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INSPECTION OF EXCESS SPO]Q. FII.L <br />First Quarter 2006 Certification <br />Fill Area No. 9 <br />Date: March 29.2006 <br />GENERAL DESCRIPTION OR REFERENCE TO SITE PLAN: <br />The CTL Thompson report dated April 27, 2001, "Stability Analysis and Geo-technical Recommendations <br />I,orencito Surface Mine Phase I" addresses the general requirements as also cited in Sections 4.09.1 to <br />4.09.2 ofthe Colorado Mined Land Reclamation Board for Coal Mining. <br />AC'T'IVITY DURING INSPECTION: <br />Removal of Topsoil and Organic Matter <br />Placemein of Under-drains. <br />-Installation of Surface Drainage System <br />_Coashuctlon of Fill <br />-Placement of Topsoil <br />-Seeding <br />X Other Facility idle throuettout 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-constnrcted survey/drawings certified by Registered Land Surveyor and Registered <br />Professional Engineer All surface run-off from the fill areas is directed to this sedhnent control facility <br />known as pond 7. Pond 9A was dry at time of inspection. <br />SURFACE DRAINAGE <br />Armored Ditches line the east and west boundary of the fill area. Lateral ditches on the fill face direct <br />rtmoff to these side ditches. No erosional problems were noted at the intersections of the lateral ditches a~ <br />the armored'ditches. <br />Repairs to the surface drainage system were examined as part of this inspection. All repahs were found to <br />comply with specifications contained in ffie original design plans. <br />SITE PREPARATION <br />As indicated by previous inspection repom, organic materials such as brush and trees were removed from <br />the proposed 511 area followed by topsoil removal prior to fill placement Desi@a criteria did not require <br />keyway cuts for steeper valleys with minimal soil cover (511 #9). No evidence of springs or seeps was <br />observed during sike 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 6lL 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 more <br />trapezoidal with a top width of 12', bottom width of 8', and average height of 8' (area = 80 SF). Sandstone <br />recovered from durable "channel" sandstone deposits eacoumered during the mining process were used in <br />• . drain t:onstmction. MitaS 160 fabric was used in lieu of filter material <br />