DENVER — A U.S. official harshly criticized a Colorado health officer who questioned the safety of a former nuclear weapons plant and said he did not trust the federal government's assurances that the site was thoroughly cleaned up before being converted into a wildlife refuge.
The dispute is part of a decadeslong battle over the operation and cleanup of the Rocky Flats facility outside Denver, which made plutonium triggers for nuclear weapons for decades. Part of the site is now a wildlife refuge, and the government plans to open hiking trails and visitor facilities there this year.
Environmentalists and community activists have sued to try to block the plan.
Mark Johnson, health director of Jefferson County, which includes the site, said he's not sure the area is safe despite a $7 billion Superfund cleanup.
In a court document and an interview with The Denver Post , Johnson questioned the trustworthiness of federal officials who say the site has been cleaned up and expressed doubts about the expertise of state health department officials who helped supervise the work. He called for an independent review.
The newspaper interview prompted refuge manager David Lucas to chastise Johnson in an email sent Sunday from his government account and obtained by The Associated Press.
The email called Johnson's comments "reckless and irresponsible" and accused him of misconduct for questioning the credentials of state health officials. Lucas said Johnson should retract his comments and apologize.
In an interview, Lucas defended the email.
"It was a very professional letter," he said. "It explains our position on what occurred."
Dr. Larry Wolk, head of the Colorado Department of Public Health and Environment, said he stands by the expertise of state officials who worked on the cleanup and also called Johnson's comments reckless.
"I don't make that statement lightly," he said Friday.
Wolk has said both his department and the U.S. Environmental Protection Agency concluded that the Rocky Flats cleanup is complete. He said a proposed trail through the refuge does not pose a threat to public health.
Johnson told the AP on Friday that he stands by his statements about site safety but wishes he had expressed his concerns about Colorado officials differently. He confirmed the authenticity of Lucas' email.
The U.S. Department of Energy, which operated the plant and oversaw the cleanup, did not immediately respond to an email seeking comment.
The lawsuit seeking to block the government from opening the refuge to the public says the site is too dangerous because of the potential presence of plutonium and other hazardous materials.
It alleges that the U.S. Fish and Wildlife Service, which manages the refuge, did not complete a required analysis of environmental risks. It also claims the agency did not examine contamination on about a square mile of land recently added to the refuge.
The agency has said it would not open the refuge to the public if it was unsafe.
Randall Weiner, an attorney for the groups that sued the Fish and Wildlife Service, said Lucas' email is troublesome because he works for the agency and Johnson had submitted an affidavit supporting some of the groups' claims.
"Rather than responding in court, he's sending out a public statement that lambastes him, and I don't think a defendant should be doing that," he said.
The Rocky Flats plant operated from 1952 until 1989, when U.S. agents raided it to investigate safety and environmental violations. Production never resumed, and the government decided in 1993 to close it down and clean it up.
After the cleanup, 8 square miles (21 square kilometers) on the perimeter became a refuge. Perched on a high mesa northwest of Denver, it offers sweeping views of the foothills and plains and is home to bear, elk, deer and the endangered Preble's meadow jumping mouse.
Two square miles (5 square kilometers) in the interior of the site, where the plutonium was handled, is off-limits and remains under Energy Department control.