Historic Skykomish School


To meet the needs of a nationwide transportation client, Farallon researched and implemented a unique and complex thermal remediation system.  The remediation system includes hot water flushing to facilitate nonaqueous-phase liquid recovery, soil vapor extraction to recover volatile organic compounds, and a sheet pile barrier for hydraulic containment.

A client’s former maintenance and fueling operations resulted in petroleum hydrocarbon contamination beneath a historical school.  Farallon researched and evaluated various design alternatives and, after comparing the relative performance of each cleanup alternative against school-specific criteria, Farallon and the stakeholders chose a remediation technology designed to meet the client’s needs, to fulfill the school’s requirements, and to satisfy the Consent Decree with the Washington State Department of Ecology.

Farallon staff provided construction management and compliance monitoring during the installation of the system.  The remediation system components were installed during an aggressive 10-week construction schedule necessary to accommodate school operations.  Farallon manages the hot water flushing remediation system, which requires the remediation to be implemented without disrupting school operations.  During remediation activities, Farallon performs project management and annual compliance monitoring and reporting.  

Farallon managed the system design, installation, and operations startup activities on schedule, without disrupting school activities, and our client is seeing progress.  Farallon has overcome obstacles, including biofouling, to keep the remediation activities on track.  Farallon is aggressively working toward completion of treatment goals ahead of schedule for the nonaqueous-phase liquid recovery remediation system.