[telgareith]

That sounds like a lot of it ends bound to, and thus comes up with, the oil/crude.

[ewhanley]

It absolutely does and has to be stripped out in processing. It typically gets compressed and reinjected over and over again

[alach11]

Exactly. And getting back to the original poster's comment "the CO2 starts underground and ends up underground"... that assumes there are no leaks anywhere in the process.