SPRINGFIELD &

A shovelful at a time, Chris Ruiz sifts dirt from an unmarked grave through a one-eighth-inch screen. There are bones there. But whose?

He and anthropologists from the University of Oregon Museum of Natural and Cultural History are piecing together clues from the grave site plus land titles and other records after a backhoe operator turned up an unmarked grave on the construction site of Sacred Heart Medical Center at RiverBend.

State and federal laws protect anthropological sites for the valuable historical data they may contain, said Guy Tasa, who heads the project.

A few things are known.

The skeleton is male and probably was the grave's only occupant, although that is not yet certain.

A row of old-fashioned square-cut nails found alongside the skeleton indicates the burial probably happened before the nails went out of general use around 1920.

A small clothing buckle and a Prosser-style button common before 1920 have turned up.

Archaeologists brushed dirt from the bones and removed them, finding upholstery tacks among remnants of the coffin's wood bottom.

"We've definitely moved up from just a plain pine box," Tasa said.

The site was once owned by William Stevens, an early pioneer settler in what became Springfield. By the 1850s it was "a happening place," with scattered homesteads and regular commerce, Tasa said.

The land changed hands many times, so old land records may help, he said.

Tasa's teams usually works for the Oregon Department of Transportation and deal with prehistoric Indian burials with cultural and spiritual values to the tribes.

But the grave at RiverBend may clarify information about pioneer life not made clear in journals and historical documents.

"Skeletons can tell us a lot about the course of a life, not just the cause of a death," Tasa said. "There are a lot of things we can learn. We don't have a real great picture of pioneer life in Oregon."

Bones can reveal diseases, such as tuberculosis. They can tell about a person's injuries. And teeth can reveal much about a person's diet, he said. His specialty is physical anthropology a blend of biology and anthropology that makes him an expert on bones.

"Ultimately, our goal is to try to figure out who this person is," he said.

Then the search will shift to finding relatives to determine what they wish to do with the remains. State law leaves PeaceHealth, the landowner, holding the tab for the investigation and the eventual reburial.

But Ruiz said that will happen only after the meticulous sifting dirt, collecting and analyzing clues and searching state and local archives for ownership documents and other records.

A clue could be a shard of glass, a button or a chip from a porcelain dish. Ruiz will examine those clues, compare them to the museum's large collection of historic materials and use reference books to determine dates.

"Patience is a big thing. Just rigorous technique. You have to know what you're doing and do it with precision," said Ruiz, who discovered his passion for historical anthropology while growing up in New Mexico, where his parents took him to anthropological sites.

"The mystery of it drew me in to pursue it as a career," he said. "I developed a love for it."