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The effects of mineral reactions on trace metal characteristics of groundwater in desert basins of southern ArizonaMarozas, Dianne Catherine January 1987 (has links)
The geochemistry, of groundwater collected from deep wells in the western section of the lower Santa Cruz basin of southeastern Arizona, was studied in order to determine the extent to which geochemica] analysis can be used to assess fluid flow and major and trace element migration patterns along hydrologic flowpaths in desert basins. Interaction between groundwater and enclosing sediments, and mixing between chemically distinct basin groundwater is found to exert a significant control on the chemical patterns that have evolved in the system. Activity-activity diagrams of the Na-Si-O-H system show that groundwater throughout the basin clusters near the three phase boundary between fluid, kaolinite, and montmorillonite and trends along the boundary to higher log (aNa⁺/aH⁺) values. A reaction model generated with computer program PHREEQE, that combines silicate weathering, kaolinite-Na-beidellite equilibrium, calcite equilibrium, and solution mixing, can simulate trends in groundwater composition along flowpaths in the basin. Trace metals introduced into the basin by the weathering of a buried porphyry copper deposit become spatially separated upon migration. Metal concentrations are found to be correlated to major cation concentrations. Cu is associated with high Na concentrations and a high ratio of Carbonate:Ca, whereas Zn is associated with high Ca concentration and a low ratio of Carbonate:Ca. Behavior of Cu and Zn during low-temperature transport can be controlled by the effects of mineral alteration on groundwater composition. Computer analysis of early basin diagenesis shows that changes in major solute composition that accompany weathering, constrained by equilibrium with clays and calcite, can produce the metal segregation pattern observed in the basin. Because the aquifer is strongly influenced by silicate and carbonate mineral equilibrium, the introduction of Central Arizona Project recharge, which is not in equilibrium with alluvial minerals, into the basin, requires a response by mineral reactions that attempt to restore the system to a state of equilibrium with kaolinite, montmorillonite, and calcite. A reaction model is developed to predict the consequent effects of outside recharge on groundwater quality.
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The hydrogeochemistry of recharge processes and implications for water management in the southwestern United StatesVandemoer, Catherine,1955- January 1988 (has links)
A geochemical approach to the evaluation of the chemistry of natural recharge processes in the Tucson basin was used to identify the major minerals controlling the evolution of ground water chemistry and to assess the viability of recharging imported Central Arizona Project water supplies. Well cuttings analyses and water quality samples from over 65 wells in the basin were used as input to the geochemical computer model PATH4 (Helgeson, 1970) and the sequence of aqueous species and mineral production in a recharge reference volume examined. The study reveals that natural processes in the basin lead to the increase in dissolved solids content in ground water over time and the production of secondary minerals such as calcite, calcium montmorillonite, kaolinite and poorly crystallized alumino-silicate phases. Secondary minerals grow into aquifer pore spaces and may, over time, be responsible for the reduction in aquifer porosity and the specific capacity of wells. The recharge of imported Central Arizona Project water will lead to an increase in the dissolved solids content of ground water and may, in certain areas of the basin, lead to the enhanced production of secondary minerals. The use of CAP water as a recharge source must be guided by the geochemical factors which influence the nature and scope of reactions between CAP water and the Tucson aquifer matrix. The study demonstrates the need for and identifies water quality and aquifer matrix criteria for the assessment of sources of recharge water and recharge facility sites. The use of geochemistry as a tool for quantitatively assessing ground water quality is demonstrated.
