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presented in Permit Attachment 20.A "Pit Backfill Stability Report". The report <br />concludes that spoils material will exceed a Factor of Safety of 1.3 even under <br />saturated conditions with pit slope heights up to 200 feet and slopes of 2.SH:1V. <br />The Division has reviewed and accepted the report, as amended in response to <br />concerns identified during the PR-5 adequacy review. The report provides a <br />reasonable basis to conclude that the proposed final graded slopes in the South <br />Extension Area will comply with the stability requirements of Rule 4.14.2(1)(b). <br />The proposed operation is in compliance with the requirements of this section. <br />VIII. Revegetation <br />Information on baseline vegetation for the Seneca II-W Mine permit area can be found <br />in Tab 10. Section 10.1 contains the contents from the previously approved permit <br />application package and Section 10.2 contains the information from the 1997 <br />supplemental baseline study of the Seneca II-W South Extension area. Information on <br />the revegetation plan and revegetation success criteria for the permit area can be found <br />in Tab 22 of the permit application. <br />During the course of the original permit review, a number of concerns arose regarding <br />the control of reference areas and reference area comparability. The applicant proposed, <br />in meetings with the Division, an extended reference area concept, which was <br />subsequently approved. As approved, the applicant will utilize all undisturbed <br />vegetation communities (representing those to be disturbed by mining) within the permit <br />area as components of "extended reference areas". The components of the extended <br />reference areas will be represented by a minimum of 100 acres of undisturbed aspen <br />community, 300 acres of big sagebrush/grassland community, 450 acres of mixed brush <br />community, and 150 acres of western wheatgrass/alkali sagebrush community. In the II- <br />WSouth Extension area, the extended reference area wilt be represented by a minimum <br />of 230 acres of aspen forest, 300 acres of mountain brush, 150 acres of steep mountain <br />brush, 200 acres of sagebrush and 100 acres of wheatgrass/alkali sagebrush. <br />The permanent seedmixes are composed predominantly of native species, and the few <br />introduced species included are desirable and necessary to achieve the approved <br />postmining land use, and are not poisonous or noxious. Two years of monitoring data <br />for various reclaimed areas at the Seneca II mine which were seeded with the proposed <br />alfalfa variety Medica o falcata , at the proposed rate (.25 Ibs/acre) indicate that falcata <br />alfalfa does not compete excessively with other seeded species. Given its value as a <br />nitrogen fixer and as wildlife forage, inclusion of the species in the seedmix is <br />warranted. <br />In TR-32, SCC committed to notify the DMG each year with the seed mixes they can <br />obtain from the vendor. If the mix does not match the approved seed mix, SCC will <br />Seneca II-W Findings Document 56 June !2, 2006 <br />Permit Renewal No. 5 <br />