Characterization of Natural Wetland Soils Receiving Acid Mine Drainage

Abstract

A proposed section of Appalachian Corridor H will pass through an area of the Beaver Creek watershed in Tucker County, WV previously mined for the acid-producing Upper Freeport coal. Presently, partially-reclaimed spoils from past mining activities are generating acid mine drainage. Wetlands adjacent to the spoils are supporting vegetative communities and they appear to be naturally treating the drainage. We characterized soils of the acid mine drainage- impacted wetlands and non-impacted wetlands to establish baseline soil status and to compare the acid mine drainage-impacted soils and non-impacted soils. We analyzed soil samples for pH, sulfate, acid volatile sulfides, chromium reducible sulfides, organic sulfur, total sulfur, total carbon, and total iron. Platinum redox electrodes were placed in some of the wetland soils to assess near surface redox chemistry. Wetlands receiving acid mine drainage generally contained higher levels of total sulfur, and the sulfur in these wetlands was more likely to be in the form of acid volatile sulfides, sulfate, and/or chromium reducible sulfides. Chromium reducible sulfides ranged from 0.0 to 103.4 umol g -1 and acid volatile sulfides ranged from 0.0 to 32.3 umol g -1 in all wetlands. The carbon content in wetlands receiving acid mine drainage was generally lower than the non-impacted wetlands and the iron content was generally higher in the acid mine drainage- impacted wetlands. Redox values indicated that conditions are present in impacted wetlands for iron and sulfur reduction to occur.