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Civil and Environmental Engineering Faculty Publications

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Articles 421 - 450 of 562

Full-Text Articles in Civil and Environmental Engineering

Optimal System Design Of In-Situ Bioremediation Using Parallel Recombinative Simulated Annealing, Horng-Jer Shieh, Richard C. Peralta Jan 1997

Optimal System Design Of In-Situ Bioremediation Using Parallel Recombinative Simulated Annealing, Horng-Jer Shieh, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

We present a simulation/optimization model combining optimization with BIOPLUME II simulation for optimizing in-situ bioremediation system design. In-situ bioremediation of contaminated groundwater has become widely accepted because of its cost-effective ability to achieve satisfactory cleanup. We use parallel recombinative simulated annealing to search for an optimal design and apply the BIOPLUME II model to simulate aquifer hydraulics and bioremediation. Parallel recombinative simulated annealing is a general-purpose optimization approach that has the good convergence of simulated annealing and the efficient parallelization of a genetic algorithm. This is the first time that parallel recombinative simulated annealing has been applied to groundwater management. …


Optimal In-Situ Bioremediation System Design Using Parallel Recombinative Simulated Annealing, Horng-Jer Shieh, Richard C. Peralta Jan 1997

Optimal In-Situ Bioremediation System Design Using Parallel Recombinative Simulated Annealing, Horng-Jer Shieh, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Presented is a simulation/optimization (S/0) model combining optimization with BIOPLUME II simulation for optimizing in-situ bioremediation system design. The (S/0) model uses parallel recombinative simulated annealing to search for an optimal design and applies the BIOPLUME II model to simulate aquifer hydraulics and bioremediation. Parallel recombinative simulated annealing is a general-purpose optimization approach that has the good convergence of simulated annealing and the efficient parallelization of a genetic algorithm. We propose a two-stage management approach. The first stage design goal is to minimize total system cost (pumping/treatment, well installation and facility capital costs). The second stage design goal is to …


Preliminary Evaluation Of The Effects Of A Pumping Well On Existing Surface Water Resources Located In T. 12n, R. 2e, Sec. 23, Cache And Box Elder Counties, Denny J. Johnson, Richard C. Peralta Nov 1996

Preliminary Evaluation Of The Effects Of A Pumping Well On Existing Surface Water Resources Located In T. 12n, R. 2e, Sec. 23, Cache And Box Elder Counties, Denny J. Johnson, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

This report contains the results of a preliminary study of the impact of pumping a well located in T. 12N, R. 2E, sec. 23, Cache and Box Elder Counties, Utah. A semianalytical capture zone analysis was performed to determine if pumping at the well is likely to reduce flow in Willow Creek or any of three springs in the surrounding area. The well has been used from 1974 to present and is sometimes pumped at 90 gallons per minute (gpm) (verbal communication, Veibell, 1996).


On Hack's Law, Riccardo Rigon, Ignacio Rodriguez-Iturbe, Amos Maritan, Achille Giacometti, David G. Tarboton, Andrea Rinaldo Nov 1996

On Hack's Law, Riccardo Rigon, Ignacio Rodriguez-Iturbe, Amos Maritan, Achille Giacometti, David G. Tarboton, Andrea Rinaldo

Civil and Environmental Engineering Faculty Publications

Hack's law is reviewed, emphasizing its implications for the elongation of river basins as well as its connections with their fractal characteristics. The relation between Hack's law and the internal structure of river basins is investigated experimentally through digital elevation models. It is found that Hack's exponent, elongation, and some relevant fractal characters are closely related. The self-affine character of basin boundaries is shown to be connected to the power law decay of the probability of total contributing areas at any link and to Hack's law. An explanation for Hack's law is derived from scaling arguments. From the results we …


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.


A Spatially-Distributed Hydrologic Model For A Small Arid Mountain Watershed, Thomas H. Jackson, David G. Tarboton, Keith R. Cooley May 1996

A Spatially-Distributed Hydrologic Model For A Small Arid Mountain Watershed, Thomas H. Jackson, David G. Tarboton, Keith R. Cooley

Civil and Environmental Engineering Faculty Publications

A distributed water balance model was developed as a part of an intensive-field study to simulate the snowmelt-driven hydrologic response of a small mountain watershed using measured values of solar radiation, wind speed, air temperature, relative humidity and precipitation as input.

