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