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West Elk Mine • 4. In the unlikely event that cracks do develop within the internal portions of the panels, there are various "healing" mechanisms which will act to fill in the crack within a few months. 5. Although surface cracks located over the pillars are less likely to "heal" themselves, they will fill in over time via "sealing" mechanisms, principally in the form of sediment inflows. 6. Most spring flows which infiltrate into surface cracks will re-emerge downgradient; consequently, the water will not be "lost" to the basin, which is important from a water rights standpoint. In short, it is very unlikely that the rechazge source for any given alluviallcolluvial spring or spring itself will encounter a surface crack. If this does happen, however, the ameliorating factors listed above will apply. Redrnrk , rinvc -From the information available, roughly one third of the springs in the permit area can be considered bedrock springs. All of the springs associated with formations are located well above the projected E-Seam fractured zone; consequently, these springs will not be measurably effected by fractures extending up from the mine workings. As noted above, if the relevant formations fall within the caved zone or the lower portion of the fractured zone, the springs maybe lost and the rechazge water may enter the mine workings. Springs associated with the upper portion of the fractured zone may be either lost into the mine workings or they may relocate to a lower • elevation. Although highly unlikely, consider an example in which 50 percent of the springs in the Apache Rocks and Box Canyon permit revision areas are in the caved and fractured zone. hi this very conservative scenario, the spring recharge water would drain into the mine workings. The implications of this scenario are not significant. The maximum number of springs that would be lost under this scenario within the Apache Rocks permit revision azea is 7 and in the Box Canyon permit revision azea the number is 2. 2. The combined dischazge of the relevant springs is, conservatively, 50 gpm. This represents less than 10 percent of the total spring dischazges ui the current permit and Box Canyon permit revision azeas, 3. The source water for these springs would be dischazged into the mine workings. Losses within the mine workings are estimated to be less than 5 percent. The remaining 95 percent of the inflow water would therefore be collected, treated and dischazged to the Dry Fork or the North Fork. Bedrock springs could potentially be impacted by surface cracks, but the logic presented in the previous section for colluviaUalluvial springs applies to bedrock springs also. Simply stated, there • is no significant risk to bedrock springs from surface cracks. 2.05-166 November 2004 PR! 1