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2. Provide the Division with an as-built certification by a registered, professional <br />engineer for the ditch segments noted to document they have been repaired and <br />completed as designed. <br />3. Repair the leaking outfall on the West Taylor Pond and provide the Division with a <br />report detailing the problem and the repairs completed. <br />On 18 August 2010, at approximately 8:30 am, Kent Gorham and I inspected the <br />Prospect watershed area of the East Pit at the Colowyo Mine. There have been numerous <br />permitting actions regarding the Prospect watershed over the past few years and the area <br />remains a concern for the Division. There have also been numerous internal discussions <br />regarding the post-mining drainage channels constructed during the 2009 reclamation <br />season and whether they were built as designed, which is why Kent accompanied me on <br />the inspection. <br />The problem with the North Tributary, East Pit ditch is that the ditch was not constructed <br />in the approved location, the ditch was not constructed based on the approved designs (as <br />it relates to ditch width and depth) and the ditch did not have correct size of riprap. The <br />problem with the Final East Pit ditch is that the ditch was not constructed based on the <br />approved designs (as it relates to ditch width and depth) and the ditch did not have correct <br />size of riprap. The problem with the Taylor Tributary Ditch is that the ditch was not <br />constructed based on the approved designs (as it relates to ditch width and depth) and the <br />ditch did not have correct size of riprap. Colowyo will need to reconstruct all of these <br />ditches and install the correct size of riprap. <br />The problem with the West Taylor Pond, which was inspected later in the day on 18 <br />August 2010, is that there is a leak somewhere below the water level, on the primary <br />discharge pipe, that is allowing water to discharge from the pond from a point that is not <br />permitted (the water level was about four feet below the weep hole, which is an approved <br />passive discharge point). The discharge was from a leak in the primary riser, which <br />could be heard trickling in the riser pipe. The pond embankment remains stable and there <br />is no seeping from the embankment. Colowyo will need to open the gated discharge <br />valve on the riser pipe and determine where the leak is coming from and fix the leak. <br />More detailed information regarding these NOV issues can be found in the Division's 18 <br />August 2010 inspection report and the "Request to Vacate Package" submitted by <br />Colowyo. <br />Based on the above information, the Division believes that Colowyo is in violation of the <br />following Rules: <br />Rule 4.05.3(7) "Diversion design shall incorporate the following: (a) Channel linings, <br />including channel riprap, shall be designed using standard engineering practices to pass <br />safely the design velocities. (b) Freeboard shall be no less than 0.3 feet. Protection shall <br />be provided for transition of flows and for critical areas such as swales and curves. <br />Where the area protected is a critical area as determined by the Division, the design <br />freeboard may be increased."