Six people were killed in Picher, Okla., this weekend as a giant tornado swept through. The not-so-bright bright side: It’s likely that some fatalities were avoided, since many residents of Picher have already left. Picher is so polluted with mining waste that it’s listed as a Superfund site; the town’s booming lead and zinc mines closed decades ago, and its population has dwindled from 20,000 to 800. Now, as if the twister fatalities weren’t tragic enough — at least 17 other people were killed elsewhere in Oklahoma and Missouri — U.S. EPA officials are testing in Picher to see whether the town’s survivors are at risk from the lead-tainted dust blown off of the town’s huge piles of mining waste. After the tornado, “I think people probably have had enough,” says John Sparkman of the Picher housing authority. “There’s just nothing to build back to any more.”