Acid mine drainage where the ore is a sulfide mineral or is associated with pyrite. In these cases the predominant metal ion may not be iron but rather zinc, copper, or nickel. The most commonly mined ore of copper, chalcopyrite, is itself a copper-iron-sulfide and occurs with a range of other sulfides. Thus, copper mines are often major culprits of acid mine drainage. At some mines, acidic drainage is detected within 2–5 years after mining begins, whereas at other mines, it is not detected for several decades. In addition, acidic drainage may be generated for decades or centuries after it is first detected.
Ore Run Formation. The upper reaches of the stream flow over rock of the Burgoon Sandstone formation. Rock outcroppings are present in the watershed. The entire length of the stream flows over soil of the Deep-Wellsboro-Oquaga soil association, except for the headwaters, which are on soil of the Oquaga and another, minor soil association. Most of these soils are highly acidic. There is a bed of iron ore on Ore Run. The watershed of Ore Run has an area of . Ore Run is difficult to access. The Ore Run Falls are a cascade and slide waterfall on Ore Run. They are