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Addressee Name <br />Date <br />Page 3 <br />3. The Note on Drawing 2.04 -M8 refers to Drawing 2.05 -M3 for supplemental detailed <br />vegetation information; however, Drawing 2.05 -M3 is the Elk Creek haul road profile. <br />Please reference the correct map for the supplemental detailed vegetation information. <br />4. Please update Drawing 2.04 -M8 Regional Vegetation sheets 1/2 and 2/2 to include the <br />latest permit boundary changes and include the vegetation types both within and beyond <br />the permit boundaries according to Rule 2.04.10(3). <br />5. Map 2.05 -M1 does not have the disturbance boundary labeled. Please update the map <br />and included the disturbance boundary. <br />6. Drawing 2.05 -M4 (4/4) shows a typical plan for drainage and sediment control of <br />degasification wells. Typically, a clean water diversion ditch is located upslope of the <br />pad to divert clean water away from the disturbance. The diversion ditch works well <br />when the slope of the hill is great enough to move the water. When the hill -slope is <br />shallow at wells located on top of the mountain, a diversion ditch may not be effective or <br />needed because the slope is too shallow to move water. At these shallow slope wells, the <br />diversion ditch causes a significant amount of damage to the surrounding vegetation with <br />little protection offered to the degasification pad. The Division suggests that a second <br />typical degasification well pad be submitted for review that accounts for shallow <br />hillslopes. Please include in the submittal a justification of maximum hillslopes for the <br />design and a diagram. A small area exemption must be provided for these typical pad <br />designs in compliance with Rule 4.05.2(3). <br />7. Drawing 2.05 -M4 (3/4) shows that Ditch D -6 flows on the west side of the Elk Creek Fan <br />to Ditch D -2 and ultimately to Elk Creek. Ditch D -6 also passes by the rock dust bins <br />which have a considerable amount of dust on the ground surrounding the bins. Due to <br />the proximity of the rock dust bins to Ditch D -6, the ditch has been diverted away from <br />Ditch D -2 to Ditch D -5 which drains to sediment Pond D. While the Division supports <br />this change it is unclear if Pond D has the capacity to support the extra runoff Please <br />submit revised maps and data showing that Pond D has the capacity to treat the additional <br />runoff of Ditch D -6 in accordance with Rule 4.05.6. <br />If you have any questions, please contact me at (303) 866 -3567 ext 8142. <br />Sincerely, <br />AW�A___Llv <br />Brock Bowles <br />Environmental Protection Specialist <br />