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Waset Isolation Pilot Plant Annual Site Environmental Report for 2006
The purpose of the Waste Isolation Pilot Plant Annual Site Environmental Report for 2006 (ASER) is to provide information required by U.S. Department of Energy (DOE) Order 231.1A, Environment, Safety, and Health Reporting. Specifically, the ASER presents summary environmental data that: (a) Characterize site environmental management performance; (b) Summarize environmental occurrences and responses reported during the calendar year; (c) Confirm compliance with environmental standards and requirements; and (d) Highlight significant facility programs and efforts. The DOE Carlsbad Field Office (CBFO) and Washington TRU Solutions LLC (WTS) maintain and preserve the environmental resources at the WIPP site. DOE Order 231.1A; DOE Order 450.1, Environmental Protection Program; and DOE Order 5400.5, Radiation Protection of the Public and Environment, require that the affected environment at and near DOE facilities be monitored to ensure the safety and health of the public and the environment. This report was prepared in accordance with DOE Order 231.1A. This order requires that DOE facilities submit an ASER to the DOE Headquarters Office of the Assistant Secretary for Environment, Safety, and Health. The WIPP Hazardous Waste Facility Permit (HWFP) (No. NM4890139088-TSDF [treatment, storage, and disposal facility]) further requires that the ASER be provided to the New Mexico Environment Department …
Date:
September 26, 2007
Creator:
Washington Regulatory and Environmental Services
Object Type:
Report
System:
The UNT Digital Library
Final Summary of "Interdisciplinary Study of Shewanella oneidensis MR-1's Metabolism & Metal Reduction"
Our project focused primarily on analysis of different types of data produced by global high-throughput technologies, data integration of gene annotation, and gene and protein expression information, as well as on getting a better functional annotation of Shewanella genes. Specifically, four of our numerous major activities and achievements include the development of: statistical models for identification and expression proteomics, superior to currently available approaches (including our own earlier ones); approaches to improve gene annotations on the whole-organism scale; standards for annotation, transcriptomics and proteomics approaches; and generalized approaches for data integration of gene annotation, gene and protein expression information.
Date:
June 26, 2007
Creator:
Kolker, Eugene
Object Type:
Report
System:
The UNT Digital Library
White Paper for U.S. Army Rapid Equipping Force: Waste Heat Recovery with Thermoelectric and Lithium-Ion Hybrid Power System
By harvesting waste heat from engine exhaust and storing it in light-weight high-capacity modules, it is believed that the need for energy transport by convoys can be lowered significantly. By storing this power during operation, substantial electrical power can be provided during long periods of silent operation, while the engines are not operating. It is proposed to investigate the potential of installing efficient thermoelectric generators on the exhaust systems of trucks and other vehicles to generate electrical power from the waste heat contained in the exhaust and to store that power in advanced power packs comprised of polymer-gel lithium ion batteries. Efficient inexpensive methods for production of the thermoelectric generator are also proposed. The technology that exists at LLNL, as well as that which exists at industrial partners, all have high technology readiness level (TRL). Work is needed for integration and deployment.
Date:
November 26, 2007
Creator:
Farmer, J C
Object Type:
Report
System:
The UNT Digital Library
TECHNICAL BASIS DOCUMENT OF MARSSIM FIELD CALIBRATION FOR QUANTIFICATION OF CS-137 VOLUMETRICALLY CONTAMINATED SOILS IN THE BC CONTROLLED AREA USING 2 BY 2 SODIUM IODIDE DETECTORS
The purpose of this paper is to provide the Technical Basis and Documentation for Field Calibrations of radiation measurement equipment for use in the MARSSIM Seeping Surveys of the BC Controlled Area (BCCA). The Be Controlled Area is bounded on tt1e north by (but does not include) the BCCribs & Trenches and is bounded on the south by Army Loop Road. Parts of the BC Controlled Area are posted as a Contamination Area and the remainder is posted as a Soil Contamination Area. The area is approximately 13 square miles and divided into three zones (Zone A , Zone B. and Zone C). A map from reference 1 which shows the 3 zones is attached. The MARSSIM Scoping Surveys are intended 10 better identify the boundaries of the three zones based on the volumetric (pCi/g) contamination levels in the soil. The MARSSIM Field Calibration. reference 2. of radiation survey instrumentation will determine the Minimum Detectable Concentration (MDC) and an algorithm for converting counts to pCi/g. The instrumentation and corresponding results are not intended for occupational radiation protection decisions or for the release of property per DOE Order 5400.5.
