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Soil aggregate stabilization and carbon sequestration: Feedbacks through organomineral associations

Description: Primary production (specifically, the rate and quality of C transfer below ground) and soil microbial activity (specifically, the rates of C transformation and decay) are recognized as the overall biological processes governing soil organic C (SOC) dynamics. These two processes and, hence, SOC cycling and storage are controlled by complex underlying biotic and abiotic interactions and feedbacks, most of which can be tied in one way or another to the influences of the five state factors related to soil formation, and many of which are sensitive to management practices. Overall, C input rates and quality are largely dependent on climate (especially temperature and precipitation), vegetation type and landscape, soil type, and management practices. Decomposition processes and turnover rates, however, are greatly influenced by climate, the type and quality of organic matter (e.g., N content and the ratios of C:N and lignin:N), chemical or physicochemical associations of organic matter (OM) with soil mineral components, and the location of OM within the soil.
Date: December 31, 1996
Creator: Jastrow, J.D. & Miller, R.M.
Partner: UNT Libraries Government Documents Department

Hanford tanks initiative work plan -- subsurface characterization to support the closure-readiness demonstration for tank 241-AX-104

Description: This document presents a plan for subsurface investigation near 241-AX-104 Single-Shell tank. Objectives of the investigation are soil sampling and analyses (physical and chemical), local stratigraphic correlation, groundwater background characterization, and geophysical surveys. The primary purpose of the investigation is to supply physical and hydraulic properties for numerical modeling of vadose zone flow and transport.
Date: September 27, 1996
Creator: Barnett, D.B.
Partner: UNT Libraries Government Documents Department

Common causes of material degradation in buried piping

Description: Buried pipe may fail for innumerable reasons. Causes can be mechanical damage/breakage, chemically initiated corrosion, or a combination. Failures may originate either internally or externally on the pipe. They may be related to flaws in the design, to excessive or unanticipated internal pressure or ground level loading, and/or to poor or uncertain installation practice. Or the pipe may simply ``wear out`` in service. Steel is strong and very forgiving in underground applications, especially with regard to backfill. However, soil support developed through densification or compaction is critical for brittle concrete and vitrified clay tile pipe, and is very important for cast iron and plastic pipe. Chemistry of the soil determines whether or not it will enhance corrosion or other types of degradation. Various causes and mechanisms for deterioration of buried pipe are indicated. Some peculiarities of the different materials of construction are characterized. Repair methods and means to circumvent special problems are described.
Date: January 20, 1997
Creator: Jenkins, C.F.
Partner: UNT Libraries Government Documents Department

Isotope tracers of organic carbon during artificial recharge

Description: This project developed an analytical technique for measuring the isotope abundance for 14C and 13C in total organic carbon (TOC) in order to test whether these measurements can trace TOC interaction with sedimentary material at the bottom of rivers and lakes, soils, and subsurface aquifer rocks.
Date: February 9, 1998
Creator: Davisson, M.L.
Partner: UNT Libraries Government Documents Department

Investigation of nonlinear dynamic soil property at the Savannah River Site

Description: This document summarizes laboratory dynamic soil testing investigations conducted by the University of Texas at Austin (UTA) for the Savannah River Site (SRS) (Stokoe et al., 1995a, Stokoe et al., 1995b, Sponseller and Stokoe, 1995). The purpose of the investigation is to provide an evaluation of past testing results in the context of new test data and the development of consistent site wide models of material strain dependencies based upon geologic formation, depth, and relevant index properties.
Date: January 17, 2000
Creator: Lee, R.C.
Partner: UNT Libraries Government Documents Department


Description: The global distribution of the radioactive elements (U, K, Th) at the lunar surface is an important parameter for an understanding of lunar evolution, because they have provided continuous heat over the lifetime of the Moon. Today, only the thorium distribution is available for the whole lunar surface [1]. Another key parameter that characterize the surface of the Moon is the presence of mare basalts. These basalts are concentrated on the nearside and are represented by materials with high-Fe content, sometimes associated with high-Ti. We demonstrated elsewhere that the fast neutron measurement made by Lunar Prospector is representative of the average soil atomic mass <A> [2]. <A> is primarily dominated by Fe and Ti in basaltic terranes, and therefore the map of the fast neutrons provides a good delineation of mare basalts. We focus here on the correlated variations of thorium abundances and fast neutron fluxes averaged over areas of 360 km in diameter, in an attempt to provide a better understanding of the thorium emplacement on the surface of the Moon.
Date: January 1, 2001
Partner: UNT Libraries Government Documents Department

