Download or read book Modeling Three Dimensional Groundwater Flow and Advective Contaminant Transport at a Heterogeneous Mountainous Site in Support of Remediation Strategy written by and published by . This book was released on 2004 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: A calibrated groundwater flow model for a contaminated site can provide substantial information for assessing and improving hydraulic measures implemented for remediation. A three-dimensional transient groundwater flow model was developed for a contaminated mountainous site, at which interim corrective measures were initiated to limit further spreading of contaminants. This flow model accounts for complex geologic units that vary considerably in thickness, slope, and hydrogeologic properties, as well as large seasonal fluctuations of the groundwater table and flow rates. Other significant factors are local recharge from leaking underground storm drains and recharge from steep uphill areas. The zonation method was employed to account for the clustering of high and low hydraulic conductivities measured in a geologic unit. A composite model was used to represent the bulk effect of thin layers of relatively high hydraulic conductivity found within bedrock of otherwise low conductivity. The inverse simulator ITOUGH2 was used to calibrate the model for the distribution of rock properties. The model was initially calibrated using data collected between 1994 and 1996. To check the validity of the model, it was subsequently applied to predicting groundwater level fluctuation and groundwater flux between 1996 and 1998. Comparison of simulated and measured data demonstrated that the model is capable of predicting the complex flow reasonably well. Advective transport was approximated using pathways of particles originating from source areas of the plumes. The advective transport approximation was in good agreement with the trend of contaminant plumes observed over the years. The validated model was then refined to focus on a subsection of the large system. The refined model was subsequently used to assess the efficiency of hydraulic measures implemented for remediation.
Download or read book Modeling Groundwater Flow and Contaminant Transport written by Jacob Bear and published by Springer Science & Business Media. This book was released on 2010-01-18 with total page 851 pages. Available in PDF, EPUB and Kindle. Book excerpt: In many parts of the world, groundwater resources are under increasing threat from growing demands, wasteful use, and contamination. To face the challenge, good planning and management practices are needed. A key to the management of groundwater is the ability to model the movement of fluids and contaminants in the subsurface. The purpose of this book is to construct conceptual and mathematical models that can provide the information required for making decisions associated with the management of groundwater resources, and the remediation of contaminated aquifers. The basic approach of this book is to accurately describe the underlying physics of groundwater flow and solute transport in heterogeneous porous media, starting at the microscopic level, and to rigorously derive their mathematical representation at the macroscopic levels. The well-posed, macroscopic mathematical models are formulated for saturated, single phase flow, as well as for unsaturated and multiphase flow, and for the transport of single and multiple chemical species. Numerical models are presented and computer codes are reviewed, as tools for solving the models. The problem of seawater intrusion into coastal aquifers is examined and modeled. The issues of uncertainty in model input data and output are addressed. The book concludes with a chapter on the management of groundwater resources. Although one of the main objectives of this book is to construct mathematical models, the amount of mathematics required is kept minimal.
Download or read book Three dimensional Groundwater Flow and Contaminant Transport in Medium Scale Highly Heterogeneous Environments written by Ken A. Ewers and published by . This book was released on 1997 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development Report on the Idaho National Laboratory Sitewide Three Dimensional Aquifer Model written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A sub-regional scale, three-dimensional flow model of the Snake River Plain Aquifer was developed to support remediation decisions for Waste Area Group 10, Operable Unit 10 08 at the Idaho National Laboratory (INL) Site. This model has been calibrated primarily to water levels and secondarily to groundwater velocities interpreted from stable isotope disequilibrium studies and the movement of anthropogenic contaminants in the aquifer from facilities at the INL. The three-dimensional flow model described in this report is one step in the process of constructing a fully three-dimensional groundwater flow and contaminant transport model as prescribed in the Idaho National Engineering and Environmental Laboratory Operable Unit 10-08 Sitewide Groundwater Model Work Plan. An updated three-dimensional hydrogeologic conceptual model is presented along with the geologic basis for the conceptual model. Sediment-dominated three-dimensional volumes were used to represent the geology and constrain groundwater flow as part of the conceptual model. Hydrological, geochemical, and geological data were summarized and evaluated to infer aquifer behavior. A primary observation from development and evaluation of the conceptual model was that relative to flow on a regional scale, the aquifer can be treated with steady-state conditions. Boundary conditions developed for the three-dimensional flow model are presented along with inverse simulations that estimate parameterization of hydraulic conductivity. Inverse simulations were performed using the pilot-point method to estimate permeability distributions. Thermal modeling at the regional aquifer scale and at the sub-regional scale using the inverted permeabilities is presented to corroborate the results of the flow model. The results from the flow model show good agreement with simulated and observed water levels almost always within 1 meter. Simulated velocities show generally good agreement with some discrepancies in an interpreted low-velocity region near the toe of the Arco Hills. This discrepancy persisted in each of the aquifer bottom thickness scenarios that were simulated precluding decisions on which aquifer bottom thickness to use in transport simulations. When joint-calibration was performed using both water levels and velocities assigned as calibration targets, the discrepancy was prevented. This result highlighted the need to consider multiple calibration objectives and not rely solely on calibration to water levels. The next and last step in the process of constructing a fully three-dimensional groundwater flow and contaminant transport model will be calibration directly to transport from facilities. This last step will likely require further modification of the velocity fields resulting from the three-dimensional groundwater flow model presented in this report.