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Avaliação da qualidade da água subterrânea de poços tubulares outorgados no município de Campo Grande - MS /Cardoso, Juarez Marques January 2019 (has links)
Orientador: Jefferson Nascimento de Oliveira / Resumo: A grande proporção da exploração das águas subterrâneas no Brasil e no mundo se deve às inúmeras vantagens como a qualidade da água, os custos de exploração relativamente baixos e o simplificado tratamento da água para consumo. A importância de se estudar estes recursos hídricos se coloca pela necessidade de investigar os processos em que se dá a exploração da água, desde a autorização da captação do recurso, a gerência de potenciais contaminantes, até a sua qualificação como boa ou imprópria para consumo pela população. Deste modo, o presente trabalho avaliou a qualidade de água subterrânea outorgada do município de Campo Grande, Mato Grosso do Sul e utilizou como fonte dos dados o Sistema IMASUL de Registros e Informações Estratégicas do Meio Ambiente – SIRIEMA, on-line, disponível no site do Instituto de Meio Ambiente de Mato Grosso do Sul (IMASUL), pelo qual se realiza todo o procedimento de solicitação e análise de outorga e que autorizou a publicação dos dados dessa pesquisa seguindo os princípios de acesso às informação sobre Recursos Hídricos , conforme instrumento estabelecido pela Lei Federal 9433 de 1997 e Lei Estadual 2406 de 2002, sob o cuidado ético do sigilo dos nomes das pessoas físicas e/ou jurídicas. O trabalho foi realizado com base nas análises físico-química e microbiológicas de poços outorgados, inseridas no SIRIEMA como parte da documentação obrigatória para solicitação de outorga e dados qualitativos de monitoramento de tais fontes de captação. Foram e... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The large proportion of groundwater exploitation in Brazil and in the world is linked to numerous advantages such as water quality, relatively inexpensive operating costs and simplified treatment of water for human consumption. The study and investigation of water resources is necessary to know the processes of exploration of water, from the authorization of the capture of the resource, the management of potential contaminants, until the qualification as own or improper for consumption by the population. Thus, the present study evaluated the groundwater quality granted in the municipality of Campo Grande, Mato Grosso do Sul and used the IMASUL System of Registries and Strategic Environmental Information - SIRIEMA, available on the website of the Institute of Environment of Mato Grosso do Sul (IMASUL), where all the procedure of request and analysis of granting takes place and that authorized the publication of the data of this research following the principles of access to information on Water Resources, according to instrument established by Federal Law number 9433 of 1997 - Brazil and State Law number 2406 of 2002 - Mato Grosso do Sul, under the ethical care of the secrecy of individuals and / or legal entities. The work was carried out based on the physical-chemical and microbiological tests of wells granted, inserted in SIRIEMA as part of the mandatory documentation for requesting data and qualitative data of monitoring of such sources of abstraction. We found parameters ... (Complete abstract click electronic access below) / Mestre
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Application of multivariate statistical method to characterize the groundwater quality of a contaminated siteChiou, Hsien-wei 07 February 2010 (has links)
In this study, a chlorinated-solvent contaminated groundwater site was used as the study site. Multivariate statistical analysis explains the huge and complicated current situation of the original data efficiently, concisely, and explicitly; it simplifies the original data into representative factors, or bases on the similarity between data to cluster and identify clustering outcome. The statistical software SPSS 12.0 was used to perform the multivariate statistical analysis to evaluate groundwater quality characteristics of this site.
Results show that 20 analytical items of groundwater quality of the study site are simplified into seven major representative factors through factor analysis, including ¡§background¡¨, ¡§salt residual¡¨, ¡§hardness¡¨, ¡§ethylene chloride¡¨, ¡§alkalinity¡¨, ¡§organic pollutant¡¨, and ¡§chloroform¡¨. The factor score diagram was drawn according to the score of monitoring well on each factor and 89.6% of the variance could be obtained. This study used cluster analysis to cluster in two phrases, the groundwater quality monitoring wells were classified into seven clusters according to the similarity of monitored data nature and the differences between clusters. The groundwater quality characteristics and pollutant distributions of each cluster out this site were evaluated. The clustering result indicates that for the sixth cluster (where monitoring well SW-6 was the representative well), the average concentrations of chlorides such as 1,1-dichloroethylene, 1,1-dichloroethane, and cis-1,2-dichloroethylene were the highest among the clusters, indicating those the groundwater of nearby area might be polluted by chlorinated organic compounds. In addition, to evaluate whether the clustering of cluster analysis were appropriate or not, discriminant analysis is used to evaluate clustering accuracy, in which seven Fisher discriminant coefficient formulas that were exclusively suitable for this location were established. Then, the observed values were substituted to Fisher discriminant coefficient formula. Result shows that the monitoring well¡¦s clusters obtained from discriminant analysis were totally identical with the result of actual cluster analysis; the accuracy were 100%. After performing cross-validation analysis, the result shows that the accuracy were 80%, indicating the use of discriminant analysis (with forecasting function) to verify the clustering result of the cluster analysis was highly accurate.
