Rocky Mountain Arsenal, where nerve gas, chemical weapons and then pesticides once were made, is marking the end of years of cleanup work to turn contaminated prairie land into a national wildlife refuge northeast of Denver.
On Friday, U.S. Interior Secretary Ken Salazar and Hew Wolfe, an acting deputy assistant secretary of the U.S. Army, signed a document transferring the last parcel from the Army to the U.S. Fish and Wildlife Service for the refuge, covering about 25 square miles.
"The deal is done," Salazar said, before turning to shake Wolfe's hand in an outdoor ceremony on a warm, fall day.
In November, once workers finish removing two water treatment plants that are no longer needed, the $2.1 billion cleanup will be done about a year ahead of schedule and under budget, said Charlie Scharmann, U.S. Army program manager for the arsenal.
"It's hard to believe we're here," said Carol Rushin, a deputy regional administrator for the Environmental Protection Agency.
The arsenal was once farms, but homesteaders agreed to give up their land in 1942 after the Japanese attacked Pearl Harbor so the U.S. Army could make chemical weapons there.
The site kept operating through the Korean and Vietnam wars, and rocket fuel made at the arsenal helped send astronauts to the moon, Wolfe said.
After World War II, the Army leased land to private companies, including Shell Oil Co., which made pesticides and agricultural chemicals there until 1982.
The next year, Colorado filed a lawsuit alleging the Army and Shell had damaged its natural resources.
The land became a Superfund site in 1987, and the EPA declared it among the most polluted sites in the country. Over the years, parts of the refuge came off the Superfund list as Shell, the Army and contractors worked on cleanup.
During the work, crews found grapefruit-sized bomblets containing sarin, a nerve gas, that had to be destroyed. In 2008, the arsenal temporarily closed to the public after the chemical agent lewisite was found.
Meanwhile, Colorado negotiated a settlement of its lawsuit that had Shell and the Army giving the state about $27.4 million, plus 100 acres north of the arsenal for conservation.
Salazar said the arsenal and another wildlife refuge west of Denver at the site of the former Rocky Flats chemical weapons plant show how urban areas can be connected to the great outdoors.
"We can use this as an example of what we can do in other metropolitan areas all around the country," said Salazar, wearing a cowboy hat, faded blue jeans and cowboy boots.
The refuge, with the Rocky Mountains clearly visible to the west, is home to black-tailed prairie dogs, hawks, coyotes, bald eagles and deer. In 2007, 16 bison were introduced to the prairie. The herd has now grown to 48, refuge manager Steve Berendzen said.
A $7.4 million visitors center, funded in part with stimulus money, should be complete next year.