Engineering Commons^™

Quantitative Validation Of A Model Of Chlorinated Ethene Natural Attenuation, Harold C. Young

Theses and Dissertations

Chlorinated ethenes are among the most prevalent groundwater contaminants at hazardous waste sites nationwide. In an attempt to manage the risks posed by these contaminants, while controlling costs, monitored natural attenuation (MNA) is being considered as a remediation strategy at many sites. MNA relies on naturally occurring physical, chemical, and biological processes in the subsurface to reduce the risk posed by the contamination. The implementation of MNA, however, requires a detailed understanding of these processes, and how they impact contamination at a particular site. One way to gain this understanding is through contaminant fate and transport modeling. In this study, …

Determining The Value Of Groundwater Contamination Source Removal: A Methodology, Benjamin C. Recker

Theses and Dissertations

Subsurface contamination by industrial chemicals is one of the most prevalent and costly environmental problems facing the United States government. This contamination problem must be managed to protect human health and the environment. Two basic strategies are used to deal with subsurface contamination: source removal and contaminant containment. While much cost and performance data are available for individual technologies associated with each of these strategies, there have been very few studies that have examined the benefits of implementing source removal technologies in order to reduce contaminant containment (and hopefully total) costs. This study examines the tradeoff between extent of source …

Modeling Chlorinated Ethene Removal In The Methanogenic Zone Of Constructed Wetlands: A System Dynamics Approach, Randall L. Roberts

Theses and Dissertations

The purpose of this study is to gain understanding of the dynamics of the processes that degrade Perchloroethene (PCE) to ethene, within the confines of the methanogenic zone of a constructed wetland. A system dynamics modeling approach is used. This model is focused on determining conditions that will enhance contaminant degradation. The chemical and biological processes within the methanogenic zone of a wetland system are extremely complex and dynamic processes. The model is broken up into three simultaneous processes: dechlorination, methanogenesis, and fermentation. The system behavior of the methanogenic zone can be adequately described by the classical formulations of representative …

Assessing The Economic Impact Of Aircraft Noise On Communities, Ithan B. Zimmer

Dissertations

The impact of aircraft noise on communities is complex and multi-dimensional. This matter cannot be resolved without careful analysis of a complex array of related problems and issues including the environment, the economy, and quality-of-life concerns of people living in proximity to airports or aircraft routes. The effects of community noise are widespread and varied. Impacts can include sleep and speech interference, activity interference, general annoyance, and property value decrease. In order to improve public policy and provide a foundation for additional research, it is imperative to establish the extent of a problem. Dollars are often the least common denominator …

Development And Application Of A Computer Simulation Tool For Ecological Risk Assessments, Haiyi Lu

Theses

In an effort to improve tools in ecological risk assessment (ERA), an ERA software tool was developed and applied. Based on a preliminary evaluation of existing ecorisk models, the relative deficiencies were identified and included the need for a user-friendly interface, an interactive database management system (DBMS), and a comprehensive evaluation of exposure pathways. In this research, Visual Basic (VB) 6.0 and Microsoft SQL server were selected for developing the Windows-based interface and local DBMS, respectively. For the exposure estimate, Yuma and Aberdeen Proving Grounds were identified as baseline ecosystems. Terrestrial and aquatic plant and animal receptor selection was based …

Optimization Of Nitrogen Removal In Sequencing Batch Reactor, Suppakit Poonyachat

Theses

Operating parameters for sequencing batch reactor have the influenceon each substrate concentration. Concentration profile changes as operationparameters are changed. The study was conducted to model the variationin effluent concentration from sequencing batch reactor. MLVSS and cycletime are the parameters that were varied. Concentration in Fill, React,and Settle Period were calculated by using kinetic equations.

