'Leak detection from the transfer lines in the tank farm has been a concern for many years because of the need to minimize exposure of personnel and contamination of the environment. The leak detection box (LDB) is one line of defense, which must be maintained to meet this objective. The evaluation of a failed LDB was one item from an action plan aimed at minimizing the degradation of LDBs. The Tank 40 LDB, which failed in service, was dug up and shipped to SRTC for evaluation. During a video inspection while in service, this LDB was found to have black tubercles on the interior, which suggested possible microbial involvement. The failure point, however, was believed to have occurred in the drain line from the transfer line jacket. Visual, metallurgical, and biological analyses were performed on the LDB. The analysis results showed that there was not any adverse microbiological growth or significant localized corrosion. The corrosion of the LDB was caused by exposure to aqueous environments and was typical of carbon steel pipes in soil environments.'

We have studied the synthesis of TiC films by vacuum arc deposition and reactive magnetron sputtering over a wide range of compositions. The films were deposited on silicon and tool steel. The films were characterized by various techniques: Auger electron and X-ray photoelectron spectroscopies, Rutherford backscattering, transmission electron diffraction and X-ray diffraction. Mechanical properties such as stress, adhesion, friction coefficient and wear resistance were obtained by carrying measurements of the curvature of the silicon substrate, pull tests, and ball-on-disk tests, respectively.

This report contains documentation for improvements in a model for predicting the volume of gas bubble retention based on changes in waste level for high-level waste tanks at the Savannah River Site.

Dense arrays of high-aspect-ratio silicon microcolumns and microcones are formed by cumulative nanosecond pulsed excimer laser irradiation of single-crystal silicon in oxidizing atmospheres such as air and SF₆. Growth of such surface microstructures requires a redeposition model and also involves elements of self-organization. The shape of the microstructures, i.e. straight columns vs steeply sloping cones and connecting walls, is governed by the type and concentration of the oxidizing species, e.g. oxygen vs fluorine. Growth is believed to occur by a �catalyst-free� VLS (vapor-liquid-solid) mechanism that involves repetitive melting of the tips of the columns/cones and deposition there of the ablated flux of Si-containing vapor. Results are presented of a new investigation of how such different final microstructures as microcolumns or microcones joined by walls nucleate and develop. The changes in silicon surface morphology were systematically determined and compared as the number of pulsed KrF (248 nm) laser shots was increased from 25 to several thousand in both air and SF₆. The experiments in air and SF₆ reveal significant differences in initial surface cracking and pattern formation. Consequently, local protrusions are first produced and column or cone/wall growth is initiated by different processes and at different rates. Differences in the spatial …

This report contains analytical data for samples taken during Second Quarter 1999 from wells of the LFW series located at the Sanitary Landfill at the Savannah River Site. The data are submitted in reference to the Sanitary Landfill Operating Permit. The report presents monitoring results that equaled or exceeded the Safe Drinking Water Act final Primary Drinking Water Standards or screening levels, established by the US Environmental Protection Agency, the South Carolina final Primary Drinking Water Standard for lead, or the SRS flagging criteria.

As a result of the end of the Cold War, approximately 50 metric tons of plutonium are no longer needed and have been identified for disposition. A ceramic waste form is the chosen option for immobilization of the excess plutonium. The plutonium ceramic form then will be encased in high-level waste glass using can-in-canister technology for final disposition. The precursor materials are the non-radioactive components that are added to the plutonium feed stream to form the desired phases in the immobilization product. The precursor materials are blended and calcined prior to being mixed with the plutonium feed stream. The purpose of the calcine step is to remove any physical or chemical water retained in the precursors and convert any hydroxides or carbonates to the oxides. Initially, a temperature of 750 degrees C for a period of one hour was chosen for the calcining of the precursors. In this effort, several different calcine temperatures were investigated to evaluate the effect on initial phase formation (in the calcined precursors), thermal expansion of the pressed pellets during heating, and mineralogy and porosity of the final product.

During the first two years of radioactive operation of the Defense Waste Processing Facility process, several areas for improvement in melter design were identified. Due to the need for a process that allows continuous melter operation, the down time associated with disruption to melter operation and pouring has significant cost impact. A major objective of this task is to address performance limitations and deficiencies identified by the user.

