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Analysis of the Thermal Performance of Tierra I--A Low-Energy High-Mass Residence

Description: A low-energy concrete house was designed using passive solar strategies to consume 70% less heating and cooling energy than a base case that conformed to the 1996 Home Energy Rating System (HERS) and the 1995 Model Energy Code (MEC). The performance of this house was then evaluated using computer simulations and measured data. The house, Tierra I, was monitored from July 22, 1996, through October 14, 1997. A Short Term Energy Monitoring (STEM) test was done November 19 to December 10, 1996. Computer simulations of the house were done using SUNREL, an updated version of the hourly data simulation package SERI-RES. The SUNREL model of the house was calibrated using both short- and long-term data. The house achieved energy savings of 56%, below the goal of 70%. The lower than expected savings resulted from problems with the window modeling. As a result, during the design phase the solar gains were overestimated causing an underestimate in the level of insulation necessary to achieve the savings goal. For very low-energy passive solar buildings, it is apparent that very accurate window modeling is required. It also became apparent that accurate ground models are required as well because ground-heat loss accounts for a significant portion of the total heat loss in low-energy buildings.
Date: May 31, 2001
Creator: Smith, M. W.
Partner: UNT Libraries Government Documents Department
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Authentication Procedures - The Procedures and Integration Working Group

Description: Authentication is how we establish trust in monitoring systems and measurements to verify compliance with, for example, the storage of nuclear weapons material. Authentication helps assure the monitoring party that accurate and reliable information is provided by any measurement system and that any irregularities are detected. The U.S. is developing its point of view on the procedures for authentication of monitoring systems now planned or contemplated for arms reduction and control applications. The authentication of a system utilizes a set of approaches, including: functional testing using trusted calibration sources, evaluation of documentation, evaluation of software, evaluation of hardware, random selection of hardware and software, tamper-indicating devices, and operational procedures. Authentication of measurement systems should occur throughout their lifecycles, starting with the elements of design, and moving to off-site authentication, on-siste authentication, and continuing with authentication following repair. The most important of these is the initial design of systems. Hardware and software design criteria and procurement decisions can make future authentication relatively straightforward or conversely very difficult. Facility decisions can likewise ease the procedures for authentication since reliable and effective monitoring systems and tampering indicating devices can help provide the assurance needed in the integrity of such items as measurement systems, spare equipment, and reference sources. This paper will summarize the results of the U.S. Authentication Task Force discussion on the role of procedures in authentication.
Date: May 31, 2001
Creator: Kouzes, Richard T.; Bratcher, Leigh; Gosnell, Tom; Langner, Diana; MacArthur, D.; Mihalczo, John T. et al.
Partner: UNT Libraries Government Documents Department
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Constitutive Relations for Unsaturated Flow in a Fracture Network

Description: A commonly used approach for modeling water flow in unsaturated fractured rocks is the continuum approach, in which the constitutive relation models originally developed for porous media have often been borrowed to represent constitutive relations for the fracture continuum. While these models have been successfully used for soils and other porous media, their usefulness and limitations have not been investigated for the fracture continuum. The objective of this study is to present an evaluation of the commonly used van Genuchten and Brooks-Corey models and to develop improved constitutive relation models based on the evaluation results.
Date: May 31, 2001
Creator: Liu, H. H. & Bodvarsson, G. S.
Partner: UNT Libraries Government Documents Department
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DEVELOPMENT OF IMPROVED CATALYSTS FOR THE SELECTIVE CATALYTIC REDUCTION OF NITROGEN OXIDES WITH HYDROCARBONS