The results can show that these parameters have effects on the concentrationprofile. The increase of MLVSS can lower the concentration of BOD andammonium concentration in React period. Increasing MLVSS can show thatmore substrate utilization and nitrification process occur more rapidly.Concentration of nitrate at the end of …

Webquests As An Integrative Experience In Introductory Environmental Engineering, Mary P. Cardenas

All HMC Faculty Publications and Research

An Integrative Experience was developed as part of an introductory environmental engineering course at Harvey Mudd College. The Integrative Experience was developed to help the college students consider the relationship of science and technology with contemporary society. Junior and senior students enrolled in the course designed WebQuests for middle school students. The WebQuests involved the integration of an environmental issue, problem, or technology and societal effects. WebQuests were designed for a middle school audience in order to expand the amount of engineering outreach that is done at the K-12 level. The HMC students chose WebQuests topics including nuclear and alternative …

Estimation Of Reference Crop Evapotranspiration Using Fuzzy State Models, Lameck O. Odhiambo, R. E. Yoder, D. C. Yoder

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Daily evapotranspiration (ET) rates are needed for irrigation scheduling. Owing to the difficulty of obtaining accurate field measurements, ET rates are commonly estimated from weather parameters. A few empirical or semi–empirical methods have been developed for assessing daily reference crop ET, which is converted to actual crop ET using crop coefficients. The FAO Penman–Monteith method, which is now accepted as the standard method for the computation of daily reference ET, is sophisticated. It requires several input parameters, some of which have no actual measurements but are estimated from measured weather parameters. In this study, we examined the suitability of fuzzy …

Optimization Of Fuzzy Evapotranspiration Model Through Neural Training With Input–Output Examples, Lameck O. Odhiambo, R. E. Yoder, D. C. Yoder, J. W. Hines

Department of Agricultural and Biological Systems Engineering: Faculty Publications

In a previous study, we demonstrated that fuzzy evapotranspiration (ET) models can achieve accurate estimation of daily ET comparable to the FAO Penman–Monteith equation, and showed the advantages of the fuzzy approach over other methods. The estimation accuracy of the fuzzy models, however, depended on the shape of the membership functions and the control rules built by trial–and–error methods. This paper shows how the trial and error drawback is eliminated with the application of a fuzzy–neural system, which combines the advantages of fuzzy logic (FL) and artificial neural networks (ANN). The strategy consisted of fusing the FL and ANN on …

Studies On The Pollution Parameters Of Leachate From Ampang Landfill, Syed Fatimah Kamal Batcha

Student Works (2000-2009)

ln the first part of the study, the characteristics of the leachate from Ampang landfill, collected before and after the landfill closure was analysed. In general, the characteristics of the Ampang landfill leachate was found to be typical of other landfill leachates in the Klang Valley. The analysis reveals that the Ampang landfill leachate during its active life had high contents of sodium, potassium, chloride and ferum, with concentrations of 687 ppm, 785 ppm, 2500 ppm and 45 ppm respectively. Generally and as expected, the leachate collected before the landfiII closure was found to be more concentrated and contains more …

Assessing Methodologies For Identification Of Significant Impacts In The Iso 14001 Ems (Environmental Management Systems), Ann Wye-Wye Wang

Student Works (2000-2009)

ISO 14001 is a voluntary environmental management system specification standard in the ISO 14000 series. It contains those elements that must be satisfied by an organisation seeking registration or certification to the standard. Identification of significant environmental impacts is one of the requirements as stated in clause 4.3.1 of MS ISO 14001 EMS - specification with guidance for use, and is an important step in the implementation of ISO 14001 standard. A study on the methodologies for identification of significant environmental impacts in the ISO 14001 EMS (Environmental Management Systems) was carried out. Three methods that have been developed are …

Development Of A Physico-Chemical Wastewater Treatment Strategy For A Chemical Plant, T. Alagarajah K. Thavarajah

Student Works (2000-2009)

A study was carried out to determine the physico-chemical treatment of the wastewater collected from a soap and detergent factory in Selangor, Malaysia. The study was initiated by determining the characteristics of the wastewater. Treatability studies involving coagulation and flocculation were determined by the jar test method. The parameters of interest were coagulant dosage, pH, mixing intensity, mixing time and settling time. The coagulants were restricted to alum and ferric sulfate and coagulant aids utilized were polyvinyl alcohol, sodium alginate and polycthylcninimine. An extended evaluation to determine the effect of double chemical treatment was also carried out with the most …