Date:
October 26, 2007
Creator:
JL, PAPPIN
Object Type:
Report
System:
The UNT Digital Library
Remaining Sites Verification Package for 132-H-1, 116-H Reactor Stack Burial Site, Waste Site Reclassification Form 2006-053
The 132-H-1 waste site includes the 116-H exhaust stack burial trench and the buried stack foundation (which contains an embedded vertical 15-cm (6-in) condensate drain line). The 116-H reactor exhaust stack and foundation were decommissioned and demolished using explosives in 1983, with the rubble buried in situ beneath clean fill at least 1 m (3.3 ft) thick. Residual concentrations support future land uses that can be represented by a rural-residential scenario and pose no threat to groundwater or the Columbia River based on RESRAD modeling.
Date:
June 26, 2007
Creator:
Dittmer, L. M.
Object Type:
Report
System:
The UNT Digital Library
Estimate of Hanford Waste Rheology and Settling Behavior
The U.S. Department of Energy (DOE) Office of River Protection’s Waste Treatment and Immobilization Plant (WTP) will process and treat radioactive waste that is stored in tanks at the Hanford Site. Piping, pumps, and mixing vessels have been selected to transport, store, and mix the high-level waste slurries in the WTP. This report addresses the analyses performed by the Rheology Working Group (RWG) and Risk Assessment Working Group composed of Pacific Northwest National Laboratory (PNNL), Bechtel National Inc. (BNI), CH2M HILL, DOE Office of River Protection (ORP) and Yasuo Onishi Consulting, LLC staff on data obtained from documented Hanford waste analyses to determine a best-estimate of the rheology of the Hanford tank wastes and their settling behavior. The actual testing activities were performed and reported separately in referenced documentation. Because of this, many of the required topics below do not apply and are so noted.
Date:
October 26, 2007
Creator:
Poloski, Adam P.; Wells, Beric E.; Tingey, Joel M.; Mahoney, Lenna A.; Hall, Mark N.; Thomson, Scott L. et al.
Object Type:
Report
System:
The UNT Digital Library
Compulsory Deep Mixing of 3He and CNO Isotopes on the First Giant Branch
We have found a deep-mixing process which occurs during First Giant Branch (FGB) evolution. It begins at the point in evolution where the surface convection zone (SCZ), having previously grown in size, starts to shrink, and it is driven by a local minimum that develops in the mean molecular weight as a result of the burning of {sup 3}He. This mixing can solve two important observational problems. One is why the interstellar medium (ISM) has not been considerably enriched in {sup 3}He since the Big Bang. The other is why products of nucleosynthesis such as {sup 13}C are progressively enriched on the upper FGB, when classical stellar modeling says that no further enrichment should take beyond the First Dredge-Up (FDU) episode, somewhat below the middle of the FGB.
Date:
July 26, 2007
Creator:
Eggleton, P P; Dearborn, D P & Lattanzio, J
Object Type:
Article
System:
The UNT Digital Library
Synthesis of Non-molecular Nitrogen Phases at Mbar Pressures by Direct Laser-heating
Direct laser heating of molecular N2 to above 1400 K at 120-130 GPa results in the formation of a reddish amorphous phase and a transparent crystalline solid above 2000 K. Raman and x-ray data confirm that the transparent phase is cubic-gauche nitrogen (cg-N), while the reddish color of the amorphous phase might indicate the presence of N=N dish bonds. The quenched amorphous phase is stable down to at least 70GPa, analogous to cg-N, and could be a new non-molecular phase or an extension of the already known {eta}-phase. A chemo-physical phase diagram is presented which emphasizes the difference between pressure- and temperature-induced transitions from molecular to non-molecular solids, as found in other low Z systems.