Performance evaluation soil samples utilizing encapsulation technology

Description: Performance evaluation soil samples and method of their preparation are described using encapsulation technology to encapsulate analytes which are introduced into a soil matrix for analysis and evaluation by analytical laboratories. Target analytes are mixed in an appropriate solvent at predetermined concentrations. The mixture is emulsified in a solution of polymeric film forming material. The emulsified solution is polymerized to form microcapsules. The microcapsules are recovered, quantitated and introduced into a soil matrix in a predetermined ratio to form soil samples with the desired analyte concentration.
Date: December 1, 1997
Creator: Dahlgran, James R.
Partner: UNT Libraries Government Documents Department

F-Area Northeast Expansion Report, Volumes 1

Description: A geotechnical program has been complexed in F-Area at the Savannah River Site in South Carolina. This program investigated the subsurface conditions for the area known as the ''northeast expansion'' located in the F-Area.
Date: August 23, 1999
Creator: Syms, F.H.
Partner: UNT Libraries Government Documents Department

Chapter II.C Transport of Radionuclides through Soil and Ground Water

Description: The purpose of this report is to provide a clearer perspective of the impact of radionuclides in soil and groundwater, particularly for those not well-versed in soil science, hydrology, and geology. Through nuclear waste disposal or accidents, radionuclides come in contact with soil and groundwater. Man is exposed to radiation as a result of movement (or transport) of the radionuclides into his environment. Water is the principal carrier that induces transport, but chemical characteristics of soil inhibit the transport.
Date: December 23, 1980
Creator: Corey, J. C.
Partner: UNT Libraries Government Documents Department

Phase II Interim Report -- Assessment of Hydrocarbon Seepage Detection Methods on the Fort Peck Reservation, Northeast Montana

Description: The following work was performed: (1) collected reconnaissance micro-magnetic data and background field data for Area 1, (2) identified and collected soil sample data in three anomalous regions of Area 1, (3) sampled soils in Northwest Poplar Oil Field, (4) graphed, mapped, and interpreted all data areas listed above, (5) registered for the AAPG Penrose Conference on Hydrocarbon Seepage Mechanisms and Migration (postponed from 9/16/01 until 4/7/02 in Vancouver, B.C.). Results include the identification and confirmation of an oil and gas prospect in the northwest part of Area 1 and the verification of a potential shallow gas prospect in the West Poplar Area. Correlation of hydrocarbon micro-seepage to TM tonal anomalies needs further data analysis.
Date: April 24, 2002
Creator: Monson, Lawrence M.
Partner: UNT Libraries Government Documents Department


Description: The Leon Water Flood site has undergone one season of soil amendments and growth of specialized plants meant to colonize and accelerate the remediation of the salt-impacted site. The researchers characterized the impacted soil as to chemistry, added soil amendments, and planted several species of seedlings, and seeded the scarred areas. After the first growing season, the surface soil was again characterized and groundcover was also characterized. While plant growth was quite meager across the area, soil chemistry did improve over most of the two scars.
Date: November 26, 2001
Creator: Korphage, M. L.; Kindscher, Kelly & Langhus, Bruce G.
Partner: UNT Libraries Government Documents Department

Diagnosis and correction of soil nutrient limitations in intensively managed Southern pine forests. Quarterly report for the period January-March 2000

Description: This report is a summary of project status and activities performed during the quarter: (1) Initial error runs were finished and coding was adjusted to account for errors. A documentation manual and users manual have been written and gone through the first editing. The model was presented to the forest industry during a review meeting and adjustments were made to the model based on their input. The model has been sent to interested parties in Canada and Australia to test it and report back on any errors or modifications they feel would be necessary. (2) Based on the laboratory studies, one paper was written and submitted to the Soil and Water Science for internal review. It is currently under internal review. This paper describes a method for measuring resorption isotherms. A second paper that uses this method to investigate desorption isotherms for different soils is in progress. (3) All soil samples have been dried and sieved. All tissue samples have been ground and the ashing of the tissue samples has just begun. (4) A literature search continued focusing on root to shoot relationships of fast growing pine in order to assist the development of the nutrient demand section of the model. This is about 40% done.
Date: March 1, 2000
Creator: Comerford, N.B.
Partner: UNT Libraries Government Documents Department

