Near-surface soil carbon detection for monitoring CO2 seepage from a geological reservoir

The promise of the Brookhaven National Laboratory (BNL) Inelastic Neutron Scattering (INS) System was evaluated for use as a long-term, in-field monitor to detect cumulative changes in belowground carbon resulting from the leakage of CO2 stored in deep geological reservoirs. This system underwent tests at a facility constructed specifically for testing, under controlled conditions, various detection systems for monitoring near-surface transport and accumulations of CO2 fluxes emanating from a shallow buried, slotted horizontal well. The INS System was assessed by comparing the results from placing it above the horizontal well at a spot with a known high CO2 leak identified and quantified the previous years, with those obtained from background readings adjacent to the well. At two different “Hot Spots”, a suppression of about 14% in 2008 and about 7% in 2009 in carbon content above the well in comparison to the background signal was observed. An overview of these results is presented.

[1]  Sally M. Benson,et al.  Measuring permanence of CO2 storage in saline formations: the Frio experiment , 2005 .

[2]  Jens Birkholzer,et al.  A controlled field pilot for testing near surface CO2 detection techniques and transport models , 2007 .

[3]  S. Benson,et al.  Temporal Variability of Surface CO2 Emissions at the Horseshoe Lake Tree Kill, Mammoth Mountain, CA , 2006 .

[4]  Curtis M. Oldenburg,et al.  Surface CO2 leakage during two shallow subsurface CO2 releases , 2007 .

[5]  W. C. Evans,et al.  Forest-killing diffuse CO2 emission at Mammoth Mountain as a sign of magmatic unrest , 1995, Nature.

[6]  D. E. Anderson,et al.  Eddy covariance measurement of CO2 flux to the atmosphere from an area of high volcanogenic emissions, Mammoth Mountain, California , 2001 .

[7]  H. Rogers,et al.  Nondestructive System for Analyzing Carbon in the Soil , 2008 .

[8]  J. G. Atherton,et al.  Effects of elevated carbon dioxide and ozone on the growth and yield of spring wheat (Triticum aestivum L.) , 1997 .

[9]  Salvatore Lombardi,et al.  Gas migration along fault systems and through the vadose zone in the Latera caldera (central Italy): Implications for CO2 geological storage , 2008 .

[10]  Hardy Pfanz,et al.  Small-scale spatial variation in soil CO2 concentration in a natural carbon dioxide spring and some related plant responses , 2006 .

[11]  S. Whittaker Investigating Geological Storage of Greenhouse Gases in Southeastern Saskatchewan: The IEA Weyburn CO 2 Monitoring and Storage Project 1 , 2004 .