Saw metal conduit even with the floor?
I'm assuming you don't have access to the backside of this conduit.  If you did, you would just disassemble it - find the nearest coupler, uncouple it, and remove the pipe.  

Remember to remove these orphan wires entirely; all the way back to the previous junction box (or past it, if they go past it).  You're not supposed to leave orphan wires, though.