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INSPECTION OF EXCESS SPOIL FII.L <br />Second Quarter 2005 Certification <br />Fill Area No. 9 <br />Date: June 27, 2005 <br />GENERAL DESCRIPTION OR REFERENCE TO STTE PLAN: <br />The CTL Thompson report dated Apri127, 2001, "Stability Analysis and Geo-techniral Recommendations <br />Lorencito Surface Mine Phase I" addresses the general requirements as also cited in Sections 4.09.1 to <br />4.092 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 />_htstallation of Surface Drainage System <br />Construction of Fill <br />Placement of Topsoil <br />Seeding <br />X Outer Certification of Repairs to the Surface Drainage System <br />SEDIMENT CONTROL <br />Sediment pond construction has been completed in accordance with plans submitted to and approved by the <br />DMG and as-constmcted survey/drawings certi5ed by Registered Land Surveyor and Registered <br />Professional Engineer. All surface runofffrom the fill areas is directed to this sediment control facility <br />lmown as pond 7. <br />SURFACE DRAINAGE <br />Armored Ditches line the east and west boundary of the fill area. Lateral ditches on the fill face direct <br />runoff to these side ditches. No erosional problems were noted at the intersections of the lateral ditches and <br />the armored ditches. <br />Repairs to the surface drainage system were examined as part of this inspection. All tepaus were found to <br />compty with specifications contained in the original design plans. <br />STTE PREPARATION <br />As indicated by previous inspection reports, organic materials such as brush and trees were removed from <br />the proposed fill area followed by topsoil removal prior to 5ll placement Design criteria did not require <br />keyway cuts for steeper valleys with minimal soil cover (fill #9). 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 #9 <br />is not a valley 511. CTL Thompson recommended a minimum 6' x 12' triangular section(area = 64 SF) for <br />this size fill. As indicated by previous inspection reports, as constructed drainages generally were mare <br />trapezoidal with a top width of 12', bottom width of 8', and average height of 8' (area = 80 5F). Sandstone <br />recovered from durable °channel" sandstone deposits encountered during the mining process were used in <br />drain construction. Mitafi 160 fabric was used m lieu of filter material. <br />