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INSPECTION OF EXCESS SPOIL FILL <br />Third Quarter 2006 Certification <br />Fill Area No. 9 <br />Date: September 30, 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 Boazd for Coal Mining. <br />ACTIVITY DURDYG INSPECTION: <br />Removal of Topsoil and Organic Matter <br />Placement of Under-drains <br />Installation of Surface Drainage System <br />Conswction of Fill <br />_Placement of Topsoil <br />_Seeding <br />X Other Faciliri idle -reclamation durine August and September <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 azeas is dvected to this sediment 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 line the east and west boundary of the fill azea. Lateral ditches on the fill 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 fi119. 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 such as brush and trees were removed from <br />the proposed fill azea followed by topsoil removal prior to fill placement. Design criteria did not require <br />keyway cuts for steeper valleys with minimal soil cover (fill #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 for fills which can be classified as Valley Fills. Fill area #9 <br />is not a valley fill. CTL Thompson recommended a minimum 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 top width of 12', bottom width of 8', and average height of 8' (area = 80 SF). Sandstone <br />recovered from durable "channel" sandstone deposits encountered during the mining process were used in <br />drain construction. Mirafi 160 fabric was used in lieu of filter material. <br />