C153514 Feasibility Study - Laserfiche WebLink

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I I I I I I I I I I I I I I I I I I I The boreholes were advanced through the embankment soils using air rotary techniques occasionally supplemented with a water mist and/or foam drilling fluid. Representative soil samples were obtained within the embankment using either a standard penetration test split spoon sampler or an Acker type spoon sampler equipped with segmented brass liner rings. The number of blows of a 140 lb hammer dropping 30 inches required to advance the sampler 12 inches was recorded during each sampling run as an indicator of the material's consistency. Following sampler retrieval and visual classification of the soils, each sample was packaged in plastic bags for transport to SRK's soils laboratory in Lakewood, Colorado. The boreholes were advanced through the foundation bedrock using HQ wire1ine coring techniques. The core barrel was advanced a maximum of 10 ft for each coring run. Following retrieval of the core barrel, the rock core sample was visually classified and logged in detail. Percent recovery, Rock Quality Designation (RQD), and fracture orientation, spacing and condition were noted for each core. Each core was then packaged in a core box for transport to SRK's laboratory. Following completion and flushing of each borehole, pressurized inflow permeability tests were conducted in the portion of each borehole below the bedrock surface. A pair of pneumatic packers set five ft apart were used to isolate consecutive five ft borehole segments. The packer permeability tests were generally conducted using a single pressure setting and clean water as the injection liquid. Injection pressures were generally maintained at or below the maximum allowable using the commonly accepted criterion of one psi per foot of overburden material above the section being tested. The test results -7-