Post and Courier: Outside the high school here Tuesday night, as people gathered for a public hearing, three young women wrestled with a big black inflatable coal plant that looked similar to a jump castle — except for the words “CLEAN UP DIRTY COAL PLANTS NOW” on the side. One woman trying in vain to get the prop’s smoke stacks raised was Katheryn Hilton, 20, of Aiken, who two months ago spent 11 hours in jail after being arrested at a demonstration at a coal plant in Virginia. Hilton said coal is a …