A federal judge has ruled the Environmental Protection Agency overstepped its authority when it revoked a permit for one of the nation’s largest mountaintop removal coal mines. Fourteen months ago, the EPA said Arch Coal’s proposed Spruce No. 1 Mine in West Virginia would “use destructive and unsustainable practices that jeopardize the health of Appalachian communities and the clean water on which they depend.” The judge declared that the permit was now valid, paving the way for a mining project covering nearly 2,300 acres to go forward.