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INSPECTION OF EXCESS SPOIL FILL <br />First Quarter 2006 Certification <br />FiII Area No. 8 <br />Date: March 29.2006 _ <br />GENERAL DESCRIPTION OR REFERENCE TO SITE PLAN: <br />The CTL Thompson report dated April 27, 2001, °Stability Analysis and Geo-techrtical 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 aad Organic Matter <br />Placemem of Undervdrains <br />Iostallatian of Surface Drainage System <br />_Construction of Fill <br />-Placement of Topsoil <br />-Seeding <br />X Other Facility idle dtrouehout the quarter <br />SEDIlY[ENT CONTROL <br />Sedimert pond construction has been completed in accordance with plans submitted to and approved by the <br />DMG and asconstructed survey/drewings certified by Registered Land Surveyor and Registered <br />Professional Engineer. All surface nm-0ff from the fill area is directed to this sediment control facility also <br />known as Pond 8. <br />SURFACE DRAINAGE <br />Armored Ditches tine the east and west beundary of the fill area. Lateral ditches on the fill face direct nmoff <br />to these side ditches. Grading and resceding of the lateral ditches remains to be completed. This does not <br />impact their functionality. <br />SITE PREPARATION <br />As indicated by previous inspection reports, organic materials such as brush and trews were removed from <br />the proposed fi@ area foflowed 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 (UNDERDRATNS) <br />Drain sizes are specified by CDMG regulations for fills which can be chussified 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 fnual slope (assu+ing no resu®ption of mining). The typical dimensions of dre 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 rewvered fiotn durable °channeP' sandstone deposits encountered duuing the mining <br />:...process were used in drain construction. Mirafi 160 fabric was used in lieu of Sher material. <br />