Among the Ayta people of Mount Pinatubo it was a portent. A steam cloud that smelled like rotten eggs was rising from the peak, which they called Apo Mallari--"the father of our people." For generations these Filipinos had hunted and farmed its slopes, until strangers came with drills and dug deep holes in the mountain's sides. Now, their "father" was fuming.
On April 4, 1991, a Catholic nun who worked among the Ayta came to Manila, just 54 miles southeast of Pinatubo, and brought word of this steam cloud to Raymundo Punong-bayan, a geologist and director of the Philippine Institute of Volcanology and Seismology (PHIVOLCS). Punongbayan knew that the Philippine National Oil Co. had been drilling test holes in the Pinatubo area to determine the potential for geothermal electric production.
"So the Aytas believed their god got angry. And we had a hard time convincing people the drilling did not ...