||Acid-Base Status of Pennsylvania Streams: Results from the National Stream Survey.
Eshelman, K. N. ;
Kaufmann, P. R. ;
Herlihy, A. T. ;
||Corvallis Environmental Research Lab., OR. ;Virginia Univ., Charlottesville.
Water pollution ;
Mine waters ;
Stream flow ;
Forest land ;
Mine acid drainage
||Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy.
The National Stream Survey (NSS) conducted by the Environmental Protection Agency in the spring of 1986 sampled 82 stream reaches within the state of Pennsylvania, representing a target population of 9900 stream reaches that are potentially sensitive to acidification. After excluding streams acidified by acid mine drainage, an estimated 9% of the reaches were chronically acidic during spring baseflow at the upstream end while less than 1% of the stream reaches were acidic at their downstream end. Comparable percentages of streams with an acid neutralizing capacity (ANC) between 0 and 50 (mu)eq/L were also identified, with the majority of these streams found in the Appalachian Plateau. Almost all of the chronically acidic streams in the state are small (<20km(2)), upland headwater streams draining watersheds that are more than 95% forested. Population estimates of the percentages of streams with an ANC less than 200 (mu)eq/L agree favorably with estimates by the Pennsylvania Fish Commission for managed and unmanaged stream sections in the state.