UPDATE 1-Shell reports Scotford unit work

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NEW YORK, Nov 13 (Reuters) - Royal Dutch Shell Plc (RDSa.L) said maintenance that had begun Thursday morning on a unit at its Scotford refinery in Alberta, Canada, would cause flaring for a 24-hour period, according to an information line message.

"We are conducting minor routine maintenance on one of our refinery units and will be flaring intermittently over the next 24 hours," a refinery official said in the recorded message.

No other details were given.

Shell had posted a similar message late Wednesday saying maintenance was underway at the 98,000 barrel-per-day refinery. Last month, Shell restarted several Scotford refinery units. (Reporting by Haitham Haddadin; Editing by John Picinich)