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Precipitate Formation Potential of Resin Regeneration Effluent in the 100-HR-3 Operable Unit

Description: Calculations performed as part of this study indicate that injection of treated groundwater containing treated regenerant solution has a high potential for precipitate formation that could lead to plugging of formation porosity surrounding the injection well. In the worst case scenario, substantial plugging could occur within a year of the initiation of injection. Some uncertainty is associated with respect to this conclusion. The uncertainty results from the fact that equilibrium with the most stable mineral assemblage cannot always be assumed and that slow precipitation rates could occur and reliable estimates of precipitation kinetics under Hanford aquifer conditions are not available. It is recommended that the potential of calcium phosphate precipitation be investigated further using a combination of laboratory and field investigations.
Date: October 9, 2009
Creator: Cantrell, Kirk J.
Partner: UNT Libraries Government Documents Department

Transuranic Contamination in Sediment and Groundwater at the U.S. DOE Hanford Site

Description: A review of transuranic radionuclide contamination in sediments and groundwater at the DOE’s Hanford Site was conducted. The review focused primarily on plutonium-239/240 and americium-241; however, other transuranic nuclides were discussed as well, including neptunium-237, plutonium-238, and plutonium-241. The scope of the review included liquid process wastes intentionally disposed to constructed waste disposal facilities such as trenches and cribs, burial grounds, and unplanned releases to the ground surface. The review did not include liquid wastes disposed to tanks or solid wastes disposed to burial grounds. It is estimated that over 11,800 Ci of plutonium-239, 28,700 Ci of americium-241, and 55 Ci of neptunium-237 have been disposed as liquid waste to the near surface environment at the Hanford Site. Despite the very large quantities of transuranic contaminants disposed to the vadose zone at Hanford, only minuscule amounts have entered the groundwater. Currently, no wells onsite exceed the DOE derived concentration guide for plutonium-239/240 (30 pCi/L) or any other transuranic contaminant in filtered samples. The DOE derived concentration guide was exceeded by a small fraction in unfiltered samples from one well (299-E28-23) in recent years (35.4 and 40.4 pCi/L in FY 2006). The primary reason that disposal of these large quantities of transuranic radionuclides directly to the vadose zone at the Hanford Site has not resulted in widespread groundwater contamination is that under the typical oxidizing and neutral to slightly alkaline pH conditions of the Hanford vadose zone, transuranic radionuclides (plutonium and americium in particular) have a very low solubility and high affinity for surface adsorption to mineral surfaces common within the Hanford vadose zone. Other important factors are the fact that the vadose zone is typically very thick (hundreds of feet) and the net infiltration rate is very low due to the desert climate. In some cases where transuranic radionuclides have ...
Date: August 20, 2009
Creator: Cantrell, Kirk J.
Partner: UNT Libraries Government Documents Department

Subsurface Behavior of Plutonium and Americium at Non-Hanford Sites and Relevance to Hanford

Description: Seven sites where Pu release to the environment has raised significant environmental concerns have been reviewed. A summary of the most significant hydrologic and geochemical features, contaminant release events and transport processes relevant to Pu migration at the seven sites is presented.
Date: February 1, 2008
Creator: Cantrell, Kirk J. & Riley, Robert G.
Partner: UNT Libraries Government Documents Department

Secondary Waste Form Down Selection Data Package – Ceramicrete

Description: As part of high-level waste pretreatment and immobilized low activity waste processing, liquid secondary wastes will be generated that will be transferred to the Effluent Treatment Facility on the Hanford Site for further treatment. These liquid secondary wastes will be converted to stable solid waste forms that will be disposed in the Integrated Disposal Facility. Currently, four waste forms are being considered for stabilization and solidification of the liquid secondary wastes. These waste forms are Cast Stone, Ceramicrete, DuraLith, and Fluidized Bed Steam Reformer. The preferred alternative will be down selected from these four waste forms. Pacific Northwest National Laboratory is developing data packages to support the down selection process. The objective of the data packages is to identify, evaluate, and summarize the existing information on the four waste forms being considered for stabilization and solidification of the liquid secondary wastes. The information included will be based on information available in the open literature and from data obtained from testing currently underway. This data package is for the Ceramicrete waste form. Ceramicrete is a relatively new engineering material developed at Argonne National Laboratory to treat radioactive and hazardous waste streams (e.g., Wagh 2004; Wagh et al. 1999a, 2003; Singh et al. 2000). This cement-like waste form can be used to treat solids, liquids, and sludges by chemical immobilization, microencapsulation, and/or macroencapsulation. The Ceramicrete technology is based on chemical reaction between phosphate anions and metal cations to form a strong, dense, durable, low porosity matrix that immobilizes hazardous and radioactive contaminants as insoluble phosphates and microencapsulates insoluble radioactive components and other constituents that do not form phosphates. Ceramicrete is a type of phosphate-bonded ceramic, which are also known as chemically bonded phosphate ceramics. The Ceramicrete binder is formed through an acid-base reaction between calcined magnesium oxide (MgO; a base) and potassium ...
Date: August 31, 2011
Creator: Cantrell, Kirk J. & Westsik, Joseph H.
Partner: UNT Libraries Government Documents Department

