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INSPECTION OF EXCESS SPOIL PILL <br />~, Fourth Quarter 2004 Certification <br />Fill Area No. 8 <br />Date: December 30, 2004 <br />GENERAL DESCRIPTION OR I2EFERENCF, 4'O SI'PE PLAN: <br />The CTL Thompson report dated April 27, 2001, "Stability Analysis and Geo-technical Recommendations <br />Lorencito Surface Mine Phase 1" 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 ofUnder-drains <br />Installation of Surface Drainage System <br />Construction of Pill <br />_Placement of Topsoil <br />Seeding <br />X Other None, facility was idle tbrouehout the fourth yuartcr <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. No surface run-off has occun'ed during the quarter and no erosion was noted on the <br />surfaces of the spill embankments. <br />SITE PREPARATION <br />As indicated by previqus inspection reports, organic materials such as brush and frees were removed 6~om <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 H8). No evidence of springs or seeps was <br />observed during site preparation. <br />DRAINAGE SYSTEM (UNDERURAINS} <br />Drain sizes are specified by CDMG regulations for tills which can be classified as Valley Fills. PiII area t/8 <br />is a valley fill. CTL Thompson recommended a minimum 6' x 12' triangular section(area = C>4 SP) for this <br />size fill. Under-drain system was extended down slope to allow establishing the designed slope criteria fur <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. MiraG 160 fabric was used in lieu of filter material. <br />FILL PLACEMENT <br />Fill material placement has been completed in accordance with the approved plan. <br />