Long article about this, but not about the tax consequences, at

https://www.eenews.net/articles/why-injecting-co2-underground-is-a-legal-morass/

The carbon dioxide can mix with brine deep underground and produce carbonic acid, which can cause problems years from now.  So there should be some allowance for depletion or depreciation, but there isn't.  Maybe Congress will catch up with this issue in another decade or so.