Plutonium and Americium Geochemistry at Hanford: A Site Wide Review

Description: This report was produced to provide a systematic review of the state-of-knowledge of plutonium and americium geochemistry at the Hanford Site. The report integrates existing knowledge of the subsurface migration behavior of plutonium and americium at the Hanford Site with available information in the scientific literature regarding the geochemistry of plutonium and americium in systems that are environmentally relevant to the Hanford Site. As a part of the report, key research needs are identified and prioritized, with the ultimate goal of developing a science-based capability to quantitatively assess risk at sites contaminated with plutonium and americium at the Hanford Site and the impact of remediation technologies and closure strategies.
Date: August 23, 2012
Creator: Cantrell, Kirk J. & Felmy, Andrew R.
Partner: UNT Libraries Government Documents Department

A Review of Subsurface Behavior of Plutonium and Americium at the 200-PW-1/3/6 Operable Units

Description: This report begins with a brief summary of the history and current status of 200-PW-1/3/6 OUs in section 2.0. This is followed by a description of our concentual model of Pu/Am migration at the 200-PW-1/3/6 OUs, during both past artificial recharge conditions and current natural recharge condictions (section 3.0). Section 4.0 discusses data gaps and information needs. The final section (section 5.0) provides recommendations for futher work to address the data gaps and information needs identified in section 4.0.
Date: January 31, 2008
Creator: Cantrell, Kirk J. & Riley, Robert G.
Partner: UNT Libraries Government Documents Department

Contaminant Release Data Package for Residual Waste in Single-Shell Hanford Tanks

Description: The Hanford Federal Facility Agreement and Consent Order requires that a Resource Conservation and Recovery Act (RCRA) Facility Investigation report be submitted to the Washington State Department of Ecology. The RCRA Facility Investigation report will provide a detailed description of the state of knowledge needed for tank farm performance assessments. This data package provides detailed technical information about contaminant release from closed single-shell tanks necessary to support the RCRA Facility Investigation report. It was prepared by Pacific Northwest National Laboratory (PNNL) for CH2M HILL Hanford Group, Inc., which is tasked by the U.S. Department of Energy (DOE) with tank closure. This data package is a compilation of contaminant release rate data for residual waste in the four Hanford single-shell tanks (SSTs) that have been tested (C-103, C-106, C-202, and C-203). The report describes the geochemical properties of the primary contaminants of interest from the perspective of long-term risk to groundwater (uranium, technetium-99, iodine-129, chromium, transuranics, and nitrate), the occurrence of these contaminants in the residual waste, release mechanisms from the solid waste to water infiltrating the tanks in the future, and the laboratory tests conducted to measure release rates.
Date: December 1, 2007
Creator: Deutsch, William J.; Cantrell, Kirk J. & Krupka, Kenneth M.
Partner: UNT Libraries Government Documents Department

