At one point, this city produced so much copper it was nicknamed the "richest hill on earth." Now, it has a toxic lake filled with acid that will cost the industry billions of dollars to clean up. Editor's note: Butte's Residential Metals Abatement Program (RMAP) removes attic dust that accumulated in homes built before 1980 – the same year the biggest and only smelter in nearby Anaconda, MT shut down. The dust from active mining is monitored and tested by the mine, government agencies and third parties. To date the results have been below state and federal action or advisory levels for arsenic and/or heavy metals. Montana Resources continues to study and improve dust control measures in compliance with a state air quality permit, according to Matt Vincent, Rampart Solutions, an environmental solutions company. MORE WORLD WIDE WASTE VIDEOS: Meet The Man Who Shoots At Birds All Day To Keep Them Off A Toxic Pit | World Wide Waste youtube.com/watch?v=qtlPTE-UmY4 Why Wind Tu...