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INSPECTION OF EXCESS SPOIL FILL <br />Fourth Quarter 2003 Certification <br />Fill Area No. 7 <br />Date: December 30, 2003 <br />GENERAL DESCRIPTION OR RERERENCE TO SITE PLAN: <br />The CTL Thompson report dated Apri127, 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 ofUnder-drains <br />Installation of Surface Drainage System <br />Construction of Fill <br />_Placement of Topsoil <br />_Seeding <br />X Other Mine idle - no activity during this 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-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. No <br />significant erosion was observed during this inspection. <br />SITE PREPARATION <br />As indicated in 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 no[ require <br />keyway cuts for steeper valleys with minimal soil cover (fill #7). 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 #7 <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' (azea = 80 SF). Sandstone <br />recovered from durable "channel" sandstone deposits encountered during [he mining process were used in <br />drain construction. Mirafi 160 fabric was used in lieu of filter material. <br />FILL PLACEMENT <br />CDMG regulations require that spoil be "placed in horizontal lifts in a controlled manner, concurrently <br />compacted as necessary to ensure mass stability". Maximum lift thicknesses are not specified. As indicated <br />by previous inspection reports, lifts were placed in accordance with plans specified by CTL Thompson. <br />Spoil material was transported to the fill area using a combination of trucks and dozers. Left thicknesses of <br />up to 50' were placed within the area removed from the fill face by more than 50 ft. Thinner lifts of 6-8 ft. <br />with leveling and compactive effort supplied by dozers and trucks was utilized as fill placement advances [o <br />within fifty feet of the slope face. No fill placement occurred during this quarter. <br />