No easy answers in chlorine leak

Rock Hill officials spent five hours huddling with a parts supplier and inspecting a cracked pump at the city's water treatment plant on Monday night.

But they didn't get much closer to figuring out more about what caused a chlorine gas leak that forced the evacuation of more than 500 homes.

Replacing the pump will be simple; understanding why it cracked may take several weeks, said Utilities Director Jimmy Bagley.

"The pump's only $300," he said. "That's not a big deal. My issue is I don't want it to happen again. I don't know if something happened to make the pump fail."

A chlorine dioxide leak Monday morning prompted a nine-hour ordeal that forced people from their homes, kept businesses from opening and triggered the shutdown of two heavily traveled roads.

No one was put in immediate danger, but during a lengthy meeting with the equipment manufacturer and contractor, Bagley said city officials stressed the need to find answers.

"They definitely know the urgency," he said. "We've shared that with them. They understand the problem."

Because the pump is out of service, the city is using a backup option to treat the water: Adding pure chlorine instead of chlorine dioxide. It's a more expensive process, but still safe, officials say.

The pipe is housed in a new section of the plant that had been in operation for five weeks.

"We're back to operating the plant the way we did before," said Nick Stegall, the city's public services administrator. "The chlorine dioxide was a little better option, but it's something we can do without for a while."

The leak lasted for about 45 minutes, resulting in less than a pound of chlorine escaping. Chlorine, added to water as a disinfectant, can cause irritation of the eyes, throat and lungs if inhaled.

Not knowing whether any gas had seeped outside, responders decided to evacuate some 1,500 neighbors, shut down parts of Cherry and Mount Gallant roads and Eden Terrace and keep area employees from driving to their workplaces.

By 1:20 p.m., inspectors determined the leak no longer posed a threat because it was contained to the building.

York County's top emergency management official defended the call for evacuations, saying residents needed to be out before the threat materialized, not after.

"Had we left them in place, we could not have relocated them safely," said Cotton Howell, director of emergency management. "There weren't any real options. I would not have wanted to sit here and say, 'We didn't go as far as we could have,' and someone was injured."

The plant, built in 1950, recently underwent the most extensive renovations in its history. Bigger pipes and a third 1 million gallon storage tank were installed to increase capacity.

Rock Hill sells water to Fort Mill, which in turn sells water to York County. The city of York recently joined the customer list.