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CA?d.hS Colorado, ]nc. Lontprtont Distel Operations Page 4 1l.'Ihe expansion areas are located in the i4fUD area. The post-mining uses include wildli~:e habitat and recreation. These uses are compatible with MUD goals and the limiting site factors. The final reclamation plan has been developed in conjunction with Longmont Parks :tnd Recreation to ensure compatibtlity of the post-minittc; land-use with the long term Itlanning goals of the azea. in response to urban growth in the area, the southern sections of the Peschel and Bigelav properties may potentially be developed as residential areas by the landowners after the completion of reclamation 12. the majority of the site is located within the 100-yr flood plain of St. Vrain Creek. The azea ie designated as Zcne A corresponding to Floodprone 7,or~e FP-1, base flood elevations itnd e~her flood hazard fataors undefined. However, mining activities in the expansion azea. aze not anticipated to have adverse impacts on local flood Hazard potential. Mining activities nre not expected to impact flood levels in the teach of the Saint Vrain Creek above the mining area. The open pit will be located within the 100.year t7o~~d plain. The post-mining lake; will increase loca3 flood storage capacity and reduce downsu•eam flood hazards. Oily small temporary topsoil and overburden stockpiles will be constructed around the periphery of the pi[ neaz Saint Vrain Creek. These stockpiles will be used to reclaim the open pit slopes. Reclamation of the pit slopes will be progressive and the temporary stockpiles will be removed when mining in each azea is ectnpleted, A permanent overburden stockpile will be developed in'~he southern portion of the Peschel property, approximately 2,000 feet south of Sain[ Vrain Creek, at the sout;tem limit cf the FEMA designated ] 00-yeaz flood plain (as shown on !lie FEMA Flood Insurance Rate Map Pastel 85Ui. It is anticipated that the area will be raised ;rpproximately 3 feet above current ground level. Because the permanent overburden stockFile is located near the limit of the flo~~d plain and outside the portion of the floodway that vzill carry high velocity flood !lows and debris, the stockpile is not expected to affect flood lo~e]s. There is a slight potential for starmding floodwaters to extend to the stockpile area; however, the stockpile will not be located in an area that will zxperience high velocity flood flows. As such, the permanent sta<;kpiie is not expected to impact the 100.yeaz flood level or present a flood hazazd. Ii required by W old Cottniy, a Flood Hazard Development Petmit will be obtained before: miring activities commence on the Peschel propem. \To other permanent structures will be creatzd in flood-prone azees in the proposed expansion arezs. The proposed expansion azeas do not lie in airport overlay or geologic hazard overlay districts. 13. Mine production will be increased from the cturent rate of 660,000 tonsryear to 300,000 tonsiyear. No change in the type of processing is proposal as part of this amendment. Tlie water supply plan during operations is being undated to czflzct the change in production rate and will he submitted to the State Engincers Office ~0.SRK0~C0MM0N`,Gxnd ~ inject\SQOPUSR APP~'~b~ Re9ui~emer ~e.doc