UPDATE 3-Marathon Texas City, Texas refineries restoring production: sources

(Adds Marathon comment)

HOUSTON, May 8 (Reuters) - Marathon Petroleum Corp was restarting the 86,000 barrel-per-day (bpd) Texas City, Texas, refinery on Tuesday night after a substation fire knocked out power, said sources familiar with plant operations.

Marathon was also restarting normal production at the neighboring 459,000 bpd Galveston Bay Refinery in Texas City, the sources said. A 60,000 bpd resid hydrotreater was restarting at the big refinery.

A late afternoon fire on a Centerpoint Energy substation near Bacliff, Texas, 8 miles (12 km) north of the refineries, also disrupted production at Valero Energy Corp’s 225,000 bpd refinery in Texas City, the sources said.

Marathon spokesman Chuck Rice said in a statement that the company was evaluating operations at the Galveston Bay Refinery after a power dip in the Texas City area.

“Even though we have a cogeneration facility for the Galveston Bay Refinery, a larger power dip can affect our operations,” Rice said. “There were no evacuations or injuries.”

Cogeneration plants produce electrical power and steam for refineries.

The City of Texas City Emergency Management Office said refineries on the south side of Texas City were using safety flares as they worked to restore power on Tuesday.

A Valero spokeswoman did not reply to messages asking about operations at the Texas City refinery on Tuesday night.

The Valero refinery’s gasoline-producing unit was shut on April 19 following an explosion and fire on the alkylation unit at the refinery, the first of four fires at refineries and chemical plants across the United States in the past 2-1/2 weeks.

The Tuesday fire broke out on the Bacliff substation at about 4:30 p.m. CDT (2130 GMT) with flaring seen at the Marathon and Valero refineries about 20 minutes later, according energy industry intelligence service Genscape.

At about 6 p.m., Centerpoint said the fire, which was fueled by mineral oil inside the substation, was under control.

All personnel at the substation were accounted for and no injuries were reported, according to Centerpoint. (Reporting by Erwin Seba, editing by G Crosse and Cynthia Osterman)