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Permit Revision Adequacy Comment Response <br />November 30, 2004 <br />Page 21 of 24 <br />110. On page 2.05-121 the application states that monitoring "should" be accomplished. The <br />Division requests that the wording be changed to "will be accomplished" and a time for the <br />activity defined (i.e. six months prior to mining within the angle of draw for a road section.) <br />The Monument Dam and Minnesota Reservoir should be surveyed prior to mining in the SOD <br />area and again before mining in panels north and panel E-9. Stock ponds could be surveyed <br />immediately before mining in the vicinity (possibly those within twice the angle-of--draw <br />distance.) <br />MCC Response: Exhibit 60B provides recommendations. <br />111. Exhibit 52, Water Augmentation Plan includes detailed and thorough calculations, <br />monitoring, and mitigation measures regarding water replacement in the event of impact due to <br />mining. The Exhibit clearly describes possible impacts to creeks from subsidence. However, <br />determination of the onset and magnitude of subsidence above Minnesota Reservoir is not part <br />of this plan. A subsidence monitoring plan is required above Minnesota Reservoir to determine <br />when and where subsidence has occurred, its magnitude, and a proposed frequency of <br />monitoring. Some sort of surveying will likely be necessary at a frequency commensurate with <br />the resource, in this case stream flow and quantity, to identify impacts as soon as they develop. <br />Although the minimum subsidence monitoring frequency is quarterly, more frequent <br />monitoring during undermining will be necessary to promptly identify potential impacts. <br />Please submit a detailed subsidence monitoring plan for the SOD, both above and below <br />Minnesota Reservoir. <br />MCC Response: Exhibit 60B provides recommendations. <br />2.06.8 Alluvial Valley Floors <br />112. Much of the alluvial valley floor reconnaissance information required by Rule 2.06.8(3)(b), and <br />upon which the Division's previous AVF determinations were based, was presented originally <br />on Map 66. This map is no longer included in the approved permit application document, and <br />was not included in the maps submitted as a part of the PR-10 application. The map has not <br />been updated for many years, and an updated reconnaissance investigation is warranted to <br />ensure that the status of agricultural activities as described for the alluvial deposits along the <br />various stream valleys in the life of mine permit and adjacent areas remains accurate. <br />Please provide a properly updated version of Map 66, with any additional maps as may be <br />necessary to comply with the requirements of 2.06.8(3)(a)(i), (ii), and (iii). Please provide in <br />addition, revised narrative as is warranted to reflect any changes in the nature or extent of flood <br />irrigated or sub-irrigated agricultural activities in the subject stream valleys, which may have <br />occurred subsequent to the original reconnaissance investigation. <br />MCC Response: MCC completed a natural resource survey, Exhibit 32B <br />r~ <br />