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no water pollution is occumng, and there is no potential for future water pollution. Impacts to ground water and surface water aze described below. Ground Water Impacts: The Division conducted a detailed analysis of potential ground water impacts at the Cazbon Junction Mine in a review of the 2003 annual hydrology report. The results of the analysis are described in a memo to the annual hydrology report file dated June 11, 2004. Should ground water degradation occur, the following two aquifers are the most likely to be degraded by mining at Carbon Junction: the Animas River alluvium (one-half mile downslope from the mine) and the Pictured Cliffs Sandstone (subcrops beneath the mine pits). Alluvial aquifers: Animas River alluvial water can be expected to have not been degraded by mining because the less than 50-acre surface azea of spoil at the mine would not generate enough leachate to overcome the dilutional effect of native alluvial ground water. Bedrock aquifers: Downgradient monitoring well 95-1 is within the expected flowpath of any coal spoil leachate that would be generated in the Carbon Junction backfilled pits. This well has not shown evidence of leachate. Absence of leachate indicates the operation is in compliance with the Basic Standards for Ground Water (Colorado Water Quality Control Regulation 41.S.C.6). Cazbon Junction's approximate ] 00-acre surface disturbance probably is not enough to diminish recharge to bedrock aquifers. Surface Water Impacts: There aze no natural surface water features in the bond release area. Ditches route runoff to the sediment control ponds of the sand and gravel operation, and then is dischazged via CDPS outfalls at those ponds to the ephemeral stream channel in Carbon Junction Canyon. Oakridge has conducted long-term monitoring at the two outfalls. The ponds usually hold water only a few weeks each yeaz following springtime snow melt and lazge rainstorms. There have been no exceedances of dischazge limitations at either outfall for at least 5 yeazs. The dischazge limitations applicable to the outfalls were based on which chemical constituents were likely to be present in dischazge effluent, and did not include all of the constituents for which there are instream standards in the Animas River, downstream from Cazbon Junction Canyon. It is unlikely, however, that the influent would have contained these other constituents in significant amounts, therefore, it is reasonable to conclude that operations in the bond release azea are in compliance with the instream standazds. Impacts to Alluvial Valley Floors (AVFs): There are no alluvial valley floors within the influence of the Cazbon Junction Mine.