So that means tanks are going to have to be cleaned out, roofs are going to have to be cleaned, because it is not the sort of thing that you drink, so all that sort of work has got to be done.he is also warning residents that Coonabarabran's water supply is likely to be contaminated by ash.We have got problems with water pumps at our dams, it came over our dam as well, he said.We are going to have