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INSPECTION OF EXCESS SPOIL FILL <br />• Second Quarter 2006 Certification <br />Fill Area No. 8 <br />Date: Jtme 12, 2006 <br />GENERAL DESCRIPTION OR REFERENCE TO SITE PLAN: <br />The CTL Thompson report dated Apri127, 2001, "Stability Analysis and Geo-technical Recommendations <br />Lorencito Surface Mine Pbase I" addresses the general requirements as also cited in Sections 4.09.1 to <br />4.09.2 of the Colorado Mined Land Reclamation $oard for Coal Mining. <br />ACTIVITY DURING INSPECTION: <br />-Removal of Topsoil and Organic Matter <br />-Placement of Under-drains <br />_Installatian of Sur6ce Drainage System <br />Construction of Fill <br />-Placement of Topsoil <br />Seeding <br />X Other Faciliri idle throughout the quarter <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/dmwmgs certified by Registered band Surveyor and Registered <br />Professional Engineer. All surface runoff from the fill area is directed to this sediment control facility also <br />• lmown as Pond 8. <br />SURFACE DRAINAGE <br />Armored Ditches finis the east and west boundary of the fill area. Lateral ditches on the fill face direct runoff <br />to these side ditches. Grading and reseeding of the Lnernl ditches remains to be completed. This does not <br />impact their functionality. <br />SITE PREPARATION <br />As indicated by previous inspection reports, organic mat.~at~ such as brush and bees were removed from <br />the proposed fill area followed by topsoil removal prior to 511 placement Design criteria did not require <br />keyway cuts for steeper valleys with min®al soil cover (&ll #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 5ll. 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 dram construction. Mimfi 160 fabric was used in fieu of Sher material. <br />