New “Danger Radioactive” Signs Posted Near Rocky Flats Trail Entrances

New warning signs near trail entrances to the Rocky Flats National Wildlife Refuge are bringing renewed attention to the site's nuclear history and the continuing debate over public access.

9NEWS reports that the bright yellow signs prominently display the radiation symbol and warn visitors that entering the Rocky Flats National Wildlife Refuge “may expose you to radioactive materials.” The signs also provide historical context about the former Rocky Flats Plant, where plutonium components for nuclear weapons were manufactured for decades.

Boulder County installed a warning sign near the Coalton Trail connection at Highway 128 after requests for additional public information about Rocky Flats. The county's sign explains that radioactive and hazardous materials were released during plant operations, that cleanup removed contaminated structures, soil and water, and that some radioactive and hazardous materials remain in soil and groundwater. Visitors are encouraged to make an informed decision before entering the refuge.

For community advocates who have pushed for stronger signage around Rocky Flats, the signs represent an important change. People involved in the effort told 9NEWS that they see the warnings as a step toward greater transparency about the history of the site and the concerns that continue to surround it.

The signs do not end the longstanding disagreement over present-day risk at Rocky Flats. They do, however, make something unmistakable to visitors arriving at the trails: this landscape has a nuclear history, and that history remains relevant to decisions being made about Rocky Flats today.

Source: 9NEWS, January 28, 2026 — “‘Danger Radioactive’ warning signs posted near Rocky Flats trail entrances.”