Plutonium Mobility Studies: 216-Z-9 Trench Sample Analysis Results

Description: A variety of analyses were conducted on selected sediment samples collected from two wells (299 W15-46 and 299-W15-48) drilled near the 216-Z-9 Trench to elucidate the form and potential for Pu and Am to be mobilized under present conditions and those that could be expected in future remediation scenarios. Analyses included moisture content, determination of the less than sand size fraction (silt plus clay), carbon analysis, SEM/EDS analysis, microwave-assisted acid digestions for total element analysis, and extraction tests using Hanford groundwater as the leachate. Results of the extraction tests were used as input to conduct equilibrium geochemical modeling of the solutions with Geochemist’s Workbench®. Geochemical modeling results for Pu were evaluated in terms of recent conclusions regarding the solubility and redox reactions of Pu by Neck et al. (2007a, 2007b). It was found that the highest concentrations of Pu and Am were associated with sediments of low silt/clay content and occur above silt/clay rich layers within the sediment profile. It was also found that the Pu and Am were relatively enriched in the silt/clay portion of these samples. The fact that the highest concentrations of Pu and Am occurred in sediments with low silt/clay contents suggests that waste solutions had perched on top of the low permeability silt/clay rich layers and interactions with the high silt/clay layers was minimal. SEM/EDS analysis indicated that the Pu and Am in these sediments does not occur as discrete micron size particles, and therefore must occur as mononuclear or polynuclear/ nanoclusters size particles adsorbed throughout the sediment samples. Leaching of these samples with Hanford groundwater indicates that release of Pu and Am from the sediments is correlated most significantly with the acidity of the water and not the initial concentrations of Pu and Am in the sediments. Only extracts that were acidic after contact ...
Date: September 5, 2008
Creator: Cantrell, Kirk J.; Geiszler, Keith N. & Arey, Bruce W.
Partner: UNT Libraries Government Documents Department

Status Report on Transfer of Physical and Hydraulic Properties Databases to the Hanford Environmental Information System - PNNL Remediation Decision Support Project, Task 1, Activity 6

Description: This document provides a status report on efforts to transfer physical and hydraulic property data from PNNL to CHPRC for incorporation into HEIS. The Remediation Decision Support (RDS) Project is managed by Pacific Northwest National Laboratory (PNNL) to support Hanford Site waste management and remedial action decisions by the U.S. Department of Energy and their contractors. The objective of Task 1, Activity 6 of the RDS project is to compile all available physical and hydraulic property data for sediments from the Hanford Site, to port these data into the Hanford Environmental Information System (HEIS), and to make the data web-accessible to anyone on the Hanford Local Area Network via the so-called Virtual Library. These physical and hydraulic property data are used to estimate parameters for analytical and numerical flow and transport models that are used for site risk assessments and evaluation of remedial action alternatives. In past years efforts were made by RDS project staff to compile all available physical and hydraulic property data for Hanford sediments and to transfer these data into SoilVision{reg_sign}, a commercial geotechnical software package designed for storing, analyzing, and manipulating soils data. Although SoilVision{reg_sign} has proven to be useful, its access and use restrictions have been recognized as a limitation to the effective use of the physical and hydraulic property databases by the broader group of potential users involved in Hanford waste site issues. In order to make these data more widely available and useable, a decision was made to port them to HEIS and to make them web-accessible via a Virtual Library module. In FY08 the original objectives of this activity on the RDS project were to: (1) ensure traceability and defensibility of all physical and hydraulic property data currently residing in the SoilVision{reg_sign} database maintained by PNNL, (2) transfer the physical and hydraulic ...
Date: June 30, 2009
Creator: Rockhold, Mark L.; Middleton, Lisa A. & Cantrell, Kirk J.
Partner: UNT Libraries Government Documents Department

Selection and Traceability of Parameters To Support Hanford-Specific RESRAD Analyses -- Fiscal Year 2008 Status Report

Description: In fiscal years 2007 and 2008, the Hanford Site Groundwater Remediation Project, formerly managed by Fluor Hanford, Inc., requested the Pacific Northwest National Laboratory (PNNL) to support the development and initial implementation of a strategy to establish and maintain, under configuration control, a set of Hanford-specific flow and transport parameter estimates that can be used to support Hanford Site assessments. This document provides a summary of those efforts, culminating in a set of best-estimate Hanford-specific parameters for use in place of the default parameters used in the RESRAD code. The RESRAD code is a computer model designed to estimate radiation doses and risks from RESidual RADioactive materials. The long-term goals of the PNNL work are to improve the consistency, defensibility, and traceability of parameters and their ranges of variability, and to ensure a sound basis for assigning parameters for flow and transport models in the code. The strategy was to start by identifying the existing parameter data sets most recently used in site assessments, documenting these parameter data sets and the raw data sets on which they were based, and using the existing parameter sets to define best-estimate parameters for use in the RESRAD code. The Hanford-specific assessment parameters compiled for use in RESRAD are traceable back to the professional judgment of the authors of published documents. Within the references, parameters are often not directly traceable back to the raw data and analytical approaches used to derive the assessment parameters. Future activities will work to continuously improve the defensibility and traceability of the parameter data sets and to address limitations and technical issues associated with the existing assessment parameter data sets.
Date: July 24, 2009
Creator: Last, George V.; Rockhold, Mark L.; Murray, Christopher J. & Cantrell, Kirk J.
Partner: UNT Libraries Government Documents Department

