Laserfiche WebLink
HazeltinelRoad Runners Rest IIIBrinkmann•WOOdward Gravel Pits Lining Project -Design Technical Memorandum <br />Denver Water <br />August 2003 <br />A review boundary is used where the correct boundary conditions can vary, such as where <br />seepage exits the slope. <br />The boundary conditions used for each seepage model are shown on Figures 4.2 through 4.7 <br />and summarized below: <br />1. No-flow boundaries across the vertical upstream boundary, the vertical downstream <br />boundary, and the bottom of the cross section. <br />2. Constant head boundaries through the alluvium at the regional groundwater elevation <br />upstream of the proposed cutoff wall equal to the depth in feet from the groundwater to <br />the top of bedrock in the section. The groundwater was considered to be 8 feet below <br />the ground surface in each section. <br />3. Two conditions for review boundaries were modeled: a) across the bottom of the <br />reservoir through the alluvium at the top of bedrock to the cutoff wall and b) across the <br />bottom of the reservoir and up the alluvium slope. <br />4.4 Hydraulic Conductivities <br />We assigned a hydraulic conductivity to each modeled bedrock layer in each cross section <br />based on 1) packer permeability tests conducted in the boring or borings located in the cross <br />section, 2) average hydraulic conductivities from other packer permeability tests performed on <br />bedrock with similar gradation, weathering, and fracturing characteristics, 3) published <br />correlations between hydraulic conductivity, soil classifications, and grain-size distributions, <br />and 4) geotechnical engineering judgment. <br />The hydraulic conductivities for each cross section used in our analyses are summarized in <br />Table 4.2. <br />GEI Consultants, Inc. 18 o?oso w-m-?~ u-uuae~r u.. ~~rm <br />