Meserve and three other commissioners were among witnesses testifying before the Senate Energy and Natural Resources Committee, which is considering a resolution to override Nevada's veto of the project.
The House passed its resolution early this month and the full Senate must do the same by July 25 for the project to enter its licensing phase.
While the commission feels deep underground storage is the best solution for dealing with nuclear waste, it currently remains neutral on whether Yucca Mountain should be a storage site, Meserve told the committee.
"Based on our technical reviews and pre-licensing interactions (with Department of Energy), we believe that sufficient information can be available at the time of a license application," Meserve said. "We believe the final environmental impact statement contains enough information ... to provide a foundation for a site recommendation."
Although the legislative process is focused on whether Yucca Mountain is a proper site, much of the hearing dealt with the issue of transporting nuclear waste across the country. Congress is "putting the cart before the horse" by picking a site before it takes care of a shipment plan, said Jim Hall, former chairman of the National Transportation Safety Board and now a paid adviser to Nevada.
"The DOE has spent $7 billion looking into Yucca Mountain's geology, but less than $200 million on transportation of nuclear waste," Hall testified. "While some might have accepted this approach before Sept. 11, no one should now."
Sen. Craig Thomas, R-Wyo., took offense at the idea Congress would ignore the transportation issue after any approval of the Yucca site but Hall said his government experience suggested regulatory agencies, which he did not name, might have trouble following through on congressional directives in that area.
Meserve said the NRC is confident spent nuclear fuel and other waste can be transported safely to Yucca from the country's several dozen nuclear power plants and DOE facilities. Sens. Ben Nighthorse Campbell, R-Colo., and John Ensign, R-Nev., challenged the NRC's procedures for testing shipment casks using scaled-down canisters and computer simulations.
Meserve said the NRC will ask for funding in the fiscal 2004 budget to conduct full-scale testing of future cask designs.
Ensign suggested an incident similar to last summer's Baltimore, Md., train tunnel fire could damage a cask enough to release radioactive contaminants. Meserve said initial NRC studies of conditions during the fire indicated a cask would have remained whole under such a scenario.
Ensign repeated another concern of Yucca opponents -- that terrorists could use anti-tank missiles to penetrate a cask.
NRC Commissioner Edward McGaffigan Jr. said regulations take into account reasonable threats and suggested terrorists would use such a difficult-to-obtain weapon on less risky targets with greater immediate impact, such as chemical storage tanks.
NRC Commissioner Nils Diaz said breaching a storage cask would be serious but unlikely to lead to catastrophic consequences.
The Energy and Natural Resources Committee is scheduled to vote on the override resolution June 5, said Sen. Jeff Bingaman, D-N.M., the committee chairman.