Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 30 of 62

Full-Text Articles in Engineering

Active Layer Groundwater Flow: The Interrelated Effects Of Stratigraphy, Thaw, And Topography, Michael T. O'Connor, M. Bayani Cardenas, Bethany T. Neilson, Kindra D. Nicholaides, George W. Kling Jul 2019

Active Layer Groundwater Flow: The Interrelated Effects Of Stratigraphy, Thaw, And Topography, Michael T. O'Connor, M. Bayani Cardenas, Bethany T. Neilson, Kindra D. Nicholaides, George W. Kling

Civil and Environmental Engineering Faculty Publications

The external drivers and internal controls of groundwater flow in the thawed “active layer” above permafrost are poorly constrained because they are dynamic and spatially variable. Understanding these controls is critical because groundwater can supply solutes such as dissolved organic matter to surface water bodies. We calculated steady‐state three‐dimensional suprapermafrost groundwater flow through the active layer using measurements of aquifer geometry, saturated thickness, and hydraulic properties collected from two major landscape types over time within a first‐order Arctic watershed. The depth position and thickness of the saturated zone is the dominant control of groundwater flow variability between sites and during …


Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith Nov 2018

Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith

Civil and Environmental Engineering Faculty Publications

The goals of the original proposed project remain the same, that is, to test the hypothesis that Managed Aquifer Recharge (MAR) for stormwater harvesting is a technically feasible, socially and environmentally acceptable, economically viable, and legally feasible option for developing new water supplies for arid Western urban ecosystems experiencing increasing population, and climate change pressures on existing water resources. The project is being carried out via three distinct but integrated components that include: 1) Monitoring of existing distributed MAR harvesting schemes involving a growing number of demonstration Green Infrastructure (GI) test sites; 2) Integrated stormwater/vadose zone/groundwater/ ecosystem services modeling; and …


Groundwater Flow And Exchange Across The Land Surface Explain Carbon Export Patterns In Continuous Permafrost Watersheds, Bethany T. Neilson, M. Bayani Cardenas, Michael T. O'Connor, Mitchell T. Rasmussen, Tyler V. King, George W. Kling Aug 2018

Groundwater Flow And Exchange Across The Land Surface Explain Carbon Export Patterns In Continuous Permafrost Watersheds, Bethany T. Neilson, M. Bayani Cardenas, Michael T. O'Connor, Mitchell T. Rasmussen, Tyler V. King, George W. Kling

Civil and Environmental Engineering Faculty Publications

Groundwater flow regimes in the seasonally thawed soils in areas of continuous permafrost are relatively unknown despite their potential role in delivering water, carbon, and nutrients to streams. Using numerical groundwater flow models informed by observations from a headwater catchment in arctic Alaska, United States, we identify several mechanisms that result in substantial surface‐subsurface water exchanges across the land surface during downslope transport and create a primary control on dissolved organic carbon loading to streams and rivers. The models indicate that surface water flowing downslope has a substantial groundwater component due to rapid surface‐subsurface exchanges across a range of hydrologic …


Stream Centric Methods For Determining Groundwater Contributions In Karst Mountain Watersheds, Bethany T. Neilson, Hyrum Tennant, Trinity L. Stout, Matthew P. Miller, Rachel S. Gabor, Yusuf Jameel, Mallory Millington, Andrew Gelderloos, Gabriel J. Bowen, Paul D. Brooks Aug 2018

Stream Centric Methods For Determining Groundwater Contributions In Karst Mountain Watersheds, Bethany T. Neilson, Hyrum Tennant, Trinity L. Stout, Matthew P. Miller, Rachel S. Gabor, Yusuf Jameel, Mallory Millington, Andrew Gelderloos, Gabriel J. Bowen, Paul D. Brooks

Civil and Environmental Engineering Faculty Publications

Climate change influences on mountain hydrology are uncertain but likely to be mediated by variability in subsurface hydrologic residence times and flow paths. The heterogeneity of karst aquifers adds complexity in assessing the resiliency of these water sources to perturbation, suggesting a clear need to quantify contributions from and losses to these aquifers. Here we develop a stream centric method that combines mass and flow balances to quantify net and gross gains and losses at different spatial scales. We then extend these methods to differentiate between karst conduit and matrix contributions from the aquifer. In the Logan River watershed in …


Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith Nov 2017

Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith

Civil and Environmental Engineering Faculty Publications

The aims of the original proposed project remain the same, that is, to test the hypothesis that Managed Aquifer Recharge (MAR) for stormwater harvesting is a technically feasible, socially and environmentally acceptable, economically viable, and legally feasible option for developing new water supplies for arid Western urban ecosystems experiencing increasing population, and climate change pressures on existing water resources. The project is being carried out via three distinct but integrated components that include: 1) Monitoring of existing distributed MAR harvesting schemes involving a growing number of demonstration Green Infrastructure (GI) test sites; 2) Integrated stormwater/vadose zone/groundwater/ ecosystem services modeling; and …


Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith Nov 2016

Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith

Civil and Environmental Engineering Faculty Publications

The aims of the original proposed project remain the same, that is, to test the hypothesis that Managed Aquifer Recharge (MAR) for stormwater harvesting is a technically feasible, socially and environmentally acceptable, economically viable, and permittable option for developing new water supplies for arid Western urban ecosystems experiencing increasing population, and climate change pressures on existing water resources. The project is being carried out via three distinct but integrated components that include: 1) Monitoring of existing distributed Managed Aquifer Recharge (MAR) harvesting schemes involving a growing number of demonstration Green Infrastructure (GI) test sites; 2) Integrated stormwater/vadose zone/groundwater/ ecosystem services …


Digitalcrust - A 4d Data System Of Material Properties For Transforming Research On Crustal Fluid Flow, Y. Fan, S. Richard, R. S. Bristol, S. E. Peters, S. E. Ingebritsen, N. Moosdorf, A. Packman, T. Gleeson, I. Zaslavsky, S. Peckham, L. Murdoch, M. Fienen, David G. Tarboton, N. Jones, Richard P. Hooper, J. Arrigo, D. Gochis, J. R. Olson, D. Wolock Oct 2014

Digitalcrust - A 4d Data System Of Material Properties For Transforming Research On Crustal Fluid Flow, Y. Fan, S. Richard, R. S. Bristol, S. E. Peters, S. E. Ingebritsen, N. Moosdorf, A. Packman, T. Gleeson, I. Zaslavsky, S. Peckham, L. Murdoch, M. Fienen, David G. Tarboton, N. Jones, Richard P. Hooper, J. Arrigo, D. Gochis, J. R. Olson, D. Wolock

Civil and Environmental Engineering Faculty Publications

Fluid circulation in the Earth's crust plays an essential role in surface, near surface, and deep crustal processes. Flow pathways are driven by hydraulic gradients but controlled by material permeability, which varies over many orders of magnitude and changes over time. Although millions of measurements of crustal properties have been made, including geophysical imaging and borehole tests, this vast amount of data and information has not been integrated into a comprehensive knowledge system. A community data infrastructure is needed to improve data access, enable large‐scale synthetic analyses, and support representations of the subsurface in Earth system models. Here, we describe …


Impact Of Vegetable Oil On Distribution Of Trichloroethylene In Groundwater During Enhanced Bioremediation, M. Pu, Ryan Dupont, William J. Doucette Oct 2008

Impact Of Vegetable Oil On Distribution Of Trichloroethylene In Groundwater During Enhanced Bioremediation, M. Pu, Ryan Dupont, William J. Doucette

Civil and Environmental Engineering Faculty Publications

Vegetable oils are increasingly being used as long-term carbon donors to stimulate reductive dechlorination of trichloroethylene (TCE). Besides potential enhancement of biodegradation, the addition of vegetables oils may impact TCE fate and distribution within the aquifer by acting as non-aqueous phase liquids (NAPL). Distribution coefficients for TCE between groundwater and four vegetable oils were determined using a slow-stir technique. Log vegetable oil/water distribution coefficients (log Kvw) were found to range from 1.0 to 2.56. TCE/vegetable oil distribution coefficients statistically increased with an increase in oil weathering while the concentration of dissolved organic carbon (DOC) in the water did not change …


Integrated Modeling Of Nitrate Contamination Of Groundwater In Agriculture-Dominated Watersheds, M. Almasri, Jagath J. Kaluarachchi Sep 2007

Integrated Modeling Of Nitrate Contamination Of Groundwater In Agriculture-Dominated Watersheds, M. Almasri, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

