2007-03-06_GENERAL DOCUMENTS - C1994082

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that exceeds 3(h):1(v). This location is above Postmine Drainage Channel PM-10, on a hillside above apre-mine drainage. PM-10 replaced the pre-mining drainage. The original ground surface in this azea was steep. Backfill material was placed against undisturbed virgin ground at the top of the final highwall at this location. As previously discussed above in Section II and according to the PAP, slopes may exceed 3(h):1(v) in isolated areas above the final highwall where the natural slope is originally steeper than 3(h):1(v). Prior to this inspection the 2006 Rill and Gully Survey was reviewed and all areas identified on the survey were inspected during this and previous inspections. One feature is identified as a Settlement Crack located along the south facing north highwall. A large portion of the crack was successfully repaired prior to the Phase I inspection; however, farther to the east a separate section of the former highwall has cracked and settled. There appears to be about three feet of total displacement. Pictures of the settlement crack and offset are provided in the Inspection Photos Attachment at the end of this document (Photograph numbers 2 and 3). This location along the former north highwall will be excluded from the Phase I bond release, and should be hand repaired as opposed to using heavier equipment to avoid additional, unnecessary damage to the reclaimed highwall. Also, significant erosion is occurring along the old scraper road that is above the shrub plot and runs into the head of PM-13. A gully approximately 1 foot deep runs down the old road toward PM-13. A photograph of the unstable area above and to the west of PM-13 is shown in Photograph No. 4. This area is unstable and will be excluded from the Phase I bond release. Another significant erosion feature is a very long rilUgully located along the northwest side of the North Pit which runs for an estimated 2400 feet down to Armand Draw. This area of concern begins northwest of the shrub plot at the two-track road as a depressed area with sparse vegetation (probably a former access or haul road). As you walk to the northwest from this location the elevation drops and the rill deepens. Another rill joins this gully from the former haul road bench and the erosion extends down to Armand Draw. The gully is identified on the 2006 Rill and Gully Survey. The gully is not excessively deep but because of the length of the erosion and sparse vegetation in some sections of the gully this area is deemed erosionally unstable and will be excluded from the Phase I bond release. Photographs of this gully from its start down to Armand Draw aze shown in Photograph numbers 5 through 7. There were several additional areas identified during the Phase I inspection where erosion is occurring in the form of rills and gullies, but not to the extent that they will be excluded from the Phase I bond release. These locations will require maintenance, and should be monitored and hand repaired as described in the Phase I bond release inspection report dated October 18, 2006. One light-use road is located in the bond release request area and is shown on Exhibit 12-1, Operations Plan in the PAP. Light-use roads are discussed on pages 29 through 31 of Tab 13 in the PAP. Atypical light-use road cross-section is given on Figure 13-6 of the PAP. SCC has indicated to the Division (prior to the Phase I inspection) that they would like to retain the light-use road in the North Pit as permanent because it is needed for monitoring and the postmining land use. The lower portion of the light-use road is shown in Photograph No. 8. SCC has not speciFcally designated this road or any other roads at the Yoast Mine as permanent. SCC should request permanent retention of