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Environmental Sciences

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Theses/Dissertations

1995

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The Relationship Between Environmental Attitudes And Environmental Behaviors Among Air Force Members, Daniel T. Holt Dec 1995

The Relationship Between Environmental Attitudes And Environmental Behaviors Among Air Force Members, Daniel T. Holt

Theses and Dissertations

A questionnaire was distributed to nearly 2,000 randomly selected active duty Air Force members assigned to locations throughout the continental United States. The survey was designed to determine the extent to which Air Force members expressed support for environmental issues. In addition, the survey measured how frequently Air Force members engaged in specific behaviors that were deemed environmentally protective. Although the Air Force members expressed relatively strong support for environmental issues, they only occasionally engaged in activities that contribute to the preservation or protection of the environment. Correlation analysis revealed that the pro-environmental attitudes were positively linked to the environmentally …


A Comparison Of Remediation Priorities Developed By The Defense Priority Model, The Relative Risk Evaluation Method, And A Quantitative Risk Assessment Approach, David M. Hunter Dec 1995

A Comparison Of Remediation Priorities Developed By The Defense Priority Model, The Relative Risk Evaluation Method, And A Quantitative Risk Assessment Approach, David M. Hunter

Theses and Dissertations

The Superfund, established by the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980, seriously underestimated both the number of severely contaminated sites and the associated cleanup cost. The magnitude of projected cleanup costs, coupled with shrinking federal budgets, necessitated the development and use of risk-based prioritization models among some federal agencies. Among these tools, the DOD prioritization models are meant to give priority to sites posing the greatest threat to human health. Their failure to properly rank sites could incorrectly shift the focus from those that pose substantial risk to sites of lesser risk. The DOD site ranking …


A Point Model Of Aquifer Cleanup With A Distribution Of First-Order Rate Parameters, Jon E. Hodge Dec 1995

A Point Model Of Aquifer Cleanup With A Distribution Of First-Order Rate Parameters, Jon E. Hodge

Theses and Dissertations

Many try modeling groundwater contaminant transport to predict it. Is this possible with rate-limited processes, and under what conditions? On occasion, cleanups go slower than predicted (tailing) and hazardous concentrations reappear after cleanup is thought complete (rebound). Rate-limited transport is blamed by many. When immobile water is present, diffusion from varied sizes and shapes of immobile regions can cause varied rate limitations (due to varied diffusion path lengths). Although known, most modelers represent these varied rate-limiting processes with a single 'representative' rate-parameter. This can yield poor predictions for long-term experiments, and the parameter is generally time and pump-rate dependent. This …


Geostatistical Analysis Of Hydraulic Conductivity In Heterogeneous Aquifers, Craig S. Biondo Dec 1995

Geostatistical Analysis Of Hydraulic Conductivity In Heterogeneous Aquifers, Craig S. Biondo

Theses and Dissertations

Observations of the spatial variability of hydraulic conductivity of the heterogeneous alluvial aquifer at Columbus Air Force Base in Mississippi are analyzed using parametric geostatistical approaches. Field studies have revealed that the heterogeneity of the aquifer hydraulic conductivity field controls the movement and dispersion of groundwater solutes. Therefore, a means of quantifying spatial variability is essential for the application of flow and solute transport models to practical problems. Application of these models requires a large number of hydraulic conductivity measurements. Geostatistical analysis and kriging estimation procedures assist in providing these large numbers of values when sampling designs have provided sparse …


Evaluating The Feasibility Of Sequential Indicator Simulation In Reproducing Spatial Connectivity In A Heterogeneous Transmissivity Field, D. Duane Kenyon Dec 1995

Evaluating The Feasibility Of Sequential Indicator Simulation In Reproducing Spatial Connectivity In A Heterogeneous Transmissivity Field, D. Duane Kenyon

Theses and Dissertations

A Non-Parametric estimation technique was used to simulate realizations of a heterogeneous transmissivity field based upon sampled values from three different sampling scenarios. These realizations were compared to output from a parametric estimation technique with respect to truth as defined by an exhaustive data set of 6,000 transmissivity values. Estimated transmissivity fields were then used as input into a flow model from which fields of heads and specific discharges were obtained and compared. Given the financial limitations imposed upon the number and quality of samples reasonably available, Sequential Indicator Simulation, a non-parametric technique, was shown to be of considerable value …