Snowmelt and evapotranspiration were modeled with point energy balances, written in terms of the snow surface and soil surface temperatures, respectively, corrected for local topographic characteristics and snow drifting. Meltwater was routed to the basin outlet as topography-driven, saturated subsurface flow, with all flow in excess of local transmissivity taken as surface runoff.

The model was calibrated with 1985-6 …


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


A Nonparametric Wet/Dry Spell Model For Resampling Daily Precipitation, Upmanu L. Lall, Balaji Rajagopalan, David G. Tarboton Apr 1996

A Nonparametric Wet/Dry Spell Model For Resampling Daily Precipitation, Upmanu L. Lall, Balaji Rajagopalan, David G. Tarboton

Civil and Environmental Engineering Faculty Publications

A nonparametric wet/dry spell model is developed for resampling daily precipitation at a site. The model considers alternating sequences of wet and dry days in a given season of the year. All marginal, joint, and conditional probability densities of interest (e.g., dry spell length, wet spell length, precipitation amount, and wet spell length given prior to dry spell length) are estimated nonparametrically using at-site data and kernel probability density estimators. Procedures for the disaggregation of wet spell precipitation into daily precipitation and for the generation of synthetic sequences are proffered. An application of the model for generating synthetic precipitation traces …


Effect Of Subsurface Heterogeneity On Free-Product Recovery From Unconfined Aquifers, Jagath J. Kaluarachchi Mar 1996

Effect Of Subsurface Heterogeneity On Free-Product Recovery From Unconfined Aquifers, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

Free-product record system designs for light-hydrocarbon-contaminated sites were investigated to evaluate the effects of subsurface heterogeneity using a vertically integrated three-phase flow model. The input stochastic variable of the areal flow analysis was the log-intrinsic permeability and it was generated using the Turning Band method. The results of a series of hypothetical field-scale simulations showed that subsurface heterogeneity has a substantial effect on free-product recovery predictions. As the heterogeneity increased, the recoverable oil volume decreased and the residual trapped oil volume increased. As the subsurface anisotropy increased, these effects together with free- and total-oil contaminated areas were further enhanced. The …


Optimal Pumping Strategies To Maximize Dissolved Tce Extraction At Mather Afb, California, Richard C. Peralta, Alaa H. Aly Mar 1996

Optimal Pumping Strategies To Maximize Dissolved Tce Extraction At Mather Afb, California, Richard C. Peralta, Alaa H. Aly

Civil and Environmental Engineering Faculty Publications

USU first estimated the future TCE concentrations that would result if no pumping strategy were implemented (Figure 5, Scenario AO). Then USU used the procedure of Appendix B with the model formulation of Appendix C to compute optimal pumping strategies. In computing optimal strategies USU cycled until an arbitrary three percent contaminant mass convergence criterion was satisfied.


Critical Assessment Of The Operator-Splitting Technique In Solving The Advection-Dispersion-Reaction Equation: 1. First-Order Reaction, Jagath J. Kaluarachchi, Jahangir Morshed Dec 1995

Critical Assessment Of The Operator-Splitting Technique In Solving The Advection-Dispersion-Reaction Equation: 1. First-Order Reaction, Jagath J. Kaluarachchi, Jahangir Morshed

Civil and Environmental Engineering Faculty Publications

Operator-splitting technique (OST) is a common mathematical approach used in the solution of the advection-dispersion-reaction equation (ADRE), especially in the presence of biological decay, where the scales of transport and biological decay are far apart. The OST introduces a time-lag between the advection-dispersion and reaction stages by splitting the ADRE causing a breakdown of the physics of the problem, thus limiting its applicability. In this work, the applicability of the operator splitting technique is studied in parts. This first manuscript addresses the critical limitations of the operator-splitting technique as related to first-order decay, and the second manuscript extends the work …


Critical Assessment Of The Operator-Splitting Technique In Solving The Advection-Dispersion-Reaction Equation: 2. Monod Kinetics And Coupled Transport, Jahangir Morshed, Jagath J. Kaluarachchi Dec 1995

Critical Assessment Of The Operator-Splitting Technique In Solving The Advection-Dispersion-Reaction Equation: 2. Monod Kinetics And Coupled Transport, Jahangir Morshed, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