Geochemical Characterization Data Package for the Vadose Zone in the Single-Shell Tank Waste Management Areas at the Hanford Site

Description: This data package discusses the geochemistry of vadose zone sediments beneath the single-shell tank (SST) farms at the U.S. Department of Energy’s (DOE’s) Hanford Site. The purpose of the report is to provide a review of the most recent and relevant geochemical information available for the vadose zone beneath the SST farms and the Integrated Disposal Facility (IDF).
Date: January 7, 2008
Creator: Cantrell, Kirk J.; Brown, Christopher F.; Serne, R. Jeffrey & Krupka, Kenneth M.
Partner: UNT Libraries Government Documents Department

Geochemical Implications of CO2 Leakage Associated with Geologic Storage: A Review

Description: Leakage from deep storage reservoirs is a major risk factor associated with geologic sequestration of carbon dioxide (CO2). Different scientific theories exist concerning the potential implications of such leakage for near-surface environments. The authors of this report reviewed the current literature on how CO2 leakage (from storage reservoirs) would likely impact the geochemistry of near surface environments such as potable water aquifers and the vadose zone. Experimental and modeling studies highlighted the potential for both beneficial (e.g., CO2 re sequestration or contaminant immobilization) and deleterious (e.g., contaminant mobilization) consequences of CO2 intrusion in these systems. Current knowledge gaps, including the role of CO2-induced changes in redox conditions, the influence of CO2 influx rate, gas composition, organic matter content and microorganisms are discussed in terms of their potential influence on pertinent geochemical processes and the potential for beneficial or deleterious outcomes. Geochemical modeling was used to systematically highlight why closing these knowledge gaps are pivotal. A framework for studying and assessing consequences associated with each factor is also presented in Section 5.6.
Date: July 9, 2012
Creator: Harvey, Omar R.; Qafoku, Nikolla; Cantrell, Kirk J. & Brown, Christopher F.
Partner: UNT Libraries Government Documents Department

Combined Estimation of Hydrogeologic Conceptual Model and Parameter Uncertainty

Description: The objective of the research described in this report is the development and application of a methodology for comprehensively assessing the hydrogeologic uncertainties involved in dose assessment, including uncertainties associated with conceptual models, parameters, and scenarios. This report describes and applies a statistical method to quantitatively estimate the combined uncertainty in model predictions arising from conceptual model and parameter uncertainties. The method relies on model averaging to combine the predictions of a set of alternative models. Implementation is driven by the available data. When there is minimal site-specific data the method can be carried out with prior parameter estimates based on generic data and subjective prior model probabilities. For sites with observations of system behavior (and optionally data characterizing model parameters), the method uses model calibration to update the prior parameter estimates and model probabilities based on the correspondence between model predictions and site observations. The set of model alternatives can contain both simplified and complex models, with the requirement that all models be based on the same set of data. The method was applied to the geostatistical modeling of air permeability at a fractured rock site. Seven alternative variogram models of log air permeability were considered to represent data from single-hole pneumatic injection tests in six boreholes at the site. Unbiased maximum likelihood estimates of variogram and drift parameters were obtained for each model. Standard information criteria provided an ambiguous ranking of the models, which would not justify selecting one of them and discarding all others as is commonly done in practice. Instead, some of the models were eliminated based on their negligibly small updated probabilities and the rest were used to project the measured log permeabilities by kriging onto a rock volume containing the six boreholes. These four projections, and associated kriging variances, were averaged using the posterior ...
Date: March 1, 2004
Creator: Meyer, Philip D.; Ye, Ming; Neuman, Shlomo P. & Cantrell, Kirk J.
Partner: UNT Libraries Government Documents Department

Decision Document for the Storm Water Outfalls/Industrial Wastewater Treatment Plant, Pesticide Rinse Area, Old Fire Fighting Training Pit, Illicit PCB Dump Site, and the Battery Acid Pit Fort Lewis, Washington

