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INSPECTION OF EXCESS SPOIL FILL <br />First Quarter 2007 Certification <br />Fill Area No. 8 <br />Date: March 30.2007 <br />GENERAL DESCRIPTION OR REFERENCE TO SITE PLAN: <br />The CTL Thompson report dated Apri127, 2001, "Stability Analysis and Geo-techmical Recommendations <br />Lorencito Surface Mine Phase I^ addresses the general requvemems as also cited in Sections 4.09.1 to <br />4.09.2 of the Colorado Mined Land Reclamation 13oazd for Coal Mining. <br />ACTIVITY DURING <br />Removal of Topsoil and Organic Matter <br />-Placement of Underdrains <br />-Installation of Surface Drainage System <br />_Constuction of Fill <br />-Placement of Topsoil <br />-Seeding <br />X Otlrer Facility idle <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 certi5ed by Registered Iand Surveyor and Registered <br />Professional Engineer. All surface nm-off from the fill area is directed to this sediment control facility also <br />lmown as Pond 8. The pond was observed discharging on August 3 and 29, 21106 and the regained sampling <br />was completed. The requQerl DMR will be filed with the Colorado Department of Public Health and <br />Emvhomnem widr a copy to the Division of Reclamation, Mining and Safety. <br />SURFACE DRAINAGE <br />Armored Ditches line the east and west boundary of the fill area Lateral ditches on the fill face direct runoff <br />to these side ditches. No erosional problems were noted along the lateral ditches and the two armored <br />ditches. Slopes have become well vegetated and no erosional problems were noted. <br />STTE PREPARATION <br />As indite by previous inspection reports, organic materials such as brush and trees were removed from <br />the proposed fill area followed by topsoil removal prior to fill placement. Design criteria did not requne <br />keyway cuts for steeper valleys with minimal soil cover (fill #8). No evidence of springs or seeps was <br />observed during site pteparatiotr. <br />DRAINAGE SYSTEM fUNI1ERDRAINS) <br />Drain sizes are specified by CDMG regulations for fills which can be classified as Valley Fills. Fill area #8 <br />is a valley fill. CTL Thompson recommended a minimum 6' x 12' triangular sedirn(area = 64 SF) for this <br />size fill. Under rain system was extended down slope to allow establishing ffie designed slope criteria for <br />the final slope (assmr!ir!g no resumption of mining). The typical d®ensions of the extended drainage <br />generally were more trapezoidal with a top width of 10', bottom width of 14', and average height of 8' (area <br />> 96 SF). Sandstone recovered from durable "charnel" sandstone deposits encamtered during the miming <br />process were used in dram construction M;cafi 160 fabric was used in 6eu of filter material. <br />