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INSPECTION OF EXCESS SPOIL FILL <br />Fourth Quarter 2006 Certification <br />Fill Area No. 7 <br />Date: December 26, 2006 <br />GENERAL DESCRIPTION OR REFERENCE TO SITE PLAN: <br />The CTL Thompson report dated April 27, 2001, "Stability Analysis and Geo-technical P.ecommendations <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 Underdrains <br />-Installation of Surface Drainage System <br />_Construction of Fill <br />_Placemert of Topsoil <br />-Seeding <br />X Other Faciliri 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 nmofftirom 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 ofthe fill area Lateral ditches on the till face direct <br />runoff to these side ditches. A fourth east-west ditch was constructed at the upper most edent of the fill, <br />connecting to both armored ditches on are east and west perimeters. No erosional problems were noted at <br />the inte[xctions 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 bnrsh and trees were removed from <br />the proposed fill area followed by topsoil removal prior to fill placement Design criterur did not require <br />keyway certs for steeper valleys with minimal soil cover (fill #7). No evidence of spring`, or seeps was <br />observed dm~ing site preparation. <br />DRAINAGE SYSTEM (UNDERDRAINS) Drain sizes are specified by CDMG regulations for fills which <br />can be classified as Valley FiOs. Fill area #7 is not a valley till. CTL Thompson recomrnended a minimum <br />6' x 12' triangular section (area = 64 SF) for this siu fill As indicated by previous inspection reports, as <br />constructed drainages generally were more trapemidal wit& a top width of 12', bottom vndth of 8', and <br />average height of 8' (area = 80 SF). Sandstone recovered from durable "channel" sand:~Wne deposits <br />encountered during the mining process was used in drain com~trnction Mhafi 1G0 fabric. was used in lieu of <br />filter material. <br />