Date:
March 26, 2007
Creator:
Lipp, M. J.; Klepeis, J. P.; Baer, B. J.; Cynn, H.; Evans, W. J.; Iota, V. et al.
Object Type:
Article
System:
The UNT Digital Library
TANK 5 SAMPLING
Tank 5 at the Savannah River Site has been used to store high level waste and is currently undergoing waste removal processes in preparation for tank closure. Samples were taken from two locations to determine the contents in support of Documented Safety Analysis (DSA) development for chemical cleaning. These samples were obtained through the use of the Drop Core Sampler and the Snowbank Sampler developed by the Engineered Equipment & Systems (EES) group of the Savannah River National Laboratory (SRNL).
Date:
November 26, 2007
Creator:
Vrettos, N; William Cheng, W & Thomas Nance, T
Object Type:
Article
System:
The UNT Digital Library
Fast Prediction of HCCI and PCCI Combustion with an Artificial Neural Network-Based Chemical Kinetic Model
We have added the capability to look at in-cylinder fuel distributions using a previously developed ignition model within a fluid mechanics code (KIVA3V) that uses an artificial neural network (ANN) to predict ignition (The combined code: KIVA3V-ANN). KIVA3V-ANN was originally developed and validated for analysis of Homogeneous Charge Compression Ignition (HCCI) combustion, but it is also applicable to the more difficult problem of Premixed Charge Compression Ignition (PCCI) combustion. PCCI combustion refers to cases where combustion occurs as a nonmixing controlled, chemical kinetics dominated, autoignition process, where the fuel, air, and residual gas mixtures are not necessarily as homogeneous as in HCCI combustion. This paper analyzes the effects of introducing charge non-uniformity into a KIVA3V-ANN simulation. The results are compared to experimental results, as well as simulation results using a more physically representative and computationally intensive code (KIVA3V-MPI-MZ), which links a fluid mechanics code to a multi-zone detailed chemical kinetics solver. The results indicate that KIVA3V-ANN produces reasonable approximations to the more accurate KIVA3V-MPI-MZ at a much reduced computational cost.
Date:
September 26, 2007
Creator:
Piggott, W. T.; Aceves, S. M.; Flowers, D. L. & Chen, J. Y.
Object Type:
Article
System:
The UNT Digital Library
Numerical Modeling of Coupled Groundwater and Surface Water Interactions in an Urban Setting
The Dominguez Channel Watershed (DCW), located in the southern portion of Los Angeles County (Figure A.1), drains about 345 square miles into the Los Angeles Harbor. The cities and jurisdictions in DCW are shown in Figure A.2. The largest of these include the cities of Los Angeles, Carson, and Torrance. This watershed is unique in that 93% of its land area is highly developed (i.e. urbanized). The watershed boundaries are defined by a complex network of storm drains and flood control channels, rather than being defined by natural topography. Table (1) shows a summary of different land uses in the Dominguez Channel Watershed (MEC, 2004). The Dominguez Watershed has the highest impervious area of all watersheds in the Los Angeles region. The more impervious the surface, the more runoff is generated during a storm. Storm water runoff can carry previously accumulated contaminants and transport them into receiving water systems. Point sources such as industrial wastewater and municipal sewage as well as urban runoff from commercial, residential, and industrial areas are all recognized as contributors to water quality degradation at DWC. Section 303(d) of the 1972 Federal Clean Water Act (CWA) requires states to identify and report all waters not meeting …
Date:
September 26, 2007
Creator:
Rihani, J F & Maxwell, R M
Object Type:
Report
System:
The UNT Digital Library
A Linear Scaling Three Dimensional Fragment Method for Large ScaleElectronic Structure Calculations
We present a novel linear scaling ab initio total energyelectronic structure calculation method, which is simple to implement,easily to parallelize, and produces essentially thesame results as thedirect ab initio method, while it could be thousands of times faster.Using this method, we have studied the dipole moments of CdSe quantumdots, and found both significant bulk and surface contributions. The bulkdipole contribution cannot simply be estimated from the bulk spontaneouspolarization value by a proportional volume factor. Instead it has ageometry dependent screening effect. The dipole moment also produces astrong internal electric field which induces a strong electron holeseparation.
