Some refer to them as “Cold War Heroes,” and they’re now the subject of a search by the University of Iowa. Researchers in the U-of-I College of Public Health are trying to track down the thousands of people who worked with nuclear weapons at the Iowa Army Ammunition Plant in southeast Iowa.Howard Nicholson , a research assistant at the college, says the University’s trying to find all four thousand workers from the so-called “Line One” plant near Burlington. Nicholson says the search may very well extend into every state in the U-S and other countries.Nuclear weapons were made at the plant between 1946 and ’75. It was among only two plants in the U-S where atomic bombs were both assembled and disassembled. Nicholson says the former Line One workers will be asked about what materials they came in contact with during their employment at the plant and how their health is now.Former plant workers are urged to call (319) 335-4210.