The reason most residents of Picher won't be able to rebuild their homes following a massive tornado is plainly visible from most parts of town. Massive piles of lead and zinc mining waste - known as chat piles - tower above the landscape in far northeastern Oklahoma. The Environmental Protection Agency long ago declared the area a Superfund site, and many residents had already accepted state or federal buyout offers as the town's population dwindled to about 800. "You can look at the chat piles and see that a lot of the material has blown off," said John Sparkman, the executive director of the Picher Housing Authority. "We went up on a chat pile an hour and a half after the tornado hit, and you could see dust blowing fine material all over the place from that vantage point."

A local fire official maintains that any residual mine waste stirred up by Saturday's storm is not a concern for residents. Still, EPA scientists arrived in Picher on Monday to assess the environmental impact of the tornado that killed six people in the town. Sixteen others died in Missouri and Georgia during the tornado outbreak.

The EPA set up a mobile command center and will try to determine how much lead-contaminated dust remains in the air. EPA spokeswoman Tressa Tillman said the air tests began Monday and soil tests will start Tuesday.

Based on a visual inspection Monday by EPA scientists, "It does look like residential areas do have chat," she said.

Miles Tolbert, Oklahoma's secretary of the environment, said the expectation is that there is no immediate public health hazard to the people now working in the devastated area, but more testing is needed.

Long-term exposure to lead dust poses a health risk, particularly to young children. It is this risk, plus the danger of land caving in to old mining tunnels, that makes Picher a national Superfund site.

Picher Fire Chief Jeff Reeves said the chat is, at most, a nuisance.

"These people live here every day," Reeves said. "It's no more a concern now than it was" before the storm.

Also arriving Monday were officials from the Federal Emergency Management Agency, who began the process of determining whether the town's residents qualify for federal assistance. Oklahoma Department of Emergency Management spokeswoman Michelann Ooten said FEMA (web|news) had determined 101 homes in Picher had been destroyed.

FEMA spokesman Earl Armstrong said Picher's status as a Superfund site won't affect whether federal assistance to individuals and businesses is approved.

"We're looking at it like any other town that got hit by a tornado," Armstrong said.

But there remains some question about how such money could be used, since federal officials aren't likely to allow residents to rebuild on a Superfund site. Oklahoma Emergency Management Director Albert Ashwood has said that if individual assistance is granted, it will likely be for residents to relocate.

The owners of some of the homes that were destroyed were waiting for assessments by or negotiating buyout offers with the federal government. Gov. Brad Henry and U.S. Sen. Jim Inhofe, R-Okla., both said Sunday that program will continue.

Homeowner Ralph Morris, who had rejected a previous buyout offer, took a philosophical approach about it all.

"The last year, we've been trying to ... make things right with the buyout. It seems like the government is hurting us more than helping us at this point," Morris said.

"There's a lot of good people here. It's going to be rough leaving here. Maybe this is God's way of saying it's time to give up the fight."