Description: Significant work has been done by the investigators on the cerium oxide-copper oxide based sorbent/catalysts for the combined removal of sulfur and nitrogen oxides from the flue gases of stationary sources. A relatively wide temperature window was established for the use of alumina-supported cerium oxide-copper oxide mixtures as regenerable sorbents for SO{sub 2} removal. Preliminary evaluation of these sorbents as catalysts for the selective reduction of NO{sub x} gave promising results with ammonia, but indicated low selectivity when methane was used as the reductant. Since the replacement of ammonia by another reductant is commercially very attractive, in this project, four research components will be undertaken. The investigation of the reaction mechanism, the first component, will help in the selection of promoters to improve the catalytic activity and selectivity of the sorbents in the SCR with methane. This will result in new catalyst formulations (second component). If this research is successful, the combined SO{sub 2}-NO{sub x} removal process based on alumina-supported copper oxide-ceria sorbent/catalysts will become very attractive for commercial applications. The objective of the third component of the project is to develop an alternative SCR process using another inexpensive fuel, residual fuel oil, instead of natural gas. This innovative proposal is based on very scant evidence concerning the good performance of coked catalysts in the selective reduction of NO and if proven to work the process will certainly be commercially viable. The fourth component of the project involves our industrial partner TDA Research, and the objective is to evaluate long-term stability and durability of the prepared sorbent/catalysts. In the first year of the project, the catalysts were investigated by the temperature-programmed reduction (TPR) technique. The results from TPR indicated that the interaction with support appears to promote reduction at lower temperatures. Copper oxide in excess of monolayer coverage reduces at …
Date: May 31, 2001
Creator: Akyurtlu, Dr. Ates & Akyurtlu, Dr. Jale F.
Partner: UNT Libraries Government Documents Department
open access

Dynamic Characterization Testing of Wind Turbines

Description: The U.S. Department of Energy (DOE), in conjunction with the U.S. wind industry, is supporting the development and commercialization of utility-grade wind turbines. Under the Certification Program, the DOE, through the National Renewable Energy Laboratory (NREL) will assist the U.S. industry in obtaining American Association for Laboratory Accreditation (A2LA)-type certification for their class of wind turbine. As part of the Certification Program, NREL is conducting a suite of certification tests that are specified by the International Electro-technical Commission standards. One emerging certification requirement is to characterize the dynamic behavior of the wind turbine's operation. Therefore, the purpose of the dynamic characterization tests is to document the wind turbine's fundamental dynamic characteristics under critical operational modes and fault conditions in light of turbine design specifications. Some of the dynamic characteristics that we determine from testing include the conformation of fundamental structural vibration frequencies and the system's dynamic response to typical rated and extreme modes of operation. This paper discusses NREL's approach in designing and implementing a dynamic characterization test for commercial wind turbines. One important objective of the dynamic characterization test is to provide a Certification Agent with test data to show that the wind turbine's mechanical equipment is operating within design vibration limits. For NREL's industry participant, the test results are an indication of the wind system's overall quality of mechanical operation that can be used to compare with established industry standards for a wind system's response under typical and extreme operating conditions.
Date: May 31, 2001
Creator: Osgood, R.
Partner: UNT Libraries Government Documents Department
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Electrochemical Processes for In-Situ Treatment of Contaminated Soils - Final Report - 09/15/1996 - 01/31/2001

Description: This project will study electrochemical processes for the in situ treatment of soils contaminated by mixed wastes, i.e., organic and inorganic. Soil samples collected form selected DOE waste sites will be characterized for specific organic and metal contaminants and hydraulic permeability. The soil samples are then subject to desorption experiments under various physical-chemical conditions such as pH and the presence of surfactants. Batch electro-osmosis experiments will be conducted to study the transport of contaminants in the soil-water systems. Organic contaminants that are released from the soil substrate will be treated by an advanced oxidation process, i.e., electron-Fantan. Finally, laboratory reactor integrating the elector-osmosis and elector-Fantan processes will be used to study the treatment of contaminated soil in situ.
Date: May 31, 2001
Creator: Huang, Chin-Pao
Partner: UNT Libraries Government Documents Department
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Energy Consumption and Expenditure Projections by Population Group on the Basis on the Annual Energy Outlook 2000 Forecast.

