Unfortunately it's theoretical and replete with unresolved questions that leave "CCS" an unproven option. While a pilot project is being run in Saskatchewan, no one has run a successful operation on the scale that would be needed to sequester carbon emissions from the Tar Sands.
But, assuming that the empty reservoirs beneath Alberta could be used to house massive volumes of liquid carbon dioxide, what then? There's a huge problem. That pressurized CO2 could leak out and when it reaches the surface it's very lethal. So you have to monitor what's happening underground and on the surface and somebody may have to compensate anyone damaged (i.e. "killed")
The province, the Alberta conservatives, say there'll be a fund into which the province and Big Oil will chip in to monitor the CCS wells. That's probably true, at first. However scientists warn that the need to monitor will do on effectively for ever, millenia at a minimum. So does anybody think Big Oil is planning on picking up the cost of that monitoring into perpetuity? What a joke.
But then there's the leakage thing, compensating the dead and injured. Big Oil isn't even sticking around for that one. In fact the sweetheart deal the Alberta Cons have cooked up leaves the people of Alberta liable - forever and ever, amen. And, as Andrew Nikiforuk points out in Tar Sands, Dirty Oil and the Future of a Continent, not only is the rock vulnerable to failing under the pressure of liquified CO2 but that area is perforated with drilled wells, 300,000 in all. In other words it's just a matter of time before there's a failure and large volumes of lethal, concentrated CO2 reach the surface.
CCS sounds good until you look at it and read between the lines of the deal that Alberta has cooked up with Big Oil. Then it begins to look like a formula for disaster.