Project Description

The project site is located within the Weyerhaeuser Vail Tree Farm near Vail, Washington in Lewis and Thurston Counties, Washington. This project included the construction of 38 Siemens SWT 120 wind turbines, one substation, miles of roads, and electrical collector and transmission lines. The turbine string will be oriented primarily along a ridge top in a generally southeast to northwest alignment in the southern portion of the property in Lewis County. Roadways were constructed for access to the turbine locations in both Lewis and Thurston Counties. A crane pad was graded at each turbine location to set the tower. This project is in response to increasing demands for electricity and the requirement under Washington state law that utilities meet a defined portion of their customer demand from clean, renewable sources of energy. The project is expected to be fully operational by the end of 2018.

Scope of Work

Included completion of geotechnical borings to determine soil and groundwater conditions at the site. The purpose of this geotechnical report is to provide information regarding subsurface conditions. The findings are presented to aid RES and the design team to develop design recommendations. In general, our scope of work was as follows: At least 72 hours prior to exploration, RGI contacted One-Call to locate known public underground utilities. Mobilized one track-mounted drill rig and water truck with crews and associated equipment to the site. Drilled exploratory borings at 37 turbine sites. Drilled six exploratory borings in the existing roadway to a maximum depth of 25 feet. Excavated a test pit at T19 that was not accessible to the track rig. Developed descriptions of the on-site soil and bedrock in accordance with USCS and ASTM standards and record information on the boring logs. Collected samples of subsurface materials for laboratory testing. Soil samples were then labeled and sealed in moisture-proof containers. Bedrock cores were placed in core boxes and photographed. Prepared a draft and final report.