Boulder County commissioners are considering whether to continue supporting a project that would create a new trail connection on land contaminated by plutonium that’s next to the former Rocky Flats nuclear weapons plant.

On Thursday, the Boulder County commissioners heard from a panel of people who urged them to withdraw support from the regional trail project. The commissioners heard public comments from residents who oppose it. They did not take any action or make any decisions about the project.

Boulder County resident Giselle Herzfeld said she recognizes the project has already begun and that the funds have already been committed and recommitted to the project.

“Please do the right thing,” Herzfeld said. “Please step outside of any perceived limitations due to a bureaucratic obligation and look into the depths of your own human morality to recognize it is never, ever too late to do the right thing.”

The project, called the Rocky Mountain Greenway, is a regional trail project that aims to connect the three Front Range National Wildlife Refuges — Rocky Mountain Arsenal National Wildlife Refuge, Two Ponds National Wildlife Refuge and Rocky Flats National Wildlife Refuge — with Rocky Mountain National Park, through an interconnected, multi-use trail system.

Part of the project includes creating a trail connection point between Boulder and Broomfield counties at Rocky Flats by creating a pedestrian bridge across Indiana Street and an underpass at Colo. 128. However, some residents and activists are concerned that any trail construction would disturb potentially contaminated land and cause public health issues.

Rocky Flats employees worked with plutonium, highly-enriched uranium, beryllium and other materials from 1952 to 1989. Plutonium is used to make nuclear weapons. The former plant was designated as a federal Superfund site, and a 10-year, $7 billion clean-up was completed in 2005. The 1,300 acres the plant sat on are not open to the public, but the 5,237 acres around it are designated as a public wildlife refuge called the Rocky Flats National Wildlife Refuge.Jon Lipsky, the retired FBI agent who led the raid that resulted in the nuclear plant being permanently shut down for environmental crimes, was one of the panelists who spoke on Thursday. He explained how contaminants continue to affect the site.

Panelist Michael Ketterer, an emeritus professor at Northern Arizona University who also teaches in Denver, completed sampling and testing at Rocky Flats in 2024, which detected plutonium in the wildlife refuge’s air samples. Not only did he prove that plutonium is in the air at Rocky Flats and triggered by wind, the concentration of plutonium he found violates Colorado’s laws.

Deborah Segaloff, who is involved in Physicians for Social Responsibility Colorado, a nonprofit group, explained the dangers of plutonium and why the Rocky Mountain Greenway project poses a risk to public health. Segaloff said the main way the body takes up plutonium is through inhalation, which, according to the U.S. Department of Health and Human Services, is the most dangerous way to be exposed.

The development of the Rocky Mountain Greenway would cause people to track plutonium and other carcinogens outside of Rocky Flats and into their homes, parks and other public spaces, Segaloff said.

“Installation of the underpass would greatly disturb soil of the refuge, including soil many feet below the surface which may be more heavily contaminated than surface soil,” Segaloff said.

“The greenway would encourage greater use of the trails on the refuge, disturbing the surface soil and potentially generating contaminated airborne dust.”

Diane D’Arrigo, the radioactive waste project director for Nuclear Information and Resource Service, said there are no safe levels of radiation exposure for any living thing, despite guidelines established by government agencies. Any level of radiation exposure can cause cancer, birth defects, heart diseases, reduced immunity, genetic damage and other health problems.

“Legal levels are not safe levels,” D’Arrigo said.

Randy Stafford from Rocky Flats Public Health Advocates concluded the panel by saying “it’s morally irresponsible” for the commissioners to promote recreational activities on a site like Rocky Flats.

“The safest thing to do is just to avoid the place,” Stafford said.

In 2016, representatives from Arvada, Boulder, Boulder County, Broomfield and Broomfield County, Jefferson County and Westminster submitted a Federal Lands Access Program Grant to extend the regional trail project and support the trail connections at Indiana Street and Colo. 128 at Rocky Flats. Some of the municipalities involved have since retracted their support for the project due to the radioactive nature of the site.

Longmont resident Chris Allred said withdrawing from the project is the right thing to do for the public health of the community.

“Join in solidarity with our neighbors in Broomfield, Westminster, Lyons and Superior who have all taken a strong position to oppose recreation at Rocky Flats,” Allred said.

Segaloff said it takes 24,100 years for a plutonium particle to lose half of its radioactive energy. So Rocky Flats will essentially be contaminated forever, she said.

Laura Matheney spoke to the commissioners about how members of her family helped build the nuclear plant and worked there. She described how her uncles and grandfather died from exposure working at the plant and that her aunts and mother have had secondary exposures from washing the clothes of the workers.

“The land deserves to rest,” Matheney said. “Those of us that live around the plant do not deserve to be exposed any longer to the chemicals that are out there … it needs to be left alone for our safety.”