In this Oct. 13, 2005 file photo, deer cross a road stripped of its asphalt at the former Rocky Flats Nuclear Weapons plant near Golden, Colo. 

(AP Photo/Ed Andrieski, file)

Five environmental groups are seeking a court injunction to halt construction of hiking and biking trails at the Rocky Flats Wildlife Refuge.

The groups say dirt samples taken from the former nuclear weapons site northwest of Denver  between 1991-2005 displayed levels of plutonium that is not safe, despite cleanup efforts.

“[The U.S.] Fish and Wildlife Service made the assumption that the land it was going to receive was pristine land, clean land, as clean as the soil in yours and my backyard. And that was a dangerous fiction,” said Attorney Randall Weiner, representing the groups.

Plaintiffs in the civil action are Rocky Mountain Peace and Justice Center, *the nearby development* Candelas Glows, Rocky Flats Grows, Rocky Flats Right to Know, Rocky Flats Neighborhood Association, and Environmental Information Network.

The U.S. Fish and Wildlife Service, USFWS acting director Greg Sheehan, and Secretary of the Interior Ryan Zinke are among those named in the injunction.

A federal judge tossed out a previous version of the lawsuit last year, saying it was premature. Last week, Denver Public Schools joined a number of other school districts *when it* announced its students would be barred from visiting the refuge because of worries about the potential health risk.

“We live in the state of Colorado, where there are plenty of opportunities to enjoy the outdoors,” DPS school board member Lisa Flores told the Denver Post. “This is a site we can take off that list.”