Date: September 1, 2011
Sally Benson, Professor
Samuel Krevor, Post-Doctoral Researcher
PALO ALTO, CA — Our team led by Professor Sally Benson is measuring ambient carbon dioxide concentrations and isotopic carbon measurements from carbon dioxide at a site near Green River, Utah where there is leakage of CO2 along faults above a natural subsurface CO2 reservoir. The site presented an opportunity to test out methods for monitoring for CO2 leakage at the surface over the large areas that will be necessary for industrial CO2 sequestration projects.
We used a Picarro isotopic carbon analyzer for the project. In a novel platform, we performed gas surveys in the backcountry with the instrument carried by a pack mule. The analyzer was placed in a hard-shell aluminum saddle bag with a custom-made structural framework which included rubber shock absorbers to protect the instrument. Deep-cycle marine batteries were used to provide power. Other gas analyzers are too large and weigh too much to be used in such an application. In addition, the Picarro instrument's insensitivity to shock, vibrations, temperature, and pressure changes in the ambient environment made it ideally suited for this field activity.