A soil sample taken along the eastern edge of Rocky Flats National Wildlife Refuge near Indiana Street has turned up an “elevated” level of plutonium in the path of a planned four-lane tollway that would nearly complete the beltway around Denver.

The Jefferson Parkway Public Highway Authority, which is in charge of constructing the $250 million highway northwest of Denver, on Friday notified the Colorado Department of Public Health and Environment about the sample, which authority Executive Director Bill Ray confirmed was above 50 picocuries per gram.

Fifty picocuries per gram is the cleanup standard set for plutonium levels in the soil at Rocky Flats, where for 40 years components for nuclear weapons were manufactured. Health officials say that level of plutonium is the equivalent of increasing someone’s cancer risk by two in a million.

“It appears to be above the actionable level established in the closure standards, and we have asked for CDPHE’s guidance,” Ray said late Friday.

Dave Abelson, executive director of the Rocky Flats Stewardship Council, said the elevated reading is the highest he’s ever heard being found on or near the 6,200-acre refuge northwest of Denver.

“There were not readings historically this high in the buffer zone,” Abelson said. “It is something that demands much a more in-depth look, a much more in-depth conversation as to what it means.”

Historically, he said, soil samples on and around Rocky Flats have shown levels well below the 50 picocuries per gram action level for plutonium.

Neither officials with the authority nor with CDPHE would provide the precise level of plutonium discovered to The Denver Post on Friday.

Jennifer Opila, division director of Hazardous Materials and Waste Management Division at CDPHE, said in a statement that the agency doesn’t believe there is “an immediate public health threat” but that it will “continue to examine and analyze the data in the coming days once we have further information.”

Dave Lucas, refuge manager for Rocky Flats, said the elevated sample was taken from the “windblown” area at the eastern edge of the refuge, but not on the refuge, “where there is residual contamination and where we should expect to find any elevated results.”

“I will be waiting to see the entire data set,” he said before going into more detail.

The Jefferson Parkway authority said the reading came from a soil sample taken from land just west of Indiana Street, a little over a mile north of 96th Avenue. Two readings were taken from that single sample, and one registered as elevated for plutonium, while the other didn’t.

The authority said it hasn’t detected elevated plutonium levels in test results it has received from other samples it has taken in the right-of-way for the planned parkway. In all, it sampled 250 spots in the corridor along Indiana Street but won’t receive results from many of those samples until the fall.

Officials for Jefferson Parkway hope to break ground on the 10-mile highway connecting Broomfield to Golden next year. It has faced lawsuits and community opposition by those concerned that construction could potentially unearth plutonium and those who don’t want it near their neighborhoods.

It’s not clear what will happen to the construction timeline, given Friday’s news.

Plutonium has long been a bone of contention with those who have pushed to keep the national wildlife refuge from opening to the public because of health concerns stemming from the area’s history as a production center for the nation’s nuclear arsenal.

Rocky Flats, which closed in the early 1990s, had a long history of leakage and fires in which contaminants were carried by wind and water to areas outside the central production area, which remains a Superfund site and is closed to the public.

The former plant underwent a 10-year, $7 billion cleanup that concluded in 2005.

Jon Lipsky, the former FBI agent who led the raid on the plant in June 1989 as part of an effort to uncover environmental crimes at Rocky Flats, said Friday that the refuge should be “closed immediately.”

“Rocky Flats refuge visitors should beware,” he said.