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<br />Additionally, at the discretion of the operator, if during the course of operations it <br />appears as though it would be more practical to route runoff on the northern part of the <br />affected area to a closer impoundment, an additional secondary structure will be <br />created on the east side of the Phase 2/Phase 3 boundary. The secondary impound- <br />ment would remain until such time as as reclamation occurs. <br />Overburden located immediately upstream will be excavated to forma non- <br />jurisdictional impoundment across the head of an existing gully. The height of the <br />berm will be less than 10 feet, be 10 to 12 feet wide at the crest, and have a minimum <br />outslope and inslope of 2:1 (h:v). An emergency spillway will be created where one <br />side of the crest of the embankment intersects the native vegetated ground surface. <br />The invert of the spillway will be about two feet below the crest of the fill. The <br />embankment will be seeded with a perennial sod-forming species, such as western <br />wheatgrass, to minimize erosion. <br />The depth of water allowed to accumulate in the impoundment will about three <br />feet and will tie regulated by a 10-inch pipe (SDR-35 or equivalent) placed through the <br />embankment. A trash screen will be constructed over the pipe's inlet to prevent <br />clogging. The pipe will outfall just beyond the toe of the structure where a rip rap <br />apron, underlain by a filter fabric (Mirafi 140N or equivalent), will be established to <br />resist erosion. A minimum of three feet of freeboard will occur between the inlet of the <br />pipe and the spillway to provide additional volume (and detention) for settling if <br />needed. <br />Storm Water Permit <br />The Colorado Department of Health, Water Quality Control Division, will be <br />contacted to determine whether a storm water permit will be required. If so, a storm <br />water permit application will be submitted. <br />-14- <br />