LAWRENCE, Kan. (AP) — A 42-year-old University of Kansas building that formerly housed a small, experimental nuclear reactor has been reduced to rubble. The Lawrence Journal-World reports that Burt Hall was demolished to help clear space on campus for expansion of the School of Engineering complex. The nuclear reactor was removed from Burt Hall in the early 1990s. But the demolition took several months as workers carefully searched for any radioactive material. Associate engineering dean JoAnn Browning said she knew of no traces of radiation being found. Browning says officials looked ways to re-use the building, but concluded the demolition was cheaper than making necessary repairs. The $80 million engineering complex makeover will include two new buildings, six large classrooms, labs, research facilities and a renovated library.