DESCRIPTION: Runway 12-30 and Taxiway A at the Columbia Gorge were reconstructed between 2012 and 2013. The work included pavement reconstruction and raising the southeast end of the runway up to 5 feet to meet FAA line‑of‑sight requirements.
SERVICE: Foundation Engineering completed a Phase I investigation to evaluate the existing pavement conditions and provide pavement design parameters and recommendations for subgrade preparation. Phase I also included infiltration testing to evaluate subgrade drainage. We completed a Phase II investigation two years later to evaluate potential borrow areas and assist with the preparation of the earthwork specifications to address the re-use of on-site materials. In addition, Foundation Engineering provided periodic consultation and construction observations. Geotechnical challenges included variable on‑site materials that consisted primarily of loess and shallow basalt.