While we are not surprised at this listing at all, they state in the article that the mining districts themselves (and those who are members of it) could be liable for environmental issues. https://www.washingtonpost.com/news/energy-environment/wp/2016/09/07/colorado-gold-mine-is-one-of-the-epas-new-superfund-pollution-sites/?utm_term=.fd38ed62191f