UPDATE 1-Shell Deer Park begins gasoline unit restart-state

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HOUSTON, Feb 3 (Reuters) - Shell Oil Co's joint-venture 340,000 barrel per day (bpd) Deer Park, Texas refinery began restarting gasoline production units on Sunday after a planned overhaul, according to a notice filed with state pollution regulators.

The refinery's 70,000 bpd gasoline-producing catalytic cracking unit, gasoline hydrotreater, an alkylation unit, three sulfur recovery units and a girbotol unit will be restarted between Feb. 3 and March 1, according to the notice filed with the Texas Commission on Environmental Quality.

The units were shut on Jan. 17 for inspection, cleaning and repairs, according to the notice. Crude oil throughput at the refinery was reduced by an unspecified amount while the units were being overhauled.

The Deer Park refinery is a joint venture between Shell Oil and Mexico's state-owned oil company Pemex. Shell Oil Co is the U.S. unit of Royal Dutch Shell Plc (RDSa.L: Quote, Profile, Research).

The Deer Park refinery is the sixth-largest in the United States. (Reporting by Erwin Seba; Editing by Diane Craft)