2008-07-18_PERMIT FILE - M2008006

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Adr. Gary DeWitt RE: SerFer Pit July 3, 2008 Page 4 of 4 Due to the fact that the ditch lies partially within the planned reclamation area, it is anticipated that the ditch will need to be removed in order to line the reservoir. According to the drainage report, this ditch conveys the off- site stormwater to the Poudre River. The drainage report indicates that during most storm events, off-site flows that are routed on to the Site enter through a 36" RCP under HWY 392. The 36" RCP has limited capacity because of sediment buildup. As a result, the drainage report indicates that during a 100-year flood event the limited capacity of the 36" RCP, along with other factors, will most likely cause stormwater to overtop HWY 392 and enter the Site along the northeast property line. However, the design of the stormwater ditch is based on the assumption that the 36" RCP will be free from any obstruction and operating at full capacity. Because the existing ditch location lies in the proposed mining area and does not provide ideal conveyance to the Poudre River, the drainage report provides an alternate stormwater conveyance from the 36" RCP to the Poudre River. The proposed conveyance will run approximately along the western permit boundary to the Poudre River. The calculations in the drainage report show that the proposed channel is not expected to divert flood water onto MOT ROW. A copy of the slope stability report for the embankments and adjacent ditch is included as an attachment to this letter. Should you have any questions or desire further clarification, please contact our office at 303- 452-6611. - -Sincere y Applegate Group -Inc. Ty Thompson Natural Resource Specialist TAT/ta cc: John Warren, Connell Resources, Inc. Joe A. Intermill, Jr AG File No. 07-122 NA07122 Connell Resources 392 & CROMisciplines (Technical)\Mine Planning\Objector Letters\CDOT Response.docx