May 9 (Reuters) – U.S. refiner Valero Energy Corp (VLO.N) said on Tuesday CEO Joseph Gorder would step down from the role on June 30 and named Chief Operating Officer Lane Riggs as his successor. Gorder has led Valero as CEO since May 1, 2014 and served as chairman of the board since Dec. 31, 2014. Gorder … Read more