31 Matching Results

Search Results

Advanced search parameters have been applied.
in creator/contributor: "Rockhold, Mark L."  
Results: 1 - 24 next
open access

Uranium Contamination in the Subsurface Beneath the 300 Area, Hanford Site, Washington

Description: This report provides a description of uranium contamination in the subsurface at the Hanford Site's 300 Area. The principal focus is a persistence plume in groundwater, which has not attenuated as predicted by earlier remedial investigations. Included in the report are chapters on current conditions, hydrogeologic framework, groundwater flow modeling, and geochemical considerations. The report is intended to describe what is known or inferred about the uranium contamination for the purpose of m… more
Date: February 29, 2008
Creator: Peterson, Robert E.; Rockhold, Mark L.; Serne, R. Jeffrey; Thorne, Paul D. & Williams, Mark D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

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 … more
Date: July 30, 2007
Creator: Meyer, Philip D.; Ye, Ming; Rockhold, Mark L.; Neuman, Shlomo P. & Cantrell, Kirk J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Borehole Data Package for One CY 2005 CERCLA Well 699-S20-E10, 300-FF-5 Operable Unit, Hanford Site, Washington

Description: This report supplies the information obtained during drilling, characterization, and installation of the new groundwater monitoring well. This document also provides a compilation of hydrogeologic and well construction information obtained during drilling, well development, and sample collection/analysis activities.
Date: March 29, 2006
Creator: Williams, Bruce A.; Bjornstad, Bruce N.; Lanigan, David C.; Keller, Jason M. & Rockhold, Mark L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Compendium of Data for the Hanford Site (Fiscal Years 2004 to 2008) Applicable to Estimation of Recharge Rates

Description: This report is a compendium of recharge data collected in Fiscal Years 2004 through 2008 at various soil and surface covers found and planned in the 200 West and 200 East Areas of the U.S. Department of Energy’s Hanford Site in southeast Washington State. The addition of these new data to previously published recharge data will support improved estimates of recharge with respect to location and soil cover helpful to evaluations and risk assessments of radioactive and chemical wastes at this sit… more
Date: September 24, 2008
Creator: Nichols, William E.; Rockhold, Mark L. & Downs, Janelle L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Limited Field Investigation Report for Uranium Contamination in the 300 Area, 300-FF-5 Operable Unit, Hanford Site, Washington

Description: Four new CERCLA groundwater monitoring wells were installed in the 300-FF-5 Operable Unit in FY 2006 to fulfill commitments for well installations proposed in the Hanford Federal Facility Agreement and Consent Order Milestone M-24-57. Wells were installed to collect data to determine the distribution of process uranium and other contaminants of potential concern in groundwater. These data will also support uranium contaminant transport simulations and the wells will supplement the water quality… more
Date: November 1, 2007
Creator: Williams, Bruce A.; Brown, Christopher F.; Um, Wooyong; Nimmons, Michael J.; Peterson, Robert E.; Bjornstad, Bruce N. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Numerical Modeling of 90Sr and 137Cs Transport from a Spill in the B-Cell of the 324 Building, Hanford Site 300 Area

Description: To characterize the extent of contamination under the 324 Building, a pit was excavated on the north side of the building in 2010 by Washington Closure Hanford LLC (WCH). Horizontal closed-end steel access pipes were installed under the foundation of the building from this pit and were used for measuring temperatures and exposure rates under the B-Cell. The deployed sensors measured elevated temperatures of up to 61 C (142 F) and exposure rates of up to 8,900 R/hr. WCH suspended deactivation of… more
Date: March 19, 2012
Creator: Rockhold, Mark L.; Bacon, Diana H.; Freedman, Vicky L.; Lindberg, Michael J. & Clayton, Ray E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Multi-Scale Mass Transfer Processes Controlling Natural Attenuation and Engineered Remediation: An IFRC Focused on Hanford’s 300 Area Uranium Plume January 2010 to January 2011