Description: PNNL conducted independent site evaluations for four sites at Fort Lewis, Washington, to determine their suitability for closure on behalf of the installation. These sites were recommended for "No Further Action" by previous invesitgators and included the Storm Water Outfalls/Industrial Waste Water Treatment Plant (IWTP), the Pesticide Rinse Area, the Old Fire Fighting Training Pit, and the Illicit PCB Dump Site.
Date: December 11, 2000
Creator: Cantrell, Kirk J.; Liikala, Terry L.; Strenge, Dennis L. & Taira, Randal Y.
Partner: UNT Libraries Government Documents Department

Thermodynamic Data for Geochemical Modeling of Carbonate Reactions Associated with CO2 Sequestration – Literature Review

Description: Permanent storage of anthropogenic CO2 in deep geologic formations is being considered as a means to reduce the concentration of atmospheric CO2 and thus its contribution to global climate change. To ensure safe and effective geologic sequestration, numerous studies have been completed of the extent to which the CO2 migrates within geologic formations and what physical and geochemical changes occur in these formations when CO2 is injected. Sophisticated, computerized reservoir simulations are used as part of field site and laboratory CO2 sequestration studies. These simulations use coupled multiphase flow-reactive chemical transport models and/or standalone (i.e., no coupled fluid transport) geochemical models to calculate gas solubility, aqueous complexation, reduction/oxidation (redox), and/or mineral solubility reactions related to CO2 injection and sequestration. Thermodynamic data are critical inputs to modeling geochemical processes. The adequacy of thermodynamic data for carbonate compounds has been identified as an important data requirement for the successful application of these geochemical reaction models to CO2 sequestration. A review of thermodynamic data for CO2 gas and carbonate aqueous species and minerals present in published data compilations and databases used in geochemical reaction models was therefore completed. Published studies that describe mineralogical analyses from CO2 sequestration field and natural analogue sites and laboratory studies were also reviewed to identify specific carbonate minerals that are important to CO2 sequestration reactions and therefore require thermodynamic data. The results of the literature review indicated that an extensive thermodynamic database exists for CO2 and CH4 gases, carbonate aqueous species, and carbonate minerals. Values of ∆fG298° and/or log Kr,298° are available for essentially all of these compounds. However, log Kr,T° or heat capacity values at temperatures above 298 K exist for less than approximately one-third of these compounds. Because the temperatures of host formations that will be used for CO2 injection and sequestration will be at tempera¬tures ...
Date: September 28, 2010
Creator: Krupka, Kenneth M.; Cantrell, Kirk J. & McGrail, B. Peter
Partner: UNT Libraries Government Documents Department

Decision Document for the Storm Water Outfalls/Industrial Wastewater Treatment Plant, Pesticide Rinse Area, Old Fire Fighting Training Pit, Illicit PCB Dump Site, and the Battery Acid Pit Fort Lewis, Washington

Description: PNNL conducted independent site evaluations for four sites at Fort Lewis, Washington, to determine their suitability for closure on behalf of the installation. These sites were recommended for ''No Further Action'' by previous investigators and included the Storm Water Outfalls/Industrial Waste Water Treatment Plant (IWTP), the Pesticide Rinse Area, the Old Fire Fighting Training Pit, and the Illicit PCB Dump Site.
Date: January 10, 2001
Creator: Cantrell, Kirk J; Liikala, Terry L; Strenge, Dennis L & Taira, Randal Y
Partner: UNT Libraries Government Documents Department

Characterization Activities Conducted at the 183-DR Site in Support of an In Situ Gaseous Reduction Demonstration

Description: In Situ Gaseous Reduction (ISGR) is a technology developed by DOE for the remediation of soil waste sites contaminated with hexavalent chromium. This document presents information associated with characterization activities conducted at the 183-DR site at Hanford, which is associated with a significant groundwater contaminant plume and was formerly a water treatment facility that utilized chromate as a corrosion inhibitor. Geotechnical and chemical data were collected during the excavation of trenches and the drilling of two vadose zone boreholes to support a possible ISGR demonstration at 183-DR. Although elevated total chromium and trace levels of hexavalent chromium were identified from one of the trenches and one of the boreholes, it appears that the boreholes missed the vadose zone contaminant source responsible for the chromium groundwater plume located downgradient of the 183-DR site. Recommendations are provided, however, for future work at 183-DR that may serve to identify the source for the groundwater plume and possibly provide an opportunity for an ISGR demonstration.
Date: March 30, 2001
Creator: Thornton, Edward C.; Gilmore, Tyler J.; Olsen, Khris B.; Schalla, Ronald & Cantrell, Kirk J.
Partner: UNT Libraries Government Documents Department

