Here in the redrock desert of southern Utah, it is literally an earthshaking reality.

Oil and gas exploration is going on in the form of seismic tests, conducted with what are called thumper trucks, in sensitive wildlands adjacent to Arches and Canyonlands National Parks.

Last Sunday, with a group of friends concerned about the fate of this landscape, one of America's most treasured, I witnessed the destructive power of the thumper trucks on the fragile desert.

We had a Bureau of Land Management map showing the territory designated for exploration and drilling under the Bush energy plan. This pristine country of sandstone formations, pinyon and juniper forests, and fragile alkaline desert is one of the proposed preserves in the Redrock Wilderness bill now before Congress, which would protect these lands from new leases for oil drilling and exploration.

Lines drawn on the map marked the physical corridors where four large trucks would crawl cross-country, tamping the desert for clues as to where oil might be found. As we set out to look for the trucks, our task was simplified by a helicopter carrying what appeared to be an enormous doughnut. It was a tire. We watched where it was dropped and hiked to the work site. A thumper truck was lodged in the steep banks of a wash, its huge rear left tire having been torn off by an unseen boulder. Parked nearby was a truck in which WesternGeco, the company contracted to do this preliminary work, was recording the seismic information.

Three other thumper trucks were at work about half a mile ahead. Behind them was pulverized earth: a swath of beaten down and broken junipers, blackbrush, rabbitbrush, squawbush and cliffrose. The delicate desert crust that holds the red sand in place from wind and erosion, known as cryptobiotic soil, was obliterated. Replacing it, in effect, was a newly crushed road.

In January Jayne Belnap, a United States Geological Survey expert on soil damage, submitted an official comment letter to the Bureau of Land Management about the fragility of desert crusts, warning it could take from 50 to 300 years for the dry soil to recover from the damage incurred by heavy equipment.

Up close, the thumper trucks creeping across the desert looked like gigantic insects, gnawing and clawing across the rugged terrain. At the designated stops, each truck in the convoy lowered a steel plate onto the desert, clamped tight and then sent a jolt of seismic waves below to record density.

The ground went into a seizure. Sand flew and smoke obscured the horizon where Skyline Arch and Sand Dune Arch - the Windows section of Arches National Park - stand.

When the steel plate lifted, the once supple red sand had turned to concrete.

We were only a few miles from Delicate Arch, where a few weeks ago a Ute elder uttered prayers and passed the Winter Olympics torch to his granddaughter in the name of goodwill and peace.

The trucks moved forward, heading straight for a spring where 100-year-old cottonwood trees provided a rare canopy of shade.

We ran ahead, not believing the trucks would force a road into this fragile desert oasis, but they did, gunning the gas, breaking down stands of squawbush and willows and ripping right on through the cottonwood shoots. There was nothing we could do but watch. This was America's new energy plan, translated into action.

Terry Tempest Williams is author of "Red: Passion and Patience in the Desert

Copyright © 2002 the International Herald Tribune

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