Archaeologists are toiling side by side with construction workers on the Alaskan Way Viaduct and Highway 520 projects.

They're collecting broken bottles, peach pits and peanut shells. But instead of litter sticks and garbage bags, they are wielding trowels and shovels, and paying $342,000 for a space to preserve the junk.

Because one man's trash is another man's ... really, really old trash.

"What archaeology is, is people's garbage," Washington State Department of Transportation cultural-resources specialist Kevin Bartoy said. "But what that garbage is to archeologists is little bits of data."

Though they won't find "the gold idol," archeologists are piecing together a picture of 19th- and 20th-century Seattle society that is not well recorded, Bartoy said....