This paper presents and implements a framework for modeling the impact of land use practices and protection alternatives on nitrate pollution of groundwater in agricultural watersheds. The framework utilizes the national land cover database (NLCD) of the United State Geological Survey (USGS) grid and a geographic information system (GIS) to account for the spatial distribution of on-ground nitrogen sources and corresponding loadings. The framework employs a soil nitrogen dynamic model to estimate nitrate leaching to groundwater. These estimates were used in developing a groundwater nitrate fate and transport model. The framework considers both point and non-point sources of nitrogen across …


Optimization Modeling For Groundwater And Conjunctive Use Water Policy Development, Richard C. Peralta, R. Shulstad Jan 2004

Optimization Modeling For Groundwater And Conjunctive Use Water Policy Development, Richard C. Peralta, R. Shulstad

Civil and Environmental Engineering Faculty Publications

Planners must sometimes decide how to restrict or reduce groundwater use to prevent unacceptable future problems. Often there are several alternatives (policies). Comparing policies can involve formulating a sustained groundwater yield optimization problem and computing an optimal groundwater pumping strategy for each. This is easy via the SOMOS simulation/optimization (S/O) model. Subsequent analysis can include: flow simulation to predict transient water level response to pumping; and economic evaluation to estimate costs and returns. Two examples predict the best consequences of potential physical and legal management policies for alluvial and valley basin fill aquifers hydraulically linked to surface waters. Results show …


Practical Simulation /Optimization Modeling For Groundwater Quality And Quantity Management, Richard C. Peralta, Ineke M. Kalwij, Shengjun Wu Jan 2003

Practical Simulation /Optimization Modeling For Groundwater Quality And Quantity Management, Richard C. Peralta, Ineke M. Kalwij, Shengjun Wu

Civil and Environmental Engineering Faculty Publications

Software for mathematically optimizing groundwater management has improved significantly in recent years. The SOMOS code can readily handle large complex plume and water management problems. Most recently, it developed a least-cost $40.82M 30-yr pumping strategy for the 6.58 mile long Blaine NAD plume. That strategy was 19 percent better than the strategy developed simultaneously by an experienced consultant using normal trial and error simulation procedures. The management problem involved 60 stress periods, and well installation and pumping rates that could change every 10 periods. The optimal strategy employed 10 new wells. At a simpler site, SOMOS helped select robust strategies …


Simulation/Optimization Applications And Software For Optimal Ground-Water And Conjunctive Water Management, Richard C. Peralta Jan 2001

Simulation/Optimization Applications And Software For Optimal Ground-Water And Conjunctive Water Management, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Diverse water management simulation/optimization (S/O) experiences promoted the development of many S/O modeling approaches and models. Several of these are being incorporated within the Simulation/Optimization Modeling System (SOMOS). Non-modeler water scientists or engineers can apply one SOMOS module to optimize field-scale groundwater and conjunctive water management. Experienced groundwater modelers can apply other modules to optimally manage complex heterogeneous aquifer and stream-aquifer systems. SOMOS employs a variety of simulation models and approaches and optimization algorithms to optimize flow and contaminant management. SOMOS or its precursor modules have been well proven in real-world projects. Designed for use by consultants, students, academics, and …


Computing Optimal Pumping Strategies For Groundwater Contaminant Plume Remediation, Richard C. Peralta, Alaa H. Aly Sep 2000

Computing Optimal Pumping Strategies For Groundwater Contaminant Plume Remediation, Richard C. Peralta, Alaa H. Aly

Civil and Environmental Engineering Faculty Publications

Simulation/Optimization (S/0) models can greatly simplify the process of designing remediation systems for contaminated groundwater. We describe some technical aspects of using S/0 models and possible S/0 model formulations for groundwater remediation design. We: discuss some S/0 model optimization algorithms; illustrate simple optimization problem solution; describe two real-world S/0 model applications; and demonstrate S/0 model application under uncertainty.


Comparison Of A Genetic Algorithm And Mathematical Programming To The Design Of Groundwater Cleanup Systems, Alaa H. Aly, Richard C. Peralta Aug 1999

Comparison Of A Genetic Algorithm And Mathematical Programming To The Design Of Groundwater Cleanup Systems, Alaa H. Aly, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

We present and apply a new simulation/optimization approach for single- and multiple-planning period problems in groundwater remediation. Instead of the traditional control locations for contaminant concentrations, we use an LQC norm as a global measure of aquifer contamination (CMAX). We use response-surface constraints to represent CMAX within the optimization model. We compare the performance of formal mixed integer nonlinear programming and a genetic algorithm for several optimization scenarios.


