https://www.atsdr.cdc.gov/toxguides/toxguide-8.pdf
I didn’t know that before but it appears cyanide does have a half-life that is a fraction of nuclear waste.
That doesn’t make it or the other compounds less dangerous, of course.
That’s uhh, not what that says. One of the two mentions of half life are your body converting cyanide into thiocyanate, which will kill you and depending on your last bowel movement, make your corpse into hazardous waste itself.
The other mention is hydrogen cyanide in air, which is lighter than air and will decompose back into cyanide eventually, scattering it over a large area. Which will technically make it go away from your site, but spreading toxic waste over the countryside is illegal for a reason.
Most cyanide in surface water will form hydrogen cyanide and evaporate.
As long as it has a surface to evaporate, it will degenerate.
Oh yeah, you could totally just leave it in a giant pool and ignore it. It’ll react, evaporate and eventually break down into cyanide again