In the first manuscript of this two-part series, the behavior of the inherent time-lag error in the operator-splitting technique has been discussed. However, the discussion has been limited to the advection-dispersion-reaction equation with first-order kinetics. In this manuscript, the discussion is extended to address the applicability of the operator-splitting technique in solving the advection-dispersion-reaction equation with Monod kinetics. The discussion also considers the two-species coupled transport problem. The results of the analysis show that the behavior of the time-lag error causing a mass balance error is rather similar to those observed with first-order kinetics. The time-lag error directly depends on …


Design Factors For Improving The Efficiency Of Freeproduct Recovery Systems In Unconfined Aquifers, Jagath J. Kaluarachchi, R. Elliot Nov 1995

Design Factors For Improving The Efficiency Of Freeproduct Recovery Systems In Unconfined Aquifers, Jagath J. Kaluarachchi, R. Elliot

Civil and Environmental Engineering Faculty Publications

Free-product recovery system designs for light hydrocarbon recovery were investigated to evaluate the effects of multiple-stage pumping, delayed startup, and uncertainty of key residual oil saturation input data using a vertically integrated three-phase flow model, ARMOS. The results obtained from a single well recovery system subjected to a given well location and uniform soil properties suggested that multiple-stage water pumping can enhance the recovery and provide optimal design conditions if cost and recovery oil volume are the targets. However, if containment of the spill area with simultaneous recovery is the target, then single-stage pumping still provides the optimal design. Delayed …


Optimal Pumping Strategies To Maximize Dissolved Tce Extraction At Central Base Area, Norton Afb, California, Richard C. Peralta Aug 1995

Optimal Pumping Strategies To Maximize Dissolved Tce Extraction At Central Base Area, Norton Afb, California, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Norton Air Force Base (NAFB) is located in the San Bernardino Valley, part of the California Peninsular Range geomorphic province (Figure 1). The elevation at NAFB is about 1,100 feet above mean sea level (msl). The ground slopes gradually to the southwest.


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 …


Preliminary Pumping Strategy Analyses For Southeastern Cache Valley, Utah And River Baseflow Impacts, Shyamal B. Chowdhury, Richard C. Peralta Apr 1995

Preliminary Pumping Strategy Analyses For Southeastern Cache Valley, Utah And River Baseflow Impacts, Shyamal B. Chowdhury, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

US/REMAX, a linear optimization model for groundwater management, is used to compute preliminary optimal sustained groundwater pumping increases for southeastern Cache Valley. US/REMAX employs the response matrix method of representing system response to stimuli as constraint equations within an optimization problem. The management objective is to maximize groundwater extraction at four specified locations subject to constrai~ts on aquifer potentiometric head, aquifer/river interflow, and the water level in the uppermost aquifer layer. Four scenarios (constraint sets) are presented. The results are most sensitive to the aquifer/river interflow constraints. Interflow is deemed important because baseflows are crucial to satisfying fish, aquatic life, …


Optimizing Irrigation Management For Pollution Control And Sustainable Crop Yield, Ghassan R. Musharrafieh, Richard C. Peralta, Lynn M. Dudley, Ronald J. Hanks Apr 1995

Optimizing Irrigation Management For Pollution Control And Sustainable Crop Yield, Ghassan R. Musharrafieh, Richard C. Peralta, Lynn M. Dudley, Ronald J. Hanks

Civil and Environmental Engineering Faculty Publications

Irrigation strategies which maximize crop yield while preventing salt from leaching to the groundwater or undesirable salt increases in the root zone are computed by using a one-dimensional simulation/optimization management model. The included constraint equations maintain a water volume balance and salt transport in the unsaturated zone. Implicit finite difference forms of the unsaturated water flow equation (Richards' equation), the diffusion-convection solute transport equation, functions describing the hydraulic properties of the medium, a root extraction function, and other constraints are used. The model uses a large discretization in time. A cyclic prediction and correction type of approach is adopted to …


Maximizing Tce Removal From A Contaminated Aquifer, Richard C. Peralta, Alaa H. Aly Apr 1995

Maximizing Tce Removal From A Contaminated Aquifer, Richard C. Peralta, Alaa H. Aly

Civil and Environmental Engineering Faculty Publications

A methodology for developing pumping strategies to maximize contaminant extraction is presented. The methodology consists of approximating the mass removal integral using a quadrature rule. Contaminant mass extraction is expressed as a function of the extraction rates. The relation of contaminant extraction to pumping rates is used as one of several constraints within a simulation/optimization model. The implementation and application of the methodology are described. The result is a set of pumping rates which are optimal in the sense that they maximize the mass of contaminant removed by the extraction system for a posed management scenario.


