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INSPECTION OF EXCESS SPOIL FILL <br />-- First Qttatter 2006 Certification <br />Fill Area No. 7 <br />Date: Match 29.2006 <br />GENERAL DESCRIPTION OR REFERENCE TO SITE PLAN: <br />The CTL Thompson report dated April 27, 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 />Installation of Surface Drahtage System <br />Construction of Fil] <br />Placement of Topsoil <br />-Seeding <br />X Other None -Facility idle throughout the quarter <br />SEDIMENT CONTROL <br />Sediment pond construction has been completed in accordance with plans submitted to and approved by the <br />DMG and as-conswcted survey/drawings certified by Registered Land Surveyor and Registered <br />Professional F.ngiaeer. A$ surface runoff from the fill area is dirceted to this sediment control facility <br />known as Pond 7. No erosional problems were noted during this inspection Pond was dry. Limited early <br />vegetation being gazed down by e0c <br />SURFACE DRAINAGE <br />Armored Ditches line the east and west boundary of the fill area Lateral ditches on the fill face direct <br />nmoff to these side ditches. A fourtlteast-west ditch was constnrcted at the upper most eaTent of the fill, <br />connecting 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. 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 stceper valleys with minimal soil cover (fill #7). No evidence of springs or seeps was <br />observed during site preparation. <br />DRAINAGE SYSTEM (UND$RDRAINS) Drain sizes are specified by CDMG regulations for fills which <br />can be classified as Valley Fi1Ls. FiU 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, ss <br />censfntcted drainages generally were more trapewidal wilt 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 />-ettr~untered during the mining process was used in drain construction. Mirafi 160 fabric was used in lieu of <br />filter material. <br />