The Effects Of Vegetative Canopies On Atmospheric Dispersion, John R. Lindell Dec 1995

The Effects Of Vegetative Canopies On Atmospheric Dispersion, John R. Lindell

Theses and Dissertations

This research was conducted to improve our understanding of the effects of vegetative canopy-induced turbulence on the dispersion of air pollution. The computer model most often used to calculate atmospheric dispersion is the Gaussian plume model, which requires some method to compute the downwind dispersions coefficients. These coefficients are a parameterization of the atmospheric stability or the level of turbulence in the atmosphere. The Environmental Protection Agency's recommended parameterization scheme is the Pasquill-Gifford method. By comparing the Pasquill-Gifford method to the Modified Mitchell method using sigma theta, the standard deviation of the horizontal wind fluctuations, the relative precision of each …


Decision Support Model To Optimize Site Characterization Activities Taken In Compliance With The Comprehensive Environmental Response Compensation And Liability Act, Daniel J. Clairmont Dec 1995

Decision Support Model To Optimize Site Characterization Activities Taken In Compliance With The Comprehensive Environmental Response Compensation And Liability Act, Daniel J. Clairmont

Theses and Dissertations

One of the most frequently cited reasons for the slow and costly progress of Superfund cleanups is the remedial investigation and feasibility study process (RI/FS). After each phase of the RI/FS process there are several possible alternatives that may be chosen. This research developed decision support models to help decision makers choose between the feasible alternatives at five different decision points during site characterization activities. The models make recommendations on how to deal with any particular chemical based on the risk posed by that chemical. The models assume that the value of characterizing the site further is a reduction in …


Comparison Of Gravel Substrate Vs Soil Substrate For The Construction Of An Experimental Fen, Carolyn S. Langley Dec 1995

Comparison Of Gravel Substrate Vs Soil Substrate For The Construction Of An Experimental Fen, Carolyn S. Langley

Theses and Dissertations

Under the Clean Water Act Section 404 of 1972 and 33 CFR 320-330 and 40 CFR 230 moderate the destruction of wetlands by the Air Force to make way for other uses. To obtain a permit for a design or construction project which affects a wetland, the Air Force must agree to create new wetlands, or replace lost wetland acreage through wetland creation or restoration. The Air Force is interested in building 'successful' wetlands as inexpensively as possible. It has been common practice to use hydric soil, which often had to be hauled in, as the substrate at the restored …


A System Dynamics Approach To Modelling The Degradation Of Biochemical Oxygen Demand In A Constructed Wetland Receiving Stormwater Runoff, Leslie A. Mudgett Dec 1995

A System Dynamics Approach To Modelling The Degradation Of Biochemical Oxygen Demand In A Constructed Wetland Receiving Stormwater Runoff, Leslie A. Mudgett

Theses and Dissertations

The objective of this research was to develop a tool to aid the Air Force Environmental Manager in the identification of the design parameters of a constructed wetland system that may be optimized to provide a desired biochemical oxygen demand (BOD) removal efficiency during the treatment of Air Force stormwater runoff. The objective is achieved through the development and use of a system dynamics model which simulates the hydrological functions of a constructed wetland as well as the processes within the wetland responsible for degradation of BOD. Based on literature review, the primary mechanism responsible for the degradation of BOD …


A Comparison Of Response Surface Methodology And A One-Factor-At-A-Time Approach As Calibration Techniques For The Bioplume-Ii Simulation Model Of Contaminant Biodegradation, Benjamin Shuman Dec 1995

A Comparison Of Response Surface Methodology And A One-Factor-At-A-Time Approach As Calibration Techniques For The Bioplume-Ii Simulation Model Of Contaminant Biodegradation, Benjamin Shuman

Theses and Dissertations

This thesis compared Response Surface Methodology (RSM) to the one-factor-at-a-time approach for calibrating the Bioplume-II simulation model of contaminant biodegradation. The MADE-2 data set from Columbus Air Force Base, Mississippi was used. The one-factor-at-a-time approach reduced the root-mean-squared (RMS) error for the flow to 0.921225 feet in a total of 36 runs of Bioplume-II. The RSM approach reduced the error criterion to 0.918875 in a total of 47 runs. The one-factor-at-a-time approach was unable to reduce the error below 67.1831 parts per billion (ppb) after 21 runs. The RSM approach reduced the RMS error to 67.0327 ppb after 47 runs. …


