||Oak Openings Community is a 4,587 acre County Renewal area situated on a surficial sand aquifer. Ground water samples were extracted from near the bottom of the aquifer through drive points at four sites. At five additional sites ground water samples were extracted through well screens installed across the water table. Surface water samples were collected from drainage ditches at eight sites. Samples were collected from these surface water and groundwater sites seven times between May 4, 1972, and March 9, 1973. Each sample was analyzed for calcium, magnesium, sodium, potassium, chloride, nitrate, bicarbonate, lead, zinc, cadmium, iron, specific conductance, pH, total dissolved solids, and hardness. All water was the calcium-bicarbonate type, and surface water was more highly mineralized than ground water. Mineral equilibria calculations using analyzed values of dissolved species suggest that both ground water and surface water are in near equilibrium with aquifer minerals except for sodium and chloride, which imply additional halite that is not known to be a natural aquifer mineral.