WASHINGTON -- Environmental groups and citizen activists Tuesday added to calls for the Department of Energy to broaden chances for the public to comment on potential changes to the Yucca Mountain program.

The groups urged the department to set aside a 90-day period for the public to weigh in on plans for a new railroad corridor to the nuclear waste site and for a redesign of waste-handling areas to accommodate multiple-use shipping and disposal containers.

"They are talking about a massive overhaul to the program, and this is completely under the radar of the public," said Michele Boyd, legislative director of Public Citizen.

The department in a Federal Register notice set aside a 45-day comment period on the two plans that expires Nov. 27.

Meetings in which the public could examine maps and register comments were scheduled over the first two weeks of November in Amargosa Valley, Las Vegas, Caliente, Goldfield, Hawthorne and Fallon.

Representatives of 17 groups signed a letter to Ward Sproat, director of the Office of Civilian Radioactive Waste Management, that urged the Energy Department to make more information available.

The signers included leaders of two Nevada groups, Citizen Alert and the Nevada Conservation League.

"The descriptions of the proposed actions in the Federal Register lack sufficient detail to enable the public to adequately assess and provide scoping comments," they said.

A third group, the Nevada Nuclear Waste Task Force, also has requested more time.

Also, the state government has urged the department to add public meetings in Reno, Elko, Battle Mountain, Winnemucca, Lovelock and Yerington, and in Sacramento, Calif., and Salt Lake City.

The Energy Department is "seriously considering" the request and is preparing to respond within 48 hours, spokesman Allen Benson said.