Description: The changes in the patterns of energy use and expenditures by population group are analyzed by using the 1993 and 1997 Residential Energy Consumption Surveys. Historically, these patterns have differed among non-Hispanic White households, non-Hispanic Black households, and Hispanic households. Patterns of energy use and expenditures are influenced by geographic and metropolitan location, the composition of housing stock, economic and demographic status, and the composition of energy use by end-use category. As a consequence, as energy-related factors change across groups, patterns of energy use and expenditures also change. Over time, with changes in the composition of these factors by population group and their variable influences on energy use, the impact on energy use and expenditures has varied across these population groups.
Date: May 31, 2001
Creator: Poyer, D. A. & Sciences, Decision and Information
Partner: UNT Libraries Government Documents Department
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Export Controls: Regulatory Change Needed to Comply with Missile Technology Licensing Requirements

Description: A letter report issued by the General Accounting Office with an abstract that begins "The United States and several major trading partners created the Missile Technology Control Regime in 1987 to control the spread of missile technology. To carry out the U.S. commitment to the agreement, Congress passed the National Defense Authorization Act of Fiscal Year 1991, which amended two U.S. export control statutes: the Export Administration Act and the Arms Export Control Act. Two federal agencies, the Department of Commerce and the Department of State, are responsible for implementing the regulations for controlling missile technology exports. This report discusses whether the regulations for controlling the export of Missile Technology Control Regime items (1) are consistent with U.S. law and (2) provide a consistent U.S. policy on the control of missile technology. GAO found that Commerce's export regulations are inconsistent with an amendment to the Export Administration Act that requires an individual export license for all controlled dual-use missile equipment and technology to all countries. Commerce's regulations do not require licenses for the export of controlled missile equipment and technology to Canada. Commerce did not cite any section of this statute or its legislative history to justify the inconsistency between its regulations and the statutory requirement. GAO found that State's export regulations are consistent with the amendment to the Arms Export Control Act. The inconsistency between Commerce's regulatory exemption and the Export Administration Act, along with different interpretations by Commerce and State of congressional intent, contributes to a divided U.S. government policy toward Canada and toward missile proliferation."
Date: May 31, 2001
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department
open access

Fine Anthracite Coal Washing Using Spirals

Description: The spiral performed well in cleaning the coarse 8 x 16 mesh size fraction, as demonstrated by the Ep ranging from 0.091 to 0.177. This is in line with typical spiral performance. In addition, the presence of the coarser size fraction did not significantly affect spiral performance on the typical 16 x 100 mesh fraction, in which the Ep ranged from 0.144 to 0.250. Changes in solids concentration and flow rate did not show a clear correlation with spiral performance. However, for difficult-to-clean coals with high near-gravity material, such as this anthracite, a single-stage spiral cleaning such a wide size fraction may not be able to achieve the clean coal ash and yield specifications required. In the first place, while the performance of the spiral on the coarse 8 x 16 mesh fraction is good with regard to Ep, the cutpoints (SG50s) are high (1.87 to 1.92), which may result in a clean coal with a higher-than-desired ash content. And second, the combination of the spiral's higher overall cutpoint (1.80) with the high near-gravity anthracite results in significant misplaced material that increases the clean coal ash error. In a case such as this, one solution may be to reclean the clean coal and middlings from the first-stage spiral in a second stage spiral.
Date: May 31, 2001
Creator: Killmeyer, R.P.; Zandhuis, P.H.; Ciocco, M.V.; Weldon, W.; West, T. & Petrunak, D.
Partner: UNT Libraries Government Documents Department
open access

FUELS IN SOIL TEST KIT: FIELD USE OF DIESEL DOG SOIL TEST KITS

Description: Western Research Institute (WRI) is commercializing Diesel Dog Portable Soil Test Kits for performing analysis of fuel-contaminated soils in the field. The technology consists of a method developed by WRI (U.S. Patents 5,561,065 and 5,976,883) and hardware developed by WRI that allows the method to be performed in the field (patent pending). The method is very simple and does not require the use of highly toxic reagents. The aromatic components in a soil extract are measured by absorption at 254 nm with a field-portable photometer. WRI added significant value to the technology by taking the method through the American Society for Testing and Materials (ASTM) approval and validation processes. The method is designated ASTM Method D-5831-96, Standard Test Method for Screening Fuels in Soils. This ASTM designation allows the method to be used for federal compliance activities. In FY 99, twenty-five preproduction kits were successfully constructed in cooperation with CF Electronics, Inc., of Laramie, Wyoming. The kit components work well and the kits are fully operational. In the calendar year 2000, kits were provided to the following entities who agreed to participate as FY 99 and FY 00 JSR (Jointly Sponsored Research) cosponsors and use the kits as opportunities arose for field site work: Wyoming Department of Environmental Quality (DEQ) (3 units), F.E. Warren Air Force Base, Gradient Corporation, The Johnson Company (2 units), IT Corporation (2 units), TRC Environmental Corporation, Stone Environmental, ENSR, Action Environmental, Laco Associates, Barenco, Brown and Caldwell, Dames and Moore Lebron LLP, Phillips Petroleum, GeoSyntek, and the State of New Mexico. By early 2001, ten kits had been returned to WRI following the six-month evaluation period. On return, the components of all ten kits were fully functional. The kits were upgraded with circuit modifications, new polyethylene foam inserts, and updated instruction manuals.
Date: May 31, 2001
Partner: UNT Libraries Government Documents Department
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Ion Heating by Fast Particle Induced Alfvin Turbulence

