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INSPECTION OF EXCESS SPOIL FILL Third Quarter 2003 Certification Fill Area No. 8 Date: September 30, 2003 GENERAL DESCRIPTION OR REFERENCE TO SITE PLAN: The CTL Thompson report dated April 27, 2001, "Stability Analysis and Geo-technical Recommendations Lorencito Surface Mine Phase I" addresses the general requirements as also cited in Sections 4.09.1 to 4.09.2 of the Colorado Mined Land Reclamation Boazd for Coal Mining. ACTIVITY DURING INSPECTION: _Removal of Topsoil and Organic Matter X Placement of Under-drains X Installation of Surface Drainage System X Construction of Fill Placement of Topsoil _Seeding X Other Mine idle SEDIMENT CONTROL Sediment pond construction has been completed in accordance with plans submitted to and approved by the DMG and as-constructed survey/drawings certified by Registered Land Surveyor and Registered Professional Engineer. All surface run-off from the fill areas is directed to this sediment control facility. No evidence of significant erosion was observed. SITE PREPARATION As indicated by previous inspection reports, organic materials such as brush and trees were removed from the proposed fill area followed by topsoil removal prior to fill placement. Design criteria did not require keyway cuts for steeper valleys with minimal soil cover (fill #8). No evidence of springs or seeps was observed during site preparation, DRAINAGE SYSTEM (UNDERDRAINS) Drain sizes are specified by CDMG regulations for fills which can be classified as Valley Fills. Fill area #8 is a valley fill. CTL Thompson recommended a minimum 6' x 12' triangular section(area = 64 SF) for this size fill. Under-drain system was extended down slope to allow establishing the designed slope criteria for the final slope (assuming no resumption of mining). The typical dimensions of the extended drainage generally were more trapezoidal with a top width of 10', bottom width of 14', and average height of 8' (area> 96 SF). Sandstone recovered from durable "channel" sandstone deposits encountered during the mining process were used in drain construction. Mirafi 160 fabric was used in lieu of filter material. FILL PLACEMENT Fill material was reworked down-slope to allow placement of compacted lifts on the outslope of the fill. Four benches were defined and drainage established laterally to the side drainage system. Down drains have been established but not rip-rapped.