Description: The Integrated Field Research Challenge (IFRC) at the Hanford Site 300 Area uranium (U) plume addresses multi-scale mass transfer processes in a complex subsurface hydrogeologic setting where groundwater and riverwater interact. A series of forefront science questions on reactive mass transfer focus research. These questions relate to the effect of spatial heterogeneities; the importance of scale; coupled interactions between biogeochemical, hydrologic, and mass transfer processes; and measurem… more
Date: February 1, 2011
Creator: Zachara, John M.; Bjornstad, Bruce N.; Christensen, John N.; Conrad, Mark S.; Fredrickson, Jim K.; Freshley, Mark D. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

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

Description: This report documents the requirements for transferring physical and hydraulic property data compiled by PNNL into the Hanford Environmental Information System (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 one of their current site contractors - CH2M-Hill Plateau Remediation Company (CHPRC). The objective of Task 1, Activ… more
Date: March 31, 2009
Creator: Rockhold, Mark L. & Middleton, Lisa A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Status Report for Remediation Decision Support Project, Task 1, Activity 1.B – Physical and Hydraulic Properties Database and Interpretation

Description: The objective of Activity 1.B of the Remediation Decision Support (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. In past years efforts were made by RDS project staff to compile all available physical and hydraulic property data for Hanfor… more
Date: September 26, 2008
Creator: Rockhold, Mark L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

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 … more
Date: July 24, 2009
Creator: Last, George V.; Rockhold, Mark L.; Murray, Christopher J. & Cantrell, Kirk J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

300 Area Uranium Stabilization Through Polyphosphate Injection: Final Report

Description: The objective of the treatability test was to evaluate the efficacy of using polyphosphate injections to treat uranium-contaminated groundwater in situ. A test site consisting of an injection well and 15 monitoring wells was installed in the 300 Area near the process trenches that had previously received uranium-bearing effluents. This report summarizes the work on the polyphosphate injection project, including bench-scale laboratory studies, a field injection test, and the subsequent analysis … more
Date: June 30, 2009
Creator: Vermeul, Vincent R.; Bjornstad, Bruce N.; Fritz, Brad G.; Fruchter, Jonathan S.; Mackley, Rob D.; Newcomer, Darrell R. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Three-Dimensional Groundwater Models of the 300 Area at the Hanford Site, Washington State

Description: Researchers at Pacific Northwest National Laboratory developed field-scale groundwater flow and transport simulations of the 300 Area to support the 300-FF-5 Operable Unit Phase III Feasibility Study. The 300 Area is located in the southeast portion of the U.S. Department of Energy’s Hanford Site in Washington State. Historical operations involving uranium fuel fabrication and research activities at the 300 Area have contaminated engineered liquid-waste disposal facilities, the underlying vados… more
Date: September 1, 2008
Creator: Williams, Mark D.; Rockhold, Mark L.; Thorne, Paul D. & Chen, Yousu
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Interim Report: 100-NR-2 Apatite Treatability Test: Low Concentration Calcium Citrate-Phosphate Solution Injection for In Situ Strontium-90 Immobilization

Description: Following an evaluation of potential Sr-90 treatment technologies and their applicability under 100-NR-2 hydrogeologic conditions, U.S. Department of Energy, Fluor Hanford, Inc., Pacific Northwest National Laboratory, and the Washington Department of Ecology agreed that the long-term strategy for groundwater remediation at 100-N Area will include apatite sequestration as the primary treatment, followed by a secondary treatment if necessary (most likely phytoremediation). Since then, the agencie… more
Date: July 11, 2008
Creator: Williams, Mark D.; Fritz, Brad G.; Mendoza, Donaldo P.; Rockhold, Mark L.; Thorne, Paul D.; Xie, YuLong et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Integrated Field, Laboratory, and Modeling Studies to Determine the Effects of Linked Microbial and Physical Spatial Heterogeneity on Engineered Vadose Zone Bioremediation