Date:
July 26, 2007
Creator:
Wang, Lin-Wang; Zhao, Zhengji & Meza, Juan
Object Type:
Article
System:
The UNT Digital Library
Catalytic Deprotection of Acetals In Strongly Basic Solution Usinga Self-Assembled Supramolecular 'Nanozyme'
Acetals are among the most commonly used protecting groups for aldehydes and ketones in organic synthesis due to their ease of installation and resistance to cleavage in neutral or basic solution.[1] The common methods for hydrolyzing acetals almost always involve the use of either Broensted acid or Lewis acid catalysts.[2] Usually aqueous acids or organic solutions acidified with organic or inorganic acids have been used for reconversion of the acetal functionality to the corresponding carbonyl group; however, recently a number of reports have documented a variety of strategies for acetal cleavage under mild conditions. These include the use of Lewis acids such as bismuth(III)[3] or cerium(IV),[4, 5] functionalized silica gel, such as silica sulfuric acid[6] or silica-supported pyridinium p-toluene sulfonate,[7] or the use of silicon-based reagents such as TESOTf-2,6-Lutidine.[8] Despite these mild reagents, all of the above conditions require either added acid or overall acidic media. Marko and co-workers recently reported the first example of acetal deprotection under mildly basic conditions using catalytic cerium ammonium nitrate at pH 8 in a water-acetonitrile solution.[5] Also recently, Rao and co-workers described a purely aqueous system at neutral pH for the deprotection of acetals using {beta}-cyclodextrin as the catalyst.[9] Herein, we report the …
Date:
July 26, 2007
Creator:
Pluth, Michael D.; Bergman, Robert G. & Raymond, Kenneth N.
Object Type:
Article
System:
The UNT Digital Library
Diagnostic evaluation of a multiplexed RT-PCR microsphere array assay for the detection of foot-and-mouth disease virus and look-alike disease viruses
A high-throughput multiplexed assay was developed for the differential laboratory diagnosis of foot-and-mouth disease virus (FMDV) from viruses which cause clinically similar diseases of livestock. This assay simultaneously screens for five RNA and two DNA viruses using multiplexed reverse transcription PCR (mRT-PCR) amplification coupled with a microsphere hybridization array and flow-cytometric detection. Two of the seventeen primer-probe sets included in this multiplex assay were adopted from previously characterized real-time RT-PCR (rRT-PCR) assays for FMDV. The diagnostic accuracy of the mRT-PCR was evaluated using 287 field samples, including 248 (true positive n= 213, true negative n=34) from suspect cases of foot-and-mouth disease collected from 65 countries between 1965 and 2006 and 39 true negative samples collected from healthy animals. The mRT-PCR assay results were compared with two singleplex rRT-PCR assays, using virus isolation with antigen-ELISA as the reference method. The diagnostic sensitivity of the mRT-PCR assay for FMDV was 93.9% [95% C.I. 89.8-96.4%], compared to 98.1% [95% C.I. 95.3-99.3%] for the two singleplex rRT-PCR assays used in combination. In addition, the assay could reliably differentiate between FMDV and other vesicular viruses such as swine vesicular disease virus and vesicular exanthema of swine virus. Interestingly, the mRT-PCR detected parapoxvirus (n=2) and bovine …
Date:
July 26, 2007
Creator:
Hindson, B J; Reid, S M; Baker, B R; Ebert, K; Ferris, N P; Bentley Tammero, L F et al.
