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INSPECTION OF EXCESS SPOIL FILL <br />First Quarter 2008 Certification <br />Fill Area No. 7 <br />Date: April 2, 2008 <br />GENERAL DESCRIPTION OR REFERENCE TO SITE PLAN: <br />The CTL Thompson report dated April 27,200 1, "Stability Analysis and Geo-technical Recommendations <br />Lorencito Surface Mme 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 />-Installation of Surface Drainage System <br />_Construction of Fill <br />-Placement of Topsoil <br />-Seeding <br />X Other Facility idle <br />SEDIMENT CONTROL <br />Sediment pond construction has been completed in accordance with plans submitted to and approved by the <br />DMG and as-constructed survey/drawings certified by Registered Land Surveyor and Registered <br />Professional Engineer. All surface run-off from the fill area is directed to this sediment control facility <br />known as Pond 7. No discharge occurred during the quarter. <br />SURFACE 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 />connecting to both armored ditches on the east and west perimeters. No erosional problems were noted at i <br />the intersections of the lateral ditches and the armored ditches. Slopes have become well vegetated and no <br />erosional problems were noted. <br />SITE 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) Drain sizes are specified by CDMG regulations for fills which <br />can be classified as Valley Fills. Fill area #7 is not a valley fill. CTL Thompson recommended a minimum <br />6' x 12' triangular section (area = 64 SF) for this size fill. As indicated by previous inspection reports, as <br />constructed drainages generally were more trapezoidal with a top width of 12', bottom width of 8', and <br />average height of 8' (area .= 80 SF). Sandstone recovered from durable "channel" sandstone deposits. . <br />encountered during the mining process was used in drain construction. Mirafi 160 fabric was used in lien of <br />filter material.