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<br /> <br />INSPECTION OF EXCESS SPOIL FILL <br />Second Quarter 2005 Certification <br />Fill Area No. 7 <br />Date: June 27.2005 <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 Board for Coal Mining. <br />ACTIVITY DURING INSPECTION: <br />Removal of Topsoil and Organic Matter <br />Placement of Under-drains <br />Installatron of Surface Drainage System <br />_Construction of Fill <br />Placement of Topsoil <br />X Seeding <br />X Other Certification of Reoairs to the Surface Drainage System <br />SEDIMENT CONTROL <br />Sediment pond constmction has been completed in accordance with plans submitted to and approved by the <br />DMG and as-constmcted survey/drawings certified by Registered Land Surveyor and Registered <br />Professional Engineer. All surface nmoff from the fill area is directed to this sediment control facility <br />known as Pond 7. No significant erosion was observed during this inspection. <br />SURFACE DRAINAGE <br />Armored Ditches line the east and west boundary of the fill area. Lateral ditches on the fill face direct <br />runoffto these side ditches. A fourth east-west ditch was constructed at the upper most extent of the SII, <br />connecting to both armored ditches on the east and west perimeters. <br />Repairs to the surface drainage system were examined as part of this inspection. All repahs were found to <br />comply with speciScations contained in the original design plans. <br />SITE PREPARATION <br />As indicated in previous inspecKion 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 mininrai soil cover (fill #7). No evidence of springs or seeps was <br />observed during site preparation. <br />DRAINAGE SYSTEM (UNDERDRAINS) <br />Drain sizes are specified by CDMG regulations for fills which cao be chtssified as Valiey 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 />Ibis size fill. As indicand 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 the mining process were used in <br />drain construction Mimfi 160 fabric was used in lieu of Sher material. <br />