Difficult Access Core Drilling
U.S. Route 20 is a major highway connecting the Willamette Valley to the central Oregon coast, and the section from Pioneer Mountain to Eddyville was the last remaining unimproved section between Newport and Corvallis. The project proposed to replace the existing highway with a new section that would be safer and 3 miles shorter. The Oregon Department of Transportation (ODOT) completed a preliminary design of the highway alignment and released the project for design-build.
Foundation Engineering Inc.
Yaquina River Constructors (a joint venture of Granite Construction Company Inc. and Wilder Construction)
Crux provided geotechnical exploration drilling services for Yaquina River Constructors, starting with the initial preliminary design for ODOT, and through the construction phase of work. A large portion of the new alignment was designed to be diverted away from the existing highway, through dense mountain forests. Access to the boring locations was along existing and abandoned logging roads.
Field operation work was completed over several seasons and primarily during the wet months. Access was severely impacted by rains, creating unsuitable conditions for conventional drilling equipment. Crux utilized a variety of methods to transport drill equipment, from a four-wheel-drive Unimog to medium-lift helicopter.
In addition to providing HQ3 coring in weak formations, Crux completed optical televiewer work utilizing Crux Oriented Borehole Logging (COBL) services. Instrumentation was compelted at several locations along the project alignment in order to measure slope movement and water elevation/pressure.