After conversations today with the three industrial gas companies in the area it would appear the only economic use of the leftovers from this plants would be attracting a local business to use them, thusly avoiding the expense of liquefaction and transport.
We do have a ridiculously large county landfill here, which now towers above the landscape. A high performance incinerator might be nice, but those go over like the proverbial lead balloon. We'll stay silent about this until the rest of the process is moving, then let someone else dream that up and propose it.