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A landslide is a mass of rock, earth, or debris moving down a slope. They are activated by rainstorms, earthquakes, volcanic eruptions, fires, and by human modification of the land.
Landslides and Mudflows
Thunderstorms and Lightning
Nuclear Power Plants
The May 1980 eruption of the Mount St. Helens volcano caused the largest landslide in history - a rock slide-debris avalanche large enough to fill 250 million dump trucks.
Contact your local or Installation's Office of Emergency Management for more information.