FILE PHOTO: A Valero Energy Corp. gas station is pictured in El Cajon, California, U.S., August 8, 2017. Picture taken August 8, 2016. REUTERS/Mike Blake/File Photo
FILE PHOTO: A Valero Energy Corp. gas station is pictured in El Cajon, California, U.S., August 8, 2017. Picture taken August 8, 2016. REUTERS/Mike Blake/File Photo