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on site) the applicant will provide design documents showing the design, size and <br />location of such ditches. The ditches will be identified on the mining and <br />reclamation plan maps. The applicant will submit additional financial warranty if <br />required. <br />Exhibit "E ", Reclamation Plan 6.4.5 <br />1) compacted clay liner or slurry wall <br />The reservoirs are planned to be lined using a slurry wall. Neither the pit slopes <br />nor the pit floor will be lined with compacted clay. The bedrock on site underlying <br />the sand and gravel is the Pierre Shale. This geologic unit has very low <br />permeability and as such is highly suitable for reservoir construction. <br />2) topsoil salvage and stockpiles <br />Exhibit F: Reclamation Plan Map has been revised to show the location of the <br />existing topsoil stockpiles. These stockpiles contain a minimum of 257,000 cubic <br />yards of topsoil. No part of these stockpiles will be sold off site and the <br />stockpiled material will be used on site for reclamation purposes. <br />Exhibit "G ", Water Information 6.4.7 <br />1) Excelsior ditch <br />The Excelsior ditch is approximately 3,300 feet north of the north permit <br />boundary, it is unlined. The sand and gravel aquifer at the mine site and <br />extending north to the area beneath the Excelsior ditch has very high <br />permeability. Pumping water (i.e., dewatering) in high permeability aquifers <br />creates a cone of depression that will not even come close to the Excelsior ditch. <br />The ditch most likely leaks, but the amount of the leakage is trivial compared to <br />the amount of water in the aquifer as a whole. <br />Lafarge and Stonewall Springs Quarry, LLC have been dewatering the same <br />aquifer at a mine immediately west of St. Barbara for years with no known <br />impacts to the Excelsior ditch. <br />2) Chico Creek <br />Chico Creek is approximately 4,400 feet east of the easternmost permit <br />boundary. It is an ephemeral drainage. The same discussion above concerning <br />the Excelsior ditch applies to Chico Creek. The cone of depression caused by <br />pumping at the St. Barbara mine would not come anywhere near Chico Creek. <br />