecasting radionuclide migration in all Nevada Test Site (NTS) CAUs, consistent with the Federal Facility Agreement and Consent Order (FFACO) and Underground Test Area (UGTA) strategy. A summary of the project background, the FFACO and strategy, and the roles of participating agencies, is provided followed by a description of the contents of the document.
Date: March 1, 1998
Partner: UNT Libraries Government Documents Department

Laboratory evaluation of colloidal actinide transport at the Waste Isolation Pilot Plant (WIPP): 1. crushed-dolomite column flow...

Description: Colloid-facilitated transport of Pu, Am, U, Th, and Np has been recognized as a potentially important phenomenon affecting the performance of the Waste Isolation Pilot Plant (WIPP) facility being developed for safe disposal of transuranic radioactive waste. In a human intrusion scenario, actinide-bearing colloidal particles may be released from the repository and be transported by brines (approximately 0.8 to 3 molal ionic strength) through the Culebra, a thin fractured microcrystalline (mean grain size 2 micrometers) dolomite aquifer overlying the repository. Transport experiments were conducted using sieved, uniformly packed crushed Culebra rock or nonporous dolomite cleavage rhombohedra. Experiments with mineral fragments and fixed and live WIPP-relevant bacteria cultures showed significant levels of retardation due to physical filtration effects. Humic substances were not attenuated by the Culebra dolomite. Comparison of elution curves of latex microspheres in columns prepared with microcrystalline rock and nonporous rock showed minimal effect of Culebra micropores on colloid transport. These data form part of the basis to parameterize numerical codes being used to evaluate the performance of the WIPP.
Date: December 31, 1996
Creator: Yelton, W.G.; Behl, Y.K.; Kelly, J.W.; Dunn, M.; Gillow, J.B.; Francis, A.J. et al.
Partner: UNT Libraries Government Documents Department

Environmental monitoring of Columbia River sediments: Grain-size distribution and contaminant association

Description: Based on the results of this study and literature review, the following conclusions can be made: Sediment grain size and TOC (total organic carbon) influence contaminant fate and transport (in general, sediments with higher TOC content and finer grain-size distribution can have higher contaminant burdens than sediments from a given river section that have less TOC and greater amounts of coarse-grained sediments). Physiochemical sediment characteristics are highly variable among monitoring sites along the Columbia River. Sediment grain characterization and TOC analysis should be included in interpretations of sediment-monitoring data.
Date: April 1, 1995
Creator: Blanton, M. L.; Gardiner, W. W. & Dirkes, R. L.
Partner: UNT Libraries Government Documents Department

LLNL NESHAPs 1996 Annual Report

Description: This annual report is prepared pursuant to the National Emissions Standards for Hazardous Air Pollutants (NESHAPs) 40 CFR Part 61, Subpart H; Subpart H governs radionuclide emissions to air from Department of Energy (DOE) facilities. NESHAPs limits the emission of radionuclides to the ambient air from DOE facilities to levels resulting in an annual effective dose equivalent (EDE) of 10 mrem (10 microsieverts) to any member of the public. The EDEs for the Lawrence Livermore National Laboratory (LLNL) site-wide maximally exposed members of the public from 1996 operations were (1) Livermore site: 0. 093 mrem (0.93 microsievert) (52% from point-source emissions, 48% from diffuse-source emissions); (2) Site 300: 0.033 mrem (0.33 microsievert) (99% from point-source, 1% from diffuse-source emissions). The EDEs were generally calculated using the EPA-approved CAP88-PC air-dispersion/dose-assessment model. Site-specific meteorological data, stack flow data, and emissions estimates based on radionuclide inventory data or continuous-monitoring systems data were the specific input to CAP88-PC for each modeled source. 5 figs., 8 tabs.
Date: January 6, 1997
Creator: Gallegos, G.M.
Partner: UNT Libraries Government Documents Department