Lots of speculation, based on .....?
The owners, and the previous owners, are on the hook for the clean-up.
And you would be surprised at how easy it is to clean up the site of a previous refinery.
Doesn't take long and doesn't cost that much.
Example:
I worked here in the late 80s into the 90s:
They shut it down and finished tearing it down several years ago maybe 5 I'm guessing, maybe a little longer.
They then remediated the site and sold it.
This is what it looks like today:
The cost to clean it up was a tiny fraction of what the land was worth.
Oil refineries are cleaner than most people think.