The Nation - News from Jan. 2, 1989

Rain at a monitoring station in central Pennsylvania registered the highest acid content of 131 sites in 46 states, contributing to the state’s No. 1 ranking in acidic rainfall for 1987, an environmental group said. Federal monitoring data revealed that the most acid rain was recorded at the Leading Ridge in Huntingdon County, said the Natural Resources Defense Council, a Washington-based nonprofit group that has lobbied for sharp reductions in pollutants that cause acid rain, such as sulfur dioxide and nitrogen oxides. Rain there had an average pH of 4.08, which is 33 times more acidic than unpolluted rain, the council said recently. The pH scale measures acidity, with 7 being neutral. The lower the number, the more acidic the rain. Unpolluted rain is slightly acidic. Pollutants from coal-fired power plants, factories and cars are thought to undergo changes in the atmosphere and fall to Earth as acid rain.