Part of current Drainable Oil which is going to be recovered with positive profitability:
Drainable Oil = Profitable Oil Recovery + Non-profitable Oil Recovery
The Non-profitable Oil Recovery is a result of deviation from the current Field Development Plan (FDP) or mistakes in FDP itself, for example, the underestimation of the wells productivity.
See Also
Petroleum Industry / Upstream / Subsurface E&P Disciplines / Petroleum Geology / Oil In Place (OIP)/ Oil Reserves (OR) / Drainable Oil
[ Hydrocarbon Reserves ] [ Gas reserves ]