who was president when mt st helens erupted
Jimmy Carter
1980 eruption of Mount St. Helens
Approximately fifty-seven people were killed directly from the blast and 200 houses, 47 bridges, of railways and of highway were destroyed; two people were killed indirectly in accidents that resulted from poor visibility, and two more suffered fatal heart attacks from shoveling ash. U.S. President Jimmy Carter surveyed the damage and said it looked more desolate than a moonscape.

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1980 eruption of Mount St. Helens [SEP] Direct results
At least 25% of the destroyed timber was salvaged after September 1980. Downwind of the volcano, in areas of thick ash accumulation, many agricultural crops, such as wheat, apples, potatoes and alfalfa, were destroyed. As many as 1,500 elk and 5,000 deer were killed, and an estimated 12 million Chinook and Coho salmon fingerlings died when their hatcheries were destroyed. Another estimated 40,000 young salmon were lost when they swam through turbine blades of hydroelectric generators after reservoir levels were lowered along the Lewis River to accommodate possible mudflows and flood waters.