Landfill Gas Extraction

Farallon designed and provided oversight for the 2004, 2005, and 2007 Coffin Butte Landfill gas extraction well system projects in Corvallis, Oregon. The projects included installation of 86 wells into municipal refuse at the landfill over a 4-year period.

Design work involved evaluating the performance of previously installed landfill gas wells to assess the effects of water mounding on the effectiveness of well-screen depths. Based on this evaluation, Farallon developed the design and layout for the new well systems.

Farallon also provided engineering assistance during well drilling and completion. Additional elements of the project included the design of more than 30 horizontal landfill gas collection trenches subsequently installed by the landfill owner, and the design, construction, and start-up of a 2,000-cubic-feet-per-minute landfill gas flare. Farallon continues to monitor the landfill gas system, provide technical support for future expansion of the landfill, and make presentations with the landfill owner at public hearings.