The Effect Of Sulfur And Phosphorus Compounds On Supported Platinum Catalyst Activity, Yi Wang Oct 1995

The Effect Of Sulfur And Phosphorus Compounds On Supported Platinum Catalyst Activity, Yi Wang

Dissertations

The effect of sulfur poisoning on the activity of catalysts containing 1.5% platinum supported on γ-Al2O3, TiO2, ZrO2, or SiO2 was investigated in this study. These four catalysts were aged with 100 ppmv H2S in air at 400°C for 24 hours to determine the effect of sulfur poisoning under oxidizing conditions. In separate experiments, 1.5% Pt/γ-Al2O3 catalyst was aged in nitrogen containing 100 ppmv H2S to obtain a frame of reference for non-oxidizing conditions.

The oxidation of 1% CO, 1% methane, and 1% propane …


Investigation Into Fracture Behavior And Longevity Of Pneumatically Fractured Fine-Grained Formations, Heathe Ann Hall Oct 1995

Investigation Into Fracture Behavior And Longevity Of Pneumatically Fractured Fine-Grained Formations, Heathe Ann Hall

Theses

This study investigates volume changes in fine-grained soil formations and their effect on pneumatically induced fractures. Pneumatic fracturing is an enhancement technology for in situ remediation of hazardous waste sites, which increases the formation permeability by creating fractures. A number of formation properties and environmental conditions which affect fracture aperture were identified in this study.

Laboratory experiments were performed with control devices to investigate idealized fracture flow under linear and radial flow geometries. These tests exhibited cubic law behavior, and gas compressibility was seen as a measurable effect. A horizontal infiltrometer device was successfully developed to induce and control volume …


Catalytic Oxidation Of Trace Concentrations Of Trichloroethylene Over Cr2o3 And 5% Cr2o3 On ?-Al2o3, Soyoung Myung Oct 1995

Catalytic Oxidation Of Trace Concentrations Of Trichloroethylene Over Cr2o3 And 5% Cr2o3 On ?-Al2o3, Soyoung Myung

Theses

This research addressed the ability of Cr2O3 and 5% Cr2O3/γ-Al2O3 to catalytically oxidize trichioroethylene (TCE). Various types of Cr2O3 catalysts were compared with Pt, CuO and Fe2O3 which were previously tested in our laboratory. A number of sample catalysts containing 5% Cr2O3 on γ-Al2O3 were synthesized for this research. Different procedures were evaluated in the synthesis in order to find which procedure gives the most active catalyst. The oxidation of TCE was used as a diagnostic reaction to …


Effectiveness Of Sediment Control Structure : Reducing Nonpoint-Source Pollution Entering A Rural Housing Development Lake In Mercer County, Pennsylvania, Elaine K. Brenner Oct 1995

Effectiveness Of Sediment Control Structure : Reducing Nonpoint-Source Pollution Entering A Rural Housing Development Lake In Mercer County, Pennsylvania, Elaine K. Brenner

Theses

For the past two decades, water quality of both natural and man-made lakes has been a major environmental concern. Numerous studies suggest that land use patterns and/or storm water runoff are major factors in nutrient loading and bacterial contamination of freshwater lakes. In 1986, the Property Owners Association at Lake Latonka in Jackson Center, Pa., installed three sediment control structures in an attempt to reduce the amount of nonpoint-source pollution entering the lake. The Association installed a fourth structure in 1988. It has yet to be determined if any improvement in the water quality has occurred due to the control …


Ultrasonic Enhanced Soil Washing, Chu-Feng Wei Oct 1995

Ultrasonic Enhanced Soil Washing, Chu-Feng Wei

Theses

Soil washing is an ex-situ process employing chemical and physical extraction and separation techniques to remove a broad range of organic, inorganic, and radioactive contaminants from soils. This research investigates the enhanced soil washing of a high level Polycyclic Aromatic Hydrocarbons (PAHs) contaminated coal tar soil by the application of ultrasound energy coupled with surfactant (soap) emulsions and attempts to optimize pollutant removal from contaminated soils. The non-ionic surfactant, octyl-phenyl-ethoxylate, was used as the surfactant.

