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INSPECTION OF EXCESS SPOII, FILL <br />First Quarter 2005 Certification <br />Fill Area No. 9 <br />Date: March 30. 2005 <br />GENERAL DESCRIPTION OR REFERENCE TO SITE PLAN: <br />The CTL Thompson report dated Apri127, 2001, "Stability Analysis and Geo-technical Recommendations <br />Lorencito Surface Mine Phase P' 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 of Underdrains <br />Installation of Surface Drainage System <br />Construction of Fill <br />Placement of Topsoil <br />-Seeding <br />SEDIMENT CONTROL <br />Sediment pond construction has been completed in accordance with plans submitted to and approved by <br />the DMG and as-constntcted survey/drawings certified by Registered Land Surveyor and Registered <br />Professional Engineer. All surface nmoff from the fill areas is directed [o this sediment convol facility <br />known 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. Some of the lazge rock armoring the down drains was displaced during a 100 <br />yr-24 hr storm event in August of 2004. This rock has since been redistributed retwning the channel <br />profile to design configuration. Additional rock was placed along the west down drain during this <br />quarter. No erosional problems were noted at the intersections of the lateral ditches and the armored <br />ditches <br />SITE PREPARATION <br />As indicated by previous inspection reports, organic materials such as brash and veer were removed from <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 #9). <br />DRAINAGE SYSTEM (UNDERDRAINS) <br />Drain sizes are specified by CDMG regulations for fills which can be classified as Valley Fills. Fi]] area <br />#9 is not a valley fill. CTL Thompson recommended a minimum 6' x 12' triangulaz section(area = 64 <br />SF) for this size fill. As indicated by previous inspection reports, as constructed drainages generally were <br />more trapezoidal with a top width of 12', bottom width of 8', and average height of 8' (area = 80 SF). <br />Sandstone recovered from durable "channel" sandstone deposits encountered during the mining process <br />were used in drain constmction. Mirafi 160 fabric was used in lieu of filter material. <br />