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<br />needed, the riser section will be removed, leaving only the 30" <br />culvert under the road. The culvert is adequate to pass the flow <br />from a 100 year/24 hour peak flow with only minor detention time. <br />The embankment shows no signs of bulging, cracking, displacement, <br />or seepage, and only minor erosion at inlet locations. The primary <br />and emergency spillway structures are in good condition, with the <br />exception of a small hole approximately 1/4" in diameter, through <br />the principal spillway gate valve. Given the small size of the <br />hole, it would appear that the pond would provide sufficient <br />settling time for the design storm event. <br />The pond seldom contains water, and in fact monthly inspection <br />reports conducted over the past 3 year period indicate that there <br />was no standing water in the pond at the time that any of the <br />inspections were conducted. At the time of this inspection, the <br />pond was dry. The major portion of the pond bottom is heavily <br />vegetated by upland vegetation species, including rubber <br />rabbitbrush, snakeweed, various wheatgrasses and cheatgrass, <br />indicative of a somewhat more mesic site than adjacent areas, but <br />one that is not subject to frequent inundation. Although steep <br />slopes associated with the #1 Mine excess spoil fill and the #2 <br />Mine portal area backfill do not yet support a well developed <br />perennial vegetation cover, there is minimal evidence of erosion, <br />and no evidence of recent sediment deposition in the sediment pond. <br />The overall condition of the impoundment structure is good. <br />(iii) The extent to which existing impoundments or earthen <br />structures were constructed and certified in accordance with <br />prudent engineering designs approved in the permit. <br />The sediment pond was constructed in 1979, and a certified "as <br />built" plan view was provided by American Shield Coal Company <br />within an April, 1992 Reclamation Permit Application. The plan <br />view, designated "Exhibit 6", is dated November, 9, 1989, and is <br />certified by P.E., Greg Lewicki. A cross section through the <br />embankment showing the spillway structures and elevations, <br />designated "Exhibit 5", amended January 15, 1992, is also contained <br />within the application. Exhibit 5 was also prepared by Greg <br />Lewicki, but was not certified. The exhibits are on file within <br />the referenced application at the Division office in Grand <br />Junction, and at the Mesa County Courthouse, also in Grand <br />Junction. <br />(iv) The degree to which erosion and sediment control is present <br />and functioning. <br />a) All disturbed areas drain to the sediment pond, with the <br />exception of approximately 1/2 acre in the southeast corner of the <br />disturbed area, where a small sediment pond and two small topsoil <br />