Drilled Shafts I-84 at the Dalles / Dalles, OR Installed 24 drilled shafts for a bridge replacement. Shafts were 42″ diameter infill over basalt. Utilized a down the hole hammer to significantly reduce drilling duration. Lift Station 10B Columbia Center Blvd Related Case Studies UPRR Prebore ShaftsBlock 35 John RossI-205 Columbia & Willamette River…Portland Aerial TramNE Hwy 99 – NE…WB Passing Lane – US…Bear Creek BridgeInfluent Pump StationTacoma Second Supply PipelineCalpine-McNary Transmission Line