Object Type:
Article
System:
The UNT Digital Library
Status of the Nif Power Conditioning System
The NIF Power Conditioning System provides the pulsed excitation required to drive flashlamps in the laser's optical amplifiers. Modular in design, each of the 192 Main Energy Storage Modules (MESMs) storage up to 2.2 MJ of electrical energy in its capacitor bank before delivering the energy to 20 pairs of flashlamps in a 400 {micro}s pulse (10% power points). The peak current of each MESM discharge is 0.5 MA. Production, installation, commissioning and operation of the NIF Power Conditioning continue to progress rapidly, with the goals of completing accelerated production in late 2007 and finishing commissioning by early 2008, all the while maintaining an aggressive operations schedule. To date, more than 80% of the required modules have been assembled, shipped and installed in the facility, representing more that 240 MJ of stored energy available for driving NIF flashlamps. The MESMs have displayed outstanding reliability during daily, multiple-shift operations.
Date:
July 26, 2007
Creator:
Arnold, P.; Hulsey, S.; Ullery, G.; Petersen, D.; Pendleton, D.; Ollis, C. et al.
Object Type:
Article
System:
The UNT Digital Library
TECHNICAL BASIS DOCUMENT OF MARSSIM FIELD CALIBRATION FOR QUANTIFICATION OF CS-137 VOLUMETRICALLY CONTAMINTED SOILS IN THE BC CONTROLLED AREA USING A 4 BY 4 BY 16 INCH SODIUM IODIDE DETECTOR
The purpose of this paper is to provide the Technical Basis and Documentation for Field Calibrations of radiation measurement equipment for use in the MARSSIM Seeping Surveys of the BC Controlled Area (BCCA). The Be Controlled Area is bounded on tt1e north by (but does not include) the BCCribs & Trenches and is bounded on the south by Army Loop Road. Parts of the BC Controlled Area are posted as a Contamination Area and the remainder is posted as a Soil Contamination Area. The area is approximately 13 square miles and divided into three zones (Zone A , Zone B. and Zone C). A map from reference 1 which shows the 3 zones is attached. The MARSSIM Scoping Surveys are intended 10 better identify the boundaries of the three zones based on the volumetric (pCi/g) contamination levels in the soil. The MARSSIM Field Calibration. reference 2. of radiation survey instrumentation will determine the Minimum Detectable Concentration (MDC) and an algorithm for converting counts to pCi/g. The instrumentation and corresponding results are not intended for occupational radiation protection decisions or for the release of property per DOE Order 5400.5.
Date:
October 26, 2007
Creator:
JL, PAPPIN
Object Type:
Report
System:
The UNT Digital Library
Low doses of alpha particles do not induce sister chromatid exchanges in bystander Chinese hamster cells defective in homologous recombination
We reported previously that the homologous recombinational repair (HRR)-deficient Chinese hamster mutant cell line irs3 (deficient in the Rad51 paralog Rad51C) showed only a 50% spontaneous frequency of sister chromatid exchange (SCE) as compared to parental wild-type V79 cells. Furthermore, when irradiated with very low doses of alpha particles, SCEs were not induced in irs3 cells, as compared to a prominent bystander effect observed in V79 cells (Nagasawa et al., Radiat. Res. 164, 141-147, 2005). In the present study, we examined additional Chinese hamster cell lines deficient in the Rad51 paralogs Rad51C, Rad51D, Xrcc2, and Xrcc3 as well as another essential HRR protein, Brca2. Spontaneous SCE frequencies in non-irradiated wild-type cell lines CHO, AA8 and V79 were 0.33 SCE/chromosome, whereas two Rad51C-deficient cell lines showed only 0.16 SCE/chromosome. Spontaneous SCE frequencies in cell lines defective in Rad51D, Xrcc2, Xrcc3, and Brca2 ranged from 0.23-0.33 SCE/chromosome, 0-30% lower than wild-type cells. SCEs were induced significantly 20-50% above spontaneous levels in wild-type cells exposed to a mean dose of 1.3 mGy of alpha particles (<1% of nuclei traversed by an alpha particle). However, induction of SCEs above spontaneous levels was minimal or absent after {alpha}-particle irradiation in all of the HRR-deficient cell …
Date:
October 26, 2007
Creator:
Nagasawa, H; Wilson, P F; Chen, D J; Thompson, L H; Bedford, J S & Little, J B
Object Type:
Article
System:
The UNT Digital Library
Diamond Amplified Photocathodes
High-average-current linear electron accelerators require photoinjectors capable of delivering tens to hundreds of mA average current, with peak currents of hundreds of amps. Standard photocathodes face significant challenges in meeting these requirements, and often have short operational lifetimes in an accelerator environment. We report on recent progress toward development of secondary emission amplifiers for photocathodes, which are intended to increase the achievable average current while protecting the cathode from the accelerator. The amplifier is a thin diamond wafer which converts energetic (few keV) primary electrons into hundreds of electron-hole pairs via secondary electron emission. The electrons drift through the diamond under an external bias and are emitted into vacuum via a hydrogen-terminated surface with negative electron affinity (NEA). Secondary emission gain of over 200 has been achieved. Two methods of patterning diamond, laser ablation and reactive-ion etching (RIE), are being developed to produce the required geometry. A variety of diagnostic techniques, including FTIR, SEM and AFM, have been used to characterize the diamonds.
