Sparrows Point was less than a mile from Christine Gangi's home where she lived for 13 years, battling the kish that blew into her pool, yard and home. She says the steel mill ruined her life. (Jamie Smith Hopkins/Baltimore Sun video)

When the Sparrows Point steel mill closed, Deborah S. Barkley felt sorry for the laid-off workers — she didn't want that to happen. But she knew her life would get better.

For 20 years, she's lived less than a mile from the Baltimore County plant. Until the facility shut down last summer, she said, silvery black grit and dust from steelmaking — known as kish — regularly blew in or rained down onto her family's yard, was tracked onto the carpets and corroded the exterior of the house.

Keeping her property clean was a constant battle. She stopped having cookouts. She tore out the pool she'd spent $10,000 on for her three kids. And though the state described it as more nuisance and respiratory irritant than health risk, she worried about whether the "silver rain" was harming her children. All three suffer from year-round allergies.

"It invaded our lives," said Barkley, 59. "It just was endless."

Pervasive pollution is steelmaking's unfortunate legacy in and around Sparrows Point. How much remains in the ground and the water is unknown. The mill's various operators have been under orders to clean up the site since 1997.

With steelmaking done, the kish is now gone. But it was the most visible form of that pollution for nearby communities, and anxiety about it will linger long after the mill's final pieces are carted off. That's because little research has been done on the byproduct's health effects, and what exists is unsettling.

Kish, produced from molten iron, is primarily graphite and iron oxides, with a mishmash of other steelmaking ingredients — from aluminum to chromium.

A 2000 Environmental Protection Agency report on Sparrows Point kish confirmed it was getting into residential areas, including a significant amount small enough to inhale. The kish's "concentrations of chromium and zinc suggested a potential toxicity concern for human health and the environment," the report added.

Questions raised by the Chesapeake Bay Foundation — the mill sits near the bay, nearly surrounded by water — prompted the Maryland Department of the Environment to take another look at the EPA report years later. In 2010, the agency asked the EPA to conduct more particulate sampling in Sparrows Point to evaluate potential health risks.

Roy Seneca, an EPA spokesman, said his agency hadn't begun the project before the mill shutdown last year made it impossible. No kish, nothing to measure.

That means the health risk suggested in the EPA report can't be quantified, said Dr. Jed Miller, the state environmental agency's health adviser. He said exposures to some elements that may be found in kish, such as manganese, are only linked with health problems above certain levels.

Complicating matters, he said, is that he could find nothing about kish exposure in the medical literature.

"It's one of those things that's uncertain," Miller said.

Troubling questions without full answers is a theme for Sparrows Point pollution, said Kim Coble, vice president of environmental protection and restoration at the Chesapeake Bay Foundation.

Setting aside kish, a variety of "very hazardous" chemicals remain in the soil and waterways from more than a century of steelmaking, she said. Much, she added, is still unknown about the extent and effects of the pollution.

"The type of industry that was there used and discharged very toxic kind of chemicals, including heavy metals and what are called PAHs," said Coble, referring to polycyclic aromatic hydrocarbons such as naphthalene and anthracene. "These are cancer-causing chemicals that are very concerning to public health officials."

Old cleanup pledge

In 1997, after years of complaints, then-owner Bethlehem Steel agreed to cleanup efforts at Sparrows Point that the company said could cost $50 million. That consent decree with the EPA and the Maryland Department of the Environment settled lawsuits newly filed by both agencies.

The agreement required the company to look for hazardous wastes on the site, clean contamination if it posed an immediate health threat, reduce — though not stop — kish releases, and make other changes.

Since then, no immediate threats to health were found, the state says. Maryland's environmental agency said Bethlehem Steel and subsequent mill operators cleaned or contained most of the contamination.