Knowledge Bank

Mountaintop removal mining involves excavating coal seams and depositing the spoil in valleys, often burying headwater streams. To explore the potential for restoring these headwater streams, a reach at Guy Cove, Kentucky, was restored on top of valley fill and monitored for discharge and basic water quality parameters. The restored stream loses water to the underlying fill over much of the year and sometimes vanishes before the end of the reach. In this study, we measured infiltration rates along the streambed using heat as a natural tracer in order to characterize locations of stream loss. Measurements were taken in mid-summer and late fall at eight locations representative of riffles, runs, and pools. The stream lost water to the underlying fill at most locations during both seasons, but losses were greater during the drier fall season. Rates of infiltration or exfiltration varied strongly along this reach and showed no clear relationship with morphology. The degree of compaction and the permeability of the streambed were not measured but may control infiltration rates. If so, streambed permeability should be viewed as a critical design element in future restoration efforts.