Date:
November 26, 2007
Creator:
Smedley, J.; Ben-Zvi, Ilan; Bohon, J.; Chang, X.; Grover, R.; Isakovic, A. et al.
Object Type:
Article
System:
The UNT Digital Library
A review of ground-based heavy-ion radiobiology relevant to space radiation risk assessment: Part II. Cardiovascular and immunological effects
The future of manned space flight depends on an analysis of the numerous potential risks of travel into deep space. Currently no radiation dose limits have been established for these exploratory missions. To set these standards more information is needed about potential acute and late effects on human physiology from appropriate radiation exposure scenarios, including pertinent radiation types and dose rates. Cancer risks have long been considered the most serious late effect from chronic daily relatively low-dose exposures to the complex space radiation environment. However, other late effects from space radiation exposure scenarios are under study in ground-based accelerator facilities and have revealed some unique particle radiation effects not observed with conventional radiations. A comprehensive review of pertinent literature that considers tissue effects of radiation leading to functional detriments in specific organ systems has recently been published (NCRP National Council on Radiation Protection and Measurements, Information Needed to Make Radiation Protection Recommendations for Space Missions Beyond Low-Earth Orbit, Report 153, Bethesda, MD, 2006). This paper highlights the review of two non-cancer concerns from this report: cardiovascular and immunological effects.
Date:
February 26, 2007
Creator:
Blakely, Eleanor A. & Chang, Polly Y.
Object Type:
Article
System:
The UNT Digital Library
DETAILED ANALYSIS OF THE MOST PROMISING ALTERNATIVES TO USING GRANULAR ACTIVATED CARBON TO TREAT 200-ZP-1 GROUNDWATER AND 200-PW-1 SOIL VAPOR
This document presents a detailed evaluation of selected alternative treatment options to granular activated carbon (GAC) for removing carbon tetrachloride generated from the groundwater pump-and-treat system at the 200-ZP-I Operable Unit (OU) in the 200 West Area of the Hanford Site. This evaluation of alternative treatment options to GAC is also applicable to the vadose zone soil vapor extraction (SVE) system at the 200-PW-l OU, which is also located in the Hanford Site's 200 West Area.
Date:
November 26, 2007
Creator:
BYRNES ME, KALMAR JA
Object Type:
Report
System:
The UNT Digital Library
Aerosol climate effects and air quality impacts from 1980 to 2030
We investigate aerosol effects on climate for 1980, 1995 (meant to reflect present-day) and 2030 using the NASA Goddard Institute for Space Studies climate model coupled to an on-line aerosol source and transport model with interactive oxidant and aerosol chemistry. Aerosols simulated include sulfates, organic matter (OM), black carbon (BC), sea-salt and dust and additionally, the amount of tropospheric ozone is calculated, allowing us to estimate both changes to air quality and climate for different time periods and emission amounts. We include both the direct aerosol effect and indirect aerosol effects for liquid-phase clouds. Future changes for the 2030 A1B scenario are examined, focusing on the Arctic and Asia, since changes are pronounced in these regions. Our results for the different time periods include both emission changes and physical climate changes. We find that the aerosol indirect effect (AIE) has a large impact on photochemical processing, decreasing ozone amount and ozone forcing, especially for the future (2030-1995). Ozone forcings increase from 0 to 0.12 Wm{sup -2} and the total aerosol forcing increases from -0.10 Wm{sup -2} to -0.94 Wm{sup -2} (AIE increases from -0.13 to -0.68 Wm{sup -2}) for 1995-1980 versus 2030-1995. Over the Arctic we find that compared to …
Date:
November 26, 2007
Creator:
Menon, Surabi; Menon, Surabi; Unger, Nadine; Koch, Dorothy; Francis, Jennifer; Garrett, Tim et al.
