Paper No. 31-2
Presentation Time: 8:00 AM-12:00 PM
ASSIGNING AGE PARAMETERS OF THE BERRY COLLEGE GROUNDWATER TABLE
Determining the recharge rates of the local groundwater table is essential in understanding the quality of water in an unconfined aquifer. Located in Mount Berry, Georgia (34.2751N, 85.1833W) is the world’s largest college campus, Berry College situated upon a karst topography comprised mainly of the Floyd Shale and Conasauga Shale geologic units. Historically, this landscape has been plagued with sinkhole formation and has resulted in a fragmented geologic substrate. It has been heavily documented that human land usage through agricultural practices or industrial pollution has been directly correlated with the quality in a surficial aquifer. These solutions travel through the vadose zone at different rates dependent on factors such as permeability and precipitation to the groundwater table. While on the Berry College campus there are no groundwater wells used for human consumption, it is still important to be aware how human activity affects the groundwater quality. Several chemical compounds in the atmosphere including tritium (3H) and more commonly chlorofluorocarbons (CFCs) dissolve in precipitation and can be found in the groundwater with recharge rates of 50 years . This study utilizes a approach by measuring CFC-113 concentrations to determine the relative age of the groundwater table. Additionally, pesticide concentrations will be compared to provide a qualitative analysis of relative groundwater age. Five test wells have an average casing depth of 150 ft. and an average static water level of 35 ft. below the ground surface. Through the use of a Solnist pressurized discrete interval bailer, samples were collected at a depth of 100 ft in each test well. High-performance liquid chromatography of each water sample and chemical analysis dating techniques that were then averaged among samples allowed for a relative age of 20 years within the groundwater table. This study will provide a useful understanding of the time and age within the localized aquifer and how land management practices could influence groundwater quality.