Using bench-scale experiments, the magnitude of the ultrasonic enhancement was evaluated by changing the process parameters, such as ultrasonic power density, Dwell (extractor residence time), …


Management Of Pesticide Related Soil Contamination In Tulare County, California: Remediation And Prevention Options, Nickolas Keoni Akana Oct 1995

Management Of Pesticide Related Soil Contamination In Tulare County, California: Remediation And Prevention Options, Nickolas Keoni Akana

UNLV Theses, Dissertations, Professional Papers, and Capstones

The case study chosen for research is the Remedial Action Plan (RAP) summary report of Remedial Investigations of the Harmon Field contaminated site located near the town of Pixley, in Tulare County, California. "These reports were prepared in accordance with a directive from the California Environmental Protection Agency (Cal-EPA), formerly the California Department of Health Services (DHS). (Canonie, 1996).

Harmon Field is a hundred acre field located at 1494 South Airport Road. The airfield has been in full operation since 1952. The uses of the airport are all agriculturally related. The primary use is for crop duster operations. (Canonie 1996). …


Zooplankton Community Dynamics In The Elizabeth River, Virginia, William C. Sharp Jul 1995

Zooplankton Community Dynamics In The Elizabeth River, Virginia, William C. Sharp

Biological Sciences Theses & Dissertations

Zooplankton community structure and dynamics were studied over a 12 month period in the Elizabeth River, an industrially polluted tidal river in the Chesapeake Bay estuarine system. An additional site in this estuary (Hampton Roads) was sampled for comparative purposes. Multivariate analysis indicated five distinct temporal groups occurred during the year, but there were no significant differences in spatial composition within the river. Maximum zooplankton concentrations were observed in July and lowest abundances were observed in February, March, and November. Copepods, especially Acartia species, were the most abundant components of the zooplankton community, comprising 67 to 93% of the total …


Epidemiological Study Of Road Traffic Accidents, Casualties And Fatalities In The United Arab Emirates, Ahmed Saif Al-Falasi Jun 1995

Epidemiological Study Of Road Traffic Accidents, Casualties And Fatalities In The United Arab Emirates, Ahmed Saif Al-Falasi

Theses

In the United Arab Emirates (UAE), with its rapid expansion of road construction and increase in the number of vehicle, road traffic accidents are becoming a serious public health problem. It was aimed to study road traffic accidents (RTA) in view of the fact that cause a substantial waste of national resources which could be used fruitfully for the improvement of health schemes and other aspects of life in UAE. It was observed that there has been a dramatic increase in the number of registered vehicles during this period. During the ten years period 1983 to 1992, the population of …


Heavy Minerals And Metals Content Of Coastal Sediments Between Dibba And Kalba, Eastern Coast (U.A.E.)., Aisha Hader Juma Jun 1995

Heavy Minerals And Metals Content Of Coastal Sediments Between Dibba And Kalba, Eastern Coast (U.A.E.)., Aisha Hader Juma

Theses

The present project deals with the study of coastal sediments along the Eastern Coast of United Arab Emirates (U.A.E.), and it has two main objectives:

  • Determination of heavy mineral contents of the coastal sediments in relation to the geology of the hinterlands.
  • Trace metals studies (Zn, Pb, Ni, Cr, Cu, Co, Cd, Mn and organic carbon) as a measure of environmental pollution.

The results of heavy minerals separation (fine sand fraction) from the Eastern Coast sediments reflect that these sediments are generally rich in heavy minerals content with percentages reaching up to 78% with some areas reaching upto 98%. The …


Management Of Hospital Wastes In The United Arab Emirates, Hanan Ahmed Ali Shuwaiter Jun 1995

Management Of Hospital Wastes In The United Arab Emirates, Hanan Ahmed Ali Shuwaiter

Theses

The gradual expansion and development of new public and private medical complexes have resulted in the production of various types of wastes which include hazardous materials. Such wastes require appropriate handling and management schemes based on safer disposal methods. There are no reliable figures for quantifying the amount of medical waste generated or appropriate legislation and guidelines for handling, storage, transport and disposal of medical waste in the United Arab Emirates. No previous detailed studies have been conducted for the management of medical waste in the UAE. In general there is insufficient awareness of the health hazard associated with improper …


