TOPEKA — The Kansas Department of Transportation has requested a third federal grant to expand passenger rail service in the state. KDOT is asking for $10 million to improve signals and crossings along the Burlington Northern Santa Fe tracks between Newton and the Oklahoma line. KDOT has already asked for more than $8 million for track improvements between Barclay in Osage County and Emporia. The state is hoping to add a segment to connect the Heartland Flyer between Texas and Oklahoma City and the Southwest Chief that runs through Kansas between Chicago and Los Angeles.