Cerro GrandeMay 10, 1872: U.S. President Ulysses S. Grant signs the General Mining Act of 1872. The law, which is largely unchanged to this today, still allows hardrock mining claims on federal lands for as little as $5 per acre and leaves U.S. taxpayers largely responsible for cleanup of abandoned mine sites.

May 10, 2000: Los Alamos, N.M., the laboratory town created for the Manhattan Project and the creation of the first nuclear weapons, is evacuated as a wildfire destroys nearly 300 homes in the town. The Cerro Grande fire is the result of a "controlled burn" that went out of control (at right). Intentionally set fires are a standard tool used by foresters to prevent larger wildfires.

May 10, 2007: The World Wildlife Fund (WWF) issues its list of the "Dirty Thirty" — the most polluting electric power plants in Europe. The U.K. and Germany each have 10 plants on the list, but Greece claims the dirtiest two. All 30 qualifiers are coal-burning plants.

Photo: Robyn2175/Flickr

This feature is compiled by Peter Dykstra, an MNN contributor and publisher of Environmental Health News and The Daily Climate.