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Analysis Of Qa/Qc Protocols And Value Of Data To The Development Of Reference Criteria In The Georgia Ecoregions Project, Tracy Jo Ferring
Analysis Of Qa/Qc Protocols And Value Of Data To The Development Of Reference Criteria In The Georgia Ecoregions Project, Tracy Jo Ferring
Theses and Dissertations
The concept of Measurements Quality Objectives (MQOs), in bioassessment programs is a useful tool in evaluating the consistency of data and limiting variability and potential sources of measurement error. Typical evaluations of data repeatability and/or data quality center on the use of a series of calculations that quantify variability between measures. These calculations provided some indication of not only the quality of the data collected, but also acted as a measure of how representative the biological data were to each ecoregion. The evaluation of the Quality Control data for this project provides a framework for data users and water resource …
Paleoenvironmental Reconstruction Of The Late Cretaceous Eastern Gulf Coastal Plain In Georgia And Alabama, Tracy L. Hall
Paleoenvironmental Reconstruction Of The Late Cretaceous Eastern Gulf Coastal Plain In Georgia And Alabama, Tracy L. Hall
Theses and Dissertations
The present study reconstructs the regional paleoenvironment (particularly paleoclimate) of the Late Cretaceous Eastern Gulf Coastal Plain of Georgia and Alabama using paleobotanical, paleoecological and geochemical methods in order to evaluate the Late Cretaceous climate of the Southeastern United States, and to add to the body of paleoclimate data for that time. Paleobotanical analysis indicates a terrestrial mean annual temperature (MAT) of about 27°C during the Late Cretaceous, which is considerably warmer than modern terrestrial MAT. Stable oxygen isotope data from molluscan carbonate indicate mean sea surface temperature (SST) of 26.8 °C for the Santonian, 23.5°C for the early Campanian, …
Development Of Biological Reference Conditions Of Wadeable Streams In The Major Ecoregions And Subecoregions Of Georgia, Duncan L. Hughes
Development Of Biological Reference Conditions Of Wadeable Streams In The Major Ecoregions And Subecoregions Of Georgia, Duncan L. Hughes
Theses and Dissertations
One bioassessment tool available to resource managers to indicate NPS impairment of wadeable streams and rivers are multi-metric invertebrate indices. Such indices are assembled from metrics in broad categories that represent different aspects of community structure and function (e.g. richness, composition, tolerance/intolerance, feeding group, and habit). Indices must incorporate suites of metrics that are ecologically relevant, quantifiable, non-redundant, and that best individually discriminate between reference sites and impaired sites. More than 240 wadeable streams in Georgia were sampled during the September thru February index period using RBP protocols during three successive sample seasons (1999-2003). Ecoregional reference (minimally impaired) sites, as …
The Effects Of Nutrient Concentrations On Macroinvertebrate Distributions In Georgia, Paula Michele Pollock Brossett
The Effects Of Nutrient Concentrations On Macroinvertebrate Distributions In Georgia, Paula Michele Pollock Brossett
Theses and Dissertations
Nutrients are considered the second largest nonpoint source pollutant in Georgia's running water ecosystems. Nutrients can naturally occur in low amounts and are typically increased in streams as a result of industry, agriculture, silviculture, and urbanization. In large amounts, nutrients can cause many problems to occur in the stream ecosystem. Macroinvertebrates have been established as good indicators for determining the level of impairment of a stream; however, not much research has been done on how nutrients affect macroinvertebrates in a stream. Approximately 225 reference and impaired streams were sampled over a 3 - year field season, (index period from September …
Modeling Groundwater Flow And Contaminant Transporting Fractured Aquifers, Jason M. Bordas
Modeling Groundwater Flow And Contaminant Transporting Fractured Aquifers, Jason M. Bordas
Theses and Dissertations
The hybrid discrete fracture network/equivalent porous medium (DFN/EPM) model was selected for analysis and application to simulate a contaminated site in this study. The DFN/EPM was selected because it appeared to have the potential to aid decision making by remedial project managers at contaminated DoD fractured aquifer sites. This model can use data that are typically available at a site while incorporating the important processes relevant to describing contaminant transport in a fractured medium. The model was applied to simulate the operation of a pump-and-treat remedial action at a trichloroethene-contaminated fractured aquifer at Pease AFB. The model was able to …
Modeling Application Of Hydrogen Release Compound To Effect In Situ Bioremediation Of Chlorinated Solvent-Contaminated Groundwater, Ryan C. Wood
Theses and Dissertations
This study investigates how application of Hydrogen Release Compound (HRC) might be implemented to remediate a site contaminated with tetrachloroethene (PCE) or its daughter products, under varying site conditions. The 3-D reactive transport model RT3D was coupled with a dual-Monod biodegradation submodel to simulate the effect of the hydrogen generated by HRC on accelerating the biodegradation of dissolved chlorinated solvents. Varying site conditions and injection well configurations were investigated to determine the effect of these environmental and design conditions on overall treatment efficiency. The model was applied to data obtained at a chlorinated solvent contaminated site at Vandenberg AFB, where …
Evaluation Of Fuel Oxygenate Degradation In The Vadose Zone, David A. Torres
Evaluation Of Fuel Oxygenate Degradation In The Vadose Zone, David A. Torres
Theses and Dissertations
Groundwater contamination by petroleum products poses a potential human health and safety risk. Methyl tert-butyl ether (MTBE) was a commonly used fuel oxygenate that was added to gasoline to meet environmental regulations. The widespread use of MTBE resulted in significant contamination of drinking water supplies across the United States. This research evaluated the degradation characteristics of potential alternative fuel oxygenates in the vadose zone. One fuel oxygenate being considered as an alternative to MTBE is diisopropyl ether (DIPE). Specifically, this thesis sought to answer three research questions: what is the potential for DIPE degradation in soil without prior microbial augmentation, …
Validation Of An Innovative Groundwater Contaminant Flux Measurement Method, Seh J. Kim
Validation Of An Innovative Groundwater Contaminant Flux Measurement Method, Seh J. Kim
Theses and Dissertations
The ability to measure groundwater contaminant flux is increasingly being recognized as crucial in order to prioritize contaminated site cleanups, estimate the efficiency of remediation technologies, measure rates of natural attenuation, and apply proper source terms to model groundwater contaminant transport. An innovative mass flux measurement method using horizontal flow treatment wells (HFTWs) was developed recently to compensate for the disadvantages of other flux measurement methods that are being used. Flux measurement methods can be categorized as either point methods or integral methods. As the name suggests, point methods measure flux at a specific point or points in the subsurface. …
The Effect Of Sample Size On Rapid Bioassessment Scores And Management Efficiency, Uttam Kumar Rai
The Effect Of Sample Size On Rapid Bioassessment Scores And Management Efficiency, Uttam Kumar Rai
Theses and Dissertations
The rapid bioassessment method for stream bio monitoring generally uses a fixed count of 200 macro invertebrates as the standard subsample size. This number has been argued to be too small to provide accurate estimates on the richness of macro invertebrate communities and is believed to give misleading information pertaining to stream health. In this study, I used data collected from multiple habitats from 29 streams located in several subecoregions of Georgia to examine how the rapid bioassessment scores perform across subsample sizes of 100, 200, and 300 organisms. Subsample sizes of 100 and 200 organisms were found to underestimate …