Conjunctive Use Of Surface Water And Groundwater For Sustainable Agricultural Production, Richard C. Peralta Jan 1999

Conjunctive Use Of Surface Water And Groundwater For Sustainable Agricultural Production, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

This report is a guide to aid conjunctive water use in stream-aquifer systems. Conjunctive use refers to coordinated use of groundwater and surface water resources. This document discusses principles useful for field engineers and agricultural experts. It presents hydrologic and hydraulic principles and quantitative and qualitative parameters relating to sustainable conjunctive use. It provides tools and software.


Optimizing Separate Phase Light Hydrocarbon Recovery From Contaminated Unconfined Aquifers, G. S. Cooper, Richard C. Peralta, Jagath J. Kaluarachchi Apr 1998

Optimizing Separate Phase Light Hydrocarbon Recovery From Contaminated Unconfined Aquifers, G. S. Cooper, Richard C. Peralta, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

A modeling approach is presented that optimizes separate phase recovery of light non-aqueous phase liquids (LNAPL) for a single dual-extraction well in a homogeneous, isotropic unconfined aquifer. A simulation/regression/optimization (S/R/O) model is developed to predict, analyze, and optimize the oil recovery process. The approach combines detailed simulation, nonlinear regression, and optimization. The S/R/O model utilizes nonlinear regression equations describing system response to time-varying water pumping and oil skimming. Regression equations are developed for residual oil volume and free oil volume. The S/R/O model determines optimized time-varying (stepwise) pumping rates which minimize residual oil volume and maximize free oil recovery while …


Remax: Software For Optimizing Ground-Water Management, Conjunctive Water Management, And Remediation Design, Richard C. Peralta, Alaa H. Aly Jan 1998

Remax: Software For Optimizing Ground-Water Management, Conjunctive Water Management, And Remediation Design, Richard C. Peralta, Alaa H. Aly

Civil and Environmental Engineering Faculty Publications

REMAX is a software package designed to assist water managers in developing optimal ground water or coordinated ground water/surface water strategies for a wide range of management problems. REMAX uses MODFLOW, MT3D, and other simulation models to develop the response matrix or response surface equations employed in the final optimization model. To address nonlinear systems (e.g., unconfined aquifers) accurately, REMAX uses a modified response-matrix method. REMAX several nonlinear functions to represent a wide variety of nonlinear response surfaces. REMAX can be used for deterministic or reliability-based optimization problems. Decision variables are ground-water extraction/injection rates and/or surface water diversion rates. State …


Optimizing Conjunctive Use And Groundwater Yield, Richard C. Peralta, Rahman Rahimzadegen, Narendra K. Tyagi May 1997

Optimizing Conjunctive Use And Groundwater Yield, Richard C. Peralta, Rahman Rahimzadegen, Narendra K. Tyagi

Civil and Environmental Engineering Faculty Publications

Advances in computer power and mathematical optimization procedures can improve planning and developing sustainable irrigation systems. Simulation and optimization models can help plm1 groundwater and conjunctive use strategies to best achieve management goals while satisfying mm1agement a11d physical constraints. Simulation/optimization models that couple calibrated flow and transport simulation models with optimization algorithms can help design the best water management strategies. Mm1agers can be relatively sure that the groundwater system will respond acceptably when appropriate procedures are employed to develop the water management strategies. Presented case studies illustrate situations in which developed strategies simultaneously address conflicting management goals such as: maximizing …


Introduction To Simulation/Optimization Modeling For Groundwater Containment Remediation And (B) Ramifications Of Applying S/O Modeling To Groundwater Containment Remediation, With Case Study Examples, Richard C. Peralta Jan 1997

Introduction To Simulation/Optimization Modeling For Groundwater Containment Remediation And (B) Ramifications Of Applying S/O Modeling To Groundwater Containment Remediation, With Case Study Examples, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Normal use of a simulation model to develop a groundwater extraction/injection strategy employs the following process: (1) specify management goals, (2) assume a pumping strategy, (3) simulate system response to the pumping strategy, (4) evaluate acceptability of the system responses, (5) repeat steps (2-4) as required. This is a trial and error approach that is unlikely to actually yield the best pumping strategy for complicated problems