Comparative Performance Of Wastewater Treatment Plants In Three Rubber Glove Manufacturing Plants, Lee Kuan Loh

Student Works (2000-2009)

During the manufacturing of rubber gloves, water is used as wash water at different stages to clean the rubber gloves, thus generating quite a substantial amount of effluent. There are four main sources of effluent. i.e. a) from the glove formers cleaning tank, which collects the acidified water used to clean these formers, b) latex dipping tank, where it collects wash water used to cool the tank during dipping process and the sludge form the tank itself, c) leaching tank, where it collects wash water used to leach out the pollutants from the gloves and lastly d) latex compounding, containing …

Waste Management In Palm-Oleo Sdn. Bhd, Ramesh Ramasamy

Student Works (2000-2009)

Oleochemical industry in Malaysia has been diversifying significantly due to the availability of raw materials (palm oil) and the high demand for downstream products such as fatty acids, fatty alcohols and glycerine. The growth of oleochemical industries is further enhanced by fluctuations io petroleum price and regular animal diseases, which made tallow-based fats unreliable. Environmental awareness is growing rapidly in Malaysia. There is growing realization of the need to balance industrial and economic development with environmental preservation and protection, as well as, with efficient use of energy sources in order to achieve sustainable development. Extensive waste management studies were focused …

Performance Comparison Of A Roundabout Versus Two-Way Stop Controlled (Twsc) Intersections, Deogratias Eustace

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

The superior safety record of modern roundabouts is well known in Western Europe, Australia and in most British-influenced countries around the world. The experience from a single modern roundabout installed in the City of Manhattan, Kansas, some three years ago, also shares the same experience. A major study of the performance of Manhattan, Kansas, modern roundabout was conducted at Kansas State University (KSU) and was co-sponsored by Mac-Blackwell National Rural Transportation Study Center, Kansas State University, and the City of Manhattan. The study examined three intersections, one modern roundabout and two Two-Way Stop Controlled (TWSC) intersections with similar traffic conditions. …

Alternative Principal Components Regression Procedures For Dendrohydrologic Reconstructions, Hugo G. Hidalgo, Thomas C. Piechota, John A. Dracup

Civil and Environmental Engineering and Construction Faculty Research

Streamflow reconstruction using tree ring information (dendrohydrology) has traditionally used principal components analysis (PCA) and stepwise regression to form a transfer function. However, PCA has several procedural choices that may result in very different reconstructions. This study assesses the different procedures in PCA-based regression and suggests alternative procedures for selection of variables and principal components. Cross-validation statistics are presented as an alternative for independently testing and identifying the optimal model. The objective is to use these statistics as a measure of the model's performance to find a conceptually acceptable model with a low prediction error and the fewest number of …

Environmental Evaluation Of Incinerators In Egypt & Waste Management Of Ash, Aya Mohamed Lamei

Archived Theses and Dissertations

No abstract provided.

Validation Of Passive Air Sampling Monitors Onboard United States Navy Submarines, Larry A. Mcfarland

Community & Environmental Health Theses & Dissertations

An operating submarine creates a unique air quality mixture of compounds that result from a combination of human metabolism, construction materials, materials brought onboard and compounds created through the interaction of ship systems. A comprehensive study of submarine atmospheres is ongoing during deployments of U.S. Navy nuclear submarines. As part of the overall effort, a paired air sampling comparison field validation was conducted to compare the air sampling effectiveness of passive diffusive monitors compared to more traditional active air sampling methods when sampling for acrolein, formaldehyde and ozone in the enclosed submarine atmosphere. Acrolein monitors containing 2-hydroxymethylpiperidine (HMP) impregnated glass …

Towards Quantification Of Active Sand Volume In The Nearshore Profile, Sukru Serkan Ozger

Civil & Environmental Engineering Theses & Dissertations

An active sand volume concept is introduced for the first time in this study. The significance of this new concept and its possible practical uses for Coastal Engineering are discussed. A theory is proposed towards quantification of the active sand volume across a beach profile and the circumstances under which it should be defined are determined.

