HOUSTON, March 27 BP Plc said on Thursday that more oil than previously thought may have leaked into Lake Michigan this week from its Indiana refinery.
The British major now estimates between 15 and 39 barrels had spilled - more than an earlier assessment of nine to 18 barrels for the Monday leak.
BP said crews have recovered the "vast majority" of oil that had been visible on the surface of the lake and its shoreline.
The leak occurred after a malfunction of a recently upgraded crude distillation unit, the largest at the refinery, which went through a $4-billion overhaul to boost output. (Reporting By Kristen Hays and Erwin Seba; Editing by Terry Wade)