Federal regulators said nuclear waste can be stored safely at Yucca Mountain, and Republicans quickly seized on the report to promote designating the Nevada site as the nation's permanent waste dump.

While the Nuclear Regulatory Commission said waste could be safely stored, it stopped short of endorsing the site in the final two volumes of its safety evaluation report. The Energy Department doesn't possess the land to build the site — that must be transferred by Congress — nor does it hold the water rights, a matter for the courts to decide.

But Republicans said the passing safety grade NRC gave Yucca eliminates opponents' arguments that nuclear waste cannot be safely stored.

“Today’s report settles it: To continue to oppose Yucca Mountain because of radiation concerns is to ignore science. This report says that Yucca Mountain would meet all of the Nuclear Regulatory Commission’s performance requirements for safe operation," said Sen. Lamar Alexander, R-Tenn., a Yucca proponent.

A 1982 federal law said Yucca must be studied for use as the nation's sole waste repository. House Republicans have cited the law when railing against President Obama's 2009 decision to pull the plug on federal reviews for using the site. A 2013 federal court ruling forced the NRC to revive its assessment of the site.

Although the GOP-led Senate would likely be more conducive to giving Yucca the thumbs up than the previous Democrat-controlled version, Senate Minority Leader Harry Reid, D-Nev., has vowed to never let it get built.

"The final volumes of NRC’s Safety Evaluation Report reiterate what we have known for years — Yucca Mountain is inherently flawed. It is flawed because the Department of Energy lacks the required land and water rights and has no reason to expect that it will obtain them in the future," Reid said.