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<br />Areas in the north half of the (112) permitted areas (west <br />of the pipeline right-of-way) will be excavated so that their <br />east, west, and south sides are "daylighted" to natural ground <br />with no remnant pit nor depression. A slope bank of 3- <br />horizontal to 1-vertical will remain as a headwall at the north <br />side of each excavated area. <br />Topsoil will be stripped from Excavation Areas E ~ F and <br />stockpiled around the perimeter to the east, west and south. <br />Initially sandstone will be ripped and dozed into a central <br />portion of Area E where a former pit operation has left an <br />unreclaimed pit. (See Figure 3)• <br />As the old pit is expanded to the south the product will <br />be dozed into the ever expanding portion of the worked-out pit, <br />to be hauled to various road project sites. <br />The following timetable shows the approximate expected <br />rate of excavation, although unforeseeable needs of the roads <br />department will dictate acceleration or retardation of the time <br />schedule. <br />AREA CGMMENCE OPS. COMPLETE OPS. <br />A Fall 1986 Winter 1986 <br />B Fall 1986 Spring 1987 <br />C Spring 1987 Summer 1987 <br />D Summer 1987 Fall 1987 <br />E Fall 1987 Spring 1988 <br />F Winter 1987 Summer 1988 <br />G Spring 1988 Fall 1988 <br />H Summer 1988 Winter 1988 <br />Material to be mined is an upper stratum of the Dakota <br />Sandstone formation that has been partially weathered, making it <br />weak enough to rip-lossen with a large single-tooth ripper <br />mounted on a large crawler tractor, Weathered depths vary from <br />three to seven feet depending upon recent geologic paramters of <br />weathering such as water penetration, freeze-thaw cycling, <br />overburden cover, etc. Below the weathered upper zone of the <br />Dakota sandstone are thick, massive beds of moderately to highly <br />cemented, hard, fine-grained, whitish-colored sandstone, which <br />normally defy all attempts at ripping. No excavation of the <br />firm unweathered sandstone will be attempted in the mining <br />operation. The following map shows the location of exploration <br />test pits dug with a wheeled backhoe. Depths of topsoil to the <br />surface of the weathered rock are shown within the hexagon at <br />each pit location. <br />-2- <br />