What ifs? the most common questions about CCS
Geological time is measured in the millions of years, not just in hundreds or thousands. The naturally occurring CO2 deposits that exist in the world - many of them in underground formations similar to the Weyburn and Midale oilfields - have remained stable and in place for tens of millions of years.
CO2 storage sites are chosen for the ways in which they are similar to these exact sorts of natural storage sites.