Decoding the Volcano's Message

By John S. DeMott

At Mount St. Helens: T shirts, bumper crops and suspense

It is the hottest show out of the West, competing with Disneyland and the tinsel of Hollywood. Visitors are flocking to it by the thousands. For sheer suspense it rivals even Hitchcock, continually hinting of ominous new surprises. The sulfurous center of all this attention is Mount St. Helens, site of the largest volcanic explosion in the U.S. in more than 60 years.

When the volcano erupted last May 18 with the force of 500 Hiroshima-size atomic bombs, it blew away a cubic mile of earth, killed at least 31 people (another 32 are missing and presumed dead), destroyed or damaged 220,000 acres of timberland and created a monumental dredging job on three nearby rivers. In the four months since then, the mountain has been restive but not cataclysmic. There have been four major eruptions and numerous smaller ones, the most recent on Aug. 15. But Mount St. Helens lets no one rest, especially scientists.

Last week harried U.S. Geological Survey workers noticed a quirky change in the volcano's gaseous emissions. Abruptly, the 5-to-1 ratio of carbon dioxide to sulfur dioxide dropped sharply to 2.4 to 1. Similar drops preceded at least two of the post-May 18 eruptions. That raised immediate concern that the volcano was about to blow again. But the ratio is no certain predictor. Says Geologist Bob Noble: "We don't have anything that's 100% accurate."

Tiltmeters on the mountain's north rim were showing a slight but growing deformation similar--but on a much smaller scale--to the bulge on the peak's north face before the May explosion. Scientists were not sure if it was caused by a swelling on the rim or the settling of material on the floor of the crater. Inside the crater a lava dome has been forming. It glows red as molten rock roils underneath its hardened crust. The questions: Will it be able to cap the volcano? Or will pent-up gases blast through again?

Almost anywhere in the , wedge-shaped 400-km^2 (150 sq. mi.) blast zone stretching north of the mountain, all appears to be devastated, a sea of gray volcanic ash. Geologists and biologists believe it will be decades before life comes back to the mountain's highest slopes. Yet lower down, in what looks like a totally forbidding, colorless world, life, incredibly, is returning. Deer tracks have been spotted on otherwise barren slopes; new growths of ferns and skunk cabbage are poking through the ash. Tree sprouts are "coming up beautifully," says John Allen, 72, geology professor emeritus at Portland State University.

In a few respects, the aftermath of Mount St. Helens did not live up to its worst billing. Concern in May over immense crop failures under the mantle of ash has proved unfounded. There is a bumper crop in hops, and the apple harvests, while not at record levels, are bountiful. In and around Ritzville (pop. 2,000), 310 km (190 miles) from the mountain, wheatfields are yielding a third more bushels than last year. In some ways, the ash did more good than harm: its slight acidity helped neutralize the alkaline soil, and it let the ground retain water from heavy rains in May and June. Says Ritzville Farmer John Wellsandt, whose wheat yield jumped from last year's 40 or 45 bu. an acre to as high as 78: "It acted as a kind of sealer."

Radioactivity proved to be minimal, as did the toxicity of the ash. At first public health officials feared that the silica content of the fallout could cause lung damage, and the number of pulmonary cases did increase for a time in some areas. But later tests showed that while the ash has a high silica content, only a small percentage of the particles are of the type that causes scarring of the lungs.

Local residents think that another bumper crop--of littering tourists in their Winnebagos and charter buses--may be a mixed blessing. At Drew's Grocery in Toutle, 40 km (25 miles) from the blast site, a 40-page guest register (the third since June) is filled with names from around the world: West Germany, Switzerland, Japan, France, Yugoslavia, Brazil, the Ivory Coast, Saudi Arabia. Says Clerk Shelley Cooper, 23: "We're not used to having all these tourists around. They're kind of rude, stopping their cars in the middle of the road. They pay no attention to signs that say 'Keep Out.' "

But not everyone has reason to complain, especially local entrepreneurs. Since June, Drew's has sold 1,800 T shirts with slogans like HELENS IS HOT at $6 apiece. "Genuine Mount St. Helens Volcanic Ash" goes for 50-c- to $1.98 a bag. Says Cooper: "We started sacking it, and it just cracks us up when people come in asking for it."

With a scoop, of course, anyone can get plenty of ash for nothing from Drew's parking lot or just about any other horizontal or sloping surface around. So much ash blankets the state that some natives have covered over the w on their automobile license plates to create ASHINGTON. The stuff is omnipresent. It clogs air filters on farm machinery, shorts out electrical equipment, seeps into auto carburetors. Fire fighters slip on five to ten inches of it as they battle the four or five blazes a day that ignite in the stumps and slash piles of the no man's land left by the blast. Says Bob Joens of the Forest Service: "It's like walking on marbles."

Aided by a special congressional appropriation of $218 million, the U.S. Corps of Engineers is busily dredging the Toutle, Cowlitz and Columbia rivers, all clogged with tons of mud. So far, the Corps has removed 10.2 million cu. yds. of silt from the Cowlitz alone. The goal is to restore the river's water flow from 3,500 cu. ft. per second now to 50,000 by Nov. 1.

All the while, scientists have been gathering data from the living laboratory of Mount St. Helens. Some 200 have been to the mountain, and hundreds of others have applied for permits through a committee of scientists, mainly from the Northwest, who are screening applicants on behalf of the U.S. Geological Survey. The screening process is anything but tranquil as scientists from some 60 universities badger authorities for permission to enter the normally forbidden "red zone" around the foot of the mountain. Some of those denied access have accused the Forest Service and the U.S.G.S. of conspiring to corner data from the mountain, using bureaucratic red tape to keep out competing researchers. One regulation: each investigating team must have a radio operator, a function that is being performed by local hams. But now there are not enough to go around, and scientists must wait days to get one. Moans Portland State's Allen, head of the screening committee: "Dozens and dozens of scientists have been turned away, and we've lost invaluable information during the summer." The hassle has proved too much for Allen. He is stepping down from the committee next week.

Never in history has a volcano exploded with such force before such an array of sophisticated monitoring instruments. The gear even includes a space satellite to measure particulate matter blown into the stratosphere. Yet in spite of all the detection capability, scientists have come away from the mountain basically with confirmations of what they already knew-- primarily from observing volcanoes in Hawaii--rather than with any new and startling insights. Says Donald Peterson, the U.S.G.S scientist in charge on the scene: "Everything the mountain has done has been within the realm of our expectations."

Well, not quite. The force of the blast and its timing surprised scientists. They are still not much closer to predicting when a volcano of the St. Helens type will blow; scientists have had much better luck with volcanoes in Hawaii. But the effort has hardly been a waste of time. Says U.S.G.S. Geologist Robert Christiansen: "It has taught us that volcanic hazards are real in the U.S." More probing will be done in November at a NASA conference about the atmospheric and climatic effects of Mount St. Helens, with a view to decoding whatever messages the volcano sent on that fateful May day when the earth opened and the forces of creation were furiously unleashed.

--By John S. DeMott.

Reported by Paul A. Witteman/San Francisco and Jerry Hannifin/Washington

With reporting by Paul A. Witteman/San Francisco, Jerry Hannifin/Washington

This file is automatically generated by a robot program, so viewer discretion is required.