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HOUSTON, Aug 10 (Reuters) - BP Plc's Whiting, Indianarefinery was operating at about 75 percent of its 413,500 barrelper day (bpd) capacity on Wednesday due to reduced production atthe refinery's wastewater treatment plant, sources familiar withplant operations said.
A BP spokesman declined on Wednesday to discuss operationsat the refinery.
BP is carefully restoring the wastewater treatment plant'sproduction in order to avoid a malfunction like one last week,which led to greater than permitted releases of sediments intoLake Michigan, the sources said.
"Water flow dictates production flow," one of the sourcessaid.
The wastewater plant utilizes microbes to consumehydrocarbons before the wastewater is discharged into LakeMichigan. Those microbes grew out of control over the weekend ofJuly 30-31, overwhelming the plant's system for controlling thesolids like the sediment, the sources said.
The careful increase in wastewater plant production is tomake sure the microbes grow in a controlled manner, the sourcessaid.
During the same weekend at the end of July, a 60,000 bpdreformer, called Ultraformer 4, and a blending oil unit wereshut due to a malfunction. The reformer and blending oil unitrestarted last week. (Reporting by Erwin Seba; Editing by Phil Berlowitz)
