In a preferred embodiment, {HEAD ~ a comparison} between the current pit volume and the previous recorded pit volume may be graphically displayed to {TAIL ~ the drilling operator} in real time 
graphically displayed to
In a preferred embodiment , { HEAD ~ a comparison } between the current pit volume and the previous recorded pit volume may be graphically displayed to { TAIL ~ the drilling operator } in real time
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH