UPDATE 1-BP Texas City hydrotreater ops normal -sources

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HOUSTON, May 27 (Reuters) - A cat feed hydrotreater was operating normally on Wednesday at BP Plc's (BP.L) 467,720-barrel-per-day (bpd) Texas City, Texas, refinery despite a hydrocarbon leak into cooling tower water, according to sources familiar with refinery operations.

The source of the leak has been isolated without shutting or modifying unit production, according to the sources.

A cat feed hydrotreater uses hydrogen to remove sulfur from gasoil, the primary feedstock for a gasoline-producing fluidic catalytic cracking unit. (Reporting by Erwin Seba; Editing by Christian Wiessner)