A panel of administrative judges ruled that the administration can't withdraw the application for a permit for Yucca Mountain, that it is up to Congress. (Decision document here)
This is likely to leave Yucca Mountain in limbo; the administration has requested no funding for the project. It does leave the option open to consider Yucca Mountain in the future, and it may make some difference in the deliberations of the panel charged with reviewing what to do with nuclear waste.
It may also provide fodder for some on Congress to criticize the administration for trying to shut down Yucca Mountain.