Use of Forced Mineral Trapping for Sequestration of CO2

Among the options being considered to help mitigate anthropogenic CO2 emissions is carbon sequestration in depleted oil or gas wells, coal seams, and deep underground saline formations. One of the uncertainties that must be addressed with respect to geologic sequestration is the long-term risk associated with storage of large quantities of CO2 in the subsurface. Rapid release of CO2 could occur from reservoir failure due to seismic events, overpressurization, or other mechanical failures. In addition to the consequences of releasing the stored CO2 back into the atmosphere, a potential asphyxiation risk to a local population exists because CO2 is heavier than air, so it tends to stay near ground level until dispersed. Holloway (HOLLOWAY, 1997) discusses several fatalities that have resulted from catastrophic but naturally occurring CO2 releases.