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CONCLUSIONS <br />• (1) Near-surface and subsoils generally consist of shallow, unconsoli- <br />dated sandy to silty clay with Intermittent sand and gravel layers <br />immediately overlying claystone bedrock. <br />(2) Tha depth to free water is relatively shallow, and seepage Into <br />excavations Is anticipated to be relatively slow through clay <br />Bolls end bedrock; however, no re difficult dewatering conditions <br />are anticipated at stockpile reclaim excavations where sand and <br />gravel soils of higher permeability exist. Subdraln systems may <br />be required at the truck dump and stockpile areas to Insure that <br />the phreatic surface is malntalned below final cut elevations. <br />The train loadout wilt also require drainage. <br />(3} Temporary vertical cuts in clay sobs and underlying bedrock <br />should remain stable for sufficient time to install bracing systems. <br />Permanent cut faces in the overburden soils with adequate drainage <br />precautions can be 1}:1 and in the claystone 1:1 (horizontal to <br />vertical). <br />(4) The most suitable foundations am straight-shaft piers drilled <br />into the bedrock, spread footing foundations bearing on bedrock, <br />and shallow spread footings placed on the upper natural soils with <br />precautions and details as given below. <br /> <br />SLOPE <br />This report presents the results of a Boll and foundation Investl- <br />gation for the proposed truck dump hopper, conveyor system, crusher <br />building, stockpile and reclaim, and t~aln loadout structures associated <br />with the Hayden Gulch coal processing facility. The site and geologic <br />conditions, subsoil conditions, depth to free water,•most suitable types <br />of foundations, bearing pressures, together with other design and construc- <br />tion details, are discussed. <br />An addendum to this raport.ls being prepared to cover changes in <br />location of the truck dump, crusher and percolation test results. A <br />separate report Is also being prepared on the railroad spur,% <br /> <br /> <br />) <br />i <br />.~ .,..i+ <br />