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Production of hadrons and leptons at high p/sub t/ and pairs at high mass

Description: The experiment reported extends to higher beam energy the measurements of high-p/sub t/ particle production and high-mass pair production in N-N collisions, with improved resolution, particle identification, and luminosity. Besides addressing quantum chromodynamics issues, limits are set on the mass and lifetime of the axion. 25 refs., 19 figs. (LEW)
Date: January 1, 1986
Creator: Kaplan, D.M.
Partner: UNT Libraries Government Documents Department

Recommended Distribution Coefficients, Kd Values, for Special Analysis Risk Calculations Related to Waste Disposal and Tank Closure on the Savannah River Site

Description: The purpose of this document is to provide a technically defensible list of distribution coefficients, or Kd values, for use in performance assessment (PA) and special analysis (SA) calculations on the SRS. Only Kd values for radionuclides that have new information related to them or that have recently been recognized as being important are discussed in this report. Some 150 Kd values are provided in this report for various waste-disposal or tank-closure environments: soil, corrosion in grout, oxidizing grout waste, gravel, clay, and reducing concrete environments. Documentation and justification for the selection of each Kd value is provided.
Date: August 31, 2005
Creator: Kaplan, D
Partner: UNT Libraries Government Documents Department

Effects of Varying RedoxConditions on Natural Attenuation of Inorganic Contaminants from the D-Area Coal Pile Runoff Basin (U)

Description: The objective of this study was to provide geochemical parameters to characterize the D-Area Coal Pile Runoff Basin (DCPRB) sediment as a potential source term. It is anticipated that the measured values will be used in risk calculations and will provide additional technical support for imposing Monitored Natural Attenuation at D-Area. This study provides a detailed evaluation of the DCPRB sediment and is part of another study that quantified the Monitored Natural Attenuation of inorganic contaminants more broadly at the D-Area Expanded Operable Unit, which includes the DCPRB (Powell et al. 2004). Distribution coefficients (K{sub d} values; a solid to liquid contaminant concentration ratio) and the Potentially Leachable Fraction (the percent of the total contaminant concentration in the sediment that can likely contribute to a contaminant plume) were measured in a DCPRB sediment as a function of redox conditions. Redox conditions at the DCPRB are expected to vary greatly as the system undergoes varying drying and flooding conditions. Conservative values; K{sub d} values that err on the side of being too low and Potentially Leachable Fraction values that err on the side of being too high, are presented. The K{sub d} values are high compared to conservative literature values, and underscores the importance of measuring site-specific values to provide estimates of sediments natural attenuation/sorption capacities. The Potentially Leachable Fraction indicates that as little as 27% of the As, but all of the Cu and Tl will be part of the source term. In the case of the As, the remaining 83% will likely never leach out of the sediment, thereby providing a form of natural attenuation. Importantly, Be, Cr, Cu, Ni, and V concentrations in the sediment were less-than twice background levels, indicating this sediment was not a potential source for these contaminants. K{sub d} values generally increased significantly (As, ...
Date: May 30, 2004
Creator: Kaplan, D
Partner: UNT Libraries Government Documents Department

SUPPLEMENTAL ON-LINE MATERIAL, INFLUENCE OF pH ON PLUTONIUM DESORPTION/SOLUBILIZATION FROM SEDIMENT

Description: The oxidation state distribution of Pu in each sample for each reaction time was measured using a combined ultrafiltration and solvent extraction technique (1-4). First the oxidation state distribution of aqueous Pu is measured. Then the total system (solid and aqueous phase combined) Pu oxidation state distribution is measured by lowering the pH to leach Pu from the solid phase. For each reaction time, a 2.5-mL aliquot of the aqueous phase was removed and passed through a 12-nm filter (Microsep 30K MWCO Centrifugal Device; Pall Corporation, East Hills, NY). An aliquot of the filtrate was removed to determine the aqueous phase Pu concentration, and oxidation state distribution in the remaining filtrate was measured using the parallel solvent extraction technique discussed.
Date: March 8, 2006
Creator: Kaplan, D
Partner: UNT Libraries Government Documents Department

Geochemical Data Package for Performance Assessment Calculations Related to the Savannah River Site