Software For Optimizing Groundwater Or Conjunctive Water Management, Richard C. Peralta, Alaa H. Aly Jun 1996

Software For Optimizing Groundwater Or Conjunctive Water Management, Richard C. Peralta, Alaa H. Aly

Civil and Environmental Engineering Faculty Publications

US/REMAX is a computer program designed to assist water managers in developing optimal groundwater and/or surface water strategies for a wide range of management problems. It employs response matrix, regression and other methods adapted for nonlinear systems. US/REMAX performs deterministic or reliability-based, single- or multi-objective optimization. Decision variables are ground-water extraction/injection and/or surface water diversion. State variables include water flows, stages and concentrations. Hard coded objective functions and constraints are linear, nonlinear, integer or mixed integer. Special constraints can be added to address unusual situations.


Toward A Balanced Strategy To Address Contaminated Groundwater Plumes At The Massachusetts Military Reservation, Richard C. Peralta May 1996

Toward A Balanced Strategy To Address Contaminated Groundwater Plumes At The Massachusetts Military Reservation, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

This document contains the findings and recommendations of the Technical Review and Evaluation Team (TRET) for the plume containment project at the Massachusetts Military Reservation (MMR). The findings and recommendations are in response to the 60 Percent Plume Containment Design, submitted by Operational Technologies (OpTech) in January 1996. In short, the TRET recommends the MMR depart substantially from the strategy of simultaneous, 100 percent containment and treatment that was assigned to OpTech for design in accordance with the Record of Decision (ROD) for Interim Action. This strategy guided the course of the plume containment project over the past two years


Considering Ecological Constraints While Optimizing Sustained Groundwater Yield, Pahvant Valley, Utah, Getachew Belaineh, Richard C. Peralta Apr 1995

Considering Ecological Constraints While Optimizing Sustained Groundwater Yield, Pahvant Valley, Utah, Getachew Belaineh, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Concern for groundwater quality and availability is increasing in Pahvant Valley. Ground-water levels are declining due to intense groundwater extraction for irrigation; water having high total dissolved solids concentration is flowing from the southwest toward the pumping sites; and discharge from natural springs in a wildlife refuge is declining. Transient simulation of aquifer response to 20 years of the 1985 pumping rates (beginning with 1985 groundwater level) predicted that spring discharge would decrease by as much as 87% from 1985 rates. Presented are preliminary pumping strategies that maximize sustainable, steady-state groundwater extraction without unacceptably reducing discharge from the springs. A …


Assuring A Long Term Groundwater Supply: Issues, Goals And Tools, Richard C. Peralta Mar 1995

Assuring A Long Term Groundwater Supply: Issues, Goals And Tools, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Groundwater is a hidden, but important resource. We can practicably define groundwater as water beneath the ground surface that can be extracted by wells. Other water in the ground that is not considered to be available for man’s direct use is commonly called “subsurface water.” Subsurface water includes moisture within the root zone.


Optimal Perennial Groundwater Yield Planning For Complex Nonlinear Aquifers: Methods And Examples, Shu Takahashi, Richard C. Peralta Jan 1995

Optimal Perennial Groundwater Yield Planning For Complex Nonlinear Aquifers: Methods And Examples, Shu Takahashi, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Optimal perennial groundwater yield pumping strategies were computed for a complex multilayer aquifer with: (i) confined and unconfined flow, and (ii) many flows typically described by piecewise-linear (nonsmooth) equations. The latter flows account for over 50% of the aquifer discharge from the test area, the eastern shore of the Great Salt Lake in Utah. Normally utilized response matrix (RM) and embedding (EM) simulation/optimization modelling procedures did not converge to optimal solutions for this area; they diverged or oscillated. However, the newly presented linear RM and EM approaches satisfactorily addressed the nonlinearities posed by over 2000 piecewise-linear constraints for evapotranspiration, discharge …


Pc Software For Optimizing Groundwater Contaminant Plume Capture And Containment, Richard C. Peralta, Herminio H. Suguino, Alaa H. Aly Feb 1994

Pc Software For Optimizing Groundwater Contaminant Plume Capture And Containment, Richard C. Peralta, Herminio H. Suguino, Alaa H. Aly

Civil and Environmental Engineering Faculty Publications

Simulation/optimization (S/0) models can be used to speed the process of computing desirable groundwater pumping strategies for plume management. They make the process of computing optimal strategies fairly straightforward and can help minimize the labor and cost of groundwater contaminant cleanup.


