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Blown To Kingdome Come

With a rumble that reverberated through the feet of thousands of sports fans gathered downtown for one last hurrah early Sunday, the great gray roof of Seattle's Kingdome collapsed in a controlled implosion.

It took less than 20 seconds for 5,800 gelatin dynamite-filled holes to reduce the house of football's Steve Largent and baseball's two Ken Griffeys to rubble.

The implosion sent a huge cloud of dust across downtown Seattle. Safety crews immediately went to work checking buildings and bridges to make sure they hadn't been damaged by the blast.

When the dust cleared, you could see the remains of the stadium creating a radial pattern from what once had been the dome's center.

The implosion of the 24-year-old Kingdome, dubbed the mushroom, the concrete cupcake and other less charitable terms over the years clears the way for a new $430 million football stadium.

The ribbed roof dome has been a city landmark since its 1976 completion at a cost of $67 million. The Seahawks made their debut in the Kingdome that year, and baseball's Mariners arrived a year later.

In the Rainy City, the dome was a necessity, but fans complained the cold concrete stadium was too small for football and not intimate enough for baseball. What's more, it leaked, and in 1994, four ceiling tiles crashed into the stands just hours before a Mariners' game.

But smallness and concrete had advantages, too. The noise level was immense, and as Ken Griffey Jr. proved, it was a home-run hitter's paradise.

Sunday's implosion had little impact on the Mariners. The team moved into the new $517 million Safeco Field last summer, complete with real grass and a retractable roof. As for the Seahawks, their new stadium will be ready in about two years. Until then, they'll share the University of Washington stadium.

The cheers of spectators notwithstanding, not everybody wants to see the stadium come down -- former governor John Spellman, for example. Spellman was King County Executive when the dome was built and he is among those who wanted to see it stay.

After working for years to build a stadium that would draw professional sports to Seattle, Spellman thinks demolishing the dome now is "disgusting."

Another who shares Spellman's feelings is engineer Jack Christiansen, who designed the building. Christiansen says he feels sick at the thought of the dome coming down. As he put it, the destruction is "the dumbest thing I've ever heard of in my life."

But scientists see an opportunity here. The so-called Seattle Fault runs right under the Kingdome and stretches from Bremerton and Bainbridge Island through Seattle to Issaquah. Scientists will use the implosion to create a three-dimensional map of seismic risk, an invaluable guide for when the Big One strikes, they say.

"This is going to give us a much more detailed ground-shaking map for the area," said Craig Weaver, senior scientist for the U.S. Geological Survey in Seattle. The Seattle Fault is believed capable of producing a magnitude 7 earthquake. The 1995 quake in Kobe, Japan that killed 6,500 people and caused billions of dollars in damage was magnitude 7.2.

Hours before the Kingdome implosion, earthquake scientists detonated explosions about 100 feet deep at four corners of metropolitan Seattle. They aim to use these explosions, under Magnuson, Discovery, Seward and Lincoln parks, to calibrate their measurements of the seismic wave that the destruction of the Kingdome will produce.

Some 200 seismic detectors are being placed throughout greater Seattle to record both induced seismic events.

"Our goal is to make detailed maps of Seattle that can describe, block by block, the amount of ground motion shaking expected during an earthquake," said Art Frankel, a USGS scientist from Golden, Colo. "By recording these timed seismic waves, we can get there."

A similar seismic recording test last September surprised both residents and scientists. Some residents believed the induced event was a real quake.

"We weren't expecting such a strong response," Weaver said. "We got a big ground roll."

That means the ground in the Seattle area is a lot more prone to shaking during an earthquake than was expected, with parts of West Seattle and the area north of the Ship Canal previously thought to be relatively stable especially vulnerable.

Despite the magnitude of the risk, it's doubtful the Kingdome implosion will cause a major quake, said Bill Steele at the University of Washington seismic lab.

"We have quakes bigger than what we'll get from the Kingdome implosion every week and they don't set off the Seattle Fault," he said.

The scientific community only became aware of the region's history of massive quakes a decade ago. Scientists say the Kingdome study is needed to get a better handle on the Seattle Fault, which is large enough to devastate the region. It apparently did just that 1,100 years ago, when it sent tsunamis rolling back and forth across the Sound and Lake Washington, caused massive landslides and sent coastal forests into the water.

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