Next, a 12-year nearshore bathymetric data set surveyed at the Field Research Facility of the Army Corps of Engineers at Duck, NC is used to determine the hypothetical quantity of active volume. Statistical analysis of elevations at digitized cross-shore distances is performed and a …

A Buffered Advection/Dispersion Lake Water Quality Transport Framework For Modeling Lake Gaston Pipeline Intake Water Withdrawal, Lloyd Ashton Gatling

Civil & Environmental Engineering Theses & Dissertations

Water quality response to reservoir water withdrawal is investigated in Pea Hill Arm of Lake Gaston, a non-tidal reservoir tributary, where the point of water withdrawal is in an upstream tributary and influences the direction of tributary flow causing longitudinal velocity null flow conditions to occur. The study also focuses on control of withdrawal rate and timing to optimize both quality of water remaining in the tributary and quantity of water that can be safely withdrawn.

Research was conducted assuming steady state conditions and later under spatial and temporal variability experienced in the reservoir with main lake pool elevation fluctuations …

In Situ Treatment Of Chlorinated Ethene-Contaminated Groundwater Using Horizontal Flow Treatment Wells, Derek R. Ferland

Theses and Dissertations

The limitations of conventional containment technologies for groundwater contaminated with chlorinated solvents have motivated development of innovative technologies to achieve national groundwater remediation objectives. One inn9vative technology that is currently under development involves metal reductants or catalysts to chemically destroy the dissolved chlorinated solvent. Models are important tools that can be used to help transition this technology to the field. Model studies can be used to gain understanding about the technology, help determine when the prospective technology might work for a given site, and design full-scale field applications.

Modeling The Effect Of Nonlinear And Rate-Limited Sorption On The Natural Attenuation Of Chlorinated Ethenes, Peter P. Feng

Theses and Dissertations

Chlorinated solvents like tetrachloroethene (PCE) and trichloroethene (TCE) are the most common detected groundwater contaminants at Department of Defense installations in the United States. Unfortunately, technologies conventionally used to remediate chlorinated solvent-contaminated groundwater often fall short of achieving regulatory goals. Natural attenuation of chlorinated solvents offers an alternative remediation strategy that may achieve goals. However, the processes involved with natural attenuation are not fully understood, and this lack of understanding has hindered acceptance of natural attenuation by regulatory agencies. This study involved use of a numerical model that incorporated the physical, chemical, and biological processes thought to be relevant to …

Use Of Genetic Algorithms To Characterize Groundwater Contamination Source Areas, Chaz M. Williamson

Theses and Dissertations

In this work, genetic algorithms (GAs) were used to help interpret tracer breakthrough curves from partitioning interwell tracer tests (PITTs) conducted at Hill AFB, Utah by researchers from the University of Florida. Two transport models were developed to simulate tracer transport in the test cells. One model assumed the cell consisted of multiple layers, and that transport in each layer could he described by the one-dimensional advective/dispersive equation. The second model also assumed multiple layers, and modeled transport in the individual layers as advective transport through 100 tubes. Transport times were represented by a stochastic (lognormal) distribution. The model solutions …

Effects Of Moisture Content In Solid Waste Landfills, Craig P. Eck

Theses and Dissertations

Solid waste landfills are an extremely complex and heterogeneous environment. Modeling the biodegradation processes within a landfill must involve an understanding of how environmental factors affect these processes. Arguably, the most important environmental factor influencing biodegradation processes is solid waste moisture content. This research effort, which is an extension of a system dynamics model previously presented by Colborn (1997) and amended by Benter (1999), attempts to understand and model the effects of moisture content on waste degradation and landfill gas generation. The new moisture structure that was added to the previous models provides a better representation of the impact of …

Final Environmental Impact Statement - Iron Point Exploraton License - Iron Point Coal Lease Tract - Elk Creek Coal Lease Tract, Volume 2, United States Department Of Agriculture -- Forest Service, United States Department Of The Interior -- Bureau Of Land Management

Environmental Assessments (CO)

This appendix documents BLM and Forest Service activities to involve and consult with other government agencies and the public in the preparation of the Final EIS for the potential leasing of the Iron Point and Elk Creek Coal lease tracts, as well as the issuance of a coal exploration license for an area within and surrounding the Iron Point Coal lease Tract.

