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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.


Nonparametric Stochastic Generation Of Daily Precipitation And Other Weather Variables, Rajagopalan Balaji May 1995

Nonparametric Stochastic Generation Of Daily Precipitation And Other Weather Variables, Rajagopalan Balaji

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Traditional stochastic approaches for synthetic generation of weather variables often assume a prior functional form for the stochastic process, are often not capable of reproducing the probabilistic structure present in the data, and may not be uniformly applicable across sites. In an attempt to find a general framework for stochastic generation of weather variables, this study marks a unique departure from the traditional approaches, and ushers in the use of data-driven nonparametric techniques and demonstrates their utility.

Precipitation is one of the key variables that drive hydrologic systems and hence warrants more focus. In this regard, two major aspects of …


Evaluation Of Synthetic Unit Hydrograph Techniques For Utah Probable Maximum Flood Determinations, Ashraf Mohammed Shammet May 1995

Evaluation Of Synthetic Unit Hydrograph Techniques For Utah Probable Maximum Flood Determinations, Ashraf Mohammed Shammet

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Every dam must be capable of safely passing a predetermined flood magnitude. For high-hazard dams, it is a common practice to require that this flood be the Probable Maximum Flood (PMF). The determination of the PMF starts with the determination of the Probable Maximum Precipitation (PMP). We used the generalized estimates of the PMP as outlined in Hydrometeorological Report (HMR) 49. In this study we used the storm event model approach to convert the PMP into PMF. Different synthetic unit hydrograph (SUH) techniques were then used in the conversion process. The Soil Conservation Service (SCS) curve number method was used …


Spatial Variability And Error Limits Of Reference Evapotranspiration Estimates, Thomas W. Ley May 1995

Spatial Variability And Error Limits Of Reference Evapotranspiration Estimates, Thomas W. Ley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The overall objective of this research was to develop a methodology for assessing the spatial variability and error limits of reference evapotranspiration (ETr) estimates from a weather station network. Likely errors introduced into ETr estimates due to sensor measurement variability and nonstandard site conditions were investigated. Temporal and spatial correlation structures of the weather variables used to compute ETr and of ETr data collected over a three-year period by an operational agricultural weather station network were studied.

Results indicated that ETr errors are minimal compared to inherent model error when sensors (of the type …


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 …


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 …


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.


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, …


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 …


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.


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.


Proceedings Of The 1995 Annual Symposium On Engineering Geology And Geotechnical Engineering (No. 31), Joseph A. Caliendo Mar 1995

Proceedings Of The 1995 Annual Symposium On Engineering Geology And Geotechnical Engineering (No. 31), Joseph A. Caliendo

Reports

No abstract provided.


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 …


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.)


Locally Weighted Polynomial Regression: Parameter Choice And Application To Forecasts Of The Great Salt Lake, Upmanu Lall, Young-Ii Moon, Ken Bosworth Jan 1995

Locally Weighted Polynomial Regression: Parameter Choice And Application To Forecasts Of The Great Salt Lake, Upmanu Lall, Young-Ii Moon, Ken Bosworth

Reports

Relationships between hydrologic variables are often nonlinear. Usually the functional form of such a relationship is not known a priori. A multivariate, nonparametric regression methodology is provided here for approximating the underlying regression function using locally veighted polynomials. Locally weighted polynomials consider the approximation of the target function through a Taylor series expansion of the function in the neighborhood of the point of estimate. Cross validatory procedures for the selection of the size of the neighborhood over which this approximation should take place, and for the order of the local polynomial to use are provided and shown for some simple …


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 …


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 …