Dichloromethane Pyrolysis And Oxidation : Formation Of Chlorinated Aromatic Precursors To Pcdd/F, Hong-Ming Chiang May 1995

Dichloromethane Pyrolysis And Oxidation : Formation Of Chlorinated Aromatic Precursors To Pcdd/F, Hong-Ming Chiang

Dissertations

The pyrolysis and oxidation of dichloromethane is studied in a tubular reactor at 1 atmosphere pressure, residence time between 0.3 to 2.0 seconds and in the temperature range 680 - 840°T. Four reactant concentration ratios are:
I. CH2Cl2 : Ar =1 : 99 II. CH2Cl2 : CH4 : Ar = 1 : 1:98
III.CH2Cl2 : O2 : Ar = 1:4 : 95 IV. CH2Cl2: CH4 : O2 Ar = 1: 4: 94

The degradation of dichloromethane, intermediate product formation and decomposition, and final …


Analysis Of The Oxidation Of Isotox By Immobilized Bacteria, Chad Sheng May 1995

Analysis Of The Oxidation Of Isotox By Immobilized Bacteria, Chad Sheng

Theses

The purpose of this work is to show the effects of bio-oxidation of a pesticide through a spiral wound bioreactor using immobilized mixed culture bacteria. The pesticide used for this study is Isotox® and its active ingredients are acephate or O,S-dimethyl acetylphosphoramidothioate and vendex or hexakis (2-methyl-2-phenylpropyI)- distannoxane. Qualitative analysis of the product indicated presence of sulfate.

A consistent and unique DO pattern for Isotox® showed at least 4 minima, whereas phenol has only one minimum. The consistency of the DO pattern for Isotox® has been observed for over 30 injections into the bioreactor system. For both an …


Transitions In Masculinity And Hemingway's Developed "Code", Daniel Polk May 1995

Transitions In Masculinity And Hemingway's Developed "Code", Daniel Polk

Honors Theses

The "Hemingway Code" is much more than two words that fit nicely together for a scholar's usage; the words signify a much deeper championing of masculinity, almost a haunting presence. For Ernest Hemingway living life every day, every moment with its fullest masculine fervor, became an obsession, a never-ending quest to be at one with the attitude of never complaining, never crying out, panicking, thinking too much, or regretting. To live a manly life in a series of tactical victories, performed with steadfast ritualistic mannerisms, is to embody masculinity, and therefore the "Hemingway Code."


Disease And Habitat Change As Factors Associated With Mourning Dove Population Decline, William D. Ostrand May 1995

Disease And Habitat Change As Factors Associated With Mourning Dove Population Decline, William D. Ostrand

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The western mourning dove (Zenaida macroura) population has been declining since 1966. Data collected in 1951-52, in Fillmore, Utah, provided us a baseline for comparison with our study in the same area. Our approach was to determine whether a local population decline had occurred since the original data were collected, assess if trichomoniasis has impacted the local population, determine if changes in habitat structure affect foraging site selection, quantify changes in habitat, identify which habitats doves preferred, ascertain whether doves had responded to habitat change by changing food habits, and assess if changes in habitat were responsible in …


Behavioral Characteristics Affect Habitat Selection Of Domestic Ruminants, Cody B. Scott May 1995

Behavioral Characteristics Affect Habitat Selection Of Domestic Ruminants, Cody B. Scott

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I evaluated some of the factors affecting livestock distribution by conducting experimental (Chapters II and III) and observational (Chapter IV) studies. In Chapter II, I described the effect of locations of familiar foods and social interactions on choice of feeding location by lambs. Lambs were exposed to a pasture as subgroups of strangers and companions with different dietary habits (i.e., three lambs that preferred milo with three lambs that preferred wheat). Milo was placed on one end and wheat on the other, about 100 m apart. Strangers typically fed in different locations, reflecting dietary preferences. Conversely, companions fed in both …


Competitive Interactions Between Two Closely Related Rhizomatous And Caespitose Perennial Grasses Under Varying Conditions, L. David Humphrey May 1995

