A 17-year-old District youth whose legs and left arm were severed four years ago when he was struck by a train in the Conrail yard near Benning Road and Minnesota Avenue NE was awarded $1.5 million yesterday by a federal jury here.

Derek Foshee, of 504 Park Rd. NW, was awarded the money from the Consolidated Rail Corp. and his parents were awarded $70,000 to reimburse them for medical expenses.

Foshee was injured July 25, 1982, when he and six other children attempted to cross the Conrail tracks, which his attorney Michael Abelson said was a route often used by residents of the River Terrace area to reach shopping areas along nearby Minnesota Avenue. There is a bridge over the rail yard, Abelson said, but residents rarely used it.

Abelson argued that Conrail was aware residents had used the shortcut across the tracks for nearly 30 years, but did nothing to thwart the practice, such as erecting fences.

Although Foshee does not remember what happened that day, Abelson said testimony during the two-week trial showed that the other children noticed Foshee had been struck after about half of the mile-long northbound freight train had passed by.

He also suffered a fractured skull and a brain contusion.