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of the plan in the field to remedy the surface drainage and sediment accumulation problem <br />along the Taylor Draw access road. <br />Colowyo's Response: <br />Colowyo implemented erosion control measures (straw bales and riprap) in this area <br />during 2009. These measures lowered the velocity of runoff and improved road conditions <br />along Taylor Draw road and near Sump 5. Colowyo completed the installation of silt <br />fencing and wattles near the end of June, 2010. Additional efforts will be scheduled for <br />completion during the summer of 2010 to further mitigate flow velocity and sediment <br />transport. Flow directly to Sump S will be maintained by periodic maintenance with a <br />motor grader as needed to ensure direct flow to the sump in the future. Colowyo believes <br />this response provides the Division with a description of the efforts being undertaken to <br />manage this issue and a reasonable tinieframe to implement additional measures as <br />needed in the future. <br />12. Map 12 - Hydrology South Area shows the locations of the permanent post-mining <br />drainage channels. These channels are also shown on Map 41, as noted in question 10 <br />above. There are several discrepancies between these two maps. First, the channel <br />locations on the two maps do not match up exactly. For example, on Map 41 the Taylor <br />Ditch intercepts the Taylor Tributary Ditch at approximately station 30+00. On Map 12 it <br />intercepts at approximately station 35+00. Second, the North Tributary, East Pit Ditch is <br />not shown on Map 12. Please review the channels and their locations and intercept points <br />of all of the post-mining drainage channels shown on Map 12 and Map 41 and correct the <br />discrepancies. <br />Colowyo's Response: <br />Colowyo is in the process of generating a technical revision to address the issues <br />mentioned above. Updated maps, profiles and SEDCAD information will be provided. <br />The anticipated time frame for the submittal of this revision is late July/mid-August. <br />13. Colowyo is currently (starting in 2009) reclaiming the East Taylor watershed in the East <br />Pit. The East Taylor Pond is sized for a specific worst-case scenario for to recently <br />backfilled and graded surface area as well as surface area with new reclamation (0-1 year <br />growth, 1-2 year growth and 3+ year growth). Please review this worst-case scenario <br />contained in Exhibit 7ET to ensure that Colowyo does not exceed the worst-case <br />hydrologic model for the East Taylor Pond. Additionally, as Colowyo continues <br />reclamation in this watershed, please remember that all post-mining drainage channels <br />must be constructed and located as shown on Map 33, Map 41 and in Exhibit 7. <br />Colowyo's Response: <br />Prior to the 2010 reclamation season, Colowyo conferred with the Division to ensure that <br />additional reclamation activities in the East Taylor watershed would not exceed the worst- <br />case hydrologic model for East Taylor Pond. The Division and Colowyo agreed that the <br />reclamation completed in 2010 would not cause the pond to exceed its hydrological <br />modeling. Colowyo understands the Division's concerns and is implementing contour <br />furrows and surface roughing in this area to ensure that the area maintains its hydrologic <br />stability. Any discrepancies due to field fitting modifications will be reflected in the <br />updated materials provided to address the technical revision mentioned in Colowyo's <br />response to Item 12.