The ice application of agricultural limestone (220 mesh, 5 tons/ha) to White Deer Lake in February 1985 followed four seasons of baseline data collection. Immediate chemical changes in the lake occurred for total alkalinity, specific conductance, calcium, Secchi depth, magnesium, and silica as the limestone continued to dissolve for nearly seven months. In October 1985 White Deer Lake began to exhibit clear patterns of re-acidification such as declining total alkalinity, and changes in specific conductance, calcium, and magnesium following the dilution of the treated waters after Hurricane Gloria. Reacidification continued through the summer of 1986. Monitoring continues at White Deer Lake.