LOUISVILLE, Ky. (WDRB) -- The operators of a Rubbertown plant with a history of air quality violations now want the city to relax some pollution rules -- but on Wednesday, neighbors fired back, warning decision makers to err on the side of caution.

Barbara Boyd could go on and on about her love for living on Brewster Avenue.

"I like sitting on my front porch," Boyd said. "I like being in my yard. I like being in the sun and wind and seeing the trees and birds."

But after 22 years there, she's also very clear about the drawbacks.

"The worst thing about my neighborhood is Rubbertown," she said.

Boyd's complaint was echoed by dozens of residents Wednesday during a public hearing on American Synthetic Rubber Company.

"You can't be asking the people to suck up more of this so they can make money," demanded one resident.

The company wants the city to amend certain provisions in the Strategic Toxic Air Reduction program known as STAR.

You can't see the problem, but it's there: Butadiene, an invisible chemical used in the company's tire part and aerospace production. Leaks in valves, connectors and piping spark consistent violations for the Rubbertown plant, including a $27,000 fine in 2014.

"We replaced all the receptor disks in the Butadiene service," said Guillaume Coiraton, the plant manager.

ASRC asked the city's air pollution regulators to adjust its release goal from about 2,600 pounds a year to about 6,700 pounds a year.

"It is a complete slap in the face of the residents who live in these neighborhoods," said Jessica Green, the Louisville Metro Council member who represents the area. "The residents' lives are more important than a modification for a company."

One-by-one, loud and consistent "nos" could be heard from neighbors, including Boyd.

"Rubbertown, I believe, has affected me personally," Boyd said. "I had a surgery recently for thyroid cancer -- and cancer does not run in my family."

Butadiene is a known carcinogen and is thought to cause respiratory problems.

The company says it has implemented best practices, like improved monitoring and faster repairs, taking Butadiene leaks from 103,000 pounds a year in 2003 to fewer than 4,000 in 2016

"We really strive for solid transparency and cooperation with the public," said Coiraton.

It's ultimately looking for an obtainable goal to stay out of violation.

"It is a very complicated situation, and we want to be very thoughtful and analytical in this process," Keith Talley, Sr., director of Louisville's Air Pollution Control District.

Decision makers provided no answers on Wednesday. Boyd says she's not giving up the fight.

"I want to see it fail," Boyd said.

ASRC told regulators it's going to amend its request, backing down off that 6,700 pound release goal -- but that proposal has not been submitted.

A second public hearing is set for 6 p.m., May 17, at the Edison Center at the corner of S. 7th Street and W. Ormsby Avenue.

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