Officials at the chemical plant in St. John the Baptist Parish that has come under scrutiny for emissions of a chemical called chloroprene report they have finished installing equipment that should cut the plant's emissions significantly.
The company, Denka Performance Elastomer, said that as of early this month it had completed a four-stage retrofitting at a cost of almost $30 million, nearly twice what the LaPlace plant said it intended to spend on the project when it was first announced in 2016.
The goal is to reduce chloroprene emissions — deemed a "likely carcinogen" by the U.S. Environmental Protection Agency — by 85 percent.
The strategy was mandated in a voluntary consent agreement signed last January by the company and the Louisiana Department of Environmental Quality.
On Friday, company spokesman Jim Harris said Denka doesn't have enough data yet to say whether the work will meet the goal, but he cited a "downward trend" in emissions.
"You occasionally have anomalies, but the trend is definitely on a downward turn," Harris said, referring to a graph charting the trajectory of monthly average chloroprene emissions between August 2016 and December 2017.
"Our voluntary emissions reduction plan represents Denka's commitment to our community," said Jorge Lavastida, Denka's plant manager.
Local environmentalists, however, have been saying for months that Denka's plan to reduce emissions is inadequate, even if it meets the goal of an 85 percent reduction.
Wilma Subra, a scientist with the Louisiana Environmental Action Network, said the latest data showing the area's ambient chloroprene levels seem to confirm that Denka's reduction strategy won't be enough to satisfy a public health recommendation issued by the EPA.
"From the perspective of the community, we’re still very concerned about the exposure of that chemical," Subra said.
She added that residents constantly complain of feeling ill, reporting symptoms ranging from respiratory issues to dizziness and nausea.
The plant, which uses chloroprene to make the synthetic rubber neoprene, has been operating for decades, though it was not acquired by Denka until 2015. That was the same year the EPA released a study showing local residents were at a heightened risk of cancer because of the plant's emissions.
The company's own data show emissions have been declining over roughly the past year and a half, though with big spikes during certain months.
Average monthly emissions from August 2016 through December 2017 ranged anywhere from about 1 microgram of chloroprene per cubic meter of air to nearly 11 micrograms per cubic meter.
Those numbers fall far below the 857 micrograms per cubic meter currently allowed in Louisiana, but they are anywhere from 5 to 55 times what the EPA says could be dangerous over prolonged periods of exposure.
As state experts continue to study the chemical, plant officials are waiting to see what the data show after installation of a regenerative thermal oxidizer, which uses heat to destroy pollutants.
That was the final and most important piece of equipment in Denka's multi-step plan to dramatically reduce the amount of chloroprene released into the air.
Once the data are in, state and federal officials will decide whether they should force the company to lower emissions of the chemical still further, according to Chuck Brown, secretary of the Louisiana DEQ.
"Whatever we end up doing, it will be protective of human health and the environment," Brown said recently, adding that the limit must also be "enforceable" on industry.