Quality of water in mines in the Western Middle Coal Field, Anthracite Region, east-central Pennsylvania

The quality of mine water in the 75 sq-mi Western Middle anthracite field, Pennsylvania was determined by sampling discharges and boreholes at 60 abandoned and flooded mines during 1975-78. The Vulcan-Buck Mountain mine, east-northeast of Mahanoy City, contains an estimated 6,100 acre-ft of water with a specific conductance of 380 to 460 micromhos and a pH of 4.4 to 4.6 units. Twenty-two mines are in a 15-sq mi area between Mahanoy City and Girardville, all of which closed prior to 1958. Seven of these mines in the Mahanoy Basin may contain 30,000 acre-ft of water. Specific conductance ranges from 630 micromhos in the Tunnel mine to 1,800 micromhos in the Gilberton mine. Fifteen of these mines are in the Shenandoah complex; specific conductance ranges from 240 to 310 micromhos in mines in the eastern end of the complex to 2,400 micromhos in the western end. The specific conductance of water in 25 mines in the Mount Carmel-Shamokin area ranges from 460 to 980 micromhos. The North Franklin mine near Trevorton contains about 4,900 acre-ft of water with a specific conductance of about 1,100 micromhos. (USGS)