Abstract

This dissertation reports on research related to groundwater and contaminant transport to the Volusia Blue Spring (VBS), an Outstanding Florida Water Body located in Volusia County (Florida). The integration of springshed water quality and contaminant fate and transport (CFT) modeling played key roles in the evaluation of anthropogenic recharge impacts on VBS. To study anthropogenic recharge into the karst limestone aquifer, wastewater effluent, golf course ponds, septic tanks, groundwater monitoring wells, and VBS discharge were sampled for boron, nitrate-nitrogen, nitrate-oxygen and their isotopes spatially throughout the VBS springshed. Data related to natural water features, rainfall, land use, water use, treated wastewater discharge, and septic tank effluent flows was used as inputs to the three-dimensional CFT model developed from an integration of MODFLOW-2000 and MT3DMS. The model was calibrated and validated from field observed water levels and water quality taken throughout the springshed. The purpose of this model is to understand groundwater and spring water quality throughout the VBS springshed. Water quality and model results indicate that water from the surficial aquifer in surrounding urban areas contributed to the flow and water quality at the spring's boil. Protection scenarios that included wetland treatment systems and the conversion of targeted septic systems to sewer were simulated to estimate future reductions of anthropogenic nutrients transported to the Spring. Of the scenarios evaluated in this study, targeted septic system removal results in the greatest benefit with a 36% nitrate decrease in a forty-year projection of spring discharge water quality. Results from this combined water quality and model development approach is expected to contribute an understanding of anthropogenic impacts from the urbanized developments overlying and surrounding the karst VBS aquifer.

Graduation Date

2016

Semester

Summer

Advisor

Duranceau, Steven

Degree

Doctor of Philosophy (Ph.D.)

College

College of Engineering and Computer Science

Department

Civil, Environmental and Construction Engineering

Degree Program

Environmental Engineering

Format

application/pdf

Identifier

CFE0006701

URL

http://purl.fcla.edu/fcla/etd/CFE0006701

Language

English

Release Date

February 2017

Length of Campus-only Access

None

Access Status

Doctoral Dissertation (Open Access)

Share

COinS