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<br />• <br />• <br />ill illllliiilllllll <br />999 <br /> <br />DISPOSAL OF EXCESS Ste, <br />Fourth Quarter 2001 Certification <br />Fill Area #9 <br />9F~Fi <br />/q CFO <br />°~~. NS's <br />'giOf'h~P, ?p0? <br />TSB <br />C~~cbe <br />The CTL Thompson report dated April 27, 2001, "Stability Analysis and Geotechnical 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 />SEDIMENT CONTROL <br />Sediment pond construction has been completed in accordance with plans submitted to and approved by <br />the DMG and as-constructed survey/drawings certified by Registered Land Surveyor and Registered <br />Professional Engineer. All surface run-off from [he fill areas is directed to this sediment control facility. <br />SITE PREPARATION <br />Organic materials such as brush and trees were removed from the proposed fill area followed by topsoil <br />removal. Design criteria did not require keyway cuts for steeper valleys with minimal soil cover (fill #9). <br />No evidence of springs or seeps was 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 constructed drainages generally were more trapezoidal with a top width of 12', bottom <br />width of 8', and average height of 8' (area = 80 SF). Sandstone recovered from durable "channel" <br />sandstone deposits encountered during the mining process were used in drain construction. Mirafi 160 <br />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 aze not specified. Lifts were <br />placed in accordance with plans specified by the CTL Thompson report, <br />Spoil material was transported to the fill area using a combination of trucks and dozers. Left thicknesses of <br />upto 50 feet were placed within the area removed from the fill face by more than 50 feet. Thinner lifts of 6 <br />to 8 feet with leveling and compactive effort supplied by dozers and trucks will be utilized as fill placement <br />advances to within fifty feet of the slope face. <br />COVER MATERIAL <br />Final fill configuration has not been obtained and no cover material placed on the excess spoil. <br />Fill No. 9 Page 1 of 2 <br />