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,.. into the lower pit for the past number of decades has decidedly helped to <br />minimize any serious channel formation from the higher elevations of the . <br />disturbed azea to Taylor Gulch. The fina160 feet of drop at the southern end of <br />. the highwall configuration into the lower pit area is bound to carry an elevated <br />amount of sediment due to increased velocity of the run-off. Directing the flow <br />into the lower pit will help to mitigate sediment loading prior to return of the <br />water to the watershed below. The bedrock conditions of permeability and high <br />infiltration have shown that water does not back up in the lower pit and quickly <br />returns to the watershed below without the sediment load. In addition, creating a <br />clean water diversion channel directly to Taylor Gulch would entail a culvert <br />crossing the FS Road 228 and additional structures to transport the flow down <br />gradient in a series of sediment control drop structures. These sediment control <br />structures aze problematic at best and un-necessary given the existing conditions <br />in affect. <br />24. Individual highwall bench ditches will be constructed on the outer one third area <br />of each beach with similaz `~" shaped configuration, albeit more shallow than the <br />upper west ditch. The ditch will be constructed a minimum of 8' from the bench <br />top edge to allow room for a low berm to keep ditch flow in a southemly direction <br />and minimize any tendency for ditch flow to find a path over the bench top. The <br />ditch will be cut via bulldozer into soils used for re-vegetation app. 1' deep and up <br />to 4' wide with steep walled gradient to outsiope side, app. 2:1 on outslope side <br />and app. 4:1 on highwaLl side of ditcb_ The ditches will be located near the center <br />to outer portion of the bench top to minimize any blocking of ditch flow due to <br />sloughing or rock fall from the bench cut over time. Flows in any one ditch is <br />expected to be no more tban a few gpm unless severe storm event is underway. <br />25. Mine phases identified on page 11 of the narrative will be located on the Mine <br />Plan Map Cc. <br />26. The one acre azea within the 3.17 acre mill site claim will be outlined on the <br />amended affected land map Ca. <br />27. The operator has reseazched all property owners within 200' of FS Road 228 and <br />is sending notice to each of the 12 landowners identified on the Affected Land <br />Map included in this mailing. Certified mail receipts will be forwarded to the <br />Division. <br />28. As described on pages 4 and 5 of the narrative, the marble bed measures a total of <br />170 feet in thickness in the vicinity of the active mining zone including the white <br />marble and gray marble seams lying on either side of the white mazble bed. The <br />volume of overburden and waste rock to be mined will vary according to the <br />maximum depth of mining, which is yet to be determined by rock hardness, <br />weathering characteristics determination, and rock competency evaluation as the <br />highwall bench development progression exposes bedrock currently lying behind <br />and west of the marble ore body. The gray marble contacts on either side of the <br /> <br /> <br />