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The cobbles and boulders in the lower layers of the alluvial <br />fans are almost entirely of hard, dense basalt which has <br />originated from the lava capping on Grand Mesa, with a few <br />sandstone clasts. The fragments range from angular to subrounded <br />and are generally unweathered with varying amounts of vesicles <br />(gas holes) in the basalts. The coarser fraction contains all <br />sizes of gravel, cobbles, and boulders but seems to consist <br />of a large amount of 6-inch to 36-inch rocks with some boulders <br />up to 10 feet across, <br />Thickness of the Alluvial Fans <br />The thicknesses of the alluvial fans over the Mesaverde Formation <br />bedrock could only be determined by a large number of test pits, <br />which would be an expensive operation. Due to the depths of <br />materials and the high percentage of cobbles and boulders, <br />equipment such as a large track-mounCed backhoe would be <br />necessary to explore the site. Three terrace levels occur on <br />the Fontanari property. However, in the absence of extensive <br />subsurface data, reasonable estimates of depth, and therefore <br />estimates of quantities, can be made. Depths used in this report <br />are based on observations in roadcuts, outcrops on canyon walls, <br />excavation at Quarry No. 2, and test pits along the Ute Water <br />Pipeline. <br />The thicknesses of the alluvium over bedrock along the Ute Water <br />Pipeline were found to be 12.5, 15, 19.5, and 21.5 feet in four <br />test pits excavated on May 6, 1999 (TP 1 to 4) at the north end <br />of the Fontanari property. The one test pit (TP 5) at the <br />southwest corner of the property was terminated at 16 feet <br />without reaching bedrock. Details of the materials encountered <br />are shown on the attached test pit logs. <br />Water Table <br />A high water table that would hinder mining of the gravelly <br />alluvial deposit under the Fontanari property is not expected <br />to occur, The site is a topographic high a minimum of about <br />120 feet higher in elevation than Rapid Creek and about 250 <br />feet higher than the nearby Colorado River. A small irrigation <br />ditch near the southwest corner of the Fontanari property carries <br />only small flows from Rapid Creek during spring runoff and would <br />not be creating a water table. Four of the five test pits <br />excavated by Ute Water on May 6, 1999 reached bedrock, and none <br />of the pits encountered a water table. <br />CONCLUSIONS <br />The necessary permits to quarry clay, silt, gravel, cobbles, <br />and boulders from the Fontanari property for commercial <br />production of riprap, roadfill, landscaping stone, and other <br />3 <br />