GREELEY — A worker digging a trench on a northern Colorado ranch hit a high-pressure gas line, sparking an explosion that sent flames several hundred feet into the air and touched off a small grass fire. Sean Standridge, a spokesman for the Weld County Sheriff's Office, tells The Greeley Tribune (http://goo.gl/UJiZAB ) an employee for DCP Midstream hit the 12-inch gas line at the Wells Ranch east of Lucerne on Thursday afternoon.