Competitive Interactions Between Two Closely Related Rhizomatous And Caespitose Perennial Grasses Under Varying Conditions, L. David Humphrey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Biomass, tiller numbers, flowering, and genet survival were accessed for the rhizomatous Elymus lanceolatus ssp. lanceolatus and caespitose E. l. ssp. wawawaiensis growing in mixtures with a range of densities of each taxon. Models of aboveground biomass of each taxon as a function of mixed densities were used to calculate competition indices. Tiller numbers and biomass of ssp. lanceolatus were higher than those of the caespitose taxon in the first year, but declined in the second year, while biomass and tiller numbers of ssp. wawawaiensis changed little. All tillers of ssp. wawawaiensis emerged in autumn; tillers of ssp. …


Evaluation Of Lake Fertilization As A Tool To Assist In The Recovery Of The Snake River Sockeye Salmon (Oncorhynchus Nerka), Howard P. Gross May 1995

Evaluation Of Lake Fertilization As A Tool To Assist In The Recovery Of The Snake River Sockeye Salmon (Oncorhynchus Nerka), Howard P. Gross

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I analyzed lake fertilization (with nitrogen and phosphorus) as a tool to assist in the recovery of the Snake River sockeye salmon (Oncorhynchus nerka) in the oligotrophic Sawtooth Valley Lakes in southcentral Idaho. These analyses involved monitoring, manipulating, and modelling several aspects of the lakes' primary producer, nutrient, and light parameters.

In Pettit Lake, I evaluated the effects of metalimnetic and epilimnetic fertilization in 330-m3 mesocosms. The metalimnetic treatment was equal to or more effective than the epilimnetic treatment in increasing chlorophyll a, phytoplankton biovolume, and primary productivity, yet caused smaller changes in periphyton growth and …


Winter Habitat Selection By American Marten (Martes Americana) In Newfoundland: Why Old Growth?, Gary S. Drew May 1995

Winter Habitat Selection By American Marten (Martes Americana) In Newfoundland: Why Old Growth?, Gary S. Drew

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although the American marten (Martes americana) generally is recognized as an obligate late-seral species, the factors dictating this association are poorly understood. Martens were studied in Newfoundland, Yellowstone National Park, and in a captive setting. As expected, use of habitat types was not proportional to availability P < 0.001). Defoliated and late-seral conifer stands were used more than expected, while all other types indicated expected or less than expected use. Habitat selection by martens was detectable at spatial scales greater than 80 m (P < 0.001).

Newfoundland martens were radio-collared and monitored for diet activity during the winters of 1990 and 1991. A regression of the percent active fixes on temperature had a negative slope (b = -4.45, P = 0.084, n = 12), indicating that martens did not minimize their exposure to low temperatures. A log-linear model suggested …


Updating The Colorado River Compact, Jeffrey A. Freer Apr 1995

Updating The Colorado River Compact, Jeffrey A. Freer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Water is essential to life in the arid environment of the western United States. For centuries, humans have used the Colorado River to fulfill their needs and until the past 100 years, the use of the river was sustainable. Over the last 100 years, the Colorado River has been dammed and diverted to "reclaim" the arid west for man's use. In 1946, a Department of the Interior report stated that "Tomorrow the Colorado will be utilized to the very last drop. Its water will convert thousands of additional acres of sagebrush desert to flourishing farms and beautiful homes for servicemen, …


Limiting Growth In Las Vegas - A Necessary Growth Strategy For The Twenty-First Century, Cheryl Ann Frassa Apr 1995

Limiting Growth In Las Vegas - A Necessary Growth Strategy For The Twenty-First Century, Cheryl Ann Frassa

UNLV Theses, Dissertations, Professional Papers, and Capstones

Land development in the Las Vegas Valley continues at an unprecedented rate and future growth will no doubt be strongly advocated. Yet, water resources in this desert area are finite, and in the near future, supply will fall short of demand. Plans are underway to supplement the existing supply, and proposals to secure additional sources are under investigation. But there are no guarantees these ambitious endeavors will materialize. In light of the pending water crisis, the pervasive "growth at all cost" policies now dominant in the valley must be abandoned and more realistic land-use policies developed; ones based on the …