Due to an editing error a portion of a letter by Tim O’Flaherty, “Find Yucca alternatives,” which appeared on Sept. 30, was deleted. It should have read: “If we were to get all of our power from nuclear plants we would generate not 2,000 tons but 25,000 tons a year. The Yucca Mountain repository was designed to hold 75,000 tons.” We regret the error.