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measures were initially recommended, but upon re-inspection on 10/16-10/17/08, the <br />Division determined that the gully appeared to be stabilizing on its own. The Division <br />recommends that the location continue to be monitored, but has concluded that repair <br />measures are not warranted at present. <br />In summary, no areas of excessive erosion or instability of such an extent that would preclude Phase <br />II bond release are present within the release request area. Areas of minor erosion that may warrant <br />maintenance will be monitored during future inspections. <br />Topsoil Replacement Thickness <br />Within the SL-3 bond release area, all salvaged topsoil was replaced. Most topsoil replacement was <br />completed prior to 2000; road corridors were topsoiled in 2003. Soil replacement depth sampling has <br />been conducted and reported annually by SCC over the course of the permit life, and verification <br />sampling has also been periodically conducted by the Division. From 1980 to 1996 (e.g. roughly <br />corresponding to BRB-2 and BRB-3), approved average replacement thickness was generally 12" to <br />15", with apparently some limited exceptions allowing for average thickness as low as 9". From <br />1997 through 2003 (BRB-4), approved replacement thickness ranged from 3" to 10", averaging <br />approximately 6". Summary documentation was provided by SCC in Attachment D of the SL-3 <br />application, presenting the results of 933 sample holes over the entire 1793.5 acre area for which <br />Phase II bond release was initially requested. With the exception of a few outliers, soil thickness <br />ranged from 6" to 30", with an average thickness of 15.6". <br />Due to the extensive soil depth sampling previously conducted and reported, the Division did not <br />undertake additional soil depth checks during the inspection. There were no areas observed where <br />topsoil had obviously not been replaced, nor were there areas where soil or vegetative conditions <br />were indicative of deleterious materials in the root zone. A few very small and isolated locations <br />affected by saline seeps were observed, primarily in the vicinity of reclaimed highwalls. All <br />stockpiled topsoil within the SL-3 bond release area had been utilized for final reclamation, and the <br />stockpile locations had been properly reclaimed. <br />A summary of topsoil replacement documentation based on DRMS inspections, compiled from <br />Division files, is presented below: <br />• August 16, 1984 Inspection Report-Topsoil depths were checked in the areas where <br />topsoil was recently replaced adjacent to the 650 and 770 pits. Depths were also checked in <br />areas reclaimed during the past several years. The depths at all sample locations was <br />greater than 15 inches. <br />• May 30, 1985 Inspection Report-On the retopsoiled spoils of the Wadge area, topsoil <br />depths were checked and found to be in compliance with the terms of the permit. <br />• January 16, 1990 Internal Memo Topsoil thicknesses on reclaimed areas were extensively <br />sampled in 1988 and 1989. The summary memo for these sampling efforts is attached ...All <br />11