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INSPECTION OF EXCESS SPOIL FILL <br />~.- Pouth Quarter 2004 Certification <br />Pill Area No. 9 <br />Date: December 30, 2004 <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. I 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 ofUnder-drains <br />Installation of Surface Drainage System <br />~Construc[ion of Fill <br />-Placement of `Topsoil <br />-Seeding <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 areas is directed to this sediment control facility <br />- known as pond 7. Occasional precipitatiwt as snowfall during the fourth quarter resulted in no run-off or <br />erosion to the facility. <br />SURFACE DRAINAGE <br />Armored Ditches liee the east and west boundary of the fill area. Lateral ditches on the till face direct <br />runoff to these side ditches. Some ofthe large rock armoring the down drains was displaced by a third <br />quarter storm event. This rock has since been redistributed returning the channel profile to design <br />configuration. Additional rock is scheduled for placement. No erosional problems were noted at the <br />intersections of the lateral ditches and the at'mored ditches <br />SITE YRI;PARATION <br />As indicated by 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 (till 119). <br />DRAINAGE SYSTEM (UNDERDRAINS) <br />Drain sizes are specified by CDMG regulations fbr fills which can be classified as Valley Fills. Fill area 119 <br />is not a valley fill. CTL Thompson recommended a minimmn 6' x 12' triangular section(area = 64 SF) for <br />this size fill. As indicated by previous inspection reports, as constructed drainages generally were more <br />trapezoidal with a lop width of 12', bottom width of 8', and average height of 8' (area = SO SF). Sandstone <br />recovered from durable "chamtel" sandstone deposits encountered during the mining process was used in <br />drain construction. Mirafi 160 fabric was used in lieu of filter material. <br />