Download or read book Analytical Modeling of Solute Transport in Groundwater written by Mark Goltz and published by John Wiley & Sons. This book was released on 2017-02-08 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: Teaches, using simple analytical models how physical, chemical, and biological processes in the subsurface affect contaminant transport Uses simple analytical models to demonstrate the impact of subsurface processes on the fate and transport of groundwater contaminants Includes downloadable modeling tool that provides easily understood graphical output for over thirty models Modeling tool and book are integrated to facilitate reader understanding Collects analytical solutions from many sources into a single volume and, for the interested reader, shows how these solutions are derived from the governing model equations
Download or read book A Practical Guide to Groundwater and Solute Transport Modeling written by Karlheinz Spitz and published by Wiley-Interscience. This book was released on 1996-04-12 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: Focusing on modeling applications, this outstanding reference provides a step-by-step, non-mathematical approach to constructing and using realistic workable groundwater models on a daily basis. Extensive detailed drawings, case studies, practical examples, and sample models illustrate important concepts. Includes data on hydrogeologic features and pollutants plus a glossary of terms.
Download or read book Scientific Investigations Report written by Sharon E. Kroening and published by . This book was released on 2004 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Three dimensional Simulation of Groundwater Flow and Transport of Chemical and Low level Radioactive Constituents Within Two Production Areas of the Savannah River Plant written by and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Modeling of transport in the environmental media was performed. Predicting the future performance of any waste site or facility and postulated actions in terms of migration of potential hazardous materials requires mathematical models capable of simulating flow and transport in the groundwater. Three-dimensional groundwater flow and transport models were developed to simulate the groundwater movement and contaminant transport in the Raw Materials Fabrication Area and the Separations Area. The overall objective of the analysis was to develop groundwater flow models that quantifies the rate and direction of the groundwater movement from the waste sites to points of discharge. The USGS Modular 3D model uses the strongly implicit procedure to solve sets of simultaneous finite-difference equations that represent the groundwater flow process. The transport functions, which are the concentration or mass flux at time t due to continuous injection starting at time t', were obtained by solving the three-dimensional advection-dispersion equations using the Sandia Waste Isolation Flow and Transport (SWIFT) model. 5 refs., 7 figs., 2 tabs.
Download or read book A Three Dimensional Groundwater Flow and Contaminant Transport Model at the Hemet Sanitary Landfill written by and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mathematical Modeling of Groundwater Pollution written by Ne-Zheng Sun and published by Springer Science & Business Media. This book was released on 2014-07-08 with total page 391 pages. Available in PDF, EPUB and Kindle. Book excerpt: Groundwater is one of the most important resources in the world. In many areas, water supplies for industrial, domestic, and agricultural uses are de pendent on groundwater. As an "open" system, groundwater may exchange mass and energy with its neighboring systems (soil, air, and surface water) through adsorption, ion-exchange, infiltration, evaporation, inflow, outflow, and other exchange forms. Consequently, both the quantity and quality of groundwater may vary with environmental changes and human activities. Due to population growth, and industrial and agricultural development, more and more groundwater is extracted, especially in arid areas. If the groundwater management problem is not seriously considered, over extraction may lead to groundwater mining, salt water intrusion, and land subsidence. In fact, the quality of groundwater is gradually deteriorating throughout the world. The problem of groundwater pollution has appeared, not only in developed countries, but also in developing countries. Ground water pollution is a serious environmental problem that may damage human health, destroy the ecosystem, and cause water shortage.
