Emergency officials are preparing themselves for a major eruption of the Turrialba volcano. Nothing is certain, and the mountain may go back to sleep. The worse-case scenario, they hope, is based on the eruption of its twin, Irazú, in 1963.
That eruption took began in March while President and Mrs. John Kennedy were visiting. Guillermo Alvarado, a volcano expert, said that a light amount of ash came down on the crowd as they were waiting on Paseo Colón for the Kennedys.
That eruption lasted until 1965. He said that a national emergency was declared and there were large quantities of ash that fell through the end of 1963
Alvarado also noted that the nearby rivers turned to mud and flooded, causing significant lost of property and the deaths of 20 persons.
Irazú and Turrialba are linked underground.
A writer cited by Alvardo in his book “Costa Rica: Land of Volcanoes” said this:
“Great black clouds covered a sky that had no blue, only a sad and melancholy gray. The residents of the valley looked toward the huge cloud over Irazú volcano with amazement and no little apprehension; from deep within, the volcano was furiously spewing out toward the heavens a black, colossal column of ashes, rocks and smoke which would change its shape from one minute to the next but without ceasing to grow, lighted occasionally by bright golden serpentines of lightning.”
The Irazú volcano can be approached on foot, so many Central Valley residents made the trek to the rim even as the mountain was erupting.
During the Irazú eruptions Central Valley residents dressed to protect their bodies from the ash. Estimates are that thousands of tons of ash fell on San José alone. The United States airlifted in four street sweepers, the report said.
Turrialba did not erupt Tuesday, but there were continual small earthquakes under the mountain.
That is why the experts are expecting more activity.
Of course, there are worse worse-case scenarios. When Mount St. Helens exploded 35 years go and launched a column 19 kilometers into the sky, the ash covered 11 U.S. states, noted the Red Sismológica Nacional.