Description: A novel mechanism that directly transfers energy from Super-Alfvenic energetic ions to thermal ions in high-beta plasmas is described. The mechanism involves the excitation of compressional Alfvin eigenmodes (CAEs) in the frequency range with omega less than or approximately equal to omega(subscript ci). The broadband turbulence resulting from the large number of excited modes causes stochastic diffusion in velocity space, which transfers wave energy to thermal ions. This effect may be important on the National Spherical Torus Experiment (NSTX), and may scale up to reactor scenarios. This has important implications for low aspect ratio reactor concepts, since it potentially allows for the modification of the ignition criterion.
Date: May 31, 2001
Creator: Gates, D.; Gorelenkov, N. & White, and R.B.
Partner: UNT Libraries Government Documents Department
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Labor and Mandatory Arbitration Agreements: Background and Discussion

Description: This report discusses the Court's mandatory arbitration cases, as well as varying decisions of the U.S. circuit courts of appeals that have interpreted the Court's opinions. In addition, the report reviews legislative attempts to amend federal civil rights statutes to preclude compulsory arbitration agreements.
Date: May 31, 2001
Creator: Shimabukuro, Jon O.
Partner: UNT Libraries Government Documents Department
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Military Personnel: Higher Allowances Should Increase Use of Civilian Housing, but Not Retention

Description: A letter report issued by the General Accounting Office with an abstract that begins "Increasing the housing allowance should help satisfy servicemembers' demand for civilian housing. Of those servicemembers who receive an allowance or live in military housing, about 72 percent said that they would prefer civilian housing if the costs were the same, but only about two-thirds now live in civilian housing. Thus, if military members' housing preferences were satisfied, thousands of additional personnel would be in civilian housing instead of military housing. As the Department of Defense (DOD) increases the housing allowance during the next five years, the overall demand for civilian housing should increase, while the demand for military housing should decline. As a result, DOD should be in a better position to implement its stated policy of relying on the private sector first for housing. DOD cannot expect a substantial increase in retention solely as a result of higher housing allowances. Together, housing and housing allowances were cited by less than one percent of those surveyed as reasons for leaving the military. Overall, of those living in military housing, more were satisfied than dissatisfied. Of those living in civilian housing, a high proportion were satisfied with the homes they chose. However, 57 percent were dissatisfied with their housing allowance."
Date: May 31, 2001
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department
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Modeling of Thermal-Hydrological-Chemical Laboratory Experiments

