The arena that’s attracted acts such as George Jones and CCR is back in action.After more than a decade of inactivity, the amphitheater atop Harrison Ferry Mountain is ready for a musical eruption.Stonewood Bluff, the site formerly known as Pish-La-Ki, is preparing for a three-day music festival featuring jams, camping, and 30 bands. Folk Fest at Stonewood Bluff is set for May 5-7 with a lineup that includes music, food, and a variety of vendors.“This has gotten huge and there’s real excitement,” said organizer Mandah Morris. “We have some award-winning singer-songwriters on the schedule who are great performers.