2013-08-15_REPORT - C1981019 (2)

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Interoffice Memorandum To: Rob Zuber From: Zach Trujillo Subject: Colowyo — Second Quarter 2013 West Pit Fill Monitoring Report Date: 08/15/2013 ••• After my review of the 2013 Second Quarter West Pit Fill Monitoring Report for Colowyo Mine (C- 1981 -019), I find the report in compliance with the following rules: 1. 4.09.1(11)(a) —The fill was inspected for stability by a registered engineer during the placement and compaction of fill materials. 2. 4.09.1(11)(b) —The qualified registered engineer provided to the Division a certified report within two weeks after the inspection that the fill is being constructed as specified in the design approved by the Division. The West Pit Fill was inspected on June 25, 2013 and the Second Quarter Fill Monitoring Report was received by the Division on July 9, 2013 The Second Quarter Fill Monitoring Report was received within the time frame as required by Rule 4.09.1. No appearances of instability, structural weakness, and other hazardous conditions were noted in the 2013 Second Quarter West Pit Fill Monitoring report. 3. 4.09.1(11)(c) — Rule 4.09(11)(c) is no longer applicable during this stage of fill construction. Activity on the West Pit Fill includes the operations of a fleet of scrappers regrading to achieve the approved post mining topography. The approved post mining topography is approved up to an elevation of 7460'. Currently, regrade work to the West Pit Fill has reduced the top of the fill to below an elevation of 7430'. Minor swell was noted in the Second Quarter West Pit Fill Monitoring Report at the 7250 West monument. The increase was documented at 0.203'. The displacement of the monument is minor and is not of concern in regard to the stability of the fill. The Second Quarter 2013 West Pit Fill Monitoring Report for Colowyo Mine meets all rules required by the Division. If you have any questions, feel free to contact me. Sincerely, Zach