Description: The Savannah River Site disposes of certain types of radioactive waste within subsurface-engineered facilities. One of the tools used to establish the capacity of a given site to safely store radioactive waste (i.e., that a site does not exceed its Waste Acceptance Criteria) is the Performance Assessment (PA). The objective of this document is to provide the geochemical values for the PA calculations. This work is being conducted as part of the on-going maintenance program that permits the PA to periodically update existing calculations when new data becomes available. Because application of values without full understanding of their original purpose may lead to misuse, this document also provides the geochemical conceptual model, approach used for selecting the values, the justification for selecting data, and the assumptions made to assure that the conceptual and numerical geochemical models are reasonably conservative (i.e., reflect conditions that will tend to predict the maximum risk to the hypothetical recipient). The geochemical parameters describe transport processes for 38 elements (>90 radioisotopes) potentially occurring within eight disposal units (Slit Trenches, Engineered Trenches, Low Activity Waste (LAW) Vault, Intermediate Level (ILV) Vaults, TRU-Pad-1, Naval Reactor Waste Pads, Components-in-Grout Trenches, and Saltstone Facility). This work builds upon well-documented work from previous PA calculations (McDowell-Boyer et al. 2000). The new geochemical concepts introduced in this data package are: (1) In the past, solubility products were used only in a few conditions (element existing in a specific environmental setting). This has been expanded to >100 conditions. (2) Radionuclide chemistry in cementitious environments is described through the use of both the Kd and apparent solubility concentration limit. Furthermore, the solid phase is assumed to age during the assessment period (thousands of years), resulting in three main types of controlling solid phases, each possessing a unique set of radionuclide sorption parameters (Kd and ...
Date: February 28, 2006
Creator: Kaplan, D
Partner: UNT Libraries Government Documents Department

Estimate of Gaseous 14Carbon Concentrations Emanating from the Intermediate-Level Vault Disposal Facility

Description: {sup 14}Carbon-bearing resin waste will be disposed in the Low-Activity Waste (LAW) Intermediate Level Vaults (ILV) located in E-Area on the Savannah River Site (SRS). This waste will be buried in a cementitious environment in the vadose zone, i.e., the subsurface zone above the aquifer. As the resin ages, and equilibrates with slowly infiltrating water, it is expected that the {sup 14}C will partition to the solid, liquid, and gaseous phases. The objective of this task was to estimate the concentration of gaseous {sup 14}C in the waste pore space that is in contact with the resin leachate. The approach used to estimate this value was built largely around data generated from lysimeter studies that were conducted for 9 years. These lysimeters contained the same type of used resins (mixed-bed deionizer resins used in the purification of the heavy water moderator of SRS reactors) as are being disposed in the ILV. During the 9 year period, pore water {sup 14}C leaching concentrations were monitored to provide an excellent estimate of the long-term behavior of {sup 14}C release rates from the resins. Thermodynamic calculations were conducted to calculate {sup 14}CO{sub 2(g)} concentrations. These calculations included the {sup 14}C pore water data from the lysimeter study, and data from a field study that was a natural analogue to a long-term cementitious environment (Khoury et al. 1992). The calculations predicted an extremely low {sup 14}CO{sub 2(g)} concentration of 1.9 x 10{sup -7} Ci/m{sup 3} {sup 14}CO{sub 2(g)} in the air spaces above the resin leachate. This low concentrations is not surprising in light of both laboratory and field observations that concrete acts as a strong sorbent of CO{sub 2(g)}. This calculated {sup 14}CO{sub 2(g)} concentration will now be included in future risk calculations.
Date: August 31, 2005
Creator: Kaplan, D
Partner: UNT Libraries Government Documents Department

DISTRIBUTION AND RANGE OF RADIONUCLIDE SORPTIOIN COEFFICIENTS IN A SAVANNAH RIVER SITE SUBSURFACE: STOCHASTIC MODELING CONSIDERATIONS - 10259