Geochemical Processes Data Package for the Vadose Zone in the Single-Shell Tank Waste Management Areas at the Hanford Site

Description: This data package discusses the geochemistry of vadose zone sediments beneath the single-shell tank farms at the U.S. Department of Energy’s (DOE’s) Hanford Site. The purpose of the report is to provide a review of the most recent and relevant geochemical process information available for the vadose zone beneath the single-shell tank farms and the Integrated Disposal Facility. Two companion reports to this one were recently published which discuss the geology of the farms (Reidel and Chamness 2007) and groundwater flow and contamination beneath the farms (Horton 2007).
Date: September 28, 2007
Creator: Cantrell, Kirk J.; Zachara, John M.; Dresel, P. Evan; Krupka, Kenneth M. & Serne, R. Jeffrey
Partner: UNT Libraries Government Documents Department

FY12 ARRA-NRAP Report – Studies to Support Risk Assessment of Geologic Carbon Sequestration

Description: This report summarizes results of research conducted during FY2012 to support the assessment of environmental risks associated with geologic carbon dioxide (CO2) sequestration and storage. Several research focus areas are ongoing as part of this project. This includes the quantification of the leachability of metals and organic compounds from representative CO2 storage reservoir and caprock materials, the fate of metals and organic compounds after release, and the development of a method to measure pH in situ under supercritical CO2 (scCO2) conditions. Metal leachability experiments were completed on 6 different rock samples in brine in equilibrium with scCO2 at representative geologic reservoir conditions. In general, the leaching of RCRA metals and other metals of concern was found to be limited and not likely to be a significant issue (at least, for the rocks tested). Metals leaching experiments were also completed on 1 rock sample with scCO2 containing oxygen at concentrations of 0, 1, 5, and 10% to simulate injection of CO2 originating from the oxy-fuel combustion process. Significant differences in the leaching behavior of certain metals were observed when oxygen is present in the CO2. These differences resulted from oxidation of sulfides, release of sulfate, ferric iron and other metals, and subsequent precipitation of iron oxides and some sulfates such as barite. Experiments to evaluate the potential for mobilization of organic compounds from representative reservoir materials and cap rock and their fate in porous media (quartz sand) have been conducted. Results with Fruitland coal and Gothic shale indicate that lighter organic compounds were more susceptible to mobilization by scCO2 compared to heavier compounds. Alkanes demonstrated very low extractability by scCO2. No significant differences were observed between the extractability of organic compounds by dry or water saturated scCO2. Reaction equilibrium appears to have been reached by 96 hours. When the scCO2 was ...
Date: September 27, 2011
Creator: Cantrell, Kirk J.; Shao, Hongbo; Thompson, C. J.; Zhong, Lirong; Jung, Hun Bok & Um, Wooyong
Partner: UNT Libraries Government Documents Department

Results of Aging Tests of Vendor-Produced Blended Feed Simulant

Description: The Hanford Tank Waste Treatment and Immobilization Plant (WTP) is procuring through Pacific Northwest National Laboratory (PNNL) a minimum of five 3,500 gallon batches of waste simulant for Phase 1 testing in the Pretreatment Engineering Platform (PEP). To make sure that the quality of the simulant is acceptable, the production method was scaled up starting from laboratory-prepared simulant through 15-gallon vendor prepared simulant and 250-gallon vendor prepared simulant before embarking on the production of the 3500-gallon simulant batch by the vendor. The 3500-gallon PEP simulant batches were packaged in 250-gallon high molecular weight polyethylene totes at NOAH Technologies. The simulant was stored in an environmentally controlled environment at NOAH Technologies within their warehouse before blending or shipping. For the 15-gallon, 250-gallon, and 3500-gallon batch 0, the simulant was shipped in ambient temperature trucks with shipment requiring nominally 3 days. The 3500-gallon batch 1 traveled in a 70-75°F temperature controlled truck. Typically the simulant was uploaded in a PEP receiving tank within 24-hours of receipt. The first uploading required longer with it stored outside. Physical and chemical characterization of the 250-gallon batch was necessary to determine the effect of aging on the simulant in transit from the vendor and in storage before its use in the PEP. Therefore, aging tests were conducted on the 250-gallon batch of the vendor-produced PEP blended feed simulant to identify and determine any changes to the physical characteristics of the simulant when in storage. The supernate was also chemically characterized. Four aging scenarios for the vendor-produced blended simulant were studied: 1) stored outside in a 250-gallon tote, 2) stored inside in a gallon plastic bottle, 3) stored inside in a well mixed 5-L tank, and 4) subject to extended temperature cycling under summer temperature conditions in a gallon plastic bottle. The following series of aging tests ...
Date: April 21, 2009
Creator: Russell, Renee L.; Buchmiller, William C.; Cantrell, Kirk J.; Peterson, Reid A. & Rinehart, Donald E.
Partner: UNT Libraries Government Documents Department

