Extensive clean up work done on Plum Island

According to government documents obtained by The Associated Press, extensive efforts have been made since 2000 to remove contaminants and waste from the top-secret Plum Island germ warfare research station in New York.

The Department of Homeland Security is preparing to sell the 840 acre island located off of northeastern Long Island, but environmentalists still worry that it has not be adequately cleaned up.

"We are highly concerned that when the government acts alone they may not be doing the best job," Adrienne Esposito, executive director of the Citizens Campaign for the Environment, told The Associated Press. "Every government cleanup needs the public's involvement and independent oversight to ensure its validity."

Plum Island was used in the 1950's to study pathogens with offensive and defensive purposes. The island was chosen because federal laws at the time banned germ warfare research on the U.S. mainland.

According to David Huxsoll, a former Plum Island administrator who spoke to The Associated press, the site was used to study anthrax for decades in a biocontainment lab. Spores of anthrax may remain dormant and survive for long periods in the environment.

Plum Island is expected to sell for between $50 and $80 million. The research lab on the island will be moved to a site at Kansas State University in Manhattan, Kan.