*Edit: Except when they do.
*Edit: Except when they do.
Hence, chemical pollution very often goes unnoticed for decades until somebody starts to wonder why half the babies in town are born without brains.
There was even a case where alarms were sounded when a power plant worker was found to be radioactive due to radon in his home, which triggered detectors at work. The general chemical industry doesn't operate with anything even remotely close to this degree of care.
Anything like that radioactive source from Australia would set of tons of alarms in a nuclear power plant. You wouldn't get it out the door. Incidents like that missing radioactive source in Australia happen where there are far fewer safeguards than at a nuclear power plant. Those sources generally go missing from abandoned medical equipment, food irradiation facilities, and that sort of thing. You'd be hard pressed to smuggle (let alone accidentally convey) something like a spent nuclear fuel pellet out of a power plant.
In addition to the requirement of a more active approach needed to detect ground/water contaminants there are also a larger variety of pollutants that are harmful. Many of these need specific tests, which can consume your samples. Of course we can do pretty good guesstimates for what we should look for, but we do need to recognize that the process is both more fuzzy and more involved. We can grow these projects by making them cheaper, but that's a tall order (it is happening though).
Edit: I do want to note that most radiation detection devices do not distinguish between types of radiation. These differences do matter in danger levels. This can add complications the above but there is a decent signal that is still useful. But as with everything, some expertise and domain knowledge is quite important.
Not quite true. There are pretty big and active citizen based radiation detection projects [0,1,2,3]. The reason for this is that radiation monitors are quite cheap now and the same people who build weather systems often connect a geiger counter. They're cheap and sensitive since the gov spent so much money trying to detect radiation from space, across borders, and even the smallest traces on people (to detect spies, scientists, etc) all from the Cold War. There are also citizen based communities monitoring water and soil, but this does require more work from the participant. They have to go out and collect samples. Processing can be both expensive and quite a bit of work. This isn't the same as hooking up a $100 device to your weather station, which is a leave and forget type system.
We should note that both these communities are far more active in regions where there are greater dangers (history of nuclear sites/projects, oil facilities, military bases, etc). I'd also like to thank both these communities and others like them. They're all doing important work.
[0]https://www.radiationnetwork.com/
[1] https://jciv.iidj.net/map/
[2] https://cemp.dri.edu/cemp/
[3] https://www.epa.gov/radnet/near-real-time-and-laboratory-dat...