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INSPECTION OF EXCESS SPOIL FILL <br />First Quarter 2005 Certification <br />Fill Area No. 7 <br />Date: Mazch 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 Boazd 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 />X Other Repair of Armored Downdmins <br />SEDIMENT CONTROL <br />Sediment pond construction has been completed in accordance with plans submitted to and approved by <br />the DMG and as-constructed survey/drawings certified by Registered Land Surveyor and Registered <br />Professional Engineer. All surface runoff from the fill area is directed to this sediment control facility <br />known as Pond 7. No significant erosion was observed during this inspection. <br />SURFACE DRAINAGE <br />Armored Ditches line the east and west boundary of the fill azea. Lateral ditches on the fill face direct <br />runoff to these side ditches. A fourth east-west ditch was censtructed at the upper most extent of the fill, <br />connecting to both armored ditches on the east and west perimeters. Damage to the drainage system <br />occurred in August of 2004 from high flows resulting from a storm exceeding the 100yr-24 hour storm <br />event. The drainage channels were restored as soon after the storm event as conditions allowed. <br />Additional rock armoring was completed during this quarter. <br />SITE PREPARATION <br />As indicated in previous inspection reports, organic materials such as brush and trees 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 #7). 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 511s which can be classified as Valley Fills. Fill azea <br />#7 is not a valley fill. CTL Thompson recommended a minimum 6' x 12' triangular 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' (azea = 80 SF). <br />Sandstone recovered from durable "channel" sandstone deposits encountered during the mining process <br />were used in drain construction. Mirafi 160 fabric was used in lieu of filter material. <br />