providing a source of water for flowing through a floway, said water containing a quantity of pollutants and having a pH lower than a pH of precipitation of {HEAD ~ said pollutants} on {TAIL ~ entry} into said floway 
on
providing a source of water for flowing through a floway , said water containing a quantity of pollutants and having a pH lower than a pH of precipitation of { HEAD ~ said pollutants } on { TAIL ~ entry } into said floway
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH