State: Just a few hundred yards from Lake Robinson lies an old waste pond that, until this year, was among the least of Duke Energys worries in the Carolinas. The pond had virtually dried up and, as coal ash basins go, didnt appear to present the same threat to groundwater, rivers or lakes that other ash basins do, environmentalists say. But documents that have surfaced recently show the unlined 55-acre basin has leaked arsenic and it has the unusual legacy of being a dump site for low-level nuclear...