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~-- - <br />RL~~9t~1~~ <br />INSPECTION OF EXCESS SPOIL FILL Ju~ 10 ZOO2 <br />First Quarter 2002 <br />~OnofMinerals a G~IOOY <br />Fill Area #8 <br />January 25, 2002 <br />The CTL Thompson report dated April 27, 2001, "Stability Analysis and Geotechnical Recommendations <br />Lorencito Surface Mine Phase I" addresses the genera] 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 />ACTIVITIES NOTED DURING INSPECTION <br />He spill disposal azea was under active construction. Most vegetation had been removed and topsoil was <br />actively being recovered. The under-drain channel had been cut and rock placement completed within the <br />excavated channel, Filter fabric was being installed over the rock under-drains. <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 the fill areas is directed to this sediment control facility. <br />SITE PREPARATION <br />Organic materials such as brush and trees have been removed from the proposed fill areas. Topsoil has <br />been recovered from (with the exception of exempted steep slopes) and stockpiled for use in reclamation of <br />the fill azea. Design criteria did not require keyway cuts for steeper valleys with minimal soil cover (fill <br />#8). <br />No evidence of springs or seeps was observed during site prepazation. <br />DRAINAGE SYSTEM (UNDERDRAINS) <br />Drain sizes are specified by CDMG regulations for fills which can be classified as Valley Fills. FiII area #8 <br />is a valley fill. CTL Thompson recommended a minimum 6' x.12' triangular section(area = 64 SF) for this <br />size fill. As constructed drainages generally were more trapezoidal with a top width of 12', bottom width <br />of 8', and average height of 8' (area = 80 SF). Sandstone recovered from durable "channel" sandstone <br />deposits encountered during the mining process were used in drain construction. Mirafi 160 fabric was <br />used in lieu of filter material. <br />FILL PLACEMENT <br />Significant quantities of fill material have not been permanently placed. <br />COVER MATERIAL <br />Final fill configuration has not been obtained and no cover material placed on the excess spoil. <br />Fill No. 8 Page 1 of 2 <br />