CASS LAKE, MINN. — The pungent smell of creosote slowly faded after the St. Regis Paper Co. shuttered in Cass Lake in 1985, but toxic wood-treatment chemicals continued seeping into the groundwater, contaminating nearby lakes and decimating the neighborhood.

Only three homes remain. One is slated for demolition Monday.

"It wasn't always this way. This was a thriving community," said Brandy Toft, the Leech Lake Band of Ojibwe's Environmental Director.

St. Regis landed on the National Priority List, the nation's most polluted places, under the federal Superfund program. Forty years later, the 163-acre site in Cass Lake is still on that list. Tribal leaders say the Environmental Protection Agency has failed to remedy the contamination that has since spread and prevented the community from building housing for future generations.

South of the railroad tracks and Hwy. 2 is a vacant field where 40 homes once stood next to St. Regis. The houses, including a day care, were deemed unsafe and knocked down one by one as studies found the contamination was worsening. In 2003, the toxic soil led the EPA to call for immediate fencing in areas to prevent exposure to cancer-causing chemicals. The agency advised residents to eat no more than a dozen whitefish — an Ojibwe staple — from Pikes Bay and Cass Lake per year because of dioxin levels high enough to increase risks of cancer.

On Thursday, about 50 residents and officials gathered on the field to observe the 40th anniversary of the St. Regis Superfund designation. A moment of silence honored those who died from cancer before officials explained what it will take to complete the cleanup and why it has taken so long.

"This here has been going on, you know, maybe even before 40 years," said Tribal Chair Faron Jackson Sr. "I had relatives living in this area here back in the '50s. And a lot of my relatives have passed from cancer, too."

The St. Regis plant opened in 1957. Workers preserved raw lumber used as railroad ties and phone poles. International Paper Co. acquired ownership in the '80s. Toft said the company is not a cooperative or responsible party. "Everything goes to litigation," she said.

International Paper Co. did not respond to requests for comment.

Some Superfund sites in the state are cleaned within a few years. Others take decades. In Duluth's Morgan Park neighborhood, the U.S. Steel Duluth Works site along the St. Louis River closed in 1981. It took more than 30 years and $186 million to remove toxic waste. This summer, leaders announced the water is safe for swimming.

"It's both frustrating and heartbreaking to realize that while these sites are being dealt with, ours is lingering without the same level of attention and urgency," said Taylor O'Shea, a senior at Deer River High School and member of the Leech Lake and Minnesota youth councils.

O'Shea said action is needed "to ensure that the St. Regis Superfund site is not just a forgotten chapter in our community's history, but a success story of resilience and recovery."

EPA officials said St. Regis is the only Superfund site wholly within a reservation in EPA's Region 5, which includes Illinois, Indiana, Michigan, Minnesota, Ohio, Wisconsin and 35 tribes.

"We know that the length of time the complex cleanups like this would take are frustrating," said EPA Region 5 administrator Debra Shore. "But we at EPA want to work carefully and closely with the community to ensure that we get the job done right once and for all."

Superfund sites are investigated to determine the nature and extent of pollution. That has happened many times over the years at St. Regis, leading to the removal of some contaminated soil.

Some EPA studies and reports suggested the cleanup was done or nearing completion, but the Band's own studies contradicted the EPA data. In the early 2000s, researchers with the University of Minnesota found evidence of a worsening situation that the EPA seemed to miss.

"It's easy for a lot of people to say, 'Well, they didn't know any better when they were poisoning the water ... when they were poisoning the land, they didn't know any better.' But they really did," said Leo Anderson, who lived on a section of the Superfund site, as did his grandparents.

"One of the earliest memories I have of living on this site was that if you left a glass of water out overnight, in the morning there was an oil on top of it," Anderson said.

Twenty years ago, he began documenting the ravages of St. Regis in a film project, "Killing Cass Lake."

"We had repeated stories of these companies putting freshly treated creosote wood right next to people's homes," he said. "They would pile it as close as they could to your home until you moved out and then they would continue working their way through the whole community. So this was not a mistake."

"I think about the people that I love that died, the fact that my entire family is decimated, and it's not a unique story," Anderson said. "It's hard not to get angry."

Leech Lake Band elder Mike Smith Sr. said many went to their graves not knowing why they died. "And it was because of the contamination of this land here, and it's still contaminated to a degree. But that's what we're going to work on to correct that."

Shore said a team will begin sampling residential yards next year. Beginning this winter, she said, monitoring wells are being installed, and the EPA is reviewing health and ecological risk assessments. She said climate justice grants are available to fund the work "in communities that have been underserved for far too long."

Cliff Villa, deputy assistant administrator for the EPA, said part of Thursday's event was acknowledging mistakes while holding parties accountable and finding better ways forward.

"I just know from experience, it doesn't take 40 years to clean up Superfund sites," Villa said. "So I'm fairly hopeful that we're going to be seeing some more rapid progress here soon."

Toft said she wants to see children playing in the neighborhood again. She wants to see a revitalized area that is healthy and safe, and one that families don't have to fear once cleanup is complete.

The EPA would not say when that day may come.