Hillary Clinton's extensive ties to a Nevada nuclear waste project may raise new questions about her softening opposition to it.

Yucca Mountain, a proposed radioactive waste repository roughly 100 miles north of Las Vegas, was a frequent target of both Clinton and then-Sen. Barack Obama as they fought for the Democratic nomination in 2008. Clinton, who once pledged to close the site "forever," attacked Obama for accepting donations from a corporation that had lobbied for Yucca Mountain.

But Clinton walked back promises to shutter the site during a swing through Nevada this summer, Jon Ralston reported Tuesday in the Reno Gazette-Journal.

"[I]t is off the table based on what I know right now," Clinton said of the nuclear dump.

Pressed by Ralston on whether she was "equivocating," Clinton argued that "science is always changing" but noted the government must "figure out what we're going to do with nuclear waste."

The former secretary of state fundraised at the home of a Yucca Mountain contractor in September. In addition, she has welcomed a number of bundlers who have actively pushed to keep the nuclear dump open.

The September fundraiser, hosted by former Shaw Group CEO Jim Bernhard, cost guests $2,700 to attend, $27,000 to cosponsor and $50,000 to sponsor.

The Shaw Group lobbied extensively for Yucca Mountain in recent years, spending nearly $2 million lobbying for issues that included the Nevada repository in 2010 and 2011.

In 2008, Bernhard's company won a major contract to operate Yucca Mountain. The firm that purchased Shaw Group in 2012, Chicago Bridge & Iron, continued to lobby the government on Yucca Mountain.

Officially selected as the site of the nation's nuclear waste in 2002, Yucca Mountain has been under near-constant fire from environmentalists and Nevada politicians, including Senate Minority Leader Harry Reid.

The Government Accountability Office found President Obama's ambitious plan to move the proposed waste site from Yucca Mountain was motivated largely by politics, not by science, in an April 2011 report.

That report said "there is no guarantee that a more acceptable or less costly alternative will be identified" if Yucca Mountain is shuttered before lawmakers hammer out a new plan for the country's spent nuclear fuel.

Clinton's campaign chair, John Podesta, has longstanding ties through his brother to a lobbying firm that netted $540,000 from the Nuclear Energy Institute, a key Yucca Mountain backer, Ralston noted.

He also pointed to four campaign bundlers, each of whom has raised at least $25,000 for Clinton, who had ties to Yucca Mountain advocacy groups.

Sen. Bernie Sanders has expressed opposition to leaving the nuclear repository at Yucca Mountain.

The Vermont socialist's views have pulled Clinton left on a variety of issues as she struggles to dampen his popularity among progressives, including on the Keystone Pipeline and on the president's Pacific trade deal.

Clinton's apparent wavering on Yucca Mountain mirrors the nuanced approach she has taken to Wall Street reform.

The former secretary of state has been accused by her critics of staking out a friendlier position on big banks than Sanders given her deep ties to Wall Street.