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INSPECTION OF EXCESS SPOIL FILL <br />Fourth Quarter 2006 Certification <br />Fill Area No. 9 <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-[echnical 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 Undervdrains <br />Installation of Surface Drainage System <br />_Construction of Fill <br />Placement of Topsoil <br />Seeding <br />X Other Facility idle -reclamation durine Aueust and September <br />SEDIMENT CONTROL <br />Sediment pond construction has been completed in accordance with plans submittbd to and approved by the <br />DMG and as-constructed survey/drawings certified by Registered Land Surveyor and Registered <br />Professional Engineer. All surface runoff from the fill areas is directed to this sediment control facility <br />(mown 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 area. Lateral ditches on the fill face direct <br />runoff to these side ditches. No erosional problems were noted at the intersectioas of the lateral ditches and <br />the armored ditches. 'Rte main access road across the mine distrnbance area was relocated and now crosses <br />along the crest of fill 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 such as bnuh and trees were removed from <br />the proposed fill area followed by topsoil removal prior to fill placement Design cri0eria did not require <br />keyway cots for steeper valleys wilt minimal soil cover (511 tl9). 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 5ll. CTL Thompson recommended a minimum 6' x 12' triangular section area = 64 SF) for <br />this size S1L As indicated by previous ~tian reports, as constructed drainages generally were more <br />trapewidal with a top width of 12', bottom width of 8', and average height of 8' (area = 80 SF). Sandstone <br />recovered from durable "charnel" sandstore deposits encountered during the mining process were used in <br />drain construction. MiraS 160 fabric was used in lieu of Sher material. <br />