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<br />INSPECTION OF EXCESS SPOIL PILL <br />First Quarter 2004 Certification <br />Fill Area No. 8 <br />Date: March 30, 2004 <br />GENERAL DESCRIPTION OR REFERF,NCE TO SITF, 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 llURING INSPECTION: <br />Removal ofTopsoil and Organic Matter <br />Placement ofUnder-drains <br />Installation of Surface Drainage System <br />Construction of Fill <br />_Placement of Topsoil <br />_Seeding <br />X Other Area idle <br />SEDIMENT CONTROL <br />t Sediment pond construction has been completed in accordance with plans submitted [o 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 areas is directed to this sediment control facility <br />also known as Pond 8. No evidence of significant erosion was observed. <br />S[TE PREPARATION <br />As indicated by previous inspection reports, organic materials such as brush and trees were removed fi'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 #8). 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 fills which can be classified as Valley Fills. Fill area #8 <br />is a valley fill. CTL Thompson recommended a minimwn 6' x 12' triangular section(area = 64 SP) 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. MiraG 160 fabric was used in lieu of filter material. <br />FILL PLACEMENT <br />Fill material was reworked down-slope to allow placement of compacted lifts on the oulslope of the fill. <br />Four benches were defined and drainage established laterally to the side drainage system. Down drains <br />have been established and rip-rapped. Additional work is needed especially at the intersections of the <br />lateral ditches and the armored downdrains <br />