A northern Ontario First Nation believes there’s new proof people have been victims of mercury poisoning — and still are.

Chief Simon Fobister of Grassy Narrows held a press conference in Winnipeg Tuesday with Judy Da Silva, a mercury survivor from the Ojibway community 225 kilometres southeast of Winnipeg, to announce they’ll redouble pressure on Ontario to clean up a newly reported site of a mercury dump and the Wabigoon River system it likely contaminated.

A former Dryden paper mill worker had earlier told media he helped bury dozens of barrels of contaminant in a shallow pit decades ago, with little more than a shovel and tarps to protect it from leaching into the ground. The location of the reported site is not publicly known.

Ontario meanwhile takes the claim of the previously unknown pit very seriously and it’s looking at remediation.

“We take all public claims very seriously. Upon receiving new information last fall, local (ministry) staff connected directly with both Chief Fobister and Mr. Glowacki to address their concerns. Ministry staff also presented information on the Mercury Waste Disposal Site at the next Working Group meeting in January 2016 after being requested to do so by Chief Fobister,” said an spokesman from the Ontario Ministry of Environment and Climate Change by email Tuesday.

Next week, two senior Ontario politicians will visit the northwestern Ontario First Nation.

Ontario Environment and Climate Change Minister Glen Murray, who is a former mayor of Winnipeg, and Ontario Indigenous Relations and Reconciliation Minister David Zimmer are due to spend part of the day June 27 in Grassy Narrows.

“We’re gearing up to meet with the minister(s) and we want to get the message out that we want this river cleaned up,” Fobister said.

Guilt is said to have driven Kas Glowacki forward to reveal the existence of the toxic dump he says he helped dig behind the Dryden pulp and paper plant when he worked there in 1972. Glowacki’s account made headlines in the Toronto Star, which is investigating Grassy Narrows’ environmental contamination.

“This is a new site that no one was aware of until this man admitted there is another site. We don’t know if it’s leaking mercury … We want the (Ontario) government to investigate it, locate it and clean it up,” the chief said. “No more fancy talk, no more studies. We just want it cleaned up.”

For decades, that province has said mercury contamination from the paper mill in the 1970s has long since ceased being an environmental hazard.

Under Liberal Premier Kathleen Wynne, Grassy appeared to be making headway in having the existence of mercury recognized as a continuing environmental and health threat. But now Grassy Narrows leaders say the existence of a second dump is straining that new trust.

“We’re willing to work with the Ontario government but if they don’t want to work with us, we’ll find a way to access the site and demand the clean-up,” Fobister said.

The ministry email, which confirmed the minister is travelling to Grassy Narrows at the end of June to meet with local leaders, indicates Ontario officials are sensitive to the strained relationship and the need for action to clean up any of the toxin that may have leaked.

“Moving forward, we want to work with Grassy Narrows First Nation to gather the data in the Wabigoon River system between Dryden and Clay Lake, focusing on present day conditions in water, sediment and biota. This information will be critical in determining what an effective remediation strategy would look like,” the email said.

“The Ontario-Grassy Narrows Working Group, which includes local community members, provincial ministries and representatives of the federal government, continues to lead these discussions,” the email said.

Grassy Narrows has a population with soaring rates of neurotoxin-related disease and has maintained the source of the problem is the river where they fish for food.

“It’s not like there’s a Safeway in the reserve. Our people live in poverty, on $200 a month. The food from the land sustains us,” Da Silva said.

So politically sensitive is the sheer mention of the word “mercury” that local doctors refuse to link symptoms to Minamata disease, a neurological syndrome caused by severe mercury poisoning, the Grassy Narrows grandmother said.

“It’s an endless battle and the ones who end up in hospital? We say it’s mercury poisoning. It’s labeled Alzheimer, dementia or Parkinson’s. We all know it’s mercury. I feel someday I’ll be in that hospital bed, labeled with a neurological disease that’s not recognized as mercury poisoning,” Da Silva said.

“We have many people who suffer from mercury poisoning… we’re always being minimized, always being told natural remediation will happen,” Da Silva said.

A scientific study Grassy Narrows commissioned in 2010 showed mercury continued to contaminate the environment.

In May, a group of independent scientific mercury experts said one meal of Grassy Narrows fish has 150 times the safe level of exposure to mercury. They also said it’s possible to clean up the mercury contamination.

Those experts, now working with Grassy Narrows, have characterized the area as one of the most heavily contaminated in Canada and they say in 30 years, levels have not only failed to decline, they’re actually continuing to spread downstream to new locations.

Multiple generations of Grassy Narrows people suffer debilitating physical problems with vision, balance and trembling, which they feel are the impacts of mercury poisoning. Nothing has been done in 45 years since the paper mill dumped 9,000 kilograms of mercury into the waterways that supply fish and water to Grassy Narrows and their neighbours.

“The mercury doesn’t stop at Grassy Narrows — it goes to other non-indigenous communities — just to let you know this is not a racist mercury,” Da Silva said.