Review: No Apparent Danger: The True Story of Volcanic Disaster at Galeras and Nevado del Ruiz by Victoria Bruce

Bruce recounts the history, both geologic and historic, of the active volcanic range in Colombia. It's quite a story.

The Nevado del Ruiz eruption, when it came was horrifying. It wasn't one of those blow-the-tops off like Mt. St. Helens, rather an insidious flow of lava that melted several glaciers which then overran rivers and created a mudslide close to one-hundred feet high and traveled at about fifty miles per hour. It literally obliterated the town of Armero and killed more than 23,000 people. Ironically, there was warning. Ham radio operators living high in the mountains who saw what was happening sent warnings, but the local priest had broadcast calm reassurances saying it was just an ash rain so people even refused the frantic warnings of local firemen who had pounded on their doors insisting they evacuate. Only 5% of the icecap had melted. 85% of Armero vanished under the mud.

Following that eruption there was an increased interest in the volcanoes of the Andes and the next on the list was Galeras. Bruce does a great job of illuminating the social and political pressures on the scientists who by now had become quite interested in those wisps of steam coming from the top of the mountain. Everyone wanted accurate predictions of when the volcano would pop off and what form it would take.

(By the way, here is a nasty description of the dangers of pyroclastic flows: "an absolute death sentence that kills not from the heat but from inhalation of scalding hot ash. On the first breath, a person’s lungs react with instant pneumonia and fill with fluid. With the second breath, the fluid and ash mix and create wet cement. By the time the person takes a third breath, thick, hot cement fills the lungs and windpipe, causing the victim to suffocate. There were autopsy pictures of a surgeon opening a victim’s trachea with a chisel.")

As it turns out, a scientist by the name of Chouet had studied the seismic waves before eruptions of numerous volcanoes and he noticed some screw-like motions. "Chouet believed he knew what the signals were saying. Inside the volcano, in fractures in the rocks, boiling water turned to steam. And the steam, under great pressure and unable to escape, resonated brutally in the fractures, creating a high- frequency song like a boiling teakettle whistling an imperceptible pitch." Turns out he was prescient and accurate. Those little squiggles were predictive of explosive events.

On the fateful day, the scientists hiked up to the top and then roped down into the caldera to take measurements. The dome of lava, ever expanding, concerned several of them, but contrary to the pattern and habit of the U.S. Geological Survey scientists, hard hats and safety equipment was not present. No one was positioned on the top to relay radio signals nor did they have emergency medical supplies. Even some untrained journalists were invited to go along into the active volcano.

Nine people (five scientists) died when the volcano popped. Afterwards, one of the gas scientists claimed to have been the only survivor, an untruth, but then he had sustained severe brain injury and needed brain surgery so I suppose a little mendacity could be excused. Not so forgiveable was the appropriation by one of his students of the work of Chouet nor his insistence there was no warning. There was.

Riveting.