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INSPECTION OF EXCESS SPOIL FILL <br />Second Quarter 2014 Certification <br />Fill Area No. 9 <br />Date: June 16, 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. All <br />surface run -off from the fill area is directed to this sediment control facility known as Pond 9A. No Discharge has <br />occurred during this quarter. Pond is holding no water and is functioning in good order. Two of the terraces on the <br />fill have spots that need to be cleaned of sediment. These are scheduled to be cleaned in the next few weeks. <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. No erosional problems were noted at the intersections or along the lateral ditches and the <br />armored ditches. Slopes are well vegetated and no erosional problems were observed at the time of this <br />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 #9). 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 #9 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 drainage generally were more trapezoidal with a top <br />width of 12', bottom width of 8', and averaged height of 8' (area > 80 SF). Sandstone recovered form durable <br />"channel" sandstone deposits encountered during the mining process were used in drain construction. Mirafi 160 <br />fabric was used in lieu of filter material. <br />