Only nine of the men working in the mine at the time of the disaster were able to escape, after one of them got to safety and returned with a rescue team and equipment.
The late environmentalist, Sen. Gaylord Nelson, D-Wis., founded Earth Day as an environmental teach-in first held on April 22, 1970.
Positions of authority, millions of dollars of personal wealth, slick public relations consultants, $1,000 per hour lawyers, privilege, and power cannot conceal the true purpose of this bankruptcy.
Just how old and how badly in need of upgrading is the U.S. power grid?
Unionists and environmentalists face common enemies - in corporate suites and Congress.
Deaths and injuries in the nation's mines, including its coal mines, fell in 2012 to some of their lowest recorded levels.