Once America's largest overseas air base, this strategic military installation may be permanently crippled, U.S. officials said Sunday as damage reports continued to grow from last week's devastating eruption episode of Mt. Pinatubo.
A six-hour tour of Clark showed that the eruption spewed a deadly wave of superheated gas, rocks and mud up to 20 feet high down a river valley only a few hundred yards behind an officers' housing complex and elementary school. It also sent waist-deep mud and swirling water across parts of the base, damaging the hospital and washing cars and trucks away.
At least 30 huge aircraft hangars, warehouses, a gymnasium and other buildings were crushed by the heavy gray ash, which blankets runways, roads and rooftops up to a foot deep in places. Falling trees damaged homes, a school and other structures.
With 10 new volcanic explosions on Sunday, more ash continues to rain down on Clark, only about eight miles away. Worse, scientists say Mt. Pinatubo may remain active for up to three years, spewing volcanic debris that endangers lives, threatens aircraft and fouls sensitive communications equipment.
"It'll take a long time to get Clark back and operating, if ever," Stanley Schrager, U.S. Embassy spokesman in Manila, said Sunday.
Lt. Col. Ron Rand, a Clark spokesman, said it's not clear if the Air Force can use runways and fly so close to an erupting volcano. The ash is much finer than the desert sand pilots overcame during the Persian Gulf War.
"I don't think we know enough about it except it's dangerous," Rand said. "What we have here is more like a talcum powder. When it gets dry, it gets everywhere. So no one's going to rush into flying any time soon."
Also, the searing gas, steam and mud that roared at least 10 miles down the Sacobia River--a short walk behind dozens of ash-covered homes, broken trees and the partially collapsed Grissom Elementary School in Clark's Mactan housing complex--indicate that the base is directly endangered by future eruptions.
"If you're in the way of a pyroclastic (rock material broken into fragments) flow, it's a terminal event," said Ed Wolfe, a geologist at Clark from a U.S. Geological Survey team. "You don't want to be there."
The Pentagon has temporarily transferred some of Clark's essential operations--including training, airlift capability and special operations--to other bases in the western Pacific, particularly Guam and Okinawa. Officials say the transfers may become permanent if Clark is deemed inoperable.
Abandoning Clark, a major military logistics and training hub, would force the Pentagon to reorganize supply lines and defense strategy for the western Pacific and Indian Ocean. The base, initially built for cavalry, was begun in 1901 as America's first overseas base and has been a key Pacific bastion since World War II as headquarters of the 13th Air Force and home of a sophisticated aerial combat and bombing range.
Demolition teams destroyed surplus munitions stored on Clark--1,000-pound bombs, grenades and ammunition--for three days last week. At least some were water damaged, one official said, despite entombment in earth-covered concrete bunkers.
No precise figures are available, but including cleanup the June 15 eruption is likely to cost hundreds of millions of dollars at Clark and the equally stricken Subic Bay Naval Base and dockyard, where more than 122 buildings were badly damaged or destroyed.
Subic's activities may be temporarily relocated as well, officials said, but no decision has been made yet. Subic is less likely to close permanently since its ship repair, refueling and resupply facilities are easier to maintain.
The eruption occurred just three months before leases expire for the bases. A year of contentious negotiations to extend the leases stalled in May, with Manila demanding $825 million a year and Washington offering $360 million. Officials say it's unclear when talks may resume or under what conditions.
At least 1,500 active-duty Air Force personnel from Clark have been evacuated by aircraft carrier from Subic Bay, joining more than 20,000 military dependents and Defense Department employees. All have been taken to Cebu, about 200 miles south, for flights to Guam and to the United States.
The evacuation leaves a skeleton force of 1,500 Air Force police, engineers and others at Clark. Another 5,000 Air Force personnel and 7,000 Navy sailors are housed at Subic, where a massive cleanup and repair effort has barely begun.
At Clark, virtually every tin-roofed hangar and storage shed along the flight line crumpled and collapsed from the sheer weight of the volcanic debris. The roof of a three-story maintenance hangar for the 353rd Special Operations Wing collapsed on cots and bedrolls installed in case the building was needed as an evacuation center. It was empty when it collapsed.
A wall of mud and boulders pushed a dozen vehicles 150 feet off a new car lot, leaving them as scattered wrecks. Scores of other vehicles lie abandoned in the mud. Floodwaters damaged the base commissary and exchange, two floors in the hospital and numerous homes and offices.
A few cleanup crews shoveled ash off rooftops, but most of the 9,200-acre base--shrunk from 150,000 acres after a 1979 agreement returned most of the facility to the Philippines--appeared eerily empty. Even roads that had been cleared were treacherous: A pickup truck that tried to drive over a tall drift of ash got stuck, as on snow, with its wheels spinning.
Rand said it will take weeks before the full extent of damage is known and months before repairs can be made.
Since Mt. Pinatubo's eruptions began June 9, the death toll has climbed to 309 people, Philippine military sources said. Three people were killed Sunday when a public market collapsed in Floridablanca because of strong winds and the weight of volcanic ash.
Floridablanca is about 12 miles south of Clark Air Base.
With heavy monsoon rains drenching western Luzon almost every day, Philippine officials stepped up warnings Sunday for tens of thousands of people to flee riverbanks and low-lying areas in case landslides and mudflows come crashing down the mountain into surrounding towns and villages.
"I've seen the mountain of sand and mud on top of Mt. Pinatubo with my own eyes," said a senior Philippine air force official who flew over the slopes in a helicopter. "It's no joke. It's a whole dam up there on top of the mountain that's going to break. That would be some catastrophe."
It was unclear if many people in the worst-hit areas were heeding the warnings. Few have radios, many roads are impassable and communications remain badly damaged. An estimated quarter-million people were made homeless by the volcano.
"If you're asking me if word gets to these people, your guess is as good as mine," the official added.