Final Envrionmental Impact Statement: Iron Point Exploration License -- Iron Point Coal Lease Tract -- Elk Creek Coal Lease Tract, Volume 1, United States Department Of Agriculture -- Forest Service, United States Departement Of The Interior -- Bureau Of Land Management

Environmental Assessments (CO)

The Final Environmental Impact Statement (EIS) describes the physical, biological, social, and economic resources that would be potentially affected by leasing of the Iron Point and Elk Creek Coal Lease tracts as well as issuing an exploration license for an area within and surrounding the Iron Point Coal Lease Tract. The federal decisions to be made involve the approval or disapproval of coal leasing (the Iron Point and Elk Creek tracts) and of an exploration license. Some of the key issues for these proposed actions include: the potential effects of transporting over 19 million tons of coal per year from …

Measurement Of Microcarrier Weighted Floc Using The Environmental Electron Microscope, Viriya Vithayaveroj

Theses

Utilizing the concept of coagulation in conjunction with the sediment enhancement by microcarrier, the microcarrier process has been demonstrated in a laboratory investigation as an effective and economic operation in removing colloidal particles in an aquatic system. The microcarrier, an inert aluminum silicate particulate (Ottawa Sand) of 53 to 75 micrometers in diameter was used in this study. The interaction between the flocs and the microcarriers plays an important role in the mixing process. The principal objective of this study is to examine the structural interaction between the flocs and the microcarrier.

The study was designed into two stages, the …

Intelligent Process For Uasb Reactors, Sita Mohan

Theses

The Upflow Anaerobic Sludge Blanket (UASB) reactor is widely used for the anaerobic treatment of concentrated municipal / industrial wastewaters and sludges. Ability to handle high organic loading rates and cost effectiveness are often the most cited merits of the UASB process. Numerous mathematical models have been developed to describe the process and mechanistic phenomena in these systems. However, evidence in the literature of these models having been applied, either as control or diagnostic tools is limited. The use of intelligent process control mechanisms can greatly ease problems associated with operating these reactor systems.

The objective of this study is …

Determination Of Semivariogram Models To Krige Hourly And Daily Solar Irradiance In Western Nebraska*, G.G. Merino, D. Jones, David Stooksbury, Kenneth Hubbard

Department of Agricultural and Biological Systems Engineering: Faculty Publications

In this paper, linear and spherical semivariogram models were determined for use in kriging hourly and daily solar irradiation for every season of the year. The data used to generate the models were from 18 weather stations in western Nebraska. The models generated were tested using cross validation. The performance of the spherical and linear semivariogram models were compared with each other and also with the semivariogram models based on the best fit to the sample semivariogram of a particular day or hour. There were no significant differences in the performance of the three models. This result and the comparable …

Field Evaluation Of Ultrasound Enhancement Of Permeable Treatment Walls, Aamod Sudhakar Sonawane

Retrospective Theses and Dissertations

The objective of this research was to demonstrate the application of ultrasound to field sites having problems with precipitation build up and corrosion. PTW s are passive reactive walls containing zero-valent iron metal for in-situ remediation of contaminated groundwater. However, loss of reactivity over time due to build up of corrosion and other precipitates on the iron surface is a major concern. Ultrasound energy has been established as an effective tool for revitalizing iron surface. This research applied ultrasound energy to a zero-valent iron wall constructed below the ground surface to remove precipitates and iron corrosion, increasing iron reactivity. Two …