REVISITING SCARLIFT 15: GEOCHEMICAL ANALYSIS OF AN ACID MINE DRAINAGE REMEDIATION SITE NEAR RANSHAW, PA

Pennsylvania has a long history of coal mining. In regions of past mining, poor environmental practices have produced disastrous acid mine drainage (AMD) issues. Though mining has been greatly reduced and new mines adhere to stricter environmental guidelines, the coal regions of Pennsylvania have inherited AMD-ridden “legacy mines” that closed before environmental regulation came into effect. The burden of restoring these legacy mining operations now falls to taxpayers through programs like Operation Scarlift. The Scarlift-15 site near Ranshaw, Pennsylvania is one such site. Scarlift-15 consists of a series of ponds meant to raise the alkalinity and reduce levels of dissolved metals in mine drainage from the abandoned Excelsior-Corbin colliery. It was completed in 2006 and began treatment that same year. This study was undertaken to evaluate the Scarlift-15 treatment site, now fifteen years old, to determine whether it continues to fulfill its purpose of AMD remediation. During this study, in situ sampling was conducted for pH, temperature, dissolved oxygen, and conductivity. In the lab, the water samples were analyzed for acidity, alkalinity, turbidity and filtered versus nonfiltered concentrations of Al, As, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn.In the treatment system, pH generally increased as water flowed through the system, ranging from about 3.3 to 7.1. Alkalinity tended to increase as water moved through the vertical flow ponds, but it was low in overflow water. Turbidity and dissolved oxygen were generally low in Scarlfit-15 and was higher in Shamokin Creek. Conductivity was generally higher in the treatment system than Shamokin Creek. The treatment system greatly reduced aluminum and iron. Not all the metals in the treatment system dissolved at the same rate, and there was a variation within metals between filtered and nonfiltered samples. Aluminum, iron, and manganese were the most detected metals in the Scarlift-15 treatment system. However, manganese does not change significantly through the treatment system, signaling that it is not as effectively removed as the other metals. Overall, it seems that the Scarlift-15 treatment system is continuously doing its purpose of adding alkalinity and removing aluminum and iron in the water from acid mine drainage.