Northeastern Section - 54th Annual Meeting - 2019

Paper No. 9-5
Presentation Time: 8:00 AM-12:00 PM

CHARACTERIZING AND MONITORING A HIGHLY PRODUCTIVE AQUIFER IN A TEACHING WELL FIELD ON THE CENTRAL CONNECTICUT STATE UNIVERSITY’S MAIN CAMPUS


ABBOTT, Henry W., EVANS, Mark A. and OYEWUMI, Oluyinka, Department of Geological Sciences, Central Connecticut State University, 1615 Stanley Street, New Britain, CT 06050

The CCSU teaching well field used for this study is located near the Geological Sciences Department in Copernicus Hall on the university’s main campus in New Britain, CT. The well field has a central well drilled to a depth of 25 feet below the surface with a 4 inch diameter casing, surrounded by 5 other wells drilled to a depth of 20 feet with a 2 inch diameter casing. The fully developed wells produce 2 to 3 gallons of water per minute, and are often used for teaching hydrogeology and environmental related classes. This study focuses on a detailed characterization of the aquifer’s properties as well as an assessment of changes in water chemistry and usability over time. To address this, we examined borehole logs to determine the aquifer thickness and borehole soil samples in order to determine the aquifer material and chemistry.

Stratigraphic analysis from borehole samples show a disturbed overburden soil layer containing mudstone and sandstone fragments, underlain by sandy to gravelly sediment, indicating unconfined aquifer materials. Geochemical analysis of the aquifer material provides information about its chemical nature and water chemistry, which is sampled on a weekly basis. Water chemistry data varies with application of road salt during snowstorm events, with concentrations of chloride (393.795 mg/L), nitrate (6.526 mg/L), and sulfate (25.04 mg/L) observed after the first snow storm of the season. Water level fluctuation in the wells, measured using HOBO data logger pressure transducers, correlate with precipitation events with little to no delayed response, indicating a high infiltration rate. After each recharge event, water levels show a consistent decline curve. Daily fluctuations of rising and falling water depth depict influences of earth tides in the aquifer.

Data monitoring will continue indefinitely to provide a long-term record. These data are continuous, and will be used to provide a detailed evaluation of the influence of human activities and aquifer material on the quality of water from the monitoring wells over time, as well as documenting a background data set for use in teaching and professional development.