After analyzing the pollution condition of this site using time trend and space distribution, it were determined to conclude that trichloroethylene and 1,1-dichloroethylene were the major concerning pollutants; the pollutants appeared to be spreading on a large scale, so it was difficult to use the existing data to evaluate the pollution source. After assessing environmental medium characteristics and pollutant distribution of the site, this study suggests that the use of insitu bioremediation, which is cost-effective, can be applied as a remedial mothod.
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Impact of mining operations on the groundwater quality within Vantech mine area in Mpumalanga province, South Africa.Singo, Mangaga. January 2008 (has links)
Thesis (MTech. degree in Environmental management.)-Tshwane University of Technology, 2008. / Aims to generate information on the quality of water from boreholes and the Steelpoort river in order to ascertain the level of pollution within the vicinity of Vantech mine. The information is envisaged to help a better water management within the area. The following objectives were pursued: to measure water quality parameters ; to investigate the extent of the pollution plume movement ; to study the composition and geological factors in the area in relation to mobility of groundwater and to determine the impacts of Geo hydrological characteristics.
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Ποιότητα των υπόγειων νερών των γεωλογικών σχηματισμών του νομού ΗλείαςΔημητριάδου, Σταυρούλα 03 April 2015 (has links)
Η παρούσα διπλωματική ερευνητική εργασία μελετά τους παράγοντες που διαμορφώνουν την ποιότητα των υπόγειων νερών του νομού Ηλείας. Στην εργασία παρουσιάζονται τα αποτελέσματα που προέκυψαν από τις εργαστηριακές αναλύσεις 99 δειγμάτων νερού, που περιλαμβάνουν σημεία υδροληψίας από το μεγαλύτερο μέρος του νομού. Τα δείγματα αυτά συγκεντρώθηκαν στο πλαίσιο της τεχνικής έκθεσης με τίτλο «Έλεγχος της ποιότητας των υπόγειων νερών ύδρευσης των πλέον επιδεκτικών σε ρυπάνσεις πυρόπληκτων περιοχών του νομού Ηλείας» που ανέθεσε η Νομαρχία Ηλείας το 2008 στο εργαστήριο Υδρογεωλογίας, με επικεφαλής τον καθηγητή κ. Νικόλαο Λαμπράκη.
Το γεωλογικό υπόβαθρο του νομού Ηλείας διαμορφώνεται από την Ιόνια ζώνη, τη ζώνη Ωλονού - Πίνδου, τη ζώνη Γαβρόβου Τρίπολης, Τριτογενείς γεωλογικούς σχηματισμούς και Τεταρτογενείς αποθέσεις. Στους Νεογενείς σχηματισμούς που εντοπίζονται και καλύπτουν το μεγαλύτερο μέρος του νομού, αναπτύσσονται υδροφόρα στρώματα που ταξινομούνται βάσει του προτύπου IAH/UNESKO του 1995. Οι σημαντικότεροι υδροφόροι ορίζοντες αναπτύσσονται στους σχηματισμούς Βούναργου και Χελιδονούς - Ολυμπίας, Καλαθά και στις ποτάμιες αναβαθμίδες Αλφειού και Ζαχάρως. Η περιοχή εμφανίζει έντονη τεκτονική με σημαντικότερες ρηξιγενείς ζώνες, τη ζώνη του Βούναργου, του Πράσινου, του Αλφειού και του Πελόπιου - Ολυμπίας.
