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INSPECTION OF EXCESS SPOIL FILL <br />First Quarter 2014 Certification <br />Fill Area No. 7 <br />Date: March 25, 2014 <br />Page: 1 of 2 <br />GENERAL DESCRIPTION OR REFERENCE TO SITE PLAN: <br />The CTL Thompson report dated April 27, 2001, "Stability Analysis and Geo- technical Recommendations Lorencito <br />Surface Mine Phase 1" addresses the general requirements as also in Section 4.09.1 to 4.09.2 of the Colorado <br />Mined Land Reclamation Board for Coal Mining. <br />ACTIVITY DURING INSPECTION: <br />_Removal of Topsoil and Organic Matter _Placement of Under - drains <br />_Installation of Surface Drainage System _Construction of Fill <br />_Placement of Topsoil _Seeding <br />X Other Facility in Final Reclamation — Phase 1 Released <br />SEDIMENT CONTROL <br />Sediment pond construction has been completed in accordance with plans submitted to and approved by the DMG <br />and as- constructed survey \drawings certified by a Registered Land Surveyor an \or a Professional Engineer. Ali <br />surface run -off from the fill area is directed to this sediment control facility known as Pond 7. No Discharge has <br />occurred during this quarter. Pond is holding a limited amount of water and is functioning in good order. <br />SURFACE DRAINAGE <br />Armored Ditches line the east and west boundary of the fill area. Lateral ditches on the fill face direct runoff to <br />these side ditches. A fourth east -west ditch was constructed at the upper most extent of the fill, connection to <br />both armored ditches of the east and west perimeters. No erosional problems were noted at the intersections of <br />the lateral ditches and the armored ditches. Slopes are well vegetated and no erosional problems were observed <br />at the time of this inspection. <br />SITE PREPARATION <br />As indicated in previous inspection reports, organic materials such as brush and trees were removed from the <br />proposed fill area followed by topsoil removal prior to fill placement_ Design criteria did not require keyway cuts <br />for steeper valleys with minimal soil cover (fill #7). No evidence of springs or seeps was observed during site <br />preparation. <br />DRAINAGE SYSTEM (UNDERDRAINS) <br />Drain sizes are specified by CDMG regulations for fills which can be classified as Valley Fills. Fill area #7 is not a <br />valley fill. CTL Thompson recommended a minimum 6'x 12' triangular section (area = 64 SF) for this size fill. As <br />indicated by previous inspection reports, as constructed drainages generally were more trapezoidal with a top <br />width of 12', bottom width of 8, and average height of 8' (area = 80SF). Sandstone recovered from durable <br />'channel" sandstone deposits encounter during the mining process was used in drain construction. Mirafi 160 <br />fabric was used in lieu of filter material. <br />