The Department of Energy has approved a new plan to deal with a stockpile of uranium-233 at Oak Ridge National Laboratory for an estimated $511 million.Using hot cells at ORNL's Building 2026 instead of erecting a new facility, the plan is expected to process the material by 2018 instead of 2029 and halves the cost of the previous plan, estimated at $1.1 billion, the Knoxville News Sentinel reported. Oak Ridge recently received formal approval to begin the processing phase of the project.The Atomic Energy Commission produced the U-233 in the 1960s during experiments looking into its potential in commercial reactors. Its disposition is a high priority for the lab because the material can also be used to make nuclear weapons. In 2003, the lab contracted with a consortium called Isotek to extract medical isotopes from the material and downblend it with depleted uranium for disposal off site. Over the years, the isotope extraction effort was abandoned and costs escalated from the original $128 million price tag.