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Page 7 <br />stability of pillars is described as pillars having a factor of safety of 1.5 in Section 1.9 of Exhibit <br />15 (page 28). A note on Map No. 27A is that "Mining that would cause subsidence is not <br />permitted under the limited extraction zone." <br />A limited extraction zone is proposed under Hubbard Creek and the Hubbard Creek entries (See <br />Exhibit 16) and Map 27. I recommend that the Hubbard Creek Road be shown on Map 27. It <br />needs to be, and likely is, in a limited extraction zone. <br />Rule 2.05.6(6)(b)(iii) If the description of worst possible subsidence consequences, prepared in <br />accordance with Section 2.05.6(6)(b)(i), determines that material damage or diminution of <br />reasonably foreseeable use could result in the event of mine subsidence within the permit and <br />adjacent areas, the application shall include additional information as required by either one of <br />the following: (A) A subsidence survey, as described in Section 2.05.6(6)(e); or (B) A subsidence <br />control plan, as described in Section 2.05.6(6)(f). <br />Option B has been selected for other structures and renewable resource lands. <br />Rule 2.05.6(6)(c) Subsidence Monitoring Program. <br />The description of the monitoring program begins on page 2.05-115 of the PAP. Extensive <br />monitoring is accomplished, and reports are filed with the Division. However, there are some <br />gaps and missing elements in the program. <br />Rule 2.05.6(6)(c)(i) The monitoring program shall be designed to determine the commencement <br />and magnitude of subsidence movements which occur and shall include the following monitoring <br />techniques: <br />A reference to a seismic monitoring program, Volume IIIA, Exhibit 18, is made on page 2.05- <br />C 117. However, this exhibit is incomplete for such purposes. The Exhibit describes the array and <br />stations, but does not prescribe timing (start, duration, termination) and reporting (what). <br />Rule 2.05.6(6)(c)(i)(A) Monuments shall be installed and surveyed prior to the commencement of <br />mining. <br />This is a performance specification. Timing could, however (and I recommend it be), be outlined <br />in the PAP as part of the description of the monitoring plan. <br />Rule 2.05.6(6)(c)(i)(B) Monuments shall be situated to appropriately monitor ground surface <br />movement, vertical and horizontal, within the area proposed to be undermined, including an <br />area to accommodate the predicted angle-of-draw. <br />The location of these monuments should be identified in the monitoring program, and have <br />-7F the concurrence of the Division. There is a difference between the layout of the B seam