Scarlatos, Panagiotis (Pete) D.

The Village of Tequesta typifies an older storm water system. The infrastructure for the system has not kept up with development within the community. The design was for the conditions at the time of initial development. The levels of services provided are pertinent to establishing a direction and long term goals under current conditions. The existing seven and a half miles of conduit was modeled for a 25 year 24 hour storm. The rainfall amount simulated for the Tequesta area is 10.48 inches within a tidal area. The effects of the tide and the conditions of the conduit system lead to a realization that surface drainage is deeply affected by the tidal ranges associated with storm events.

The purpose of this study was to develop a user-friendly mathematical model for prediction of daily, ground level ozone concentration in Palm Beach County, Florida. The focus of this project was to investigate the correlation between hourly ozone concentrations and pre-existing pollutant levels and meteorological data. An artificial neural network model was applied, involving a backpropagation algorithm and the tangent sigmoid as the transfer function. Surface meteorological data and upper air data such as pressure, temperature, dew point temperature, wind speed and wind direction were included in the model, along with the ozone concentration in the hour previous to the forecast. Based on the model results, the 8-hour average ozone concentration is to be forecasted. This will assist state and local air pollution officials in providing the general public with early notice of an impending air quality problem.

The C-23, C-24, C-44, North St. Lucie, and Tidal St. Lucie drainage basins in southeastern Florida contribute major pollutant-laden discharges to the St. Lucie Estuary. One of the key goals of several of the Indian River Lagoon Restoration Feasibility Study (IRLRFS) project features is to reduce the timing and delivery of freshwater discharges to estuary receiving waters. The WPA option is the most widely accepted feature. This regional water quality improvement system has been mentioned as either the centerpiece, or major part, of the solution to the St. Lucie Estuary discharge problem. As a result, this research effort seeks to predict WPA water quality impacts to the St. Lucie Estuary. The goal is to utilize numerical water quality modeling techniques to arrive at changes in discharge loading quantities of selected parameters that may result from the operation of the WPA system per its preliminary design.

Disposal of construction and demolition (C&D) debris is a major problem. During recycling operations, the debris is passed over screens, generating what is called Recovered Screened Material (RSM). Previous analyses of RSM indicated high arsenic (As) levels. Thus, RSM is disposed in landfills in spite of the fact that natural soils may contain As levels higher than the proposed concentrations for soil clean-up goals. RSM samples were collected and analyzed from seven C&D debris recycling facilities and from other sites. The average arsenic content found in RSM ranged between residential and industrial clean-up goals. Chromium and lead levels in RSM were very low. The RSM quality depends mainly on the waste stream. Recycling procedures do not have any major effect on the RSM. Arsenic levels in natural soils showed a wide variability. Almost half of the soil samples had an arsenic level comparable to that found in RSM.

Sediment exchange characteristics of tidal inlets subjected to tidal excitations are investigated and the results compared to field data measured at Jupiter Inlet, Florida. A specially written computer program combines inlet/nearshore hydrodynamic expressions with bed-load and suspended load sediment transport relationships to examine the building mechanisms of the near-shore tidal ebb shoal. The ebb tidal flow is modeled as a turbulent, plane jet which includes lateral mixing and entrainment, bottom friction, and offshore bathymetric changes. Flood tidal flow is modeled as a potential flow sink with the water being drawn into the inlet from one or more dominant offshore areas depending on the offshore bottom slope. Sediment transport expressions are evaluated at various locations within the offshore flow field and the sediment deposition depth is calculated at that location over one tidal cycle. Model results are plotted and compared to field data for analysis.

The South Florida Water Management Model was developed to evaluate proposed alternatives for the south Florida regional hydrologic system. The degree of certainty of the computed system performance measures is required to correctly apply these measures for evaluation and selection of appropriate water resources policies and investments. Initially, a sensitivity matrix is defined which summarizes the model output sensitivity to incremental changes of key parameters. The method of singular value decomposition is applied to the sensitivity matrix to better understand relations between parameters and output variables. Finally, parameter uncertainty is compared to that of total predictive uncertainty of the system performance measures.

An artificial neural network is used to predict the stable geometry of alluvial rivers. This knowledge is useful for the design of new channels or modification of natural rivers. Given inputs of river discharge, slope and mean particle size, an artificial neural network is trained to predict the corresponding stable channel width and depth. The network is trained using data from several alluvial canals and rivers. Various factors including training set size and composition, number of hidden layer nodes, activation function type, and data scaling method are analyzed as variables affecting network performance. These factors are studied to determine impacts on network accuracy and generalizing ability.

Modem technology has led to a new generation of landfill liner systems that are
highly efficient at intercepting and removing leachate. Many of the modem liner systems
are so effective that little or no leakage occurs through the liner systems. What leakage
may occur is so minimal that, although it can be theoretically predicted, it cannot be
measured, i.e., the resulting groundwater concentrations are well beneath minimum
detection levels of available monitoring well technology. In addition to being highly
effective, some modem liner systems are constructed with two liners separated by a
drainage medium which detects and removes any leakage through the top liner.
These significant improvements in liner system technology have led many landfill
designers, operators, and regulators to question the necessity for current monitoring well
practices. Currently, landfills are required to have a large number of monitoring wells,
and the associated large installation, sampling, and testing costs are inevitably reflected
in higher tipping fees or higher taxes. In either case, the costs are borne by the public.
If the number and frequency of sampling of monitoring wells could be reduced,
significant cost savings could be realized, and the money saved could perhaps be better
spent elsewhere.
This thesis reports the results of research conducted at eleven landfills constructed
with modem landfill liner systems to determine the actual and probable efficacy of the
role o: monitoring wells, and conducts a cost-saving analysis to evaluate whether funds
would have been better spent elsewhere.

Phosphorus exchange between sediment-water system was observed under molecular diffusion and turbulent condition. Some experiments were focused on adsorption behavior under common environmental factors (e.g., temperature, salinity and pH). The sediment suspension was found to have a significant effect on phosphorus movement to the upper layer water. Higher temperature increased the release of phosphorus from kaolinite and lake sediments, and the effect was almost nil for bentonite. Temperature effect was pronounced on kaolinite where relatively higher release of phosphorus observed. Salinity effect on lake sediments was not significantly important for release or adsorption. Bentonite showed a release of phosphorus after addition of salts. Adsorption on kaolinite was found higher at pH 4.7-5.0. The study was also focused on the estimation of phosphorus partitioning due to molecular diffusion and turbulent mixing. The observed behavior of the phosphorus exchange under different conditions showed an agreement with the observations by the other investigators.