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INSPECTION OF EXCESS SPOIL FILL <br />First Quarter 2009 Certification <br />Fill Area No. 8 <br />Date: March 10, 2009 <br />GENERAL DESCRIPTION OR REFERENCE TO SITE PLAN: <br />The CTL Thompson report dated April 27, 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 of Under-drains <br />-Installation of Surface Drainage System <br />-Construction of Fill <br />-Placement of Topsoil <br />-Seeding <br />X Other 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 certified by Registered Land Surveyor and Registered <br />Professional Engineer. All surface run-off from the fill area is directed to this sediment control facility also <br />known as Pond 8. Pond 8 discharged as a result of a storm event in August of this quarter. <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. The East armored ditch <br />is starting to erode out of the channel between the lower and second bench. Slopes have become well <br />vegetated and no other erosional problems were noted. <br />SITE PREPARATION <br />As indicated 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 require <br />keyway cuts for steeper valleys with minimal soil cover (fill #8). 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 #8 <br />is a valley fill. CTL Thompson recommended a minimum 6' x 12' triangular section(area = 64 SF) for this <br />size fill. Under-drain system was extended down slope to allow establishing the designed slope criteria for <br />the final slope (assuming no resumption of mining). The typical dimensions 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 "channel" sandstone deposits encountered during the mining <br />process were used in drain construction. Mirafi 160 fabric was used in lieu of filter material.