The General Services Administration and the Department of Homeland Security issued what's called a record of decision Thursday night on Plum Island. The document marks one of the last steps before a sale.
But critics say most of the island should be turned into a nature preserve with limited development.
"While a sale is not yet imminent, this latest news serves as a reminder of the critical need for federal legislation to preserve this unique, priceless natural treasure," U.S. Sen. Richard Blumenthal, D-Conn., said in a statement. "Once this pristine open space is lost to development, it can never be reclaimed."
Blumenthal and U.S. Rep. Timothy Bishop, a Democrat from Long Island, have introduced a proposal to stop the sale altogether. Bishop's district director, Brian Beedenbender, said Friday that "it remains foolish to sell off an environmental treasure."
Congress voted in 2009 to close the laboratory, which opened on the island 100 miles east of New York City in 1954. Plum Island scientists research pathogens like foot-and-mouth disease, which is highly contagious to livestock and could cause catastrophic economic losses and imperil the nation's food supply. Sale proceeds would go toward moving the research to Kansas State University.
A GSA environmental study in June suggested homes might be built on Plum Island, but there has been no estimated sale price for the island.
The two federal agencies said in a statement they issued the record of decision after considering "all the factors discovered and analyzed" during the National Environmental Policy Act process.
When the timeframe for the laboratory's relocation is known, the agencies said, they will re-examine the environmental impact statement "specifically for the purpose of ensuring that it reflects the then current knowledge of the conditions on the property."
Environmentalists have sounded alarms that selling the island would jeopardize endangered terns, seals and other wildlife, and the federal Environmental Protection Agency raised some red flags earlier this month. The island provides "important habitat for a number of species," and the GSA hadn't done a detailed enough evaluation of selling the island, regional EPA administrator Judith Enck said.
In 2007, the New York state Department of Environmental Conservation said there appeared to be no existing environmental threats on the island, noting that hundreds of tons of contaminated soil had been removed from landfills and other areas there.
But Adrienne Esposito, executive director of Citizens Campaign for the Environment, said concerns over contamination would likely affect the island's potential sale.
"It's most like riddled with contamination, and a thorough investigation needs to occur," Esposito said. "You can't just sell an island that was used in secret for 50 years."
The local town board approved new zoning laws Tuesday that would prevent any significant development of the island. Under the zoning rules approved unanimously by the Southold Town Board, the bulk of the island would be preserved as a conservation district while laboratory research would be allowed on part of it.
Southold Town Supervisor Scott Russell said Friday that his first choice would be to keep Plum Island open and providing jobs to area residents, but the zoning regulations should at least restrict future development.
"You will see no Plum Island Estates on Plum Island," Russell said.
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