A VETERAN SEPTA electrical worker was recovering last night after a close call on the subway tracks in Center City, officials said.

The unidentified worker, 52, was held overnight at Hahnemann University Hospital after he was clipped by a Market-Frankford El train, according to a law-enforcement source who said "his prognosis is optimistic."

All things considered, the worker, a 27-year veteran of the transit authority, was extremely lucky: His brush with the train left him with only a long gash on his forehead and a knee injury, the source said.

The train hit the man about 4:15 p.m. as he was working on the power lines on the inactive trolley tracks near the station at 22nd and Market streets, said Jerri Williams, a SEPTA spokeswoman.

The trolley lines have been closed in recent days as the transit authority completes its renovation of the tunnels serving them.

Williams said that the worker was part of a full crew of laborers working to finish that project ahead of its deadline next week.

The worker "misjudged the distance" between the active tracks of the El and the trolley tracks, Williams said.

As he was leaning into the El track area, his back was hit by the passing train, which dragged him several feet before stopping.

"Our main concern now is the investigation," she said. "With an employee injured like this, it's very important that we find out exactly what happened."

Part of that probe will include reviewing footage from nearby security cameras, and ensuring that all signals and other equipment were in working order at the time, Williams said.

Service on the El was suspended for about an hour after the incident, Williams said.