ESPINSIGHTQuite simply the difference between the two processes...

ESPINSIGHT

Quite simply the difference between the two processes is that above-ground gasification mines the coal, brings it to the surface and gasifies the coal whereas UCG leaves the coal underground and performs the gasification underground. You can imagine there are major differences between the 2 processes most importantly the coal sites selected. I could go on but I think it would bore most people including myself :)