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Mitigation of Impacts to the HvdrolcMic Balance of the Permit and Adjacent Areas Sun Coal Company, in the permit application package, predicted that the Meadows No. 1 Mine would have a negligible impact on the hydrologic balance of the permit and adjacent areas. The prediction discussed potential impacts to surface water and ground water. All of the disturbed azea drains, either directly or via its tributaries, to the Yampa River. Sun Coal Company has monitored surface water discharges from ponds over the liability period, the results of which indicate dischazge from the mine does not exceed established effluent limits. The sedimentation ponds discharge each Spring, in response to snowmelt. The history of compliant dischazges from the ponds indicate that pollution of surface water is not occurring, and is not expected to occur in the future. Monitoring of water in the Yampa River through February 1986 indicated there was no apparent effect from the mine on surface water quality or quantity. The Division approved a technical revision (TR 04) in February 1986, to allow Sun Coal Company to reduce surface water monitoring to pond dischazges only. At that time, the Division found there had been no impact from the mine on the Yampa River. Mining at the Meadows No. 1 Mine did not disrupt any local aquifers. No ground water of regional significance has been detected at the mine. The nearest regional aquifer is the overlying Trout Creek Sandstone. The area which has been mined lies stratigraphically below the Trout Creek Sandstone aquifer, and the Trout Creek Sandstone does not ocwr within the mining area. The operation did not affect any of the neazest major regional bedrock aquifer, therefore the probability that the mine caused degradation of water quality in the aquifer is nil. The Pinnacle coal seam was mined at the outcrop, in the recharge zone. No water was encountered in the coal seam mined (Pinnacle) or in any of the overburden strata which were disturbed during mining. There are no adjudicated wells in the Pinnacle coal seam aquifer in the vicinity of the mine. The Division, in its 1988 "Proposed Decision and Findings of Compliance" document for the first permit renewal, predicted that a spoils aquifer could potentially develop in the area of the backfilled pit. To date, the absence of spoils springs indicate that a spoils aquifer did not develop. The document also noted that prior to mining, the Pinnacle coal seam received no groundwater recharge due to an impervious shale above the seam. Breaking, removal, and mixing of the shale during mining and reclamation processes resulted in the shale layer no longer restricting recharge of the coal seam. However, standard percolation tests demonstrated that infiltration and percolation rates through the bacldill are so low that rechazge is not expected. Accordingly, the potential for groundwater degradation was considered remote. There is no evidence that the quality or quantity of ground water in the Pinnacle coal seam has been affected by mining operations at the Meadows No. 1 Mine. Meadows No. 1 Mine 8 Phase nI Bond Release