Controls for the process allow for a wide variation in {HEAD ~ the amount} of {TAIL ~ treatment chemicals} used, dependent upon composition of contaminants in the groundwater 
of
Controls for the process allow for a wide variation in { HEAD ~ the amount } of { TAIL ~ treatment chemicals } used , dependent upon composition of contaminants in the groundwater
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH