Los Alamos, the Atomic City, is facing a legacy of its nickname. High levels of plutonium present in samples taken in July from soil, plants and water in Los Alamos’ Acid Canyon may be the oldest contamination in the state, predating the 1945 Trinity Site atomic test, said Michael Ketterer, an analytical chemist and retired professor of chemistry from Northern Arizona University. “There are some references to contamination being introduced into Acid Canyon starting in 1943,” he said Thursday. “It is very logical to me that this is some of the earliest produced material.” The legacy plutonium c…