We construct intersecting brane configurations in Anti-de-Sitter space localizing gravity to the intersection region, with any number n of extra dimensions. This allows us to construct two kinds of theories with infinitely large new dimensions, TeV scale quantum gravity and sub-millimeter deviations from Newton's Law. The effective 4D Planck scale M{sub Pl} is determined in terms of the fundamental Planck scale M{sub *} and the AdS radius of curvature L via the familiar relation M{sub Pl}{sup 2} {approx} M{sub *}{sup 2+n} L{sup n}; L acts as an effective radius of compactification for gravity on the intersection. Taking M{sub *} {approx} TeV and L {approx} sub-mm reproduces the phenomenology of theories with large extra dimensions. Alternately, taking M{sub *} {approx} L{sup -1} {approx} M{sub Pl}, and placing our 3-brane a distance {approx} 100M{sub Pl}{sup -1} away from the intersection gives us a theory with an exponential determination of the Weak/Planck hierarchy.

The report presents a thermal stability analysis of partially metallic particulate in two IWTS components, the knock out pot and settlers. Particulate in the knock out pot is thermally stable for combinations of average particle size and metal mass fraction which appear realistic. Particulate in the settlers is thermally stable when a realistic account of particle reactions over time, metal fraction, and size distribution is considered.

This sampling and analysis plan (SAP) identifies the type, quantity, and quality of data needed to support characterization of the sludge that remains in Tank 241-2-361. The procedures described in this SAP are based on the results of the 241-2-361 Sludge Characterization Data Quality Objectives (DQO) (BWHC 1999) process for the tank. The primary objectives of this project are to evaluate the contents of Tank 241-2-361 in order to resolve safety and safeguards issues and to assess alternatives for sludge removal and disposal.

This document summarizes the results of the U.S. Department of Energy's Near-Facility Environmental Monitoring program conducted by Waste Management Federal Services of Hanford, Inc. for Fluor Daniel Hanford, Inc. for 1998 in the 100,200/600, and 300/400 Areas of the Hanford Site, in southcentral Washington State. Surveillance activities included sampling and analyses of ambient air, surface water, groundwater, soil, sediments, and biota. Also, external radiation measurements and radiological surveys were taken at waste disposal sites, radiologically controlled areas, and roads. These activities were conducted to assess and control the effects of nuclear facilities and waste sites on the local environment. In addition, diffuse sources were monitored to determine compliance with federal, state, and/or local regulations. In general, although effects from nuclear facilities can still be observed on the Hanford Site and radiation levels are slightly elevated when compared to offsite locations, the differences are less than in previous years.

This Corrective Action Investigation Plan contains the US Department of Energy, Nevada Operations Office's approach to collect the data necessary to evaluate corrective action alternatives appropriate for the closure of Corrective Action Unit (CAU) 254 under the Federal Facility Agreement and Consent Order. Corrective Action Unit 254 consists of Corrective Action Site (CAS) 25-23-06, Decontamination Facility. Located in Area 25 at the Nevada Test Site (NTS), CAU 254 was used between 1963 through 1973 for the decontamination of test-car hardware and tooling used in the Nuclear Rocket Development Station program. The CAS is composed of a fenced area measuring approximately 119 feet by 158 feet that includes Building 3126, an associated aboveground storage tank, a potential underground storage area, two concrete decontamination pads, a generator, two sumps, and a storage yard. Based on site history, the scope of this plan is to resolve the problem statement identified during the Data Quality Objectives process that decontamination activities at this CAU site may have resulted in the release of contaminants of concern (COCs) onto building surfaces, down building drains to associated leachfields, and to soils associated with two concrete decontamination pads located outside the building. Therefore, the scope of the corrective action …

The S{sup 4}Z Model (''sub-site-scale saturated zone'') is a 3-D TOUGH2 model that was developed to study the saturated zone (SZ) at Yucca Mountain, Nevada, and to aid in the design and analysis of hydrologic tests. Yucca Mountain is the proposed site for a nuclear waste repository for the United States. The model covers an area of approximately 100 km{sup 2} around Yucca Mountain, as shown in Figure 1. The proposed repository is located in the unsaturated zone, immediately above the area of equidimensional gridblocks east of Solitario Canyon fault, which defines the crest of Yucca Mountain. The finely discretized region near the center of the domain corresponds to the area near a cluster of boreholes used for hydraulic and tracer testing. This discretization facilitates simulation of tests conducted there. The hydrogeologic structure beneath the mountain is comprised of dipping geologic units of variable thickness which are offset by faults. One of the primary objectives of the S{sup 4}Z modeling effort is to study the potential effects of the faulted structure on flow. Therefore, replication of the geologic structure in the model mesh is necessary. This paper summarizes (1) the mesh discretization used to capture the faulted geologic structure, and …