An Approach to Industrial Stormwater Benchmarks: Establishing and Using Site-Specific Threshold Criteria at Lawrence Livermore National Laboratory

Description: Current regulatory schemes use generic or industrial sector specific benchmarks to evaluate the quality of industrial stormwater discharges. While benchmarks can be a useful tool for facility stormwater managers in evaluating the quality stormwater runoff, benchmarks typically do not take into account site-specific conditions, such as: soil chemistry, atmospheric deposition, seasonal changes in water source, and upstream land use. Failing to account for these factors may lead to unnecessary costs to trace a source of natural variation, or potentially missing a significant local water quality problem. Site-specific water quality thresholds, established upon the statistical evaluation of historic data take into account these factors, are a better tool for the direct evaluation of runoff quality, and a more cost-effective trigger to investigate anomalous results. Lawrence Livermore National Laboratory (LLNL), a federal facility, established stormwater monitoring programs to comply with the requirements of the industrial stormwater permit and Department of Energy orders, which require the evaluation of the impact of effluent discharges on the environment. LLNL recognized the need to create a tool to evaluate and manage stormwater quality that would allow analysts to identify trends in stormwater quality and recognize anomalous results so that trace-back and corrective actions could be initiated. LLNL created the site-specific water quality threshold tool to better understand the nature of the stormwater influent and effluent, to establish a technical basis for determining when facility operations might be impacting the quality of stormwater discharges, and to provide ''action levels'' to initiate follow-up to analytical results. The threshold criteria were based on a statistical analysis of the historic stormwater monitoring data and a review of relevant water quality objectives.
Date: September 7, 2006
Creator: Campbell, C G & Mathews, S
Partner: UNT Libraries Government Documents Department

Collboration: Interfacial Soil Chemistry of Radionuclides in the Unsaturated Zone

Description: The principal goal of this project was to assess the molecular nature and stability of radionuclide immoblization during weathering reactions in bulk Hanford sediments and their high surface area clay mineral constituents. We focused on the unique aqueous geochemical conditions that are representative of waste-impacted locations in the Hanford site vadose zone; high ionic strength, high pH and high Al concentrations. The specific objectives of the work were to measure the coupling of clay mineral weathering and contaminant uptake kinetics of Cs, Sr and I; determine the molecular structure of contaminant binding sites and their change with weathering time during and after exposure to synthetic tank waste leachate; establish the stability of neoformed weathering products and their sequestered contaminbants upon exposure of the solids to more natural soil solutaions afer remofal of the caustic waste source; and integrate macroscopic, microscopic and spectroscopic data to distinguish labile from non-labile contaminant binding environments, including their dependence on system composition and weathering time.
Date: December 11, 2006
Creator: Mueller, Karl T.; Chorover, Don; O'Day, Peggy; Serne, R. Jeff; Crosson, Garry; Bowers, Geoffrey et al.
Partner: UNT Libraries Government Documents Department

Ion exchange phenomena

Description: Ion exchange phenomena involve the population of readily exchangeable ions, the subset of adsorbed solutes that balance the intrinsic surface charge and can be readily replaced by major background electrolyte ions (Sposito, 2008). These phenomena have occupied a central place in soil chemistry research since Way (1850) first showed that potassium uptake by soils resulted in the release of an equal quantity of moles of charge of calcium and magnesium. Ion exchange phenomena are now routinely modeled in studies of soil formation (White et al., 2005), soil reclamation (Kopittke et al., 2006), soil fertilitization (Agbenin and Yakubu, 2006), colloidal dispersion/flocculation (Charlet and Tournassat, 2005), the mechanics of argillaceous media (Gajo and Loret, 2007), aquitard pore water chemistry (Tournassat et al., 2008), and groundwater (Timms and Hendry, 2007; McNab et al., 2009) and contaminant hydrology (Chatterjee et al., 2008; van Oploo et al., 2008; Serrano et al., 2009).
Date: May 1, 2011
Creator: Bourg, I.C. & Sposito, G.
Partner: UNT Libraries Government Documents Department

