A federal judge poured cold water on the U.S. government’s plans to build a nuclear waste dump at Yucca Mountain in Nevada this week — or, more accurately, he left the feds high and dry. The Department of Energy has been seeking 8 million gallons of state-controlled water to drill test holes at Yucca Mountain; the state of Nevada, which wants to be rid of the dump, has said no way. In a sharp slap to the DOE, U.S. District Judge Roger Hunt ruled that the federal government had “failed to demonstrate the necessity of its voracious water demands,” and he accused department officials of acting arrogantly. “The validity of Western states’ groundwater rights and the right to regulate water in the public interest is not a right to be taken lightly,” Hunt wrote in his opinion, “nor is it a right that can cavalierly be ignored or violated by a federal agency.” Our feds? Cavalierly ignoring or violating rights? Say it ain’t so.