CHAPEL HILL - Nancy Holt grew alarmed four and a half years ago when her grandson and great nephew got staph infections after wading in the creeks behind her house.

She blames the substance that's sprayed on farmland near her western Orange County home -- a liquidy mixture left over after processing at wastewater treatment plants. It's called biosolids by government officials and sewage sludge by those who live near the fields where it's spread.

Holt and her husband, Bruce, let the brush grow and stacked fallen tree limbs to block the paths to Tom's Creek and the McDaniel Branch. The creeks flow in a V-shape behind their home, then down into the Cane Creek Reservoir -- a source of drinking water for Chapel Hill and Carrboro.

Holt can list one unusual medical calamity after another on her road -- neighbors with antibiotic-resistant staph infections, children with sinus infections that last all summer. Holt herself is on steroids to keep the arteries in her brain from swelling, an inflammation she says her doctors speculate could be triggered by chemicals sprayed a few hundred yards from her front door.

Holt, a retired nurse and health care administrator, has persuaded Orange County to look into the problems in her Bradshaw Quarry Road community.

The Orange County Board of Commissioners will spend $10,000 for a study in collaboration with two environmental health specialists from the UNC School of Public Health who will test surface water and air quality before and after biosolid applications.

The county has performed tests in the community before without drawing conclusions, said Tom Konsler, the county's environmental health director.

At that time, no fecal coliform was detected, but eight wells had total coliform, which is not harmful but can signal that a well is vulnerable to contamination, Konsler said.

Konsler recalled that his department worked with each well owner on making repairs or setting up filtration systems.

Over this past summer, Holt said, she had her well tested, and fecal coliform was found. Then she learned that two of her neighbors had recently found the same.

Wells are tricky to test because, depending on how they're built, it can take a long time for substances to creep in, said Rosemary Summers, Orange County's health director. That's why the new study will focus on surface water and stream run-off, which are affected more quickly.

Konsler hopes the study also surveys neighbors to determine whether there is a higher-than-average occurrence of illnesses.

Barry Jacobs, vice-chairman of the Board of Commissioners, said the study is timely as the board considers letting the Orange Water and Sewer Authority apply biosolids to county park land. OWASA, which serves Chapel Hill and Carrboro, also is considering applying biosolids in its watersheds, which it has avoided doing in the past.

A 'first step'

Counties have little control over where biosolids are spread. Each water and sewer agency applies for state permits, and arranges with landowners to spread the treated waste, which serves as free fertilizer for the farmers.

"Presumably they'll bring some research to bear that will be applicable in various circumstances, whether it's Burlington Class B biosolids or OWASA class A biosolids," Jacobs said.

In Burlington, Water and Sewer Operations Manager Eric Davis said the study could alleviate the community's concerns.

"I'm glad to see there's going to be some testing done. Maybe that will help -- help with some of the concerns about it," Davis said.

Holt doesn't expect the study to make her feel better.

"This first step, this small study, can open a door," Holt said. "It's only going to be a little tiny piece. But it's either going to be, 'These people are nuts, it's all in their heads, it has nothing to do with anything.' Or, 'There may be a real problem here.' "