Dynegy consultants have estimated it could cost up to $192 million to transfer 3.3 million cubic feet of coal ash from the Vermilion plant to a licensed landfill. The company once suggested it could cap the waste pits to prevent rain and snowmelt from washing coal ash into the water, but another Dynegy report estimated the normal flow of the Middle Fork is eroding the river banks by up to 3 feet a year, making it more likely the toxic slurry will be exposed if left in place.