The Air Force has some instruments and dust that they want to dispose of as waste, but the instruments have dials which glow in the dark, thanks to radium paint (also in the dust).
So here's an article about the disposition of the waste. The article says the AF classified the waste as naturally occurring.
Well in a very broad sense all waste is naturally occurring (it's not supernatural!).
But what "naturally occurring" refers to in this case is the nuclide. If the nuclide was formed by natural processes it is naturally occurring. In the case of radium it is formed by the decay of uranium and thorium which were incorporated into the Earth as it evolved into a planet. So this nuclide, and therefore the waste is properly classified as naturally occurring (or Naturally Occurring Radioactive Material, NORM sometimes called TENORM when the NORM has been technically enhanced or concentrated by humans).
Contrast with cesium-137 which is formed by the fission of uranium in a man-made reactor. The cesium-137 is not naturally occurring (though if some natural uranium in the ground were to concentrate and fission without any human interaction, the cesium-137 formed would be naturally occurring).
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