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New Horizon Mine TR-57 <br />2nd Adequacy Review <br />21-Oct-2008 <br />Page 9 of 15 <br />indicates replacement of 18" Lift A and 27" Lift B. Please clarify this apparent <br />discrepancy and amend the map and/or text as appropriate. <br />Item Resolved <br />21. We have questions regarding the soil stripping process that was employed prior to <br />February 2008, in the 1999 expansion area west of 2700 road, as described at the top <br />of page (d)-17. Narrative indicates that soil was stripped in one mixed lift of <br />approximately 18" to 24", followed by stripping of suitable subsoil of an approximate <br />depth of 24 inches. This subsoil material was then placed on the surface of the <br />graded spoil immediately west of 2700 Road, according the narrative. Our <br />understanding based on discussion and review of photos presented at the February 15 <br />meeting in Grand Junction, was that in recent years, the practice has been to strip <br />topsoil down to the top of the calcic horizon (essentially corresponding to "Lift A"), <br />with no subsequent stripping of subsoil or near surface overburden for replacement on <br />the graded spoil surface prior to topsoiling. Rather, the topsoil stripped was replaced <br />directly on graded spoils. Please clarify this point, and revise the narrative if <br />warranted. <br />Item Resolved <br />22. The second paragraph on page (d)-17 is confusing with respect to Lift B stripping <br />thickness, and is the same or very similar to narrative in Section 2.04.9. Please see <br />Comment 10b above, and revise the narrative accordingly. <br />Item Resolved <br />23. The third paragraph on page (d)-17 includes a description of the horizons designated <br />to comprise topsoil Lift B. The description differs somewhat from Lift B as <br />described on page 2.04.9-19. On page 2.04.9-19, Lift B includes Horizons AC, Bw, <br />and Bt (if pH of the horizons is greater than 8.0), as well as Horizons Bk, Btk, and C, <br />with no pH limitation indicated for the latter three horizons. Page (d)-17 narrative <br />indicates that the latter three horizons would only be included if the pH is less than <br />8.0. The Page (d)-17 version would appear to be erroneous. Please amend as <br />appropriate. <br />Item Resolved <br />24. See comment 13d, above, regarding non-prime farmland soil salvage, and amend the <br />next to last paragraph on page 2.05.4(2) (d)-4 to be consistent with revisions made in <br />response to 13d. Apparently, the plan is to salvage a single topsoil lift in the non- <br />prime farmland areas, with separate salvage of a Bench 1 overburden lift for <br />replacement as "suitable subsoil". Please clarify how the bottom of the topsoil lift <br />will be defined for field salvage operations. <br />In this item, the Division requested the operator to amend narrative in Section <br />2.05.4(2)(d), regarding non-prime farmland soil salvage, to be consistent with <br />narrative on the same topic in Section 2.04.9, and to clarify how the bottom of <br />the mixed lift topsoil salvage layer would be defined for field salvage operations. <br />9