Download or read book An Integrated Approach to Subsurface Heterogeneity Measurement for Three dimensional Ground Water Flow and Contaminant Transport Modeling written by Souad N. Al-Azzawi and published by . This book was released on 1990 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Three dimensional Method of characteristics Solute Transport Model MOC3D written by Leonard F. Konikow and published by . This book was released on 1996 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Modular Three dimensional Finite difference Ground water Flow Model written by Michael G. McDonald and published by . This book was released on 1984 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analysis of Groundwater Contaminant Transport with Three dimensional Scaled Models written by Ben L. Sill and published by . This book was released on 1991 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Hydrostrat Model and Alternatives for Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 99 written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The three-dimensional hydrostratigraphic framework model for the Rainier Mesa-Shoshone Mountain Corrective Action Unit was completed in Fiscal Year 2006. The model extends from eastern Pahute Mesa in the north to Mid Valley in the south and centers on the former nuclear testing areas at Rainier Mesa, Aqueduct Mesa, and Shoshone Mountain. The model area also includes an overlap with the existing Underground Test Area Corrective Action Unit models for Yucca Flat and Pahute Mesa. The model area is geologically diverse and includes un-extended yet highly deformed Paleozoic terrain and high volcanic mesas between the Yucca Flat extensional basin on the east and caldera complexes of the Southwestern Nevada Volcanic Field on the west. The area also includes a hydrologic divide between two groundwater sub-basins of the Death Valley regional flow system. A diverse set of geological and geophysical data collected over the past 50 years was used to develop a structural model and hydrostratigraphic system for the model area. Three deep characterization wells, a magnetotelluric survey, and reprocessed gravity data were acquired specifically for this modeling initiative. These data and associated interpretive products were integrated using EarthVision{reg_sign} software to develop the three-dimensional hydrostratigraphic framework model. Crucial steps in the model building process included establishing a fault model, developing a hydrostratigraphic scheme, compiling a drill-hole database, and constructing detailed geologic and hydrostratigraphic cross sections and subsurface maps. The more than 100 stratigraphic units in the model area were grouped into 43 hydrostratigraphic units based on each unit's propensity toward aquifer or aquitard characteristics. The authors organized the volcanic units in the model area into 35 hydrostratigraphic units that include 16 aquifers, 12 confining units, 2 composite units (a mixture of aquifer and confining units), and 5 intrusive confining units. The underlying pre-Tertiary rocks are divided into six hydrostratigraphic units, including three aquifers and three confining units. Other units include an alluvial aquifer and a Mesozoic-age granitic confining unit. The model depicts the thickness, extent, and geometric relationships of these hydrostratigraphic units ('layers' in the model). The model also incorporates 56 Tertiary normal faults and 4 Mesozoic thrust faults. The complexity of the model area and the non-uniqueness of some of the interpretations incorporated into the base model made it necessary to formulate alternative interpretations for some of the major features in the model. Four of these alternatives were developed so they can be modeled in the same fashion as the base model. This work was done for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office in support of the Underground Test Area Subproject of the Environmental Restoration Project.
Download or read book Large Scale Groundwater Flow and Contaminant Transport Modeling written by Karl Bandilla and published by . This book was released on 2009 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work introduces a combination of the vertically integrated Analytic Element and deterministic Streamline methods for watershed-scale groundwater flow and contaminant transport modeling. This new method combines the Analytic Element Method's ability of modeling large spatial domains while preserving stream-scale details, with the conceptional elegance of the Streamline method. Both methods allow for parallel processing in order to reduce model run-times. The intended use of this new method is the study of non-point source contaminant transport on the watershed scale (e.g., nutrient loading to surface water from agricultural fields). A new iterative Analytic Element Method algorithm is devised for solving 2D steady-state groundwater flow models containing large numbers of head-specified elements (e.g. rivers and lakes).^The new algorithm improves convergence of models containing head-specified elements by explicitly computing fluxes of all such features at the start of each iteration. The new algorithm alsoenables the use of efficient parallel processing on distributed-memory super-computers. The combination of parallel processing and reduced number of iterations significantly extends the size and complexity of problems that can be modeled using the Analytic Element Method. The vertically integrated Analytic Element Method flow solution is used to construct three-dimensional particle tracks that define the geometry of the Streamline Method by approximating vertical flow. The inherently parallel nature of the algorithm supports the development of reactive transport models for spatial domains much larger than current grid-based methods.^The applicability of the new approach is verified for cases with negligible transverse dispersion through comparisons to analytic solutions and existing numerical solutions, and parallel performance is demonstrated through a realistic test problem based on the regional-scale transport of agricultural contaminants from spatially distributed sources.
Download or read book Advective Control of Groundwater Contaminant Plumes Using Simulation and Optimization written by Ann Elizabeth Mulligan and published by . This book was released on 1999 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt:
