TRACE ELEMENT PARTITIONING IN COAL MINE DRAINAGE AND IMPACTED WATERS, HARRISON COUNTY, WEST VIRGINIA

Lamberts Run is a tributary of the West Fork River and is impacted by drainage from abandoned coal mines within its watershed. In this study, we examined the distribution of iron, manganese and trace elements in discharge downstream of one abandoned mine portal and after its entry into Lamberts Run. Construction of a wetland and passive treatment system is slated to begin along this discharge in summer 2006. Dissolved iron and manganese, which were present in the mine discharge at concentrations of 7 and 6 mg/L, respectively, demonstrated sequential precipitation over the approximately 200-m distance between the mine portal and creek. Significant loss of manganese from the water and net accumulation in the sediments was not observed until 100 m downstream of the portal. Trace elements Ba, Co, Cr, Ni and Zn were detected in water, sediment and black coatings on stream cobbles in Lamberts Run. The trace elements are progressively enriched, relative to iron and manganese, respectively through those media. The coatings contained over 55,000 mg/kg manganese and high concentrations of the trace elements. Selenium was at or below the detection limit in water and sediments but substantially enriched in the black coatings (72 mg/kg). Diffusive equilibration in thin film (DET) and redox gel probes were used to measure sediment porewater concentrations at high resolution in the near-surface sediments.