A six-member jury, after eight hours of deliberation, on Friday night found for DuPont in a failed whistleblower lawsuit, deciding there was not enough evidence that leaks from its Burnside plant constituted a substantial risk to the public and required reporting to EPA.

Because of the verdict, plaintiff Jeffrey M. Simoneaux, of Prairieville, is not eligible to collect a share of any fines that the U.S. Environmental Protection Agency might levy.

He also lost his claim that DuPont retaliated against him and created a work environment so hostile that he had to leave. He was not awarded back pay or other damages either.

The jury decision was unanimous. The jurors began deliberations shortly after noon Friday and returned with the verdict at 8:30 p.m. They sat through a nearly two-week trial in U.S. District Court in Baton Rouge in which the plaintiffs put on videos and some worker testimony of the leaking plant and a tape recording of plant manager Tom Miller telling workers not to report the leaks in May 2012. But DuPont experts questioned whether leaks constituted an actual hazard while company attorneys questioned Simoneaux’s motives.

He had alleged DuPont hid three years’ worth of leaks from the Ascension Parish plant along the Mississippi River to avoid fines from EPA.

Simoneaux claims DuPont had a duty under the federal Toxic Substance Control Act to report the leaks of toxic sulfur dioxide, carcinogenic sulfur trioxide and a sulfuric acid mist.

DuPont’s attorneys have not disputed that its equipment — which essentially was the heart of a plant designed to recycle spent acids and had been upgraded after a 2009 consent decree with EPA over air emissions — had leaking cracks. But the company contended the leaks were contained with a vacuum hose system, so DuPont did not have the obligation to report them under TSCA. The company is now preparing to replace the damaged equipment at a cost of $17.2 million.

Attorneys for DuPont and the plant manager, Miller, would not comment after the verdict but referred a reporter to a corporate spokesman.

“We are pleased with today’s decision and the fact that the jury concurred with our position,” DuPont spokesman Daniel Turner said.

Plaintiff’s attorney Jane Barney said she and Simoneaux’s other attorneys are proud of what their client did to speak up about the safety concerns at the plant.

“And, hopefully, he paved the way for others to do the same,” said Barney, who represents two other people — one a former and one a current DuPont workers — in discrimination claims against the company. They testified on Simoneaux’s behalf.

In closing arguments Friday morning, attorneys left jurors with two narratives to chew on: that of an angry employee with an ax to grind who trumped up an otherwise safe situation or that of a global chemical giant trying to hide that it was running a faulty plant with makeshift repairs despite the risks.

But DuPont’s attorneys countered that Simoneaux had an agenda against his longtime employer after one of his friends and co-workers was terminated in late 2011. That’s when he began collecting evidence about the leaks for a future lawsuit even though the company had them safely contained, the attorneys said.

Parts of the trial centered on expert testimony about whether these leaks constituted an environmental and health risk and delved into the complicated methods of calculating the size and content of gas releases, which are dependent on a number of factors and can vary based on where a leak is located.

In closing Friday, DuPont attorney Monique Weiner underscored her statement at the beginning of the trial that Simoneaux would have no evidence that state and federal regulators found major problems with leaks or that the plaintiffs would have evidence showing leaking gas was at dangerous concentrations.

“That’s what I was talking about when I said there will be zero evidence,” Weiner said.

She also reminded jurors of DuPont’s own testing and calculations showing the leaks were minimal and of testimony from contractors at the plant who felt they were safe.

Weiner also accused Simoneaux of trying to have it both ways, on the one hand claiming the leaks were dangerous to workers and surrounding plants and schools but taking actions that seemed to belie such fears.

She reminded them of Simoneaux’s cellphone records showing he was talking to former co-workers and his lawyer, Barney, when he allegedly saw major leaks on Oct. 27, 2013, and even drove to get a camera from her in Baton Rouge before he called 911 two hours later. Simoneaux did not wait for the Ascension Parish Sheriff’s Office to show up, Weiner said.

Barney countered that DuPont’s leak calculations were wrong or greatly undercut the leaks’ size. Barney also contended the TSCA statute is aimed at prevention and does not require certain dosage levels be hit before reporting is necessary.

Barney pointed jurors to the internal and external videos of leaking gas and testimony about the ongoing leaks that they heard from Simoneaux, former co-workers and one of DuPont’s own engineers once assigned to the Burnside plant.

The engineer, Luis Chu, testified that the system of plastic vacuum pipes attached with duct tape and rope to control the leaks was intended to be a temporary, incomplete fix until repairs could be made.

Barney told jurors that Chu, who is based out of state but visited the plant periodically, testified he was disappointed to learn the plastic piping had been used for so long. The piping was subject to unexpected failures from the leaking gas’s corrosive qualities.

Had Simoneaux prevailed, he could have recovered up to 30 percent of possible $37,500 fines per day against DuPont for leaks that plaintiff’s attorney contended lasted for three years.

U.S. District Judge Shelly Dick presided over the case.

Follow David J. Mitchell on Twitter, @NewsieDave.