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INSPECTION OF EXCESS SPOIL FILL <br />First Quarter 2015 Certification <br />Fill Area No. 8 <br />Date: March 24, 2015 <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 8. No Discharge has <br />occurred during this quarter. Pond is functioning in good order with minimal sediment. Pond is holding minimal <br />water at the time of the inspection. <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 48). 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 #8 is not a <br />valley fill. CTL Thompson recommended a minimum 6' x 12' triangular section (area = 64 SF) for this size fill. Under - <br />drain system was extended down slope to allow establishing the designed slope criteria for the final slope <br />(assuming no resumption of mining). The typical dimensions of the extended drainage generally were more <br />trapezoidal with a top width of 10', bottom width of 14', and averaged height of 8' (area > 96 SF). Sandstone <br />recovered form durable "channel" sandstone deposits encountered during the mining process were used in drain <br />construction. Mirafi 160 fabric was used in lieu of filter material. <br />