Geologists Taking Pulse Constantly of Colombia Volcano, Hoping to Avoid Disaster

A scientist sits 24 hours a day in an observatory in southern Colombia watching a seismograph trace the activity of a volcano that threatens to spew tons of lava on the city below.

Galeras volcano, which overlooks Pasto, a city of 50,000 inhabitants, has been spitting ash and coughing smoke since late February, prompting the government to send a team of geologists there to monitor its activity.

No one knows if the volcano will erupt. But if it does, lava could inundate the city, which lies just four miles away.

A film of ash rained down on Pasto on March 28, leading authorities to step up their alert, the head of the government’s geological team, Hector Cepeda, told Reuters.

The alert put firefighters on standby and called for mock evacuation exercises and a ban on traffic near the crater.

Cepeda said the volcano in Narino province, which stands near the border with Ecuador, was last active in 1950.

Five scientists share a 24-hour watch on Galeras in an effort to avoid a repeat of Colombia’s worst natural disaster, when the Nevado del Ruiz volcano in central Tolima province erupted in November, 1985, and buried the city of Armero, killing 23,000 people.

“The Nevado del Ruiz disaster happened because scientists were not monitoring it 24 hours a day,” Cepeda said outside the observatory on a hill facing the volcano. Pasto’s white houses and its coffee-colored colonial church lay below.

“We’re hoping our presence here will avoid a disaster like Nevado del Ruiz,” he said, looking at the volcano embedded in white clouds. Later, as the afternoon wore on, a vague orange glow and a black sulfurous smoke column appeared from the crater as the clouds lifted.

Cepeda said the scientists are using four seismographs to measure movements in the volcano’s structure. They are also operating a tiltmeter and electronic distance meter for recording changes in the surface area and a correlation spectrometer for measuring gas buildup.

Distinguished volcanologists Norman Banks of the U.S. Geological Service and Jean Jacques Wagner of Geneva University have visited the team and advised them on monitoring Galeras, Cepeda said.

He said it is not certain the volcano will erupt and the scientists may continue to observe minor changes in temperature for months before activity dies down.

But even if that happens, he said, he will press the government to let at least one scientist continue to watch the volcano as a precaution against an eventual eruption.

Cepeda said the scientists have all the equipment and advice they need to monitor the volcano but that is no guarantee they will have enough time to warn the local population before an eruption.

“Some volcanoes have erupted in hours,” Cepeda said. “We just hope there won’t be a surprise in this case.”

A major eruption of lava would sweep away within minutes hundreds of huts lining the green hillside below the volcano, local officials said.

On the hillside the peasants played zapo, a local ball game, and drank aguardiente, an aniseed liquor, apparently oblivious to the threat hanging over them.

The local emergency committee is doing everything it can to minimize the impact of an eruption on Pasto, including mock evacuation and rescue exercises, Mayor German Guerrero told Reuters after a weekend meeting of the committee.

He said earlier that more than 600 residents took part in exercises in Pasto simulating the rescuing of lost people, extinguishing fires, treating injuries and recovering corpses.

The committee has opened a shelter where voluntary evacuees from the hillside could spend the night while the volcano remained active.

Appealing for more funds from the government to buy more ambulances and safety equipment to handle a disaster, he said, “We must try to reduce what could be a terrible disaster if the volcano erupts.”

Will it erupt? Taxi driver and Pasto resident Eduardo Santos Pantoja said, “No one knows. Only God knows.”