http://www.greencarcongress.com/2014/11/20141118-sng.html This...

http://www.greencarcongress.com/2014/11/20141118-sng.html

  This may be an above ground plant, but the process is very similar if you think of the gasifier in CNX's would be underground.
  Note, The methanation unit putting out high temperature heat, which is easily captured and turned into electricity as a by product. This would be similar to CNX's plant as well.

Now where is the approval?