Radioactive contamination in groundwater may be 400 times higher than the federal standard at the Hanford Nuclear Reservation in Washington state because high-level nuclear waste was buried 40 years ago in containers that had no bottoms, the U.S. Energy Department said on Friday. The department’s groundwater manager said the contamination will likely reach the Columbia River. Meanwhile, newly released documents show that groundwater has also been contaminated in Paducah, Ky., where a uranium processing plant spread plutonium outside the plant’s boundaries. Last year, the DOE launched an investigation into the plant after the Washington Post reported on problems there, and the investigators concluded that groundwater contamination wasn’t a problem. However, the new documents, which only just came to light after the Washington Post uncovered them, map out plutonium in soil and water more than a mile from the plant. When confronted with this evidence on Saturday, the DOE promised to investigate (again).