Description: The uncertainty associated with the sorption coefficient, or K{sub d} value, is one of the key uncertainties in estimating risk associated with burying low-level nuclear waste in the subsurface. The objective of this study was to measure >648 K{sub d} values and provide a measure of the range and distribution (normal or log-normal) of radionuclide K{sub d} values appropriate for the E-Area disposal site, within the Savannah River Site, near Aiken South Carolina. The 95% confidence level for the mean K{sub d} was twice the mean in the Aquifer Zone (18-30.5 m depth), equal to the mean for the Upper Vadose Zone (3.3-10 m depth), and half the mean for the Lower Vadose Zone (3.3-18 m depth). The distribution of K{sub d} values was log normal in the Upper Vadose Zone and Aquifer Zone, and normal in the Lower Vadose Zone. To our knowledge, this is the first report of natural radionuclide K{sub d} variability in the literature. Using ranges and distribution coefficients that are specific to the hydrostratigraphic unit improved model accuracy and reduced model uncertainty. Unfortunately, extension of these conclusions to other sites is likely not appropriate given that each site has its own sources of hydrogeological variability. However, this study provides one of the first examples of the development stochastic ranges and distributions of K{sub d} values for a hydrological unit for stochastic modeling.
Date: January 4, 2010
Creator: Kaplan, D.
Partner: UNT Libraries Government Documents Department

REVISED GUIDELINES FOR USING CELLULOSE DEGRADATION PRODUCT-IMPACTED KD VALUES FOR PERFORMANCE ASSESSMENTS AND COMPOSITE ANALYSES

Description: Cellulosic materials include wood, paper, rags, and cardboard products. These materials are co-disposed with radiological waste at the Savannah River Site's (SRS) E-Area Low-Level Waste Facility (ELLWF). Cellulosic materials readily degrade in the environment to form cellulose degradation products (CDP) that will partition to the sediment or remain mobile in the groundwater. Savannah River National Lab (SRNL) has conducted studies to estimate the impact of CDP on radionuclide sorption to SRS sediments (Kd values). It was found that CDP impact on radionuclide sorption varies with radionuclide and CDP concentration. Furthermore, it was found that the amount of carbon (C) in the system could increase or decrease Kd values with respect to the base case of when no CDP was added. Throughout the expected pH range of the ELLWF, a low concentration of CDP in the system would increase Kd values (because C would sorb to the sediment and provide more exchange sites for radionuclides to sorb), whereas greater concentrations of CDP ({ge}20 mg/L C) would decrease Kd values (because C would remain in solution and complex the radionuclide and not permit the radionuclide to sorb to the sediment). A review of >230 dissolved organic carbon (DOC) groundwater concentrations in the Old Radioactive Waste Burial Ground (ORWBG) at the SRS indicated that the average DOC concentration, a gross measure of CDP, was 5 mg/L C. At approximately this DOC concentration, the laboratory studies demonstrated that no anions (Tc, I, or Se) or cations (Ni, Sr, Ce, Eu, Zr, or Th) have decreased sorption in the presence of carbon (an analogue for CDP).
Date: May 14, 2012
Creator: Kaplan, D.
Partner: UNT Libraries Government Documents Department

NEPTUNIUM IV AND V SORPTIN TO END-MEMBER SUBSURFACE SEDIMENTS TO THE SAVANNAH RIVER SITE

Description: Migration of Np through the subsurface is expected to be primarily controlled by sorption to sediments. Therefore, understanding and quantifying Np sorption to sediments and sediments from the Savannah River Site (SRS) is vital to ensure safe disposal of Np bearing wastes. In this work, Np sorption to two sediments representing the geological extremes with respect to sorption properties expected in the SRS subsurface environment (named 'subsurface sandy sediment' and 'subsurface clayey sediment') was examined under a variety of conditions. First a series of baseline sorption tests at pH 5.5 under an oxic atmosphere was performed to understand Np sorption under typical subsurface conditions. These experiments indicated that the baseline K{sub d} values for the subsurface sandy and subsurface clayey sediments are 4.26 {+-} 0.24 L kg{sup -1} and 9.05 {+-} 0.61 L kg{sup -1}, respectively. These Np K{sub d} values of SRS sediments are the first to be reported since Sheppard et al. (1979). The previous values were 0.25 and 0.16 L kg{sup -1} for a low pH sandy sediment. To examine a possible range of K{sub d} values under various environmental scenarios, the effects of natural organic matter (NOM, also a surrogate for cellulose degradation products), the presence of various chemical reductants, and an anaerobic atmosphere on Np sorption were examined. The presence of NOM resulted in an increase in the Np K{sub d} values for both sediments. This behavior is hypothesized to be the result of formation of a ternary Np-NOM-sediment complex. Slight increases in the Np sorption (K{sub d} 13-24 L kg{sup -1}) were observed when performing experiments in the presence of chemical reductants (dithionite, ascorbic acid, zero-valent iron) or under anaerobic conditions. Presumably, the increased sorption can be attributed to a slight reduction of Np(V) to Np(IV), the stronger sorbing form of Np. The most ...
Date: November 13, 2009
Creator: Kaplan, D.
Partner: UNT Libraries Government Documents Department