MinChem: A Prototype Petrologic Database for Hanford Site Sediments

Description: A prototype petrologic database (MinChem) has been under continual development for several years. MinChem contains petrologic, mineralogical, and bulk-rock geochemical data for Hanford Site sediments collected over multiple decades. The database is in relational form and consists of a series of related tables modeled after the Hanford Environmental Information System HEIS (BHI 2002) structures. The HEIS-compatible tables were created in anticipation of eventual migration into HEIS, or some future form of HEIS (e.g. HEIS-GEO). There are currently a total of 13,129 results in MinChem from 521 samples collected at 381 different sampling sites. These data come from 19 different original source documents published and unpublished (e.g. letter reports) between 1976 and 2009. The data in MinChem consist of results from analytical methods such as optical and electron microscopy, x-ray diffraction, x-ray fluorescence, and electron probe microanalysis.
Date: September 1, 2010
Creator: Mackley, Rob D.; Last, George V.; Serkowski, John A.; Middleton, Lisa A. & Cantrell, Kirk J.
Partner: UNT Libraries Government Documents Department

Combined Estimation of Hydrogeologic Conceptual Model, Parameter, and Scenario Uncertainty with Application to Uranium Transport at the Hanford Site 300 Area

Description: This report to the Nuclear Regulatory Commission (NRC) describes the development and application of a methodology to systematically and quantitatively assess predictive uncertainty in groundwater flow and transport modeling that considers the combined impact of hydrogeologic uncertainties associated with the conceptual-mathematical basis of a model, model parameters, and the scenario to which the model is applied. The methodology is based on a n extension of a Maximum Likelihood implementation of Bayesian Model Averaging. Model uncertainty is represented by postulating a discrete set of alternative conceptual models for a site with associated prior model probabilities that reflect a belief about the relative plausibility of each model based on its apparent consistency with available knowledge and data. Posterior model probabilities are computed and parameter uncertainty is estimated by calibrating each model to observed system behavior; prior parameter estimates are optionally included. Scenario uncertainty is represented as a discrete set of alternative future conditions affecting boundary conditions, source/sink terms, or other aspects of the models, with associated prior scenario probabilities. A joint assessment of uncertainty results from combining model predictions computed under each scenario using as weight the posterior model and prior scenario probabilities. The uncertainty methodology was applied to modeling of groundwater flow and uranium transport at the Hanford Site 300 Area. Eight alternative models representing uncertainty in the hydrogeologic and geochemical properties as well as the temporal variability were considered. Two scenarios represent alternative future behavior of the Columbia River adjacent to the site were considered. The scenario alternatives were implemented in the models through the boundary conditions. Results demonstrate the feasibility of applying a comprehensive uncertainty assessment to large-scale, detailed groundwater flow and transport modeling and illustrate the benefits of the methodology I providing better estimates of predictive uncertiay8, quantitative results for use in assessing risk, and an improved understanding ...
Date: July 30, 2007
Creator: Meyer, Philip D.; Ye, Ming; Rockhold, Mark L.; Neuman, Shlomo P. & Cantrell, Kirk J.
Partner: UNT Libraries Government Documents Department

Hanford Site Tank 241-C-108 Residual Waste Contaminant Release Models and Supporting Data

Description: This report presents the results of laboratory characterization, testing, and analysis for a composite sample (designated 20578) of residual waste collected from single-shell tank C-108 during the waste retrieval process after modified sluicing. These studies were completed to characterize concentration and form of contaminant of interest in the residual waste; assess the leachability of contaminants from the solids; and develop release models for contaminants of interest. Because modified sluicing did not achieve 99% removal of the waste, it is expected that additional retrieval processing will take place. As a result, the sample analyzed here is not expected to represent final retrieval sample.
Date: June 18, 2010
Creator: Cantrell, Kirk J.; Krupka, Kenneth M.; Geiszler, Keith N.; Arey, Bruce W. & Schaef, Herbert T.
Partner: UNT Libraries Government Documents Department