Johnston a toll may still be radioactive. Not sure.
They were using it for emergency landings less than twenty years ago.
Johnston Atoll is a wee bit radioactive still. I helped set up a coral sand screening system to separate the radioactive plutonium particles from ‘perfectly’ clean sand. The machine did a very good job of finding and diverting the contaminates.
At the time (late 1991 - early 1992) the country’s old chemical weapon stockpiles were being incinerated on the leeward side of the atoll. Before arriving personnel even cleared Immigration, we were given a briefing on the alarm system and an emergency response kit with respirators and atropine.
The ‘hazards’ from the Pu particles didn’t even warrant a mention in passing.