The agency has informed the Department of Energy that it wants to study adding newly cleaned-up Hanford Nuclear Reservation land to the monument.
The Tri-City Herald reported Tuesday that the proposal troubles the Tri-City Development Council, which worries that Fish and Wildlife control of the land could mean it would remain largely off-limits to the public.
The Energy Department plans to complete most environmental cleanup in the 220 square miles along the Columbia River by the end of 2015.
To prepare for that, TRIDEC hired a consultant to study recreational access and shared the proposed plan at public meetings in November. The goal is to present a proposal to Congress as the community's vision for future use of Hanford land.
The proposal includes public access for hiking, biking and camping, starting with a 7-mile section of trail along the river.
That would tie in with a proposal to turn the site into a Manhattan Project national park, allowing visitors to see what little remains of communities where settlers were expelled to make room for the secret project to produce atomic bombs during World War II.
"If we do not speak up, someone else will," said Gary Petersen, TRIDEC vice president of Hanford programs.
Rachel Jacobson, principal deputy assistant secretary for Fish and Wildlife and Parks, sent a letter Feb. 26 to David Huizenga, acting assistant secretary for environmental management, asking to discuss the final disposition of cleaned lands.
"The Department of the Interior and U.S. Fish and Wildlife Service treasure this landscape and we are deeply invested in the existing monument lands and the conservation values that will be realized as central Hanford area lands are remediated and preserved for the benefit of future generations," the letter said.
President Bill Clinton created the monument in 2000 and signed a memo mentioning the possibility of adding more land as cleanup advanced.
But TRIDEC is dismayed that so much of the land Fish and Wildlife already manages at the monument, about 70 percent, remains closed to the public.
"It seems to me Fish and Wildlife is pretty firm on limiting access to the national monument," said Carl Adrian, TRIDEC president. "I'm afraid this is more of the same."
The land remains closed to preserve almost pristine habitat, for tribal cultural issues and because of continuing cleanup on nearby Hanford land.
With Fish and Wildlife plans for the existing monument unfunded or incomplete, it doesn't make sense for the agency to take on additional land, Adrian said.
Petersen said that until Congress determines whether a national park is created, no action should be taken by any agency.