Acid Rock Runoff Disrupts Pennsylvania Road Project

摘要

After a month, work is still halted on a section of Interstate 99 in Centre County, Pa., where water runoff from excavated acidic rock is threatening two fishing streams. In early March, the Pennsylvania Dept. of Environmental Protection and the Dept. of Transportation halted work on a half-mile stretch of the 28-mile-long reconstruction project. Up to 1 million tons of an acidic sandstone formation, excavated and moved to six dump sites to flatten the highway's path over the ridge, contains pyrite. When exposed to air and water, pyrite oxidizes and produces acidic discharges that can kill aquatic life. The stone also contains fish-killing aluminum.