Preventing Pesticide Contamination Of Groundwater While Maximizing Irrigated Crop Yield, Richard C. Peralta, M. A. Hegazy, G. Musharrafieh Jan 1994

Preventing Pesticide Contamination Of Groundwater While Maximizing Irrigated Crop Yield, Richard C. Peralta, M. A. Hegazy, G. Musharrafieh

Civil and Environmental Engineering Faculty Publications

A simulation/optimization model is developed for maximizing irrigated crop yield while avoiding unacceptable pesticide leaching. The optimization model is designed to help managers prevent non-point source contamination of shallow groundwater aquifers. It computes optimal irrigation amounts for given soil, crop, chemical, and weather data and irrigation frequencies. It directly computes the minimum irrigated crop yield reduction needed to prevent groundwater contamination. Constraint equations used in the model maintain a layered soil moisture volume balance; describe percolation, downward unsaturated zone solute transport and pesticide degradation; and limit the amount of pesticide reaching groundwater. Constraints are linear, piecewise linear, nonlinear, and exponential. …


Ground-Water Policy-Making Support: Usem Optimization Modelling Plus Gis And Graphics, Richard C. Peralta, Christopher M. U. Neale, Ali Gharbi, Mazibur Khan, Oscar Daza, Douglas Ramsey, Kurt Vest Aug 1992

Ground-Water Policy-Making Support: Usem Optimization Modelling Plus Gis And Graphics, Richard C. Peralta, Christopher M. U. Neale, Ali Gharbi, Mazibur Khan, Oscar Daza, Douglas Ramsey, Kurt Vest

Civil and Environmental Engineering Faculty Publications

A support tool for ground-water management decision making involves integration of a multiobjective optimization model, GIS and graphics software. Two results are improved consideration of spatial data within the optimization model and improved conversion of optimal strategies to real-world application. Another result is improved visualization of the trade-offs involved between conflicting management goals.


Optimizing Perennial Groundwater Yield Planning For Nonlinear Systems: Approach Comparison, Shu Takahashi, Richard C. Peralta Jan 1992

Optimizing Perennial Groundwater Yield Planning For Nonlinear Systems: Approach Comparison, Shu Takahashi, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Four alternative simulation/optimization models useful for computing optimal sustained-yield (steady-state) groundwater pumping strategies are compared in terms of formulation, solution procedure, accuracy, and computational efficiency. The different models require different computer processing time and memory. For the aquifer tested system, if more than 10% of the cells have pumping as a decision variable, a fully linearized embedding model will require less computer memory than any other model. All the models address linear and nonlinear steady-state flow in multilayer, unconfined/confined aquifers. They also address several types of nonsmooth external flows. Newly presented are a response matrix model solving external flows described …


Optimizing Ground Water Planning And Management, Richard C. Peralta, L. S. Willardson Jan 1992

Optimizing Ground Water Planning And Management, Richard C. Peralta, L. S. Willardson

Civil and Environmental Engineering Faculty Publications

Simulation/optimization (S/0) models can be used to speed the process of computing long term groundwater pumping strategies. These combined models can also greatly ease the planning tasks of water management agencies. They make the process of computing optimal perennial yield groundwater management strategies fairly straightforward. S/0 models dramatically improve conjunctive water management and can help minimize the cost of groundwater contaminant clean-up. The differences between S/0 models and the simulation (S) models currently used by over 98 % of practitioners are illustrated with recent applications of S/0 models in regional planning.


Optimal Perennial Groundwater Yield Planning For The East Shore Area, Utah, Shu Takahashi, Richard C. Peralta Jan 1992

Optimal Perennial Groundwater Yield Planning For The East Shore Area, Utah, Shu Takahashi, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Computer models are developed for computing optimal perennial groundwater withdrawal strategies for the East Shore Area of Utah's Great Salt Lake. The underlying aquifer has three confined or unconfined layers. Both embedding and response matrix (RM) approaches are tested and compared. Historically, it has been difficult to incorporate simulation of an unconfined aquifer and many external flow equations described by nonsmooth functions within linear programming models. RM models normally assume system linearity. The presented RM model overcomes this difficulty using cycling and influence coefficients generated with a modified MODFLOW model. In this groundwater flow simulation model, the above nonlinear terms …