Us/Remax (Vs 2.70): Software For Optimizing Management Of Stream/Aquifer Systems Using The Response Matrix And Related Methods, Richard C. Peralta, Alaa H. Aly Apr 1995

Us/Remax (Vs 2.70): Software For Optimizing Management Of Stream/Aquifer Systems Using The Response Matrix And Related Methods, Richard C. Peralta, Alaa H. Aly

Civil and Environmental Engineering Faculty Publications

US/REMAX is designed to assist water managers in developing optimal groundwater and/or surface water strategies for a wide range of management problems. US/REMAX uses the response matrix method, which assumes that physical system response to stimuli is linear. However, US/REMAX can also address nonlinear systems via cycling. In one application, a strategy computed using US/REMAX required 40% less pumping than one obtained via a normal simulation model. US/REMAX also easily computes tradeoffs for multiobjective problems.


Modeling For Optimal Management Of Agricultural And Domestic Wastewater Loading To Streams, Muhammad Shafqat Ejaz, Richard C. Peralta Apr 1995

Modeling For Optimal Management Of Agricultural And Domestic Wastewater Loading To Streams, Muhammad Shafqat Ejaz, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

A simulation/optimization (S/0) model to aid managing multiobjective wastewater loading to streams while maintaining adequate downstream water quality is presented. The conflicting objectives are to maximize the human and dairy cattle populations from which treated wastewater can be discharged to the river system. Nonindustrial municipal (domestic) wastewater undergoes primary and secondary treatment by a sewage treatment plant (STP) before entering as a steady point source. Dairy wastewater is treated by overland flow (OLF) land treatment before entering the stream as a controlled steady diffuse source. Maximum dual-source loading strategies which do not degrade downstream water quality beyond specified limits are …


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 Pumping Strategy To Capture Tce Plume At Base Boundary, Norton Afb, California, Richard C. Peralta, A. H. Aly Jan 1995

Optimal Pumping Strategy To Capture Tce Plume At Base Boundary, Norton Afb, California, Richard C. Peralta, A. H. Aly

Civil and Environmental Engineering Faculty Publications

Ground water contaminated by trichloroethylene (TCE) at Norton AFB (NAFB) has reached off-base supply wells. Utah State University (USU) computed an optimal steady pumping strategy to eventually halt off-base migration of TCE exceeding 5 ppb. (A steady pumping strategy is a spatially distributed set of extraction and injection rates.)


Simplex Algorithm For Optimizing Drainage Design, Majid Ehteshami, Lyman S. Willardson, Richard C. Peralta Jan 1995

Simplex Algorithm For Optimizing Drainage Design, Majid Ehteshami, Lyman S. Willardson, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

A methodology and computer model is developed to determine economically optimum closed subsurface drainage systems in irrigated areas. The model maximizes net benefits, by comparing profit driven by crop yield to drain system cost and selects an optimum drain layout. The optimization methodology used, is the SIMPLEX method, Neider and Mead. The SIMPLEX model was linked to the subsurface drainage model DRAINMOD Skaggs [10], and to the surface hydraulic model KINE, Walker and Skogerboe[14]. The selected optimum drainage system maximizes the difference between total revenue, and the total cost of installation, operation and management of a particular drainage system. The …


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 …


Stepwise Pumping Approach To Improve Free Phase Light Hydrocarbon Recovery From Unconfined Aquifers, Grant Cooper, Richard C. Peralta, Jagath J. Kaluarachchi Jan 1995

Stepwise Pumping Approach To Improve Free Phase Light Hydrocarbon Recovery From Unconfined Aquifers, Grant Cooper, Richard C. Peralta, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

A stepwise, time-varying pumping approach is developed to improve free phase oil recovery of light non-aqueous phase liquids {LNAPL) from a homogeneous, unconfined aquifer. Stepwise pumping is used to contain the floating oil plume and obtain efficient free oil recovery. The pumping approach is developed using detailed simulations, multiple linear regression and graphical plots. The approach uses ARMOS©, an areal two-dimensional multiphase flow, finite-element simulation model. Systematic simulations of f~ oil area changes to pumping rates are analyzed. Pumping rates are determined that achieve LNAPL plume containment at different times (i.e. 90, 180 and 360 days) for a planning period …


