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<br />' becember 1986 13 863-2052 <br />Up to 10 feet of colluvium (B-3) was encountered in the five <br />borings drilled as part of this investigation. As described in <br />the boring logs, such colluvium ranges in texture from silty clay <br />(CL) to silty gravel and cobbles (GM). <br />4.4 Surface Water <br />The steep northward-flowing draws which dissect the site are ero- <br />sion features resulting from surface runoff. The drainage areas <br />of these draws are limited by the ridge line that approximately <br />follows the southern property line of the tract, so they are <br />relatively small.. <br />No perennial streams cross the Little Middle Creek tract. The <br />South Fork of Foidel Creek, which crosses the northwest corner of <br />the tract, flows intermittently in the vicinity of the proposed <br />excess spoil structure. A buffer zone has been established <br />around Foidel Creek in which no mining or spoil disposal will <br />take place. The creek is therefore not expected to have any <br />influence on the excess spoil structure. <br />Streams in all other draws are believed to flow only intermit- <br />tently. All significant draws can be expected to flow contin- <br />uously during the period of peak snowmelt. However, maximum peak <br />flows will probably result from direct precipitation over the <br />drainage area during periods of intense thunderstorm activity. <br />The steepness which is characteristic of the sides of major draws <br />suggests that relatively high peak flows have occurred in the <br />past. <br />Once the box cut is developed, all surface runoff from upslope of <br />that point will drain into the box cut for subsequent removal, or <br />will be diverted around the box cut. This will effectively direct <br />Golder Associates <br />