Terraphase Engineering Wins Contract to Provide Environmental and Geotechnical Engineering Services for the Presidio Parkway Project, San Francisco, California

The Presidio Parkway Project is underway with the replacement of Doyle Drive (Route 101), the southern access road to the Golden Gate Bridge. As part of the construction team led by Flatiron/Kiewit Joint Venture, Terraphase will provide environmental and geotechnical engineering services to the Public Private Partnership (P3) responsible for the design and construction of the parkway. Terraphase will be working with the Presidio Trust, Caltrans, and Flatiron/Kiewit JV to characterize and manage soils in the project area. As part of the construction activities, Terraphase will manage soil disposal, conduct groundwater treatment system monitoring and reporting, and provide on-call environmental services. In addition, Terraphase is evaluating the spoils generated during the cement deep soil mixing (CDSM) process, used to provide subsurface stability, for beneficial reuse on the project, potentially significantly reducing disposal costs and minimizing air emissions that would be incurred with CDSM spoil disposal and clean fill importation.

The Presidio Parkway (scheduled for completion in 2015) will be the regional gateway through the Presidio and Golden Gate National Recreational Area. The P3 includes Golden Link Partners (developer), Flatiron/Kiewit JV (contractor), the California Department of Transportation, San Francisco County Transportation Authority, Presidio Trust, National Park Service, California Department of Veterans Affairs, the Golden Gate Bridge Highway Transportation District, the Metropolitan Transportation Commission, and the Federal Highway Administration.