Με την επεξεργασία των φυσικοχημικών παραμέτρων των δειγμάτων στο πρόγραμμα Phreeqc 3.0 καταλήξαμε σε τρεις υδροχημικούς τύπους για τα νερά της Ηλείας. Επικρατεί ο τύπος Ca-HCO3 που φανερώνει φρέσκα νερά και κατανέμεται σχεδόν ομοιόμορφα στην περιοχή μελέτης. Ο τύπος Ca-HCO3-SO4 οφείλεται κυρίως στη διάλυση της γύψου των Νεογενών, στο κεντρικό τμήμα του νομού. Στον τύπο Ca-Na-HCO3 η ύπαρξη Νατρίου αποδίδεται σε διαδικασίες ιοανταλλαγής, παρουσία εβαποριτών της Ιόνιας ζώνης ή γειτνίαση με τη θάλασσα. Κανένα από τα παραπάνω στοιχεία δεν ξεπερνά ωστόσο τα όρια ποσιμότητας (Oδηγία 98/83/EC).
Για τη στατιστική επεξεργασία των δεδομένων χρησιμοποιήθηκε R-τύπου παραγοντική ανάλυση, με τη βοήθεια του προγράμματος SPSS 17.0. Για τη χωρική κατανομή των παραγοντικών τιμών που προέκυψαν χρησιμοποιήθηκε η μέθοδος Ordinary kriging στο ArcMap 9.3. Επιλέχτηκε ένα τετραπλό παραγοντικό μοντέλο που εκφράζει το 75% της αρχικής πληροφορίας. Ο πρώτος παράγοντας συνδέει τη θερμοκρασία του υπόγειου νερού με το Λίθιο και το Βόριο και κατανέμεται στην ερύτερη περιοχή του Κατάκολου. Πρόκειται για μια γνωστή σχέση που ευνοείται από θερμομεταλλική κυκλοφορία υδάτων, έντονη τεκτονική, μεγάλους χρόνους παραμονής και βαθείς υδροφόρους. Ο δεύτερος παράγοντας συσχετίζει τον Σίδηρο και το Μαγγάνιο με αναγωγικά περιβάλλοντα στους υδροφόρους της περιοχής Αμαλιάδας - Πηνειού. Ο τρίτος παράγοντας απηχεί την αυξημένη συγκέντρωση Χρωμίου, Ουρανίου και Αρσενικού σε αναγωγικές συνθήκες, στο κεντρικό τμήμα του νομού. Τον τέταρτο παράγοντα αποτελεί το δυναμικό οξειδοαναγωγής που εμφανίζει αρνητικές τιμές στα αναγωγικά περιβάλλοντα και συνδυάζεται με τα αποτελέσματα του δεύτερου και του τρίτου παράγοντα. / The present master’s thesis examines and interprets the factors that influence the groundwater quality in Elia Prefecture, Peloponnese. Moreover it elaborates the results of the laboratory analysis of 99 water samples that have been collected in the frame of a technical assessment carried out in 2008 by the Hydrogeology Laboratory and its head professor Nikolaos Lamprakis. The assessment entitled “Drinking groundwater quality assessment of the most susceptible of contamination regions in Elia Perfecture that have been affected by fire” was assigned to the Hydrogeology Laboratory by the Regional Council of Elia.
The geological background of Elia Prefecture is formed by the Ionian zone, the Olonos - Pindos zone and the Tripolis zone, as well as Tertiary formations and Quaternary alluvial. Inside the Neogene formations several water-bodies have been developed. These are classified according to the IAH/UNESCO standard of 1995. The most productive aquifers are those of Vounargon, Helidon - Olympia, Kalathas, Alfeios and Zacharo fluvial conglomerates. Intense tectonic activity occurs in the study area. The most important fault zones are those of Vounargon, Prasinon, Alfeios and Pelopion - Olympia.
The physical and chemical parameters of the samples have been processed by Phreeqc 3.0 resulting in three hydrochemical types of groundwater in Elia. The prevailing type is Ca-HCO3 that indicates fresh water, which is evenly distributed over the study area. The dilution of the gypsum of the Neogene formations causes the Ca-HCO3-SO4 type to occur. The Potassium concentration in the Ca-Na-HCO3 type is attributed to ion-exchange processes, to the presence of evaporates or to the proximity of the aquifers to seawater. Nevertheless, the aforementioned concentrations were below the permissible limits (Directive 98/83/EC).
