YAKIMA, Wash. (AP) - Energy Department officials in Washington D.C. are assuming a larger role overseeing construction of a massive plant to treat radioactive waste in south-central Washington. The $12 billion vitrification plant at the Hanford nuclear reservation is among the largest industrial construction projects nationally, both in cost and sheer size. Shirley Olinger, manager of the Energy Department's Office of River Protection at Hanford, had managed plant construction and retrieval of underground tank waste since 2007. An internal Energy Department memo obtained by The Associated Press says Olinger will no longer oversee the construction project but will retain her other responsibilities. An onsite project director instead now reports to managers in Washington D.C.