Object Type:
Article
System:
The UNT Digital Library
Mn l3,2 x-ray absorption spectroscopy and magnetic circulardichroism in ferromagnetic ga1-xmnxp
We have measured the X-ray absorption (XAS) and X-ray magnetic circular dichroism (XMCD) at the Mn L{sub 3,2} edges in ferromagnetic Ga{sub 1-x}Mn{sub x}P films for 0.018 {le} x {le} 0.042. Large XMCD asymmetries at the L{sub 3} edge indicate significant spin-polarization of the density of states at the Fermi energy. The spectral shapes of the XAS and XMCD are nearly identical with those for Ga{sub 1-x}Mn{sub x}As indicating that the hybridization of Mn d states and anion p states is similar in the two materials. Finally, compensation with sulfur donors not only lowers the ferromagnetic Curie temperature but also reduces the spin polarization of the hole states.
Date:
July 26, 2007
Creator:
Stone, P.R.; Scarpulla, M.A.; Farshchi, R.; Sharp, I.D.; Beeman,J.W.; Yu, K.M. et al.
Object Type:
Article
System:
The UNT Digital Library
Advances in National Capabilities for Consequence Assessment Modeling of Airborne Hazards
This paper describes ongoing advancement of airborne hazard modeling capabilities in support of multiple agencies through the National Atmospheric Release Advisory Center (NARAC) and the Interagency Atmospheric Modeling and Atmospheric Assessment Center (IMAAC). A suite of software tools developed by Lawrence Livermore National Laboratory (LLNL) and collaborating organizations includes simple stand-alone, local-scale plume modeling tools for end user's computers, Web- and Internet-based software to access advanced 3-D flow and atmospheric dispersion modeling tools and expert analysis from the national center at LLNL, and state-of-the-science high-resolution urban models and event reconstruction capabilities.
Date:
November 26, 2007
Creator:
Nasstrom, J; Sugiyama, G; Foster, K; Larsen, S; Kosovic, B; Eme, B et al.
Object Type:
Article
System:
The UNT Digital Library
A Site Wide Perspective on Uranium Geochemistry at the Hanford Site
Uranium (U) is an important risk-driving contaminant at the Hanford Site. Over 200,000 kg have been released to the vadose zone over the course of site operations, and a number of vadose zone and groundwater plumes containing the uranyl cation [UO22+, U(VI)] have been identified. U is recognized to be of moderate-to-high mobility, conditions dependent. The site is currently making decisions on several of these plumes with long-lasting implications, and others are soon to come. Uranium is one of nature’s most intriguing and chemically complex elements. The fate and transport of U(VI) has been studied over the long lifetime of the Hanford Site by various contractors, along with the Pacific Northwest National Laboratory (PNNL) and its collaborators. Significant research has more recently been contributed by the national scientific community with support from the U.S. Department of Energy’s (DOE) Office of Science through its Environmental Remediation Sciences Division (ERSD). This report represents a first attempt to integrate these findings into a cohesive view of the subsurface geochemistry of U at the Hanford Site. The objective is to inform all interested Hanford parties about the in-ground inventory of U and its geochemical behavior. This report also comments on the prospects for the …
Date:
October 26, 2007
Creator:
Zachara, John M.; Brown, Christopher F.; Christensen, J. N.; Davis, Jim A.; Dresel, P. Evan; Liu, Chongxuan et al.
Object Type:
Report
System:
The UNT Digital Library