1. The May 18, 1980 eruption of Mount St. Helens, a volcano located in the state of Washington, was the only major volcanic eruption to occur in the United States since 1915. At 8:32 a.m., an earthquake caused the mountain’s north side to break apart. The north side of the volcano was already weakened by months of small earthquakes and eruptions. The volcano released a violent eruption of scalding ash, rock, and gas that destroyed everything in its path over an area of 230 square miles.
2. Additionally, the debris from the volcano formed an avalanche which collided with nearby Spirit Lake, creating a tsunami which rose to heights of 850 feet, devastating nearby mountainsides. About 143 square miles of trees and other plants were completely destroyed.
3. The pyroclastic flow raged out of the volcano at speeds of up to 125 mph and reached temperatures of up to 1,200 degrees Fahrenheit. Mudflows, also known as lahars, scoured and buried much of the landscape, killing most of the plant and wildlife in their path. Ash rained down on towns and cities hundreds of miles away from the volcano. The ash was carried by the blowing winds. The 1980 eruption of Mount St. Helens claimed the lives of fifty-seven people and thousands of animals. And it caused approximately 3 billion dollars in damages.
4. The U.S. Geological Survey (USGS) has been monitoring Mount St. Helens since 1980. Less violent eruptions began in October 11, 2004 and continued until July 10, 2008. Of all the active volcanoes in the U.S., the USGS says Mount St. Helens is the most likely to erupt again. However, scientists do not believe the volcano will erupt any time soon.
5. A scientist from the USGS states that "Every eruption that we observe contributes some new clues about volcanic systems, and opportunities to test equipment and warning systems useful for saving lives at volcanoes in the U.S. and around the world." "Mount St. Helens has become our ‘go-to backyard volcano’ for testing volcano monitoring tools and models applied to understanding re-awakening volcanic systems."