Description: Executive Summary - While numerous techniques exist for remediation of contaminant plumes in groundwater or near the soil surface, remediation methods in the deep vadose zone are less established due to complex transport dynamics and sparse microbial populations. There is a lack of knowledge on how physical and hydrologic features of the vadose zone control microbial growth and colonization in response to nutrient delivery during bioremediation. Yet pollution in the vadose zone poses a serious … more
Date: October 31, 2004
Creator: Brockman, Fred J.; Selker, John S. & Rockhold, Mark L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Multi-Scale Mass Transfer Processes Controlling Natural Attenuation and Engineered Remediation: An IFRC Focused on Hanford’s 300 Area Uranium Plume January 2011 to January 2012

Description: The Integrated Field Research Challenge (IFRC) at the Hanford Site 300 Area uranium (U) plume addresses multi-scale mass transfer processes in a complex subsurface biogeochemical setting where groundwater and riverwater interact. A series of forefront science questions on reactive mass transfer motivates research. These questions relate to the effect of spatial heterogeneities; the importance of scale; coupled interactions between biogeochemical, hydrologic, and mass transfer processes; and mea… more
Date: March 5, 2012
Creator: Zachara, John M.; Bjornstad, Bruce N.; Christensen, John N.; Conrad, Mark S.; Fredrickson, Jim K.; Freshley, Mark D. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Prototype Data Models and Data Dictionaries for Hanford Sediment Physical and Hydraulic Properties

Description: The Remediation Decision Support (RDS) project, managed by the Pacific Northwest National Laboratory (PNNL) for the U.S. Department of Energy (DOE) and the CH2M HILL Plateau Remediation Company (CHPRC), has been compiling physical and hydraulic property data and parameters to support risk analyses and waste management decisions at Hanford. In FY09 the RDS project developed a strategic plan for a physical and hydraulic property database. This report documents prototype data models and dictionari… more
Date: September 30, 2010
Creator: Rockhold, Mark L.; Last, George V. & Middleton, Lisa A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Carbon Tetrachloride Flow and Transport in the Subsurface of the 216-Z-18 Crib and 216-Z-1A Tile Field at the Hanford Site: Multifluid Flow Simulations and Conceptual Model Update

Description: Carbon tetrachloride (CT) was discharged to the 216-Z-9, Z-1A, and Z-18 waste sites that are included in the 200-PW-1 Operable Unit in Hanford 200 West Area. Fluor Hanford, Inc. is conducting a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) remedial investigation/feasibility study (RI/FS) for the 200-PW-1 Operable Unit. As part of this overall effort, Pacific Northwest National Laboratory (PNNL) was contracted to improve the conceptual model of how CT is distribu… more
Date: October 31, 2006
Creator: Oostrom, Mart; Rockhold, Mark L.; Thorne, Paul D.; Last, George V. & Truex, Michael J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Treatability Test Plan for 300 Area Uranium Stabilization through Polyphosphate Injection

Description: The U.S. Department of Energy has initiated a study into possible options for stabilizing uranium at the 300 Area using polyphosphate injection. As part of this effort, PNNL will perform bench- and field-scale treatability testing designed to evaluate the efficacy of using polyphosphate injections to reduced uranium concentrations in the groundwater to meet drinking water standards (30 ug/L) in situ. This technology works by forming phosphate minerals (autunite and apatite) in the aquifer that … more
Date: June 1, 2007
Creator: Vermeul, Vincent R.; Williams, Mark D.; Fritz, Brad G.; Mackley, Rob D.; Mendoza, Donaldo P.; Newcomer, Darrell R. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Data Assimilation Tools for CO2 Reservoir Model Development – A Review of Key Data Types, Analyses, and Selected Software

