Ratings on Norfolk, Va.-based Norfolk Southern Corp. reflect its strong competitive position as one of the two large eastern railroads and the better-than-average risk profile of the U.S. freight railroad industry, offset by a somewhat aggressively leveraged (albeit improving) financial profile. Norfolk Southern operates the fourth-largest rail system in the U.S. It also owns and operates a 58% economic interest in Conrail Inc., the only major freight railroad serving the Northeast (CSX Corp. and Norfolk Southern jointly acquired the common stock of Conrail in 1997 and began operating their respective portions in mid-1999. Last year Conrail filed a petition with the Surface Transportation Board [STB] for approval to transfer the ownership of the operations run by Norfolk Southern and CSX