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suggested to clearly present this information in the permit. Consultation with the Division <br />is encouraged regarding this issue due to the considerable amount of experience that the <br />Division has regarding subsidence and monitoring plans at other underground mines in the <br />State. <br />Northfield Response: Structures and monitoring are listed for each structure. <br />DRMS response: Structures ate listed in Table 2.05.6-1 in and adjacent to the permit azea, <br />A city water tank is located north of the permit azea neaz the 35 degree monitoring zone. <br />Please also include the waterline(s) that serves this tank in Table 2.05.6-1 and annotate <br />same on the appropriate map. <br />37. For the residence located in the NE '/s of section 23, permit commitments regarding <br />potential subsidence control are found on page 2.05.6-19 and page 2.05.6-21. However, <br />these commitments seem somewhat vague regarding what the control measure(s) will be to <br />prevent subsidence from damaging the residence. Also, a 35 degree angle of draw "halo" <br />triggers some sort of evaluation of the mine plan and/or measures to be taken, yet that <br />"halo" is not shown on any map. Both the residence and the power lines to the north will <br />be subsided within the fast five year permit term. Please refer to questions #36 above when <br />considering your response to this issue. <br />Northfield Response: Mine plan changed to provide buffer zone. <br />DRMS response: Response accepted. <br />38. Pre-subsidence surveys (inspections) should be conducted for each structure and included <br />as an exhibit to the permit. In particular, documentation of the pre-subsidence condition of <br />the residence(s) andpower lines is ofparticular importance. <br />Northfield Response: Commitments to conduct surveys is now in permit text. <br />DRMS response: Response accepted. <br />38a. Sandstone cliffs outcrop upslope and adjacent to County Road 79 in or near the <br />proposed subsided area. It is not clear given the current permit application materials <br />where these cliffs fall within the underground panel layout and the proposed subsided <br />area. Please provide a map and/or orthophoto that depict the location of these cliffs <br />relative to the proposed underground workings. <br />Rule 2.10 Maas and Plans <br />39. Please ensure that all maps, plans, and cross-sections required by Rule 2.10 are to be <br />prepared by, or under the direction of, and certified by, a qualified registered professional <br />engineer or professional geologist. (Rule 2.10.3(2)) <br />Northfield Response: Maps have been prepared in accordance with Rule 2.10.3. <br />