Occurrence of beds of low hydraulic conductivity in surficial deposits of Florida

The disposal of municipal and industrial wastes on or at shallow depths below land surface can result in contamination of ground water--the source of drinking water for more than 90 percent of Florida 's residents. This threat to public health has resulted in new State groundwater regulations. Knowledge of the ability of surficial deposits to retard movement of contaminants is important to the implementation of these regulations. This map report shows areas where beds of at least 10 feet thickness with a hydraulic conductivity (saturation) of less than 0.1 foot per day occur within 50 feet below land surface, based mainly on interpretations of lithology. The map is intended as a guide for making preliminary assessments and should not be considered definitive of permeability beneath a specific site. Available determinations of hydraulic conductivities of surficial deposits in Florida are shown in table format. (USGS)