The provision would allow spent nuclear fuel to be consolidated at temporary storage sites, as long as it stays in a state that has commercial nuclear power. Nevada and Utah would be explicitly ruled out as storage sites.

But governors in northeastern states, where many commercial nuclear reactors are located, don't like the change.

“We are deeply concerned and must strongly oppose language . . . that would suddenly shift long-established national policy on nuclear waste disposal by requiring commercial spent fuel at local or regional federal consolidated facilities in up to 31 states across the nation,” Rhode Island Gov. Donald Carcieri and Vermont Gov. James Douglas wrote on behalf of the Coalition of Northeastern Governors.

The governors also say the bill includes an aggressive timetable to set up the storage sites that doesn't give enough time to evaluate safety, security and environmental effects.

The interim storage plan in the legislation opposed by the governors serves as an alternative to Private Fuel Storage's push to park 44,000 tons of spent nuclear fuel on the Skull Valley Goshute Indian Reservation, 50 miles from Salt Lake City.

The Nuclear Regulatory Commission approved a license for the facility last year, but electric utilities backing PFS have abandoned the project and Congress passed a law complicating plans to ship waste by rail to the site.

In any interim storage scenario, the waste would presumably be eventually buried at a permanent repository at Yucca Mountain, Nev., or the Energy Department might develop technology to recycle the nuclear material.

The Northeastern governors argued in their letter last week that building a system of temporary storage sites could undermine the push for a permanent repository.

There are about 54,000 tons of used commercial nuclear fuel awaiting disposal in 31 states, according to the Nuclear Energy Institute.

The nuclear storage language was added to the bill by Energy Committee Chairman Pete Domenici, R-N.M.; Senate Minority Leader Harry Reid, D-Nev.; and Sen. Bob Bennett, R-Utah.

Bennett had hoped to have the bill through the Senate before senators left for their monthlong August recess, but it was pushed back and Bennett said last week he doesn't anticipate it will be a top priority when senators return in September.

Anti-nuclear and environmental groups also oppose moving the waste to centralized facilities, arguing that the temporary sites would become permanent ones lacking necessary security and safeguards and that state governors would be cut out of the process.