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It is well known that the attenuation of X-rays as they pass through a material can be used to quantify the amount of matter in their path. This is the basis for the gamma ray densitometer which can measure the amount of material on a moving conveyor belt. It is also the rationale for using X-rays for medical imaging as the attenuation can discriminate between tissue of different density and composition, yielding images of great diagnostic utility. Spatial resolution is obviously important with regard to detecting small features. However, it is less obvious that it plays an important role in obtaining quantitative information from the X-ray transmission data since the spatial resolution of the instrument can affect the accuracy of those measurements. This problem is particularly severe in the case of computed tomography where the accuracy of the reconstruction is dependent on the accuracy of the initial projection data. It should be noted that spatial resolution is not a concern for the case where the material is uniform. Here uniform is defined by small variations related to either the scale size of the resolution element in the detector, or to the size of a collimated X-ray beam. However, if the …

On July 28-29, 1999, the Federal Energy Technology Center (FETC) and the WMAC Foundation co-sponsored the Appalachian Rivers II Conference in Morgantown, West Virginia. This meeting brought together over 100 manufacturers, researchers, academicians, government agency representatives, watershed stewards, and administrators to examine technologies related to watershed assessment, monitoring, and restoration. Sessions included presentations and panel discussions concerning watershed analysis and modeling, decision-making considerations, and emerging technologies. The final session examined remediation and mitigation technologies to expedite the preservation of watershed ecosystems.

Within the next few decades, several million tons of scrap materials (such as metals or concrete) are expected to be removed from nuclear facilities across the world as a result of decontamination and decommissioning activities. Although much of the materials are expected to be free of radioactive contents, some will contain above-background concentrations of residual radioactive material. In many cases, materials containing or potentially containing above-background residual radioactive material have been disposed through burial at licensed facilities. However, some of the materials may be in the form of expensive equipment or devices that are still useful, and the incentive to recover them is high. Others may be expensive raw materials such as nickel, copper, or high-quality stainless steel that can easily be recovered by recycling. Yet another category, which includes carbon steel or concrete, is bulky and requires considerable space for burial. Although the value of these latter materials may not be significant, disposition options such as recycling present an attractive option for alleviating the limited burial capacity and the ever-increasing disposal costs at licensed burial facilities.

We report a new measurement of A{sub b} using data obtained by SLD in 1997-98. This measurement uses a vertex tag technique, where the selection of a b hemisphere is based on the reconstructed mass of the bottom hadron decay vertex. The method uses the 3D vertexing capabilities of SLD's CCD vertex detector and the small and stable SLC beams to obtain a high b-event tagging efficiency and purity of 78% and 97%, respectively. Charged kaons identified by the CRID detector provide an efficient quark-antiquark tag, with the analyzing power calibrated from the data. We obtain a preliminary result of A{sub b} = 0.997 {+-} 0.044 {+-} 0.067.

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The subject of this report is chemistry and engineering for the application of heterogeneous photocatalysts. The state of the art in catalysts are forms of titanium dioxide or modifications thereof, but work on other heterogeneous catalysts is included.

We have performed a series of laboratory experiments on saturated sand-clay mixtures. Measurements include frequency-dependent electrical properties using the four-electrode technique (10 mHz to 1 MHz), permeability, porosity, and acoustic velocities. We mixed clean quartz sand with Na-montmorillonite in a number of different configurations containing 0 to 10% clay: as a dispersed mixture, as discrete clay clusters, and arranged in distinct layers. Solutions of CaCl{sub 2} ranging from 0.0005 N to 0.75 N (0.05 to 64 mS/cm) and deionized water were used as saturating fluids. We found the electrical properties to be dependent on clay content, fluid conductivity, and microstructure in a complex fashion. Increasing fluid conductivity and increasing clay content generally resulted in higher electrical conductivity. For an individual sample, two main regions of conduction exist: a region dominated by surface conduction and a region where the ionic strength of the saturating fluid controlled conduction. The sample geometry (dispersed, non-dispersed, or layered clay configuration) was found to greatly affect the magnitude of the surface conductance in the range of low fluid conductivity.

This paper is intended as an introduction to some of the control challenges faced by developers of high penetration wind-diesel systems, with a focus on the management of power flows in order to achieve precise regulation of frequency and voltage in the face of rapidly varying wind power input and load conditions. The control algorithms presented herein are being implemented in the National Renewable Energy Laboratory (NREL) high penetration wind-diesel system controller that will be installed in the village of Wales, Alaska, in early 2000.

The mechanism of growth step generation from the edges of faceted crystals obtained from experimental results with KDP crystals is described. It shows that growth from the crystal edges is initiated by the deviation of the edges from their crystallographic orientation and formation of incomplete shapes of singular facets. The conditions for formation of the incomplete faceted shapes during dislocation growth are considered. It is shown that the process of step generation from the edges is determined by the mutual positions of the vicinal slopes on the adjacent faces.

A statement of record issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO discussed the federal government's efforts to implement total quality management initiatives."