The lure of gold helped build the fledgling northern community of Yellowknife, NWT when the Giant Mine site opened in 1948, but that development came at a heavy cost. For more than 50 years, the mine pumped arsenic into the air, contaminating people, water and land. What didn't go up the stacks was squirreled away in the deep, dark mine shafts below the ground and forgotten, until recently. Today, there's enough arsenic buried there to kill everyone on the planet, and the federal government is racing to contain the poison before it leeches into life-sustaining land and waterways. It will cost a billion dollars to stabilize the site, and that's only a small part of the toxic legacy of development.