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<br />Page 3 <br />Item #6: Hydrologic Balance <br /> <br />Water well Permit #38262 (issued to Fred Craig) is on the Timko property. Afield visit <br />to the SW, NW Section 32 revealed a water well on the Timko property. A revised <br />Exhibit G-l is attached showing the approximate location of this well. <br />The revised Exhibit G-1 also shows the location of the groundwater monitoring well <br />installed on the Acord property by Owens Brothers Concrete Co. The well was installed <br />on September 13, 1996 to a total depth of 25 ft. It is a 2" diameter monitoring well <br />completed in the alluvial aquifer. The screened portion of the well extends from 3 ft. <br />below ground surface to the total depth of the well. Groundwater was encountered at 6 <br />ft. below ground surface at the time of drilling. <br />Two additional groundwater monitoring wells will be installed on the property prior to <br />mine disturbance. One well will be installed in the vicinity of the Timko well and the other <br />well will be installed in the southern portion of the property. A water level monitoring <br />plan including at least five quarters of data will be submitted to the Division prior to mine <br />start up. The monitoring plan will include a definition of negative impact and a mitigation <br />plan. We request that these provisions be made conditions of permit approval. <br />Item #7: Direction of Groundwater Flow <br />There are no on-site monitoring wells on the property. The expected direction of <br />groundwater flow (i.e. towards St. Vrain Creek) was assumed based on topography, <br />experience with similar alluvial environments and conversations with gravel mining <br />companies in the vicinity. The installation of three monitoring wells on the property will <br />allow an accurate determination of the direction of groundwater flow on a seasonal basis. <br />Item #8: Dewatering Impacts on Wetlands <br />The mining and reclamation operations were designed to avoid excavating or filling in <br />designated wetlands. The U. S. Army Corps of Engineers does not regulate dewatering <br />adjacent to a wetland even if the dewatering negatively impacts the wetland. Our initial <br />response to this item is that this issue is not regulated by the Federal government under the <br />Clean Water Act. <br />The Division is correct in the assumption that dewatering adjacent to the wetlands may <br />temporarily lower the groundwater that is the source of the wetland vegetation. As <br />mining is completed in an area adjacent to wetlands, the groundwater will recover to its <br />original level and, we believe, continue to support wetland vegetation. There are currently <br />no plans for mitigation of potential wetland impacts except that creation of ponds and <br />shorelines during reclamation will create more aquatic habitat and greatly expand the <br />