Subsurface Investigation Above the John Day River
Cornforth Consultants assisted Portland General Electric (PGE) with preliminary design for a wind-powered generation facility located in Sherman County, northeast of Wasco, Oregon. The preliminary plans for the overall project included a maximum generating capacity of approximately 338 MW from 225 wind turbine generator (WTG) units.
The first phase of development included 84 WTG sites, an operation/maintenance facility, miles of buried electrical collector cables, and a new power substation that links the WTG sites to the regional power grid. In addition to the power generation facilities, site development included miles of new unpaved roadways to access the WTG sites.
Cornforth Consultants’ work tasks included sixteen exploratory borings with eleven piezometer installations; eight exploratory test pits; office review of geologic and seismic hazard maps of the surrounding area; geophysical surveying; comprehensive laboratory testing; and completion of a data report with preliminary foundation design recommendations.