RANGE AND DISTRIBUTION OF TECHNETIUM KD VALUES IN THE SRS SUBSURFACE ENVIRONMENT

Description: Performance assessments (PAs) are risk calculations used to estimate the amount of low-level radioactive waste that can be disposed at DOE sites. Distribution coefficients (K{sub d} values) are input parameters used in PA calculations to provide a measure of radionuclide sorption to sediment; the greater the K{sub d} value, the greater the sorption and the slower the estimated movement of the radionuclide through sediment. Understanding and quantifying K{sub d} value variability is important for estimating the uncertainty of PA calculations. Without this information, it is necessary to make overly conservative estimates about the possible limits of K{sub d} values, which in turn may increase disposal costs. Finally, technetium is commonly found to be amongst the radionuclides posing potential risk at waste disposal locations because it is believed to be highly mobile in its anionic form (pertechnetate, TcO{sub 4}{sup -}), it exists in relatively high concentrations in SRS waste, and it has a long half-life (213,000 years). The objectives of this laboratory study were to determine under SRS environmental conditions: (1) whether and to what extent TcO{sub 4}{sup -} sorbs to sediments, (2) the range of Tc K{sub d} values, (3) the distribution (normal or log-normal) of Tc K{sub d} values, and (4) how strongly Tc sorbs to SRS sediments through desorption experiments. Objective 3, to identify the Tc K{sub d} distribution is important because it provides a statistical description that influences stochastic modeling of estimated risk. The approach taken was to collect 26 sediments from a non-radioactive containing sediment core collected from E-Area, measure Tc K{sub d} values and then perform statistical analysis to describe the measured Tc K{sub d} values. The mean K{sub d} value was 3.4 {+-} 0.5 mL/g and ranged from -2.9 to 11.2 mL/g. The data did not have a Normal distribution (as defined by the ...
Date: October 28, 2008
Creator: Kaplan, D
Partner: UNT Libraries Government Documents Department

ESTIMATED NEPTUNIUM SEDIMENT SORPTION VALUES AS A FUNCTION OF PH AND MEASURED BARIUM AND RADIUM KD VALUES

Description: The objective of this document is to provide traceability and justification for a select few new geochemical data used in the Special Analysis entitled 'Special Analysis for the Dose Assessment of the Final Inventories in Center Slit Trenches One through Five'. Most values used in the Special Analysis came from the traditional geochemical data package, however, some recent laboratory measurements have made it possible to estimate barium K{sub d} values. Additionally, some recent calculations were made to estimate neptunium K{sub d} values as a function of pH. The assumptions, justifications, and calculations needed to generate these new values are presented in this document, and the values are summarized.
Date: January 13, 2011
Creator: Kaplan, D.
Partner: UNT Libraries Government Documents Department

Studies in theoretical particle physics

Description: This proposal focuses on research on three distinct areas of particle physics: (1) Nonperturbative QCD. I tend to continue work on analytic modelling of nonperturbative effects in the strong interactions. I have been investigating the theoretical connection between the nonrelativistic quark model and QCD. The primary motivation has been to understand the experimental observation of nonzero matrix elements involving current strange quarks in ordinary matter -- which in the quark model has no strange quark component. This has led to my present work on understanding constituent (quark model) quarks as collective excitations of QCD degrees of freedom. (2) Weak Scale Baryogenesis. A continuation of work on baryogenesis in the early universe from weak interactions. In particular, an investigation of baryogenesis occurring during the weak phase transition through anomalous baryon violating processes in the standard model of weak interactions. (3) Flavor and Compositeness. Further investigation of a new mechanism that I recently discovered for dynamical mass generation for fermions, which naturally leads to a family hierarchy structure. A discussion of recent past work is found in the next section, followed by an outline of the proposed research. A recent publication from each of these three areas is attached to this proposal.
Date: July 1, 1991
Creator: Kaplan, D.B.
Partner: UNT Libraries Government Documents Department

Estimated Duration of the Subsurface Reducing Environment Produced by the Z-Area Saltstone Disposal Facility

