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INSPECTION OF EXCESS SPOIL FILL <br />First Quarter 2007 Certification <br />Fill Area No. 9 <br />Date: March 30.2007 <br />GENERAL DESCRIPTION OR REFERENCE TO SITE PLAN: <br />The CTL Thompson report dated April 27, 2001, "Stability Analysis and Geo-tecLnical Recommcedations <br />Lorencito Surface Mine Phase I^ addresses the geperal requuemcets as also cited in Sections 4.09.1 to <br />4.092 of the Colorado Mined Land Reclamation Board for Coal Mining. <br />ACTMTY DURING INSPECTION: <br />Removal of Topsoil and Organic Matter <br />_Placemert of Underdrams <br />_Instalhnioo of Surfice Drainage System <br />_Construc[ion of Fill <br />-Placement of Topsoil <br />Seeding <br />X Other Facility idle -reclamation diving August and September <br />SEDIMENT CONTROL <br />Sedimern pond construclion has been completed in accordance with plans submitted to and approved by the <br />DMG and as-constructed survey/drawings ceRiSed by Registered Land Surveyor and Registered <br />Professional Engineer All surface runoff from the 51l areas is directed to this sed®eat control facility <br />known as pond 9A. Pond 9A held water to about 2 feet below the lowest weep hole at time of inspection. <br />SURFACE DRAINAGE <br />Armored Ditches lice the east and west boundary of the 511 area. Lateral ditches on the 511 face direct <br />runoff to these side ditches. No erosional problems were noted at the intersections of the lateral ditches and <br />the armored ditches. The main access road across the mine disturbance area was relocated and now crosses <br />along the crest of Sll 9. A concrete culvert was installed at the head of the west down drain at the point <br />where the road crosses the drainage. <br />SITE PREPARATION <br />As indicated by previous inspection reports, organic materials surd as brash and trees were removed from <br />the proposed fill area followed by topsoil removal prior to 5ll placement Design criteria did not require <br />keyway cuts for steeper valleys with mm®al soil cover (511 #9). No evidence of springs or seeps was <br />observed during site preparation. <br />DRAINAGE SYSTEM (UNDERDRAINS) <br />Drain sizes are specified by CDMG regulations 5x fills which can be classi5ed as Yalley Fills. Fill area H9 <br />is not a valley SIL CTL Thompson recommended a miuim~mt 6' x 12' triangular section(area = 64 SF) for <br />this size fill. As indicated by previous inspection reywrts, as constructed drainages generally were more <br />trapezoidal witlr a top width of 12', bottom width of 8', and average height of 8' (area = 80 SF). Sandstone <br />recovered 5om durable "cham.el" sandstone deposits epcormtered diving the mining process were used'm <br />drain construction. Mirafi 160 fabric was used in lieu of 51ter material. <br />