Tank farm crews installed a mast for the Mobile Arm Retrieval System Vacuum inside tank C-105 at Hanford this week, the Department of Energy's Office of River Protection announced on its Facebook page.
The single-shell underground radioactive waste tank is the first to be cleaned using the vacuum version of the MARS technology. Officials said it uses as little liquid as possible during retrieval.
Tank C-105 is not on the list of 68 tanks suspected to have leaked. However, because of contaminated soil around the tank, Washington River Protection Solutions is taking a conservative approach and limiting the liquid used in waste removal.
DOE notified the state in June that tank C-105 was one of two tanks in the C Tank Farm that may not be emptied in time for a September 2014 consent decree deadline that requires all 16 tanks in the group to be emptied.
The World War II-era tanks contain radioactive sludge left from past production of plutonium.