A Transient Green’s Function Flow and Particle Tracking Model to Quantify a Coupled River-Aquifer System: Application to the Assessment of Possible Groundwater Contamination from a Floridan Industrial River

Abstract

The Fenholloway river is a small industrial river flowing through Taylor county, north Florida, into the Gulf of Mexico (Fig. 1). About 15 miles upstream of the river-mouth, southeast of the town of Perry, a cellulose paper kraft mill (for legal reasons, named henceforth the ‘B’ -plant) has been operating since 1954 and discharges approximately 50 million gallons/day (= 77.5 ft³/s) of wastewater into the river. Since the average river flow rate measured at a stream gauge station closely downstream from the ‘B’-plant’s effluent point is about 87.1 ft³/s, most of the river flow is sustained by the wastewater outflow of the ‘B’ -plant. This is particularly the case during the semi-annual dry seasons, which in Florida are usually from April-June and October-December. The amount of input water for the paper mill’s manufacturing process is about equal to the volume of wastewater effluent and consists of groundwater pumped by 8 production wells that are located upstream of the plant and which extend down into the high-yielding formations of the (mostly confined) Suwannee limestone aquifer. This aquifer forms the upper part of the vast Floridan carbonate aquifer which supplies most of the drinking water in the State of Florida.