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7. The Sedcad designs for the small area exemptions at the north area, topsoil storage area <br />and the lay down area do not include sediment analyses to show that the 0.5 ml/1 settable <br />solids limit can be achieved. Please revise the Sedcad designs accordingly. <br />None of the Sedcad designs for the small area exemptions that use silt fence or straw <br />bales for sediment control shows the construction requirements, such as length, height <br />and tie back distance. Only the required surface area is given. Since the silt fence and <br />straw bales are part of a designed structure, please revise the Sedcad designs to show the <br />construction requirements for the silt fence and straw bales. <br />9. Please add a notation in the legend for Map 2.05-E 1-BCA2 that explains the use of <br />yellow color to designate small area exemption areas. <br />10. No entry road is designated on Map 2.05-E1-BCA2. Please explain how the fan site will <br />be accessed from the Bear Creek ranch road and whether or not a road culvert will be <br />needed. <br />11. Map 2.05-E1-BCA2 does not show how the lay down area will be accessed. Please <br />explain if a road will be needed and whether this road will require a road culvert in the <br />small drainage just north of the lay down area. <br />12. In comparing the existing topography shown on Map 2.05-E1-BCA1 with the proposed <br />post mining topography shown on Map 2.05-M6, it appears that there is an area just to <br />the north of the lay down area that will be disturbed. However, this area does not appear <br />to be designated as disturbed on Map 2.05-E1-BCA2. Please explain. <br />13. In the TR-60 Sedcad designs for the ditches and for the Bear Creek culvert, the horizontal <br />distances used in deriving the time of concentration values for each subwatershed appear <br />to be considerably longer than the hydrologic flow path length of their corresponding <br />subwatersheds. For instance, in the Sedcad runs for ditch BCCD-2 and the side postmine <br />channel, the total horizontal distance used for subwatershed area 1 amounts to 24,770 <br />feet, even though the drainage area amounts to only 53.1 acres and, referring to Map <br />2.05-E1-BCA2, the longest hydrologic flow path appears to be no more than 3,500 feet. <br />In another example, for the Bear Creek culvert, the horizontal distances given for <br />subwatershed area 1 add up to 41,383 feet. However, referring to Map 2.05-E1-BCA2 <br />again, the longest hydrologic flow path for the drainage area appears to be less than <br />30,000 feet in length. Please explain. <br />14. The summary sheet for the laydown area lists the disturbed area as being 0.13 acres in <br />size. The Sedcad design for the laydown area lists the area to be 0.4 acres. However, <br />referring to Map 2.05-E1-BCA2, the runoff area appears to be much larger since there is <br />no upland diversion ditch for the laydown area. Please explain or revise the Sedcad <br />designs and text for the laydown area accordingly. <br />2