A suction lysimeter and a geophysical access port

Description: A sampling apparatus is described for monitoring vadose zones, geologic media or buried waste in sediment and more particularly to such an apparatus which is operable as an access port for geophysical logging and collecting fluid samples to permit analysis of such fluid samples for the presence of toxic substances, having a pipe-like, stainless steel, longitudinally extending, access tube with two ends, where the first end extends above the surface of the sediment and has a removable air tight seal. The subject invention further has a backing in fluid communication with the access tube and a fluid permeable plate contiguous with the backing, wherein the fluid permeable plate is made up of porous stainless steel. A reservoir is integrated into the second closed end of the access tube for containing the collected fluid. A vacuum pump, having a vacuum gauge/transducer attached thereto, is connected to the removable air tight seal for applying a vacuum to the access tube, such that gas and fluid samples may be drawn through the fluid permeable plate. A fluid sample connector coupled to the removable air tight seal, in addition to the vacuum pump with vacuum gauge/transducer, for withdrawing a fluid sample from the access tube.
Date: December 31, 1995
Creator: Hubbell, J.M. & Sisson, J.B.
Partner: UNT Libraries Government Documents Department

Regional biomass supply: three case studies in the Midwest, US

Description: Increased interest in the development and utilization of alternative energy sources has generated research demonstrating that fuels developed from energy crops (biofuels) can be a viable substitute for fossil fuels. A national energy program dedicated to the advancement of fuel derived from lignocellulosic crops could have major impacts on conventional energy supplied in the United States. Sufficient biofuel demand would allow conversion of croplands, as well as some pasture and forest lands, into biomass producing lands and possibly return to production acres formerly idled. A shift from crop, pasture or forest production activities to biomass production would likely require changes in the levels of inputs, outputs, and costs associated with these activities, which would impact producers and ultimately consumers. The conversion of cropland or idled land to biomass production will also have impacts on the physical characteristics of the soil. Soil erosion levels, soil chemical composition, soil structure, and organic matter content are some of the many soil attributes which will be impacted as a result of conversion. Research is needed to estimate the impact conversion activities have on these variables.
Date: June 1, 1995
Creator: English, B.C.; Dillivan, K.D.; Ojo, M.A.; Alexander, R.R. & Graham, R.L.
Partner: UNT Libraries Government Documents Department

Effects of acidic deposition on nutrient uptake, nutrient cycling and growth processes of vegetation in the spruce-fir ecosystem

Description: This report summarizes progress in three years of field research designed to evaluate biological and chemical indicators of the current and future health of the Southern Appalachian spruce-fir ecosystem. The emphasis of this research has been on the identification and understanding of mechanisms through which current levels of acidic deposition are impacting ecosystem processes. The identification of these principal mechanisms and key biological indicators of change was designed to improve our capabilities to detect, monitor, and assess the effects of air quality regulations and attendant future air quality changes on ecosystem response. Individual research tasks focused on the following research areas: (1) the significance of foliar uptake of atmospheric sources of nitrogen in relationship to plant utilization of N from available soil reserves; (2) linkages between atmospheric inputs to the soil surface, solution chemistry, and decomposition in the upper organic soil horizons; (3) effects of soil solution chemistry on uptake of cations and aluminum by fine roots; and (4) the effects of varying rates of calcium supply on carbon metabolism of Fraser fir and red spruce, and the relationship between calcium levels in wood cells and integrity of wood formed in bole and branches. Each of the individual tasks was designed to focus upon a mechanism or process that we consider critical to understanding chemical and biological linkages. These linkages will be important determinants in understanding the basis of past and potential future responses of the high elevation Southern Appalachian Forest to acidic deposition and other co-occurring environmental stresses. This report contains (1) background and rationale for the research undertaken in 1992-94; (2) a summary of principal research findings; (3) publications from this research; and (4) characterization of data sets produced by this research which will be the basis of future research, analyses and/or publications.
Date: October 16, 1996
Creator: McLaughlin, S. B.; Garten, C. T. & Wullschleger, S. D.
Partner: UNT Libraries Government Documents Department