`IT'S the thrill of a lifetime.'' Those were the words of Bob Luther of Albany, N.Y., after he recently trudged over snow, rock, and volcanic ash up the south face of Mt. St. Helens, 40 miles north of here, to see, from the crater's rim, the destruction and recovery from its 1980 eruption. Mr. Luther had first viewed the volcano from a distance two months earlier during a family trip to the Northwest and vowed to return for a closer look.
``I did it,'' he said.
So did 13-year-old Josh Sutton from Aloha, Ore., who made the climb with a junior high school friend and then marveled, ``I didn't expect the crater to be so big.''
Luther and Sutton were two of 100 climbers and thousands of drivers coming daily to the Mt. St. Helens National Volcanic Monument this summer to view the vast changes. Climbers must obtain permits, available only since April.
A decade earlier a symmetrically rounded, snowcapped dome - sometimes called the ``Mt. Fuji of the West'' - had risen 9,677 feet above a landscape of conifers and lakes.
All that was altered dramatically on May 18, 1980, when the top 1,300 feet of the mountain blew off in a catastrophic eruption and avalanche that turned more than 150 square miles of the subalpine garden into a wasteland several shades of gray.
Today, climbers can look down into the gutted mountain and see steam rising from several points in a rocky lava dome on the floor of the crater and hear rock tumbling from crumbling crater walls. To the north, the grays have turned to browns, and splotches of green are becoming visible again.
Indeed, on closer inspection of the area affected by the eruption, the biological recovery has been greater than even the experts anticipated.
``What was initially surprising,'' says Peter Frenzen, a forest ecologist at the University of Washington who has been studying the mountain's biological recovery for the United States Forest Service, ``was that there was so much surviving in that landscape.''
In fact, Mr. Frenzen and his research associates found that buried beneath protective snowbanks and the fall of volcanic ash were fully 90 percent (more than 230) of the species of plants that had existed before the eruption.
``The eruption occurred in the early spring, when a lot of the plants were in a dormant condition,'' says Frenzen. ``They had dormant bulbs or dormant root tissue beneath the soil that were not burned off or blasted off by the eruption. With the rains, they just sprouted up through the ash deposits where those deposits were thin enough.''
Even some of the animals - such as gophers and ants - endured the blast, because they were asleep underground at the time it occurred.
``The most remarkable thing is that some of the areas that were hardest hit are recovering at a very fast rate,'' Frenzen observes.
He cites as an example the area directly in front of the north side of the crater, which received the heaviest scouring from superheated volcanic gases followed by the deepest burial from the massive debris avalanche and lava flow.
``Even there, life is returning,'' says Frenzen, ``particularly around areas where steam percolated up through the deposits from ground water that seeps through the hot rocks underneath. As the steam comes out and condenses, there are these very nicely watered pumice areas where seeds blowing in take root.'' Perhaps 20 species of plant life are involved, he adds, including various firs and hemlock.
``As those trees grow up, they'll be producing cones within 20 years,'' says Frenzen. ``Within 50 years, we'd expect to see scattered stands of trees and within 100 years, continuous forest development.''
While officials are maintaining a ``hands off'' attitude toward recovery in the monument area, vigorous public and private programs have been undertaken to replant trees in areas next to the monument's borders.
The Weyerhaeuser Company, for example, has planted 17 million trees, many of which have already grown above the heads of its foresters. ``Managed forests can grow much more quickly than unmanaged,'' says Joseph E. Means, a research forester in Corvallis, Ore., ``because roots of seedlings can be placed by man directly beneath the tefra [volcanic ash], in nutrient-rich buried soil.''
Ironically, for climbers who want to see the volcano's effects, evidence of the devastation is disappearing as the mountain greenery returns.
``It's changing fast,'' Frenzen warns. ``If people want to see the destruction, they'd better hurry. Of course the biological story will be continuing, and the recovery has a unique beauty all its own.''
Mt. St. Helens National Monument, Rte. 1, Box 369, Amboy, WA 98601.