GEOCHEMICAL ANALYSIS OF GROUNDWATER DISCHARGE TO A TRIBUTARY OF YELLOW CREEK, O'NEIL WOODS, SUMMIT COUNTY, OHIO

The hydrology of an unnamed tributary to Yellow Creek in O'Neil Woods Metro Park, Summit County Ohio was investigated. Samples were collected from a wetland monitoring well, a spring, tributary waters upstream and downstream of the wetland, and Yellow Creek during fall 2005. The pH of the samples ranged from 6.61 to 7.54, with an average of 7.19. The total dissolved solids (TDS) of the samples ranged from 639 mg/L in Yellow Creek to 937 mg/L in the tributary upstream of the wetland. Four samples were classified on a piper diagram as calcium carbonate rich, one was classified as mixed cation and carbonate rich, and one was classified as calcium rich mixed anions. Groundwater samples showed low concentrations of sodium, with values under 12 mg/L, while Yellow Creek and the tributary upstream from the wetland contained over 80 mg/L. All samples were near saturation with respect to calcite, with saturation index (SI) ranging from -.78 to .476. The samples of groundwater (spring and monitoring well) were undersaturated with respect to calcite while all other samples were oversaturated. It is estimated that groundwater discharge from the wetlands accounts for 65 to 70 % of the water in the tributary based on mixing models that assume Na is behaving conservatively.