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• ~ 3) E.l"ISTL~G ROADS AS AFFECTED AREA The e.isting roads to be utilized as access routes for the permit mining activity are not to be substantially upgraded for this use. Surface use agreements negotiated with the land surface owner, BLM, and provided with *Exhibit S include only provision for normal maintenance grading and for replacing road base material to reo serve the existing condition of the road base and surface during permitted operations. The access route, including County Road 21, is not to be included in the bonded "ajjected area" of this permit. 4) ~IINLNG UNITS The enclosed *Exhibit C "}lining ~4ap" has been herewith modified to clarify the extent of all 16 indicated mining Units I through X1%/. The north- south width dimension of all Units (except Unit XVI, at 190') is designated as I50 feet. East-west length dimensions ho.+•ever vary from X00 to 1950 feet dependine upon the extent of the deposited gavel resource. 5) DRAL1'AGE CHANNEL RECONSTRUCTION The intermittent drainage channel that traverses mining Units IX through XIII shall be reconstructed at its approximate pre-mining location and outlet, featuring a 10-foot wide flat bottom ditch having 3-horizontal to 1-vertical re-vegetated sideslopes. Re-vegetation of the stream bottom is demonstrated by the existing situation to be impractical, and shall not be required nor attempted in the reclamation phase of the operations. The drainage channel slope run-down and 25 feet of the downstream channel at the west excavation boundary, however shall be rip-rapped to protect that portion of the channel from headwall erosion by the erosive forces of the higher velocity stream flow incurred by the steeper stream gradient. Rip rap material shall be provided from the lazger screened cobble from pit operations. The outflow from the replacement channel into the off-site natural channel shall be controlled by silt fence and straw bale filtration dike, to control particulate bed-load of the stream, as per the site's qualifying Stormwater Management Plan, until upslope disturbed areas have been successfully re-vegetated. Certification under the state-wide general Stormwater Permit shall be acquired, as required, before mining Unit IX. 6) DRAINAGE CONTROL BERA'iS Natural drainage for the majority of the entire site is practically non-existent due to the sparse precipitation, the absence of a significant upslope watershed, and the porous absorbing nature of the surface soils. Natural slopes are generally west to east, beginning with the first eight mining units sloping to the east- southeast, and the remainder of the units sloping to the east-northeast.