VAV!/March 27, 2012
March 27, 1980, steam venting started on Mount St. Helens, in Washington State. By April's end, the north side of the mountain had started to bulge.
On Sunday morning of May 18, 1980 at 8:32 a.m., a second earthquake of magnitude 5.1 (the first quake occurred March 20, 1980), triggered a massive collapse of the north face of the mountain. Mount St. Helens magma spewed forth in a catastrophic eruption and was the deadliest and most economically destructive volcanic event in United States history. Fifty-seven people were killed; an estimated 250 homes, 47 bridges, 15 miles of railways, and 185 miles of highway were all destroyed in the wake of this event.
This volcanic volatility came as no surprise to geologists of the U.S. Geological Survey who'd predicted this eruption at least two years earlier.
In 1982, President Ronald Reagan and the U.S. Congress established the 'Mount St. Helens National Volcanic Monument,' a 110,000 acres area surrounding the mountain and within the Gifford Pinchot National Forest.