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Subsidence Evaluation for the <br />Exhibit 60E Southern Panels, Apache Rocks West & Sunset Trail Mining Areas Page 32 <br />general areas listed below (listed in an east -to -west, north -to -south direction) have a low to high <br />rockfall potential (Map 1): <br />1. Steep slopes (with an estimated rockfall potential ranging from moderate to high) located <br />north of Dry Fork and west of Minnesota Reservoir. However, no mining is planned in <br />this area, so this rockfall area would not be impacted. <br />2. Two steep ridges with cliffs and ledges, located above the northern part of longwall panel <br />E9 east of the landslide area described in Section 10.1 (mostly in the SE'/4 of Section 32, <br />Township 13 South, Range 90 West). There are no roads or man-made structures in the <br />area. <br />3. The south end of a steep ridge containing cliffs and ledges located north of Minnesota <br />Reservoir and Dry Fork and north of the confluence of Deer Creek and Dry Fork above the <br />western edge (within the area of mining influence) of longwall panels E1 and E2 (S1/2, <br />Section 29 and the NW'/4 of Section 33, Township 13 South, Range 90 West). The Dry <br />Fork road is located 400 to 500 feet south of the nearest area boundary. Following mining <br />in these longwall panels, no additional rockfall was observed during semi-annual field <br />studies. <br />4. A steep to moderately steep slope containing eight separate rockfall areas, located north <br />and south of Dry Fork and its tributaries. The estimated rockfall potential is low to <br />moderate. The rockfall areas are located above longwall panels E1 to E4 (Sections 33 and <br />34 and the NE% of Section 35, Township 13 South, Range 90 West). Following mining in <br />these longwall panels, no additional rockfall was observed during semi-annual field <br />studies. <br />5. The area is located in the southwestern part of the South of Divide mining area east of the <br />main fork of Minnesota Creek. While the majority of this area is located outside the <br />influence of mining, the northeastern part of this area, which has an estimated moderate to <br />high rockfall potential, is within the area of mining influence of the western and southern <br />part of longwall panels E8 and E9, respectively (located mostly in the W%2 and S%, Section <br />5, Township 14 South, Range 90 West). <br />6. This area contains six rockfall areas that have locally steep ridges. The area is located near <br />the headwaters of Deer Creek, Poison Creek, Lick Creek, and a tributary of Dry Fork. The <br />areas, which have an estimated low to moderate rockfall potential, are located above, or <br />partly within, the area of mining influence of longwall panels E5 to E8 (located in parts of <br />Sections 3, 4, 9, and 10, Township 14 South, Range 90 West). <br />7. This area contains three rockfall areas that have an estimated low to high rockfall potential. <br />It is located in the Lick Creek area south of any currently planned mining (located in parts <br />of Sections 8, 9, and 16, Township 14 South, Range 90 West). <br />8. This area is located on the east side of the main Deep Creek channel above longwall panel <br />E3. This area is identified as having low to moderate rockfall potential. It is located in an <br />831-032.816 Wright Water Engineers, Inc. <br />October 2018 <br />