The 72-year-old Woolsey didn't connect the incinerator to his own life until a year ago, when he began stumbling while on vacation in Arizona with his wife. He was falling down, Woolsey said recently from his daughter's Layton home. Not acting himself. "Pretty soon, I didn't know anything."

A CAT scan showed a shadow on his brain. Two days later, doctors removed 90 percent of a brain tumor as big as an apple.

The cancer has caused Woolsey, his family and other residents to look to the incinerator and ask questions.

Four times in the past six years the plant has failed state-mandated tests of dioxin emissions. The incinerator currently has no way to regulate dioxin. The plant repeatedly appeals its failed tests, and it has asked the state to double the amount of dioxin it is allowed to release. The state Air Quality Board has not ruled on this request.

These repeated emission failures and residents' perception the plant is dragging its feet about addressing the problem have led to a grass-roots effort to link the incinerator to gliosarcoma, the type of brain cancer Woolsey has. The idea is that dioxin travels into the ground and air nearby — it gets absorbed into the soil, inhaled by residents and eaten by animals that graze in Davis County.

"We've had a garden and we've been eating out of it for 13 years, so I don't know . . . " Woolsey said.

Woolsey's daughter, Louise Love of Layton, has done her own research. "I have no proof right now. But how am I going to get any until I get someone out here to do a study?"

A hand-drawn map shows 30 cases of gliosarcoma Love has tracked down among friends, neighbors and residents within a three-mile radius of the incinerator.

Karen Keller, epidemiologist for the State Department of Health, said 30 gliosarcoma diagnoses would be extremely high for such an area, but her office hasn't been able to verify all 30 cases. Without verification — from individual doctors who are reluctant to divulge patients' histories or pin cancers and problems on a specific source — Keller's hands are tied.

Woolsey's physician, Dr. Deborah T. Blumenthal, director of the division of neuro-oncology and assistant professor of neurology at the Huntsman Cancer Institute, says this case does not illustrate a connection as strong as that between smoking and certain types of lung cancer.

She has seen Love's list of 30 people with brain tumors and knows Woolsey as well as two other residents who died of "GBM" or glioblastoma. She has not confirmed the other cases of gliosarcoma, a rare type of GBM.

She said she is concerned about the list and says it is appropriate to encourage a cancer cluster study. "From what I could find out about dioxin, I didn't see a link with brain cancers," Blumenthal said. She did see lab evidence that chronic dioxin exposure in rats causes lung lesions, ovarian tumors and liver tumors.