Description: The emplacement of heat-generating nuclear waste in the potential geologic repository at Yucca Mountain, Nevada, will result in enhanced water-rock interaction around the emplacement drifts. Water present in the matrix and fractures of the rock around the drift may vaporize and migrate via fractures to cooler regions where condensation would occur. The condensate would react with the surrounding rock, resulting in mineral dissolution. Mineralized water flowing under gravity back towards the heat zone would boil, depositing the dissolved minerals. Such mineral deposition would reduce porosity and permeability above the repository, thus altering the flow paths of percolating water. The objective of this research is to use coupled thermal-hydrological-chemical (THC) models to simulate previously conducted laboratory experiments involving tuff dissolution and mineral precipitation in a boiling, unsaturated fracture. Numerical simulations of tuff dissolution and fracture plugging were performed using a modified version of the TOUGHREACT code developed at LBNL by T. Xu and K. Pruess. The models consider the transport of heat, water, gas and dissolved constituents, reactions between gas, mineral and aqueous phases, and the coupling of porosity and permeability to mineral dissolution and precipitation. The model dimensions and initial fluid chemistry, rock mineralogy, permeability, and porosity were defined using the experimental conditions. A 1-D plug-flow model was used to simulate dissolution resulting from reaction between deionized water and crushed ash flow tuff. A 2-D model was developed to simulate the flow of mineralized water through a planar fracture within a block of ash flow tuff where boiling conditions led to mineral precipitation. Matrix blocks were assigned zero permeability to confine fluid flow to the fracture, and permeability changes in the fracture were specified using the porosity cubic law relationship.
Date: May 31, 2001
Creator: Dobson, P. F.; Kneafsey, T. J.; Sonnenthal, E. L. & Spycher, Nicolas
Partner: UNT Libraries Government Documents Department
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National Personnel Records Center: Plan Needed to Show How Timeliness Goal Will Be Achieved

Description: A letter report issued by the General Accounting Office with an abstract that begins "The National Personnel Records Center (NPRC) is responsible for maintaining the official military personnel records of discharged members of the military services. Veterans frequently need their records for a variety of reasons, such as obtaining disability compensation, health benefits, GI bill education benefits, home loan guarantees, and burial in national cemeteries. However, access to these benefits has been hampered due to delays in obtaining documentation of their military service from NPRC. This report evaluates NPRC's timeliness in responding to veterans' requests for records. GAO reviewed (1) how long it took NPRC to answer veterans' requests for records and (2) whether the actions NPRC was taking would improve response time. GAO found that, in fiscal year 2000, NPRC took an average of 54 days to respond to written requests for records, answering about six percent of written requests within 10 working days. Actions NPRC was taking to respond more quickly were unlikely to significantly improve timeliness soon, and the prospects for meeting its fiscal year 2005 goal of answering 95 percent of requests within 10 working days were unclear."
Date: May 31, 2001
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department
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Optimization of the Closure-Weld Region of cylindrical Containers for Long-Term Corrosion Resistance

Description: Welded cylindrical containers are susceptible to stress corrosion cracking (SCC) in the closure-weld area. An induction coil heating technique may be used to relieve the residual stresses in the closure-weld. This technique involves localized heating of the material by the surrounding coils. The material is then cooled to room temperature by quenching. A two-dimensional axisymmetric finite element model is developed to study the effects of induction coil heating and subsequent quenching. The finite element results are validated through an experimental test. The parameters of the design are tuned to maximize the compressive stress from the outer surface to a depth that is equal to the long-term general corrosion rate of Alloy 22 (Appendix A) multiplied by the desired container lifetime. The problem is subject to geometrical and stress constraints. Two different solution methods are implemented for this purpose. First, off-the-shelf optimization software is used to obtain an optimum solution. These results are not satisfactory because of the highly nonlinear nature of the problem. The paper proposes a novel alternative: the Successive Heuristic Quadratic Approximation (SHQA) technique. This algorithm combines successive quadratic approximation with an adaptive random search. Examples and discussion are included.
Date: May 31, 2001
Creator: Ceylan, Zekai & Trabia, Mohamed B.
Partner: UNT Libraries Government Documents Department
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PRODUCTION AND SCREENING OF CARBON PRODUCTS PRECURSORS FROM COAL

