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Exhibit D CMLRB 1!2 Permit Application Agile Slone Systems. Ina. • gravel buffer. The road will be on the inner portion of the buffer and not be on the portion of the gravel baz sloping into the creek. The road will be swaled or ditched to drain into the pit and plant areas. The buffer north of the plant will have a l:l slope from the plant level at 5,800' to the 5,810' to 5,815' buffer top level. The buffer will have 2 cuts to the 2 crossings. The sandstone quarry road will drop through the buffer from about a 5,815' height to 5,805', tum about 90 degrees north and then drop another 10' to the approximate bridge level of 5,795'. The granite crossing road from the plant area will simply follow the natural slope from the plant floor at 5,800' to the crossing level at 5,780'. While '/z of the buffer will not be used as a road, it is included as affected land acreage as a precaution. The crossings to the sandstone and granite quarries, maintenance/office/locker room building, parking lot, fuel tank, railroad loop track, railroad wyes, railroad stub tracks, truck scale and roads as designated will either be built. Some existing roads will be upgraded. The quarry track will be built when deemed appropriate by the applicant. The quarry plant area will be started to construct sediment ponds and stormwater berms. Development benches will be started at the quarry to both develop the quarry and expand the quarry plant area. 1.4 Geology The mine plan involves 3 geologic terrains: sand & gravel, granite and sandstone. See • geologic map. SAND & GRAVEL Bedrock units of Jurassic and Cretaceous age subcrop beneath the sand & gravel deposit. In stratigraphically ascending order these units include the Morrison Formation, the Dakota Group (Purgatoire Formation, Dakota Sandstone), the Colorado Group (Graneros Shale, Greenhom Limestone, Carlisle Formations) and the Niobrara Formation. Structurally, the bedrock units were deformed during the Laramide Orogeny into a syncline whose axis trends generally NW-SE and passes beneath the project area. During the Larmide, the region and project azea were also cut by several faults as shown on the USGS geologic map. The gravel to be mined is a Quaternary Arkansas River fine to medium grained sand to very coarse cobble including boulders up to several feet in diameter. The deposit is over 1,200' wide, 2,500' long and several to +60' deep. The gravel deposit rests on steeply dipping Mesozoic sediments including sandstones, shales, and limestones of the Dakota Group and Greenhorn, Carlisle and Niobrara Formations. The Graneros Shale and Pierre Shale may also underlie the river gravel. The river gravel is one of five distinct terraces formed above the present Arkansas River level(Powers, 1935). The sands and gravels are primarily arkosic and siliceous rich materials derived from the upper Arkansas River Precambrian granites and granite gneiss. A number of test pits where dug in July 1997, demonstrating a well sorted, relatively coazse gravel deposit containing low amounts of • minus 100 mesh materials. No potentially acid forming mineralogy of sufficient amounts 5