WASHINGTON -- Lawmakers who were briefed Wednesday on the Energy Department's revised schedules for the Yucca Mountain Project pressed the nuclear waste repository director for a new accounting of how much the project will cost.

DOE in 2001 set a $57.6 billion price tag to build tunnels within the mountain ridge and to ship spent fuel from commercial nuclear reactors for emplacement at the site, 100 miles northwest of Las Vegas.

But that was based on a projected 2010 repository opening, a goal that was set aside.

On Wednesday, project director Ward Sproat outlined a revised March 2017 target to members of the House energy and air quality subcommittee.

The panel's chairman, Rep. Ralph Hall, R-Texas, said it was difficult to weigh the project without an update on funding, a point echoed by others.

Absent a "clear understanding" of revised costs, "it would be impossible for Congress to assess whether or not new legislation is needed," said Rep. John Dingell, D-Mich.

Sproat said DOE would submit new costs in the fall. Talking to reporters earlier, Sproat said he did not believe the numbers have changed but he planned to examine them.

In March, DOE Deputy Secretary Clay Sell said costs might decrease after completion of a project redesign that eliminated several multibillion-dollar fuel-handling facilities.

Wednesday's hearing was Sproat's debut before Congress as the Yucca Mountain director. A former nuclear industry executive and consultant, the Pennsylvanian was confirmed by the Senate in May to head the Office of Civilian Radioactive Waste Management.

Citing his industry credentials, Sproat said, "I am committed to getting the Yucca Mountain project unstuck."

Sproat said a June 30, 2008, deadline to complete repository designs and apply for a construction permit is a near-certainty. He said the date falls on a Monday, "and I do not plan on working that weekend."

But other milestones will depend heavily on whether Congress cooperates by passing a DOE bill to make available full funding from the repository's construction account, expand the repository capacity, withdraw the site from public land status, and allow the department to obtain water rights.

Rep. Joe Barton, R-Texas, said the bill might pass the House but has little support in the Senate.

The schedule also is dependent on minimal delays from lawsuits filed by the state of Nevada and other Yucca critics. Nevada officials said this week they plan to continue pressing the state's opposition in the courts.

In Nevada on Wednesday, former Gov. Bob List, a paid consultant for the pro-Yucca Nuclear Energy Institute, maintained the new schedule means DOE is serious about Yucca Mountain and the state should reconsider its stance.

"I see it as a real wake-up call to Nevada officials, that they better go to Plan B and deal in a forthright way with the project and recognize the realities," List said.

Clark County officials said they were skeptical that DOE can meet the new deadlines.

"The trouble with DOE's schedules is that they are not often reliable and are always subject to change because they leave no room for the myriad of variables," said county Planning Director Irene Navis. "While it's true that DOE can't predict or control all of them, many of them are known, and are just not well accounted for."

In Washington, Energy Committee lawmakers said they wished Sproat well. But several said that others have made promises in the project's long history, and they will believe progress when they see it.

"We applaud the schedule," said Rep. John Shimkus, R-Ill., but he called a reluctance by lawmakers to believe the schedule "justifiable."

"This is not just embarrassing. This is costing the country a great deal of money," said Rep. Charles Norwood, R-Ga. "If it takes 30 years to open up that mountain, I've got great concerns."

Barton pointed out the repository will be 19 years late from its original 1998 startup date.

"There are those that hope that late means never," Barton said. "I am frustrated by the lack of progress at Yucca, but I'm not giving up."