The method used for the statistical analysis was R-type factor analysis that has been performed in SPSS 17.0. To acquire the spatial distribution maps of each factor Ordinary kriging interpolation method was used, in ArcMap 9.3. The statistical analysis resulted in a four-factor model that represents the 75% of the initial-values information. The first factor associates the groundwater-temperature to the presence of Lithium and Boron. It is the dominant factor over the area around Katakolo. It indicates a well-known relation which is a function of thermometallic water circulation, tectonic structures, long residence time and deep aquifers. The second factor expresses the relation of Iron and Manganese to reducing conditions in the aquifers of Amaliada and Pineia. Redox potential is the third factor. Its negative values point out reducing environments that are confirmed by the examination of the distribution maps of the second and third factor.
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As condições socioeconômicas, o saneamento básico e a qualidade da água subterrânea em Anastácio (MS): aspectos relacionados à percepção ambientalAyach, Lucy Ribeiro [UNESP] 10 January 2011 (has links) (PDF)
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ayach_lr_dr_rcla.pdf: 1499974 bytes, checksum: 8e9818fcc007c2b1d00068fb6b168056 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O estudo proposto avalia a influência da percepção ambiental na qualidade ambiental e de vida dos moradores urbanos, em relação às diferentes realidades ambientais, vivenciadas na cidade de Anastácio, Estado de Mato Grosso do Sul (MS), Brasil. Foram considerados os aspectos socioeconômicos, de saneamento básico, de qualidade das águas subterrâneas e a identificação das implicações da percepção ambiental dos moradores quanto ao aspecto sanitário domiciliar, nas condições gerais de infraestrutura urbana, ambiental e de saúde, visando subsidiar ações, de modo efetivo, para a melhoria da qualidade de vida dos seus moradores. A linha da pesquisa participante foi adotada como proposta metodológica para alcance dos objetivos, utilizando-se abordagens quanti-qualitativas, com a interpretação das diferentes variáveis a partir da visão sistêmica. Os resultados confirmam a influência da percepção ambiental dos moradores nas diversas variáveis que comprometem a qualidade ambiental e de vida dos habitantes da cidade, e a carência de medidas de planejamento ambiental-urbano / The proposed study evaluates the influence of environmental perception of the urban population in their environmental and life quality related to distinct environmental realities experienced in the city of Anastácio, in Mato Grosso do Sul (MS), Brazil. Under consideration in this study were the socioeconomic aspects of basic sanitation, the underground water quality and the identification of the implications from urban inhabitants’ environmental perception considering basic sanitation in their urban housing conditions and the general conditions of their urban, environmental and health infrastructure; intending to subsidize actions in an efficient manner to improve their life quality. The participative research method was adopted as the methodological proposal to reach research goals using an approach which is both quantitative and qualitative, with the interpretation of different variables from a systemic viewpoint. Results confirm the influence of the environmental perception from the inhabitants in the variables which endogener their environmental and life quality and also the lack of actions in the urban environmental planning level
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Caracterização do aqüífero associado ao Complexo Alcalino Carbonatítico do Barreiro, oeste de Minas Gerais / Characterization of the aquifer related to the Barreiro Alkaline Carbonatitic Complex, West of Minas Gerais.Raposo, Daniel Bernardes, 1980- 12 December 2011 (has links)
Orientador: Sueli Yoshinaga Pereira / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-19T20:22:44Z (GMT). No. of bitstreams: 1
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Previous issue date: 2011 / Resumo: O aquífero associado ao Complexo Alcalino Carbonatítico do Barreiro (CACB) foi estudado através da análise de testemunhos de furos de sondagem rotativa em seções geológicas verticais. O modelo conceitual interpretado é de um aquífero principal, granular e semi-confinado e dois outros, ambos fissurais e confinados, um deles relacionado ao topo da rocha sã e o outro a sistemas de falhas ou fraturas profundas, esse último se manifesta em nascentes mesotermais e fortemente mineralizadas. Sistemas de falhas descritas na bibliografia e observadas em afloramentos produziram um sistema anisotrópico. Testes de bombeamento de longa duração indicam que os parâmetros hidrodinâmicos variam de um local para outro, o que mostra que o principal aquífero é heterogêneo. Os diferentes litotipos e a grande variação na espessura do manto de intemperismo interferem diretamente nas características hidrodinâmicas. A condutividade hidráulica pode variar de 0,17 a 1,0 m/dia, e é maior nas regiões com presença de silexitos. Também foi observado que os poços com as maiores vazões, geramente superiores a 150 m3/h, perfuraram zonas com silexitos...Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital / Abstract: The aquifer related to the Barreiro's Alkaline-Carbonatitic Complex (CACB) was studied by analyses of sample cores and vertical geological sections. The conceptual model was interpreted as a main aquifer, granular and semi-confined and two others subordinated aquifers, fissural and confined, one of them is related to the top of fresh rock, and the other one is related to the deep fault zones that contains waters strongly mineralized and can be observed in mesotermal springs. Fault zones are described in the literature and are also observed in outcrops. Those faults produced an anisotropy system over the saprolites. Pumping tests have shown that the hydrodynamic parameters can change from one place to another. This fact indicates that the main aquifer is heterogenous and has a strong interference of the lithotypes. The range of hydraulic conductivity is from 0.17 to 1.0 m/day, with the highest values in regions with silexites. It has also been observed that the wells with the highest pumping rates, generally higher than 150 m3/h, are also located over silexites zones...Note: The complete abstract is available with the full electronic document / Mestrado / Mestre em Geociências
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Characterisation of groundwater in mainly old and closed landfill sitesGajree, Meenu January 1999 (has links)
A study is made of the use of chemical analysis of groundwater samples to assess groundwater quality. Samples from forty-seven boreholes within and around ten landfill sites in the London Borough of Hounslow were analysed. Most of the landfill sites studied were filled prior to the implementation of the Control of Pollution Act 1974 and were not designed with environmental protection in mind. Boreholes were tested for methane, carbon dioxide and groundwater samples were analysed for electrical conductivity (EC), ammonium nitrogen (NI14-N), COD, TOC, Cl-, NO3, SO42-, Na+, K+, Ca2+, Ni2+, Cu2+, Pb2+, oxidation - reduction - potential (ORP) and pH. The first ten of these analytical parameters were considered for groundwater quality assessment and the most important selected for more detailed study namely CH4, C02, EC, NH4-N, COD and TOC. Pollution ratings are allocated on the basis of single pollutant analytical data and averaged for each of the bore hole samples. Goodness of fit values between the single analyte values and the average data were calculated and no set of single analyte data was found to provide good groundwater quality assessment. A series of formulae combining the six analyte parameters was considered and the data evaluated by goodness of fit calculations to provide an effective means of assessing groundwater quality. The ratings obtained from the best formula are compared with historical broad band classification of landfill sites and show how sites must be assessed on the basis of samples taken from within the site and not around the perimeter. The production of acetic acid in the acetogenic phase of landfill reactions will increase the leachability and mobility of many metal pollutants and particularly of lead. Studies on the leachability of lead in acetic acid media show how lead solubility is increased in acetic acid media by the formation of triacetatolead(II) species, Pb(CH3CO2)3-.
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Urban stormwater injection via dry wells in Tucson, Arizona, and its effect on ground-water qualityOlson, Kevin Laverne, 1954-, Olson, Kevin Laverne, 1954- January 1987 (has links)
My deepest respect and appreciation are extended to Dr. L. Gray Wilson for providing the opportunity to conduct this research, for his advice and assistance during the course of the research, and for his review of and suggestions for improving this manuscript. I would also like to thank Michael Osborn for his assistance. This research was funded by the City of Tucson. The assistance and direction provided by Mt. Bruce Johnson and Mt. Joe Babcock at Tucson Water are gratefully acknowledged. My thanks are also extended to Dr. Daniel D. Evans, Dr. L.G. Wilson, and Dr. Stanley N. Davis for serving on my thesis committee. Bruce Smith's assistance is gratefully acknowledged. Bruce spent two long days with 110-degree temperatures In a parking lot describing the lithology of sediment samples collected during the drilling phase of this research. He also determined the moisture content and particle size distribution on samples collected from the borehole. The assistance of Ralph Marra and Steve Brooks is also gratefully acknowledged. Ralph waded through city and county bureaucracies to determine zoning at each dry-well site. Steve assisted with collecting dry-well settling chamber sediment samples.
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