Public health advocates also called for the government to post signage warning visitors so they can make an informed decision about using a trail contaminated with toxic waste.
Members of the general public can’t make this sort of informed decision. They don’t have the very specific background knowledge necessary. Plutonium in small amounts is not dangerous unless you eat it or breathe it in as dust. How much Plutonium dust is in the air near this trail? What is the level of radiation exposure from it compared to the background level that everyone is exposed to? What risk of cancer does the increased exposure correspond to?
These are questions that experts are able to answer but almost all hikers aren’t. The general public already trusts experts to regulate nuclear power plants, radiology equipment, etc. It makes no sense to want a warning sign here unless you already live in a state of constant paranoia.