2003-03-31_REVISION - M1977344 (2)

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Exploration conducted by Holcim in the Bear Creek watershed has indicated that no groundwater table is present above the top of the Codell sandstone. Consistent with what has been observed to the west side of the north-south fault that divides the property (roughly parallel to the western boundary of the area to be mined in the lower Bear Creek watershed; see Figure C-2), discontinuous, perched, saturated zones are believed to exist in the overlying limestone and shale formations. The first unconfined aquifer in the lower Bear Creek area is located in the underlying Codell sandstone. This has been proven by Holcim's experience in the west side of Cuts 2 and 3, where mining has thus faz progressed to the top of the Translime layer of limestone: no saturated conditions have been observed. Holcim believes that once the Lower reach of the Bear Creek watershed is mined, backfilled, and reclaimed, the water that presently flows out of the limestone formation bedding planes/fractures will no longer do so, since the disturbed profile will disrupt the present subsurface flow system. To the extent that the current lower Bear Creek stream flow is the result of recharge due to irrigation of agricultural lands north of Highway SQ the disruption of the limestone bedding planes/fractures that currently feed lower Bear Creek will significantly reduce and likely eliminate the already low base flow in this portion of Bear Creek. The result will be a net increase of deeper infiltration to and saturation of the lower portions of any remaining unmined limestone and/or the underlying Codell sandstone in the lower Beaz Creek area. Eventually, equilibrium will be reached, with a net outflow into the Arkansas River alluvium and/or into the underlying sandstone aquifer. The quality of groundwater in the azea after mining is completed should be consistent with that of pre-mining conditions. Wildlife Resources Wildlife resources in the Holcim Portland Quarry area are limited by the generally moderate to low quality habitat on the site, and have been documented in the original permit amendment application. The most notable habitat in the area is located along the lower Bear Creek corridor, where surveys have indicated that, although potential habitat suitable for the Arkansas Darter (state threatened) and Southern Red Belly Dace (state endangered) exists, neither species is present. Habitat values decline rapidly with distance from the stream, and in the upland areas dry rangeland conditions exist in those areas not impacted by steep erosional slopes. As discussed with the Division of Wildlife and the Division of Minerals and Geology, it is unlikely that the pre-mining habitat of lower Bear Creek could be reestablished after mining, even if the stream channel was restored to its pre-mining alignment (horizontally and vertically). The disruption of the hydrologic system due to the mining process, as discussed above under Water Resources, will greatly reduce or eliminate the lateral flow and recharge to the stream of any water percolating through the bacl~lled landscape. Therefore, Holcim has applied for and received a 404 Permit from the Corps of Engineers to mitigate the loss of Bear Creek wetlands through the construction of replacement wetlands at the mouth of Hardscrabble Creek along the Arkansas River upstream of the plant site. Wetlands mitigation construction, restoration, and planting are scheduled to be completed by November 30, 2005. Beyond the establishment of the required wetlands acreage at the mouth of Hardscrabble Creek, Holcim will also enhance the lower 03S miles of the Hardscrabble stream corridor to provide many of the features necessary to create potential plains- native fish habitat. The great majority of the reclaimed acreage at the Holcim Portland quarry will remain as dry rangeland. The overall flatter slopes of the post-mining landscape, combined with an overall post- Exhibit E - revised.doc Page 3 of 5