Description: The authors have examined effects of blending a raw coal extract (EXT) with an extracted coal-tar pitch (ECTP). Previous reports were concerned with the addition of 15 wt% EXT, or less, on the physical characteristics of the blend and on the development of optical texture following carbonization. Two additional blends of ECTP and EXT were prepared at the 30 and 50 wt% EXT content using a procedure already described. The characteristics of the blends are presented. The density for these blended materials is not much different than the density for the blends reported earlier. The softening point temperature for the 30 wt% EXT increased to over 200 C while the softening point temperature for the 50 wt% EXT blend was too high to be determined by the Mettler method. Coke yields approximately follow the law of mixtures. The optical texture of the green cokes for the 30 and 50 wt% EXT blends is shown. Though the optical texture of the green cokes was not significantly affected where the level of EXT is 15 wt% or less, larger proportions of EXT exert a marked reduction in anisotropy. The co-processing of coal with petroleum residues or other heavy hydrocarbons at elevated temperature and pressure has received considerable attention in the research community as a means to upgrade simultaneously coal and byproducts. Heavy hydrocarbons can function as sources of hydrogen, as well as performing as a medium for dissolution and dispersion of coal fragments. However, the focus of much of the prior research has been on developing fuels, distillable liquids, or synthetic crudes. Comparatively little effort has been deliberately directed toward the production of heavier, non-distillable materials which could perform as binder and extender pitches, impregnants, or feedstocks for cokes and other carbons.
Date: May 31, 2001
Creator: Irwin, Caulton L.
Partner: UNT Libraries Government Documents Department
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A Review of Proposed Upgrades to the High Flux Isotope Reactor and Potential Impacts to Reactor Vessel Integrity

Description: The High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL) was scheduled in October 2000 to implement design upgrades that include the enlargement of the HB-2 and HB-4 beam tubes. Higher dose rates and higher radiation embrittlement rates were predicted for the two beam-tube nozzles and surrounding vessel areas. ORNL had performed calculations for the upgraded design to show that vessel integrity would be maintained at acceptable levels. Pacific Northwest National Laboratory (PNNL) was requested by the U.S. Department of Energy Headquarters (DOE/HQ) to perform an independent peer review of the ORNL evaluations. PNNL concluded that the calculated probabilities of failure for the HFIR vessel during hydrostatic tests and for operational conditions as estimated by ORNL are an acceptable basis for selecting pressures and test intervals for hydrostatic tests and for justifying continued operation of the vessel. While there were some uncertainties in the embrittlement predictions, the ongoing efforts at ORNL to measure fluence levels at critical locations of the vessel wall and to test materials from surveillance capsules should be effective in dealing with embrittlement uncertainties. It was recommended that ORNL continue to update their fracture mechanics calculations to reflect methods and data from ongoing research for commercial nuclear power plants. Such programs should provide improved data for vessel fracture mechanics calculations.
Date: May 31, 2001
Creator: Simonen, Fredric A.
Partner: UNT Libraries Government Documents Department
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Simulating Infiltration at the Large-Scale Ponded Infiltration Test, INEEL

Description: This work involved using ITOUGH2 to simulate the Large-Scale Ponded Infiltration Test (LPIT) at Idaho National Engineering and Environmental Laboratory (INEEL) in order to calibrate parameters controlling the infiltration of water in fractured basalt using a dual-permeability modeling approach. This supports the higher objective of building confidence in the use of the dual-permeability approach for modeling flow and transport in unsaturated fractured rock systems. In particular, the objective of this work is to be able to understand transport of radionuclides at INEEL and subsequently at Yucca Mountain, Nevada. A 3-D dual-permeability mesh representing the geological conditions at the LPIT was constructed as shown by the cross-section on Figure 1a. The geology consisted of surficial sediments, two separate basalt flows (A and B basalts) underlain by a low permeability sedimentary interbed (BC interbed), with a lower C basalt constituting the bottom of the model. Water was allowed to infiltrate from the pond and then pool on top of the sedimentary interbed. Water pressure and {sup 75}Se breakthroughs were simulated at four wells screened within the fractured basalt on top of the sedimentary interbed (B04N11, C04C11, B06N11, C06C11) along two radial angles and at two radial distances. Model results were calibrated to field data using ITOUGH2.
Date: May 31, 2001
Creator: Unger, Andre & Ardyth Simmons, Gudmundur Bodvarsson
Partner: UNT Libraries Government Documents Department
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Speciation, Mobility and Fate of Actinides in the Groundwater at the Hanford Site (Sept. 1999-Sept. 2002)

