FIG 1 illustrates these active mud pits P1, {HEAD ~ P2}, and {TAIL ~ P3} fluidly connected in series 
FIG 1 illustrates these active mud pits P1 , { HEAD ~ P2 } , and { TAIL ~ P3 } fluidly connected in series
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH