Mexico City Muddied by Ash From Nearby Volcano

Millions of Mexicans awoke to find a layer of volcanic mud on this capital Tuesday.

Many donned facemasks and goggles to scrape their windshields, hose down sidewalks and head to work after the nearby Popocatepetl volcano spewed its largest ash cloud in 72 years. It had mixed with overnight rain to form a messy sludge.

The eruption Monday night at the snowcapped 17,887-foot mountain southeast of here snarled air traffic at Mexico City’s international airport. The ash plume, more than 4 miles high and 34 miles in diameter, forced authorities to shut down runways several hours before the airport’s scheduled closing time Monday night.

As the towering crater continued to smoke and spit out sulfur dioxide fumes throughout Tuesday--a relatively common event since it became active in December 1994--federal disaster officials and government scientists called for calm, stressing that the volcano had returned to “normal.”

The message was aimed in particular at the more than 100,000 residents of the 30 villages that ring the base of the volcano, which was named “Smoking Mountain” by Mexico City’s first settlers. The officials also sought to explain the confusion that led to erroneous reports of a “red alert” at the peak of Monday night’s eruption.

A red alert would have meant evacuation of more than 100,000 of the volcano’s neighbors, many of whom still resent a December 1994 evacuation during which they say dozens of homes were looted and many of the evacuees fell ill in cramped shelters.

“A red alert was discussed . . . but we never did start to evacuate the villages closest to the volcano,” said Ricardo Garcia Villalobos, the federal government’s deputy interior secretary for civil protection. “But yes, we were ready to do that if we had to.”

Garcia added that national and foreign media apparently misunderstood a comment by the governor of Puebla, which borders the volcano. He said Gov. Manuel Bartlett told reporters “ ‘the red lights are on,’ meaning that we were ready. But that’s different than saying the alert had switched from yellow to red.”

A yellow alert, which requires residents to listen for alarm sirens and prepare to evacuate on short notice, was in effect Tuesday, Garcia said.

Mexican scientists stressed that there is less than a 10% chance of an imminent major eruption at the mountain, known as Popo.

Hugo Delgado of the National Autonomous University of Mexico’s Institute of Geophysics, which monitors the mountain for the government, said seismic activity inside the volcano “was a little higher” on Monday night than in recent months.

“The mountain is showing an increase in the emission of gases, particularly sulfur dioxide, as would be expected, but it is not something completely out of the normal range we have been seeing,” he added.

Popo’s last eruption was in 822.

Times staff writer Kenneth Reich in Los Angeles contributed to this report.

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Volcanic Landscapes

Mexico City residents awoke Tuesday to discover the capital awash with sludge. Overnight, rain had mixed with ash that spewed several miles into the air from the Pococatepetl volcano, 45 miles to the southeast. Monday’s eruption was the largest since 1925. Story A4