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111. COMMENTS -COMPLIANCE <br />Below are comments on the inspection. The comments inciude discussion of observations made <br />during the inspection. Comments also describe any enforcement actions taken during the inspection <br />and the facts or evidence supporting the enforcement action. <br />1 Disturbed area runoff appeazed to have been effectively contained within the disturbed area, however <br />some berm build-up was noted to be warranted within the immediate vicinity of the guazd shack. <br />North Portal Area and Coal Canyon <br />~ Pond 13 contained a few shallow puddles. Some rilling was noted on the pond inslope. The slope is to <br />be roughened, seeded and mulched in association with site revegetation later this fall. <br />{ Extension of the topsoil pile collection ditch at the northwest corner of the North Portal Area across <br />the comer of the regraded area to the Pond 13 collection berm appears to be warranted. <br />SAE-I Sediment Trap, Sediment Pond 6, Sediment Pond 10, and Sediment Pond 11 were all dry or <br />neazly so. <br />{ At the upper dip section on Coal Canyon, one of the center culverts was partially blocked with woody <br />debris and sediment and should be cleaned out. The metal railing still needs to be removed, and <br />operator indicates this work has been scheduled. <br />{ Within the permanent diversion segment between the upper dip section and the large double culverts, <br />storm flow appeazed to have spread across the channel 1 to 2 feet deep, with intermittent minor <br />entrenchment, particulazly along the base of the riprap at the upper end and at outside bends of the <br />channel. <br />{ Below the double culverts in the channel segment adjacent to the North Portal reclamation area, there <br />is significant channel entrenchment at the lower end of the segment, where the dip section concrete <br />structure was removed in association with reclamation of Haul Road 2. The down-cutting in the <br />channel is associated with a relatively abrupt increase in channel gradient at the lower end of the <br />segment. Approximate measurements of the channel profile made with an abney level, stakes, and <br />pacing indicated the following: 675 foot segment from double culvert outlet downstream had minimal <br />channel erosion, relatively uniform gradient of approximately 2%. Approximate 300 foot segment <br />from vicinity of upper end of former concrete structure to Pond 13 riprap spillway outlet had a <br />gradient of 4% to 5%, with significant downcutting. Downstream from the spillway outlet, channel <br />slope is approximately 1-2%. It would appear that sediment likely accumulated in the upper segment <br />of the channel during mine operations, as a result of the partial obstmction created by the concrete <br />channel crossing. Removal of the stmcture has left the abrupt slope transition, or knick point, that will <br />be incised during flow events. The Division is evaluating the significance of this feature, and the <br />possible need for corrective measures. Map Exhibit 8C (Roadside North Portal Post Mining <br />Topography) depicts channel gradient ranging from approximately 1.8% at the upper end of the <br />segment, to approximately 2.8% at the lower end. <br />2 West Portals and South Fan Areas <br />1 Benn and silt fence sediment control swctures were generally in good condition. At the small soil <br />borrow azea near the South Fan, the berm had been entirely replaced by silt fence as requested. One <br />segment of silt fence located on the reclaimed road to the South Fan is in need of repair. <br />