Maximizing Conjunctive Use Of Surface And Ground Water Under Surface Water Quality Constraints, Muhammad Shafqat Ejaz, Richard C. Peralta Jan 1995

Maximizing Conjunctive Use Of Surface And Ground Water Under Surface Water Quality Constraints, Muhammad Shafqat Ejaz, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

A simulation/optimization (s/o) model is presented to address the increasingly common conflicts between water quantity and quality objectives. The model can assist water resources analysts in selecting compromise strategies for stream/aquifer systems in which the stream gains water from the aquifer. The water quantity objective is to maximize steady conjunctive use of groundwater and surface water resources. The water quality objective is to maximize waste loading from a sewage treatment plant {STP) to the stream without violating downstream water quality beyond acceptable limits. The STP discharge is proportional to human population. The two objectives conflict because an increase in groundwater …


Application Of Lawn Fertilizers And Pesticides In Salt Lake Valley Recharge Areas, Ghassan R. Musharrafieh, Larry Sager, Howard M. Deer, Richard C. Peralta Dec 1994

Application Of Lawn Fertilizers And Pesticides In Salt Lake Valley Recharge Areas, Ghassan R. Musharrafieh, Larry Sager, Howard M. Deer, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Homeowners, chemical applicators, and commercial lawncare companies apply chemicals to lawns and ornamentals overlying the recharge zone of Salt Lake Valley's principal aquifer. These applied fertilizers, herbicides, insecticides, and fungicides can potentially leach far enough to contaminate ground water. This report summarizes a study conducted in 1993-1994 to determine the type, rate, and frequency of applying chemicals to lawns and ornamentals in the recharge zone. Surveyed are lawncare companies, chemical applicators, schools, churches, hospitals, parks, homeowners, and government documents and community and state regulations. Results will help assess the potential impact of these applications on future ground water quality.


Modelling For Optimal Conjunctive Water Management: Irrigated Crop Production Versus Nps Pollution Prevention, O. H. Daza, Richard C. Peralta Nov 1994

Modelling For Optimal Conjunctive Water Management: Irrigated Crop Production Versus Nps Pollution Prevention, O. H. Daza, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Conjunctive water management{CWM)involves coordinating use of ground and surface water sources. Agricultural (A) and nonagricultural {NA)users compete for available water of adequate quality. A Simulation/Optimization (S/0) conjunctive water management model was developed to aid estimating the effects of water and environmental management decisions on crop yield and water quality. Included subsystems are groundwater, surface water, reservoir, delivery system, drainage, and A and NA water users. The nonlinear model addresses flows described by nonsmooth piecewise-linear functions which have discontinuous derivatives. Embedded constraints describe all significant subsystem flows. For example 1 deep percolation and runoff from surface irrigation are explicitly described as …


Conjunctive Management Of Surface Water And Ground Water Quantity And Quality: Conceptual And Functional Modelling Approach, Richard C. Peralta Jul 1994

Conjunctive Management Of Surface Water And Ground Water Quantity And Quality: Conceptual And Functional Modelling Approach, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

This report discusses how to design a computer model to aid optimizing conjunctive management of groundwater and surface water quantity and quality. The report does not present a completed computer model, but rather discusses how a future model could be developed. The discussed modelling approach is termed PROMOD (PROposed methodology and MODel). Precursors to PROMOD are in current use, but are far from having all the attributes discussed here. The additional capabilities are important to address world needs.


Integrated Embedding Optimization Applied To Salt Lake Valley Aquifers, A. Gharbi, Richard C. Peralta Mar 1994

Integrated Embedding Optimization Applied To Salt Lake Valley Aquifers, A. Gharbi, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

The embedding optimization modeling approach is adapted to aid sustainable groundwater quantity and quality management of complex nonlinear multilayer aquifers. Implicit block-centered finite difference approximations of the quasi three-dimensional unsteady flow equation and Galerkin finite element approximations of the two-dimensional advection-dispersion transport equation are embedded directly as constraints in the model. Also used are nonlinear constraints describing river-aquifer interflow, evapotranspiration, and vertical flow reduction due to unconfinement. These circumvent use of large numbers of integer variables. The use of both linear and nonlinear formulations in a cyclical manner reduces execution time and improves confidence in solution optimality. The methodology is …