2023-01-05_REVISION - C1981019 (13)

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placement of topsoil. Final slopes, in general, do not exceed one vertical to three horizontal (lv:3h). Beginning in 1983, surveys were conducted to assure attainment of approximate original contour. Survey results were submitted on a yearly basis as part of Colowyo's Annual Reclamation Report. In 1987, this requirement was reduced to require survey reports only every two and onehalf years. In 1992, swell factor monitoring and analyses were terminated (PAP Volume I, Section 4.14.2). In the South Taylor Pit, with the exception of the two valley fills, Colowyo will return all mined lands to approximate original contour, with reclaimed surfaces resembling the general surface configuration of the area (though changes will occur on a smaller scale). The Division has, however, granted a variance from AOC for the steep slopes at the edges of the South Taylor Pit. These steep-slopes will be graded to a more gently-sloping topography, which will enhance the post-mining land uses of rangeland and wildlife habitat. These lands are owned by the Colowyo Land Management Company and the BLM. Both Colowyo and the BLM have provided letters approving of the post-mining topography and the change in AOC, located in figure 2.064-1 of the PAP. Maps 18A and 19B of the PAP show the pre-mining topography and post-mining topography of the South Taylor Pit, respectively. Drainages in the South Taylor Pit are constructed with gradients similar to those originally present, and complement the drainage pattern of the surrounding terrain. Premining and postmining drainage profiles are found on Map 33B of the PAP. Final grading plans for the South Taylor Pit provide a surface that both minimizes erosion and slippage following the placement of topsoil. Final slopes, in general, do not exceed one vertical to three horizontal (lv:3h). The Collom area to be mined will be restored to a topography approximating pre-mining grades. The slopes of backfilled areas, as necessary, will utilize contour furrows for erosion control and stability. Final grading plans for the Collom pit will be conducted in a manner that minimizes erosion and provides a surface for topsoil that minimizes slippage. Final grading will be accomplished so that overall grades will not exceed lv:3h. Backfill and grading for the Collom Pit is shown on Maps 19C and 29B of the PAP. D. Specific Findings Required by Section 4.14 The following specific findings are applicable to all areas of the Mine including the East Pit, West Pit, Section 16 Pit, South Taylor Pit and Collom Pit. 1. The Division approved the retention of box cut spoil or initial cut spoil outside the pit area since Colowyo has demonstrated that such material is not required to achieve approximate original contour in accordance with Rule 4.09.1 (Rule 4.14.1(2)(d)). Proposed Decision and Findings of Compliance January 5,2023 Permit Renewal No. 8 Page 150