Attorney General Josh Stein and the Sierra Club want the N.C. Supreme Court to reverse a regulatory ruling that allows Duke Energy Progress to collect $230 million in coal-ash costs from customers. Those charges were approved by the N.C. Utilities Commission in a rate-case ruling in February. Duke defends the commission’s decision. “The North Carolina Utilities Commission’s order is the result of a transparent and thorough process, “ says spokeswoman Meredith Archie.