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<br />INSPECTION OF EXCESS SPOIL FILL RECEIVED <br />Second Quarter 2004 Certification <br />Fi11 Area No. 7 SEP 1.5 2004 <br />Date: June 12, 2004 <br />Givision of Minerals and Geology <br />GENERAL DESCRIPTION OR REFERENCE TO SITE PLAN: <br />The CTL Thompson report dated Apri127, 2001, "Stability Analysis and Geo-technical Recommendations <br />Lorencito Surface Mine Phase I" addresses the general requirements as also cited in Sections 4.09.1 to <br />4.09.2 of the Colorado Mined Land Reclamation Boazd for Coal Mining. <br />ACTIVITY DURING INSPECTION: <br />_Removal of Topsoil and Organic Matter <br />Placement of Under-drains <br />Installation of Surface Drainage System <br />Construction of Fill <br />_Placement of Topsoil <br />X Seeding <br />Other <br />SEDIMENT CONTROL <br />Seiiiment pond construction has been completed in accordance with plans submitted to and approved by the <br />DnQG and as-constructed survey/drawings certified by Registered Land Surveyor and Registered <br />Professional Engineer. All surface rumoff from the fill azea is directed to this sediment control facility <br />known as Pond 7. No significant erosion was observed during this inspection. <br />Sl?RFACE DRAINAGE <br />Armored Ditches line the east and west boundary of the fill area. Lateral ditches on the fill face direct <br />runoff to these side ditches. A fourth east-west ditch was constructed at the upper most extent of the fill, <br />conrtecting to both armored ditches on the east and west perimeters. No erosional problems were noted at <br />the. intersections of the lateral ditches and the armored ditches. <br />SI'pE PREPARATION <br />As indicated in previous inspection reports, organic materials such as brush and trees were removed from <br />the proposed fill area followed by topsoil removal prior to fill placement Design criteria did not require <br />keyway cuts for steeper valleys with minimal soil cover (fill #7). No evidence of springs or seeps was <br />observed during site preparation. <br />DRAINAGE SYSTEM (UNDERDRAINS) <br />Drain sizes aze specified by CDMG regulations for fills which can be classified as Valley Fills. Fill area #7 <br />is not a valley fill. CTL Thompson recommended a minimum 6' x 12' triangular section(area = 64 SF) for <br />this size fill. As indicated by previous inspection reports, as constructed drainages generally were more <br />trapezoidal with a top width of 12', bottom width of 8', and average height of 8' (area = 80 SF). Sandstone <br />recovered from durable "channel" sandstone deposits encountered during [he mining process were used in <br />drain construction. Mirafi 160 fabric was used in lieu of filter material. <br />