Description: The formula for saltstone includes approximately 25 per cent wt slag to create a reducing environment for mitigating the subsurface transport of a number of radionuclides, including technetium-99. Based on laboratory measurements and mass balance calculations, it was estimated that the Z-Area saltstone waste form will maintain a reducing environment for more than a thousand years and likely for more than 10,000 years. The calculations were very sensitive to infiltration flow rate, underscoring the importance of the proposed moisture barrier for mitigating contaminant transport. Laboratory measurements indicated that the slag used in the formulation of the saltstone has an exceptionally high reduction capacity. Furthermore, measurements of a subsurface SRS sediment indicated that it also had a significant reduction capacity, albeit almost an order of magnitude less than that of the slag. Approximately 78 percent of the reduction capacity in the disposal system came from the saltstone, 1 4 percent from the geological materials in the overlying moisture barrier, and 9 percent from the vault made from reducing grout. This version differs from the original (WSRC-RP-2003-00362, Rev. 0) in that additional text was added to further explain the assumptions of the calculations and some typographical errors were corrected.
Date: October 3, 2003
Creator: Kaplan, D.I.
Partner: UNT Libraries Government Documents Department

Enhanced Plutonium Mobility During Long-Term Transport Through an Unsaturated Subsurface Environment

Description: Plutonium moved more rapidly through vadose zone sediments than previous thought possible. Based on field studies conducted for up to 11 years and supplemental laboratory studies, it was hypothesized that periodic sediment drying caused the very slow release of tightly bound Pu into the mobile aqueous phase, presumably by oxidation of Pu(IV) to the more mobile Pu(V). Of particular interest, was that this release occurred in sediments, that when saturated with groundwater, promoted rapid reduction of Pu to the less mobile form, Pu(IV). Accurate prediction of Pu transport through the vadose zone is important because this region is expected to provide an important buffer between disposed nuclear waste and the biosphere.
Date: January 23, 2004
Creator: Kaplan, D.I.
Partner: UNT Libraries Government Documents Department

Reduction of Contaminant Mobility at the TNX Outfall Delta Through the Use of Apatite and Zero-Valent Iron as Soil Amendments

Description: The TNX pilot-scale research facility released processed waste, containing high concentrations of several metals and radionuclides into an unlined seepage basin between 1958 and 1980. The contents of this basin have entered the nearby swamp, the TNX Outfall Delta (TNX OD), by subsurface and overland flow. A multi-faceted strategy has been proposed recently for mitigating contaminant migration at the site. The intent of this remediation strategy is not only to minimize contaminant leaching in a cost-effective manner, but also to minimize harm to the sensitive TNX wetland ecosystem.
Date: December 18, 2002
Creator: Kaplan, D.
Partner: UNT Libraries Government Documents Department

Estimated Duration of the Subsurface Reducing Environment Produced by the Z-Area Saltstone Disposal Facility

Description: The formula for saltstone includes approximately 25 percent wt slag to create a reducing environment for mitigating the subsurface transport of a number of radionuclides, including technetium-99. Based on laboratory measurements and mass balance calculations, it was estimated that the Z-Area saltstone waste form will maintain a reducing environment for more than a thousand years and likely for more than 10,000 years. The calculations were very sensitive to infiltration flow rate, underscoring the importance of the proposed moisture barrier for mitigating contaminant transport. Laboratory measurements indicated that the slag used in the formulation of the saltstone has an exceptionally high reduction capacity. Furthermore, measurements of a subsurface SRS sediment indicated that it also had a significant reduction capacity, albeit almost an order of magnitude less than that of the slag. Approximately 78 percent of the reduction capacity in the disposal system came from the saltstone, 14 percent from the geological materials in the overlying moisture barrier, and 9 percent from the vault made from reducing grout.
Date: October 9, 2003
Creator: Kaplan, D.I.
Partner: UNT Libraries Government Documents Department

In-situ Kd values and geochemical behavior for inorganic and organic constituents of concern at the TNX Outfall Delta

Description: A series of tests were conducted to provide site-specific Kd values for constituents of concern at the TNX Outfall Delta Operable Unit. These Kd values can be used to calculate contaminant migration within the operable unit and are, at this time considered to be the most defensible values.
Date: February 11, 2000
Creator: Kaplan, D.I.
Partner: UNT Libraries Government Documents Department

Mercury speciation modeling using site specific chemical and redox data from the TNXOD OU

