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Quantifying Groundwater Discharge Using Thermal Imagery And Conventional Groundwater Exploration Techniques For Estimating The Nitrogen Loading To A Meso-Scale Inland Estuary, Robert M. Roseen
Doctoral Dissertations
This dissertation presents the results of a study to evaluate groundwater inflow and nutrient loadings to the Great Bay Estuary, New Hampshire. The evaluation of inflow was accomplished independently by two methods: one, used thermal imagery, and the other, piezometric mapping. The thermal imagery method assessed groundwater that was observed to discharge within the intertidal zone of an inland estuary. The groundwater piezometric mapping method used the monitoring wells around the bay to create an overall piezometric map of the near-bay area. Groundwater discharge was evaluated with respect to flow, concentration, and ultimately nitrogen loading to coastal waters. The results …
Oxygen And Nitrate Enhanced In Situ Bioremediation Of An Oil -Contaminated Salt Marsh, Fabio A. Roldan-Garcia
Oxygen And Nitrate Enhanced In Situ Bioremediation Of An Oil -Contaminated Salt Marsh, Fabio A. Roldan-Garcia
Doctoral Dissertations
Salt marshes are among the most ecologically-sensitive areas to oil spills and remediation activities. Contaminated marshes may take years or decades to recover. Bioremediation is the process of enhancing naturally-occurring biodegradation by supplying limiting nutrients and terminal electron acceptors (TEAS). During this study, two TEAS (O2 and NO3 -) were evaluated for their ability to enhance natural in situ biodegradation of total petroleum hydrocarbons (TPH) in an oil-contaminated marsh. EPA (9071A) and ASTM (D5831) methods were evaluated for screening TPH in the contaminated marsh sediments. The ASTM Method was selected to evaluate TPH levels in candidate sites at the Fore …
Testing For The Significance Of Induced Highway Travel Demand In Metropolitan Areas, Lawrence Craig Barr
Testing For The Significance Of Induced Highway Travel Demand In Metropolitan Areas, Lawrence Craig Barr
Doctoral Dissertations
The theory of induced growth in vehicle travel hypothesizes that highway improvements which add capacity to a specific corridor or regional transportation network will attract increased levels of vehicle traffic. This relationship of highway capacity to travel demand is an important consideration when evaluating how effective highway expansion alternatives will be in solving transportation problems. Two different but complementary empirical studies were conducted to quantify the effect of highway system improvements on travel behavior. In the first study, I apply ordinary least squares regression models to estimate travel demand elasticities with respect to travel time using travel survey data from …