Since November 1979, the Tar Creek watershed has received highly mineralized acid mine discharges from flooded underground lead-zinc mines of the Picher Field in Ottawa County, Oklahoma. Upon cessation of mining activities, drifts and shafts of the abandoned mine works began to flood. The acid water reacted with the surrounding rock causing many of the metals present to dissolve, resulting in high concentrations of zinc, lead and cadmium in the water. Discharge of these acid ground waters at the surface has resulted in degradation of Tar Creek and could eventually affect the Roubidoux aquifer which is the region's current water supply. The cost-effective remedial alternative selected for this site includes: diversion and diking at two major inflow areas and possibly a third if it becomes an inflow site, the plugging of 66 Roubidoux aquifer wells, and implementation of a monitoring plan. The capital cost for diversion at the three sites and well plugging is estimated to be $4,000,000. The annual O&M costs are $5,000 for monitoring.

"06/06/84." "PB85-214021." "EPA/ROD-R06-84-004." "Office of Emergency and Remedial Response."