Drilled Shafts UPRR Prebore Shafts / Harrisburg, OR Predrilling 12 shafts through hard rock boulders for the installation of drivin piles. West Slope Reservoir U of P – Shiley Hall Related Case Studies Block 35 John RossI-205 Columbia & Willamette River…Portland Aerial TramI-84 at the DallesNE Hwy 99 – NE…WB Passing Lane – US…Bear Creek BridgeInfluent Pump StationTacoma Second Supply PipelineCalpine-McNary Transmission Line