Substantial savings in drilling time and cost may be realized according to the present invention, along with {HEAD ~ benefits} of {TAIL ~ reduced environmental contamination} and enhanced well safety 
of
Substantial savings in drilling time and cost may be realized according to the present invention , along with { HEAD ~ benefits } of { TAIL ~ reduced environmental contamination } and enhanced well safety
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH