DENVER — The U.S. Army and Shell Oil Co. agreed Monday to pay up to a record $1 billion to clean up a Colorado arsenal described as possibly the most contaminated site on Earth. The 12-year project could eventually turn a toxic stew into a public park.
But the state hinted that it might try to block the plan in an attempt to obtain more influence in deciding how the Rocky Mountain Arsenal will be purged of pollutants and what will become of it.
Specifics such as the method and exact timetable for the massive mop-up have not been worked out, and the full environmental toll remains unmeasured on both the 27-square-mile site and surrounding communities.
"We're extremely excited," said Jim Scherer, regional administrator of the Environmental Protection Agency, adding that "we're still probably looking at the year 2000 for final, ultimate cleanup."
Scherer said that, in terms of size and toxicity, the Rocky Mountain Arsenal "is the most,or certainly one of the most," contaminated sites in the world. It is among 951 sites that the EPA has placed on its Superfund priority list.
The Justice Department sued Shell in 1983 under the federal Superfund law seeking reimbursement for cleaning up the arsenal and for damage to natural resources.
The proposed consent decree reached by the Army and Shell is the largest and most expensive cleanup of a hazardous waste site ever, with rough estimates putting the bill at $750 million to $1 billion, the Justice Department said. The settlement requires federal court approval.
"It's historic," said Miles Flint, a Justice Department deputy assistant attorney general who joined representatives of Shell, the Army and the EPA in announcing the settlement at a news conference here.
For 38 years, the arsenal on grasslands just north of Stapleton International Airport was an isolated center for the production and storage of chemical weapons such as mustard and nerve gas and white phosphorous firebombs. The waste includes arsenic and mercury compounds also. Starting in the 1950s, the Army leased land to private companies that manufactured dozens of pesticides and herbicides.
The arsenal's military mission ended in 1980, and Shell, the last tenant, closed its pesticide plant two years later. The Army has spent $125 million and Shell has spent $25 million on cleanup projects over the years, but the dispute over the degree of responsibility has dragged on in the courts.
Terms of Agreement
Under Monday's agreement, the Army and Shell must share the cleanup cost 50-50 for the first $500 million, with Shell paying 35% of the next $200 million and 20% of all costs over $700 million.
The state of Colorado, which has separate suits over the arsenal pending against the federal government and Shell, was not a party to Monday's agreement.
"This is not a final remedy, only a settlement between two parties," Howard Kenison, deputy state attorney general, said. "It's safe to say the state wants a larger role . . . ."
Kenison said in a telephone interview that the state is "happy steps are being taken to resolve problems at the arsenal" but wants a guarantee that state cleanup standards will be met and the welfare of its residents taken into account.
Cancer Risk Cited
He said a risk assessment undertaken by the state determined that the contamination could increase cancer deaths by one out of 100 people if it found pathways--such as blowing soil--to human beings.
Poisonous chemicals already have streamed out of the arsenal and into nearby drinking wells, forcing a multimillion-dollar cleanup separate from Monday's agreement.
The new agreement recognizes "the remote possibility that in the future the Army may have to take immediate action at the arsenal to respond to an imminent threat to human health."
Gov. Roy Romer, who attended a Super Bowl homecoming parade for the defeated Denver Broncos Monday, was not available to comment on the agreement. Romer has said that he would like to see the arsenal eventually converted to a "Central Park" for Denver.
The agreement between Shell and the Army says that the arsenal should be cleaned sufficiently to permit commercial and industrial development, public recreation, public park land and wildlife refuges. It does not allow residential development.
Shell spokesman Gary Dillard said the oil company's contamination involved about one-third of the property but that payment was based on the volume and degree of toxicity there.
Relied on Mother Nature
"It's important to note that the disposal practices being employed were believed to be the best at the time," Dillard said. "People anticipated that Mother Nature would be much more forgiving, and I think that's where the mistake was made."