Preferably, hydrogen is introduced into {TAIL ~ the coal bed} in an amount within the range of 0.2–1.0 standard cubic feet of {HEAD ~ hydrogen} for each standard cubic foot of methane recovered from the coal bed formation 
Preferably , hydrogen is introduced into { TAIL ~ the coal bed } in an amount within the range of 0.2–1.0 standard cubic feet of { HEAD ~ hydrogen } for each standard cubic foot of methane recovered from the coal bed formation
OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH