Scarlatos, Panagiotis (Pete) D.

A complete understanding of nitrate partitioning between water and sediments is absolutely necessary to quantify eutrophication and other harmful effects of nitrate addition to a lake. The bottom sediments can act both as source and sink for nitrates. Turbulent conditions induced by wind forces cause sediments to suspend in the water column. During suspension sediments adsorb/release nitrates and other contaminants into the ambient water. This study investigated the effects of temperature, sediment and nitrate concentration on the exchange and partitioning of nitrates between water and sediments. The Langmuir adsorption model was used to quantify the adsorption/desorption processes. A decrease in the value of partition coefficient with increase in sediment concentration was observed. The laboratory experiments revealed that an increase in temperature of the water column favored the adsorption of nitrates by the bottom sediments. The nitrate diffusion coefficients were estimated by utilizing Fick's second law of diffusion. Sediment concentration profiles were strongly dependant on the oscillating-grid induced turbulence effects.

The specific effects of sediment resuspension on the rate and amount of phosphorus diffusion by commercially available kaolinite and bentonite soils were examined in a laboratory setting by amending the soils with phosphorus fertilizer (46% P2O5), reacting them in a plexiglass container (by removing a partition) and allowing the soils to mix with the overlying water column as they spread along the container bottom. The concentration of total phosphorus was measured at 1, 3, 6, 12, 24 and 36 hours after reaction occurred. A computer program was written to calculate the diffusion coefficients (D) for the different soil and fertilizer treatments. Correcting the D values for adsorption resulted in effective diffusion coefficients (De) values, averaged across all retardation factors, of 0.010; 0.0017 and 0.0124 cm^2/day for the 13,944; 9,295 and 4,648 mu g/1 phosphorus fertilizer kaolinite treatments and 0.0002; 0.0006 and 0.0013 cm^2/day for the 13,654; 9,103 and 4,552 mu g/1 phosphorus fertilizer bentonite treatments. The diffusion coefficients for the kaolinite soil treatments were consistently greater than those for the bentonite treatments.

This study pertaining to the settling of fine particles is developed using various models and formulas. The model considers two layers, i.e, the suspension zone dominated by perikinetic flocculation and the settling zone governed by gravitational force. In the suspension zone, floc formation of fine particles is simulated by the maximum chain model in which floc parameters and fractal dimension are compared with existing data. In addition, fractal dimension is compared with that of the hierarchical model. The main assumption of the model is that any floc having sixteen particles outweighs Brownian force, and thus the floc starts falling down into the settling zone. The flocs moving from the suspension zone are considered as nonspherical particles in the settling zone. The study uses a dimensionless settling velocity, omega*, for estimation of the sedimentation of flocs. Settling causes aggregation of the depositing flocs. The form of these aggregates is analyzed by the fractal relationship P ~ L delta.

In this thesis, a two-dimensional in the vertical plane numerical model has been developed for simulation of the free surface and density interface profiles due to a wind shear stress applied on a stratified water body, such as lake or reservoir. The results agreed qualitatively and quantitatively with our experimental results, as well as with the work of other researchers. A computer algorithm is established that can be used to estimate the shear stress along the interface and the velocity field throughout the water body. The model can be applied for prediction of wind-induced mixing processes in elongated lakes or reservoirs.

Due to the fact that most of closed-end canals are protected from high energy inputs, these canals tend to act as sediment traps. Accumulation of deposited material creates navigational and flood problems. Shoaling in closed-end canals is caused mostly by fine sediments. The behavior of fine sediments can be quantitatively described by means of a mass balance equation. More specifically, the advection-dispersion equation including proper sink/source terms can be used. The sink/source terms represent the processes of deposition and erosion respectively. The purpose of this thesis is to develop analytical solutions of the unsteady advection-dispersion equation as applied to free surface closed-end canals. Solutions are obtained under various initial and boundary conditions, by using the finite transformation analysis. The simulation results are validated against laboratory data.

Available air quality data has been analyzed using the Industrial Source Complex Dispersion Model (ISC3). The FORTRAN program Mobile 5a was utilized to obtain the emission factors. Concerning the toxic volatile organic compounds, the simulations indicate that benzene exceeded the previous permissible air quality standard. Toluene, ethylbenzene and xylene values remained within allowable concentration levels. Long-term annual benzene emissions from stationary sources exceeded the former reference concentration of 0.12 mug/m 3 about five times per year, whereas the data for 8 and 24 hours were relatively low. Simulation results for the mobile sources demonstrated that the emission factor is a highly sensitive parameter. Possible realistic scenarios at Port Everglades were obtained through varying benzene concentrations. The results are plotted as concentration contours, in order to visualize areas of suspected health risk associated to air pollution. Compared to the Reference Concentration for Chronic Inhalation Exposure, EPA, the modeled results appear significantly less.

Since the industrial revolution, industrial operations have been accompanied with a problem: production of industrial waste, which may be toxic, ignitable, corrosive or reactive. If improperly managed this waste can pose dangerous health and environmental consequences. This study defines the meaning of pollution prevention and outlines its major categories. Three different industries: wood furniture, marina and auto repair industries where chosen to emphasize pollution prevention practices throughout their operations.

The purpose of this thesis was to study the reliability and the accuracy of GPS positioning in Palm Beach and Broward counties. By studying the predictions of DOP values using Pathfinder Office and performing some statistical analysis on theoretical GPS data using the software SAS 8.0, the conclusion was made that PDOP values not only depend on the number of available satellites, but also on their relative positions. By field testing, and comparing the recorded data with the theoretical GPS data, it was seen that non-DGPS could be rather accurate. Furthermore, it can be justified for a GPS unit to eliminate the Z coordinate measurement since vertical position errors are larger than horizontal errors, which may lead to improved accuracy. On the other hand, some 'visibility problems' were encountered while testing the GPS units under driving conditions. Different ways to compensate for this disadvantage were studied. In the end, the different features of the GPS unit were discussed and a way to improve the system was also proposed.

The purpose of this study was to define the best Geographic Information System (G.I.S.) Software to manage the Storm Water Drainage Facilities for the Utilities Department of the Village of Tequesta, Florida. GeoMedia Professional was chosen, for its convenient user interface and its compatibility with other G.I.S. software such as ArcView or ARC/INFO. The GIS system displays the information in a map with different layers showing features such as drains or sewers. Subsystems were used to define the Levels of Standards (LOS) for the drainage system of the village. The data was collected from different sources such as Palm Beach County, or the property appraisers. The features are linked to databases, where the user can interface with the system and analyze the storm water network of the village. In the end, an interactive map was created with all the data, which provided a sufficient management tool for the Utilities Department.

Drainage waters leaving the Everglades Agricultural Area (EAA) have been implicated as having adverse effects on the receiving Water Conservation Areas (WCAs) and Everglades National Park (ENP). The objectives were to quantify and describe the rainfall and drainage events, characterize their effects on the water table system, and determine any relationships between the open channel drainage system and the field water tables on farms in the EAA. Water table rise in the soil profile from rainfall averaged a ratio of 10.6:1. Traditional expectations of field drainage behavior to channel gradients were not apparent. Field observation well drainage rates showed no direct relationships to distances across the farm or to the main station pumping rate. Due to the similar field water table responses under varying drainage scenarios, the organic soil, open channels, and the underlying geology were determined to function as an integrated system with respect to the movement of water.