"- the toluene and benzene were valuable then but other...

"- the toluene and benzene were valuable then but other end-products in the tar fraction can be really nasty and carcinogenic. As far as I can envisage the eventual contamination of groundwater is inevitable so this should be factored into process costings instead of being treated by "out of sight, out of mind"."

~ we respectfully suggest that this is about where u should be with your unfounded, sweeping negative statements and obvious lack of knowledge of the highly monitored UCG process of negative chamber pressure burns in sub-aquifer stranded coal seams, where it's more than likely there is a drawing IN of the local ground contaminants, which unfortunately don't appear to have included a few irritating species yet to be classified & catalogued.