WASHINGTON -- The Department of Energy is refocusing its plans for a Nevada railroad to Yucca Mountain after the Walker River Paiute Indians announced they no longer were interested in having nuclear waste shipped across their reservation, a DOE official said Wednesday.

A Northern Nevada railroad corridor that would have crossed tribal territory in Mineral County will no longer be considered, according to Ward Sproat, director of the Office of Civilian Radioactive Waste Management.

DOE now will dedicate itself to completing studies of a rail corridor to the waste repository site that originates in eastern Nevada near Caliente, Sproat said.

"I wish they would have told us sooner, but they told us now," Sproat said of the Walker River Paiutes. Following a vote by its governing council, the tribe announced April 17 that it was withdrawing from environmental studies of the Mina rail corridor, named after a site on Highway 95 northwest of Tonopah.

Sproat said the Mina corridor studies essentially were done, and still would be included in an environmental impact statement that DOE expects to make public in October, along with its assessment of the Caliente corridor.

But, Sproat said, the Mina route "essentially wouldn't be considered as a viable alternative. So Caliente most probably we will end up sticking with and providing in our formal record of decision."

The DOE official gave a presentation to a conference organized by the U.S. Transport Council, whose members are organizations tied to nuclear materials shipping.

The tribe's participation was the key element of a strategy to route nuclear waste cargo on rail through Northern Nevada, and then south to the repository through old mining districts once served by rail.

Nuclear waste bound for Yucca Mountain would have used tracks that run through the middle of the Paiute community of Schurz.

As a possible condition of the tribe's participation, the possibility of relocating the rail line away from the town was being studied.

"I don't view this as a setback," Sproat said. "It is one less option that could have been cheaper and faster to build, but it is not something that is a major difficulty to us."

Gary Lanthrum, transportation director for the Yucca program, said the tribe's decision effectively closes the door on any rail route through western Nevada.

In the early days of the Yucca program, DOE identified a branch that would essentially go around the Walker River reservation.

But Lanthrum said in an interview that path was "longer and more problematic. It is very rough terrain, rougher than Caliente, and it makes (the route) as long or longer than Caliente."

Lanthrum also said he doubted there was time to develop other railroad options.

"The tribe said no before, then they said yes, then said no again," Lanthrum said. "We have done our due diligence looking at all the viable alternatives. I might feel better if the tribe were still at the table but they may still pay close attention to how the report comes out."

DOE officials and some in the nuclear shipping industry officials believed the 280-mile Mina corridor could have proved a less expensive and easier-to-build alternative to 319-mile Caliente corridor, where price projections have eclipsed $2 billion.

Critics say the Mina corridor could expose more communities to waste shipments. Opposition began to build in cities like Reno and Sparks.

Bob Halstead, a transportation consultant to the state of Nevada, said the Energy Department will have its hands full trying to develop the Caliente route.

"The assurances that we are hearing that this is not big deal that Mina has dropped off, maybe that is good damage control, maybe that is wishful thinking," Halstead said.

Halstead said DOE faces engineering challenges at several locations along the Caliente corridor, and also resistance from disgruntled ranchers and the sponsors of "City," a monumental desert art exhibit in Garden Valley.

"We think they are going to have problems with Caliente, and we are prepared for that," he said.