The Waterkeeper group filed its federal pellet lawsuit in 2017, but for Wilson it continues several decades of work against local plastics and petrochemical factories around her home in Seadrift, Texas.
Sitting on the deck of her small, cabinlike house outside the small town, the 70-year-old grandmother of eight said she was something of a late bloomer to her causes.
A fourth-generation local resident who made her living in the commercial shrimping industry, she didn't get involved in environmental issues until she was about 40.
What drew her in, Wilson said, were news reports and Environmental Protection Agency data that said Seadrift and the rest of Calhoun County had, at that time, more chemical emissions than any other U.S. county.
It led her to a series of actions and legal battles against Formosa and other local factories, including hunger strikes and her decision to try to sink her own shrimp boat in protest — a plan interrupted by the Coast Guard — in waters outside Formosa's factory.
She wrote a 2005 book about her experiences, "An Unreasonable Woman: A True Story of Shrimpers, Politicos, Polluters and the Fight for Seadrift, Texas," garnering speaking engagements and an appearance on C-SPAN's Book TV program.
A short 2005 documentary, "Texas Gold," looked at her activism, and in 2002 Wilson helped start the women-led, national anti-war group CodePink.
Pellet pollution did not become a concern until more recently. Wilson started learning about it in 2009, after a Formosa worker contacted her.
"I became really focused on the pellets in 2009," she said. "I was talking to former workers and I was talking to workers inside the plant. ... There are ones that realize there's a problem, but they got a job and they don't want to lose it, so they will tell you things."
Today, several former Formosa employees are among the half-dozen people in the Waterkeeper brigade that regularly document pellet pollution. Some of them testified at the federal trial in March.
Still, it took years before the group started its waterside pellet monitoring.
At first, Wilson said members took their concerns to federal and state environmental regulators. She believes their efforts got the agencies to take some action, but she said that over time, the group felt that agencies either were not, or could not, be effective.
"I'm a regular citizen. I really believed, I really did, if you talk to the agencies, they are the ones who know and they will do something," she said. "I really believed it. That actually was one of the worst bubbles that broke for me is, 'No, they are not doing their job.'"
So in January 2016, the volunteers began their own pellet documentation effort, which eventually led to the lawsuit. The case is being funded by the Mercedes, Texas-based nonprofit Texas RioGrande Legal Aid Inc.
Wilson hopes the federal court action will put more pressure on Formosa. And she hopes that the final order could serve as a template for other companies.
She said the group wants stiffer fines and cleanup orders than the Texas CEQ decision in January.
"If it becomes serious enough, one, it will make them think twice before doing it again, and two, it will make other industries pay attention that now it's not like a free ride," she said.