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commercial applications. The rocks and gravels are likely of varying composition. The probable components are intrusive and extrusive volcanic rocks, various fine-grained metamorphic rocks, sandstones and shales. The gray, silty overburden varies in depth over the Quaternary alluvium from 3 to 17 feet in the northwest portions of the proposed tract, from 7 to 12 feet in the central portion, and from three to 12 feet in the southeast portion. The river deposited alluvium varies in depth from 9 to 38 feet, averaging about 17 feet over the breadth of the project. The depth to the Mancos Shale is over 20 feet ' and ranges up to 42 feet, as indicated by drill holes. ' GROUNDWATER AND DRAINAGE The excavation of this proposed sight will reach below the water table, the depth of which was observed along the southeast side of the projectin a large drainage structure. The drainage easement is 50 feet wide; the drainage way is approximately 30 feet deep and shows a distinct zone of saturation approximately fifteen feet below the ground level. This indicates the water table level. With this type 'I of operation --- mining and excavation -=- a continuous de-watering system must be instituted and monitored when levels below the water table are met. ''I The proposed tract of land slopes gently in a westerly direction with runoff draining eventually into the Colorado River, which flows nearly parallel to the southwest property line. The one-hundred year flood ,i elevations (Flood Insurance Rate Map, Federal Emergency Management Agency) for the Railhead ' industrial Park vary from 4,517 feet at the northwest section of the tract, to 4,520 feet at the southeast corner. Based on elevations, the entire proposed tract should therefore situate anywhere from 1 to 10 feet above these elevations. UTILITIES AND OBSTRUCTIONS r z a ~r s Buried along, or below, Railroad Avenue are gas, water, sewer, and telephone lines. Railroad Avenue i is paved with curb and gutter for its entire length. A high pressure gas line extends from the northeast i ' to the west end of Railroad Avenue, then outward through a utility easement parallel to the far northwest boundary of this tract (Block Six). A barbed wire right-of-way fence runs along the northwest ~ I boundary of the utility easement. Interstate 70 has been elevated along this easement to pass over Highways 6 and 50 at the northwest corner of the Railhead Industrial Park. ~, 1 1 ~ I {~ ~ ~l 3 (~ ',