Description: The objective of this study was to evaluate mercury speciation under reducing conditions expected in sediments at the TNX Outfall Delta Operable Unit. These changes in speciation would then be used to infer whether mercury toxicity and mobility would be expected to be significantly altered under reducing conditions. The results from this work suggest that mercury would likely become more strongly retained by the solid phase under reducing conditions than under oxidizing conditions at the TNX Outfall Delta Site. Considering that experimental results indicate that mercury is extremely tightly bound to the solid phase under oxidizing conditions, little mercury mobility would therefore be expected under reducing conditions.
Date: March 22, 2000
Creator: Kaplan, D.I.
Partner: UNT Libraries Government Documents Department

Mixing of Process Heels, Process Solutions and Recycle Streams: Small-Scale Simulant

Description: The overall objective of this small-scale simulant mixing study was to identify the processes within the Hanford Site River Protection Project-Waste Treatment Plant (RPP-WTP) that may generate precipitates and to identify the types of precipitates formed. This information can be used to identify where mixtures of various solutions will cause precipitation of solids, potentially causing operational problems such as fouling equipment or increasing the amount of High Level Waste glass produced. Having this information will help guide protocols for flushing or draining tanks, mixing internal recycle streams, and mixing waste tank supernates. This report contains the discussion and thermodynamic chemical speciation modeling of the raw data.
Date: July 26, 2001
Creator: Kaplan, D.I.
Partner: UNT Libraries Government Documents Department

Proof-of-Concept of the Phytoimmobilization Technology for TNX Outfall Delta: Final Report

Description: A series of proof-of-principle studies was initiated to evaluate the soil remediation technology, phytoimmobilization, for application at the TNX Outfall Delta (TNX OD) operable unit. Phytoimmobilization involves two steps. The first step is entitled phytoextraction, and it takes place mostly during the spring and summer. During this step the plants extract contaminants from the sediment into the roots and then translocate the contaminants to the aboveground plant parts. The second step is referred to as sequestration and it takes place largely during the autumn and winter when annual plants senesce or deciduous trees drop their leaves. This step involves the immobilization of the contaminant once it leaches form the fallen leaves into a ''geomat,'' a geotextile embedded with mineral sequestering agents. This final report describes the results to date, including those reported in the status report (Kaplan et al. 2000a), those completed since the report was issued, and the preliminary calculations of the phytoimmobilization effectiveness.
Date: June 4, 2001
Creator: Kaplan, D.I.
Partner: UNT Libraries Government Documents Department

Milestone M4900: Simulant Mixing Analytical Results

Description: This report addresses Milestone M4900, ''Simulant Mixing Sample Analysis Results,'' and contains the data generated during the ''Mixing of Process Heels, Process Solutions, and Recycle Streams: Small-Scale Simulant'' task. The Task Technical and Quality Assurance Plan for this task is BNF-003-98-0079A. A report with a narrative description and discussion of the data will be issued separately.
Date: July 26, 2001
Creator: Kaplan, D.I.
Partner: UNT Libraries Government Documents Department

QCD and hadron structure

Description: I give a brief and selective overview of QCD as it pertains to determining hadron structure, and the relevant directions in this field for nuclear theory. This document is intended to start discussion about priorities, not end it.
Date: June 1, 1995
Creator: Kaplan, D.B.
Partner: UNT Libraries Government Documents Department

Influence of Sediment Redox Conditions on Contaminant Stabilization by Apatite and FE(0)

Description: Efficacy of stabilizing Ce, Co, and Pb by adding apatite and zero-valent Fe (Fe(0)) to contaminated wetland sediments was quantified under oxidizing and reducing conditions. The redox status and the general water chemistry of the oxidized and reduced treatments differed greatly, yet the influences of the amendments on contaminant stabilization were quite similar; both amendments significantly (p less than or equal to 0.05) reduced aqueous contaminant concentrations. Based on resin sorption studies and thermodynamic calculations, Ce existed primarily as cationic and to a smaller extent, anionic species, and Co existed almost as cationic, neutral, and organically complexed species. Based on a series of varying selective extractions, almost 50 wt-percentage of the Co and Pb were already strongly bound to the sediment, thereby limiting the potential (and need) of affecting additional immobilization through the use of amendments.
Date: May 17, 2004
Creator: KAPLAN, D.I.
Partner: UNT Libraries Government Documents Department