Description: Pacific Northwest National Laboratory (PNNL) has embarked on an initiative to develop world-class capabilities for performing experimental and computational analyses associated with geologic sequestration of carbon dioxide. The ultimate goal of this initiative is to provide science-based solutions for helping to mitigate the adverse effects of greenhouse gas emissions. This Laboratory-Directed Research and Development (LDRD) initiative currently has two primary focus areas—advanced experimental… more
Date: September 30, 2009
Creator: Rockhold, Mark L.; Sullivan, E. C.; Murray, Christopher J.; Last, George V. & Black, Gary D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Sequestration of Sr-90 Subsurface Contamination in the Hanford 100-N Area by Surface Infiltration of a Ca-Citrate-Phosphate Solution

Description: The objective of this project is to develop a method to emplace apatite precipitate in the 100N vadose zone, which results in sorption and ultimately incorporation of Sr-90 into the apatite structure. The Ca-citrate-PO4 solution can be infiltrated into unsaturated sediments to result in apatite precipitate to provide effective treatment of Sr-90 contamination. Microbial redistribution during solution infiltration and a high rate of citrate biodegradation for river water microbes (water used for… more
Date: March 1, 2009
Creator: Szecsody, James E.; Rockhold, Mark L.; Oostrom, Martinus; Moore, R. C.; Burns, Carolyn A.; Williams, Mark D. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A Long-Term Strategic Plan for Hanford Sediment Physical Property and Vadose Zone Hydraulic Parameter Databases

Description: Physical property data and unsaturated hydraulic parameters are critical input for analytic and numerical models used to predict transport and fate of contaminants in variably saturated porous media and to assess and execute remediation alternatives. The Remediation Decision Support (RDS) project, managed by the Pacific Northwest National Laboratory (PNNL) for the U.S. Department of Energy (DOE) and the CH2M Hill Plateau Remediation Company (CHPRC), has been compiling physical and hydraulic pro… more
Date: September 30, 2009
Creator: Rockhold, Mark L.; Last, George V. & Middleton, Lisa A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Hanford 100-N Area In Situ Apatite and Phosphate Emplacement by Groundwater and Jet Injection: Geochemical and Physical Core Analysis

Description: The purpose of this study is to evaluate emplacement of phosphate into subsurface sediments in the Hanford Site 100-N Area by two different technologies: groundwater injection of a Ca-citrate-PO4 solution and water-jet injection of sodium phosphate and/or fish-bone apatite. In situ emplacement of phosphate and apatite adsorbs, then incorporates Sr-90 into the apatite structure by substitution for calcium. Overall, both technologies (groundwater injection of Ca-citrate-PO4) and water-jet injecti… more
Date: July 1, 2010
Creator: Szecsody, James E.; Vermeul, Vincent R.; Fruchter, Jonathan S.; Williams, Mark D.; Rockhold, Mark L.; Qafoku, Nikolla et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Soil Water Balance and Recharge Monitoring at the Hanford Site - FY09 Status Report

Description: Recharge provides the primary driving force for transporting contaminants from the vadose zone to underlying aquifer systems. Quantification of recharge rates is important for assessing contaminant transport and fate and for evaluating remediation alternatives. This report describes the status of soil water balance and recharge monitoring performed by Pacific Northwest National Laboratory at the Hanford Site for Fiscal Year 2009. Previously reported data for Fiscal Years 2004 - 2008 are updated… more
Date: September 28, 2009
Creator: Rockhold, Mark L.; Saunders, Danielle L.; Strickland, Christopher E.; Waichler, Scott R. & Clayton, Ray E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Quantifying Vadose Zone Flow and Transport Uncertainties Using a Unified, Hierarchical Approach

Description: The objective of this research is to develop and demonstrate a general approach for modeling flow and transport in the heterogeneous vadose zone. The approach uses similar media scaling, geostatistics, and conditional simulation methods to estimate soil hydraulic parameters at unsampled locations from field-measured water content data and scale-mean hydraulic parameters determined from available site characterization data. Neural network methods are being developed to estimate soil hydraulic pa… more
Date: June 1, 2002
Creator: Meyer, Philip D.; Murray, Christopher J.; Rockhold, Mark L. & Schaap, Marcel
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
Back to Top of Screen