Hydrologic data are presented for area 5 of the Eastern Coal Province, the 7,384 square-mile Monongahela River basin in western Pennsylvania, western Maryland, and north-central West Virginia. One hundred thirty-four streams were sampled about three times during the 1979 and 1980 water years for specific conductance, pH, acidity, alkalinity dissolved and total iron, dissolved and total manganese, dissolved sulfate, and dissolved solids. Benthic invertebrate populations were determined and bottom material samples were analyzed for metals. Eleven streams had pH, acidity, alkalinity, total iron, total manganese, and dissolved-sulfate levels indicative of acid-mine drainage. These streams were most common in the Tygart Valley River basin, although indicators of acid-mine drainage were found throughout the Monongahela basin. No benthic invertebrates were found in 25 of 129 streams sampled. Such streams were most common in the Cheat and Tygart Valley River basins. Low flow, mean flow, peak flow, and flow duration data are presented for gaging stations in area 5. Techniques for estimating these data for ungaged sites are presented and referenced. The functions of, and access to, the National Water Data Exchange, WATSTORE, and indexes to water-data activities in coal provinces are presented. (USGS)