Description: The objectives of this project are: (1) the determination of the speciation of plutonium and other actinides (Np, U) in groundwater at the 100 and 200 areas at the Hanford Site. This includes the separation of Pu into particulate, colloidal and <1 kilo-Dalton dissolved phases and the determination of redox states and isotopic composition in each fraction; (2) the characterization of groundwater colloids, which includes submicron-sized inorganic particles and organic macromolecules (3) the prediction of the rate of transport and fate of actinides in the groundwater of the Hanford Site using a three-phase (dissolved-colloid-particulate) model.
Date: May 31, 2001
Creator: Buesseler, K. O.; Dai, M. & Repeta, D. J.
Partner: UNT Libraries Government Documents Department
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Test Results for CSTR Test 4

Description: One of the 3 technologies currently being developed for the Savannah River Salt Waste Processing Program is the Small-Tank Tetraphenylborate Process (STTP). This process uses sodium tetraphenylborate to precipitate and remove radioactive Cs from the waste and monosodium titanate to sorb and remove radioactive Sr and actinides. ORNL is demonstrating this process at the 1:4000 scale using a 20-liter continuous-flow stirred tank reactor (CSTR) system. The primary goal of Test 4 was to verify that the STTP process could achieve and maintain the necessary Cs decontamination while TPB was actively decomposing. Even with TPB being decomposed by the off-normal conditions of this test, the decontaimination factor for {sup 137}Cs obtained for the filtrate from the Slurry Concentrating Tank ranged from 47,000 to 646,000, exceeding the WAC standard.
Date: May 31, 2001
Creator: Lee, D.D.
Partner: UNT Libraries Government Documents Department
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Topical Report ''Corrosion Evaluation of LLW2 Skid-B Weld Failure Mechanisms (44139-92)

Description: An independent investigation of pipe welding leaks from the Low-Level Waste 2 (LLW2) Skid-B System for the possibilities of improper welding (IW), microbiologically influenced corrosion (MIC), sensitization, chloride pitting corrosion (CPC), and intergranular stress corrosion cracking (IGSCC) was conducted. The results show the prevailing mechanisms that caused the leaks are identified as IW, CPC, and the improper selection of weld filler material for the base metals in an environment of the North Plateau underground water. These is no evidence of MIC, sensitization, or IGSCC. The chloride pitting corrosion mechanism that took place at all the welds are also described. All the pipelines were replaced with polyvinyl chloride (PVC) for cost saving and the LLW2 Skid B System has been successfully operating since 1999. This report summarizes the findings and recommendations associated with preventive measures for future operations. The LLW2 Facility is a replacement for an existing waste treatment system. The Facility processes two different waste streams through two different ''skids.'' After seven months of operation, one of the two skids began to leak. Extensive evaluation of the corrosion mechanisms and the contributing factors are documented in this report. This report principally evaluates the physical and chemical configurations that led to the corrosion and leaks. Chloride pitting corrosion, exacerbated by weld defects, is the corrosion mechanism. The report also discusses fabrication and Quality Assurance (QA)/Quality Control (QC) actions that would have prevented their occurrence. It is believed that in the absence of either the defects or the chloride concentrations, corrosion would not have occurred. In developing the specification for processing skids to be used in the Facility, high chloride was not identified as a parameter of concern. As such, piping fabrication and inspection standards for the system did not identify more rigorous welding standards that could have prevented the corrosion and …
Date: May 31, 2001
Creator: Chang, JI Young
Partner: UNT Libraries Government Documents Department
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Transient Inverse Calibration of Hanford Site-Wide Groundwater Model to Hanford Operational Impacts - 1943 to 1996

Description: This report describes a new initiative to strengthen the technical defensibility of predictions made with the Hanford site-wide groundwater flow and transport model. The focus is on characterizing major uncertainties in the current model. PNNL will develop and implement a calibration approach and methodology that can be used to evaluate alternative conceptual models of the Hanford aquifer system. The calibration process will involve a three-dimensional transient inverse calibration of each numerical model to historical observations of hydraulic and water quality impacts to the unconfined aquifer system from Hanford operations since the mid-1940s.
Date: May 31, 2001
Creator: Cole, Charles R.; Bergeron, Marcel P.; Wurstner, Signe K.; Thorne, Paul D.; Orr, Samuel & Mckinley, Mathew I.
Partner: UNT Libraries Government Documents Department
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