The 32-square-mile central part of the Pine Bush was studied to determine the availability of ground water in the surficial sand and to assess the quality of the water, especially with respect to phosphorous, nitrogen, and chloride. The surficial sand is from 5 to 150 feet thick and has a hydraulic conductivity of 68 feet per day. Recharge is solely by precipitation. Depth to water is about 10 feet but ranges from 5 to 20 feet locally. The water table and total precipitation have been declining since 1979. A computer model was used to simulate drawdowns that would be produced by pumping the aquifer at various rates. Results indicate that a single well could yield from 150 to 600 gallons per minute, depending on hydraulic conductivity, which was simulated at 25, 50, and 100 feet per day, allowing a maximum drawdown of 80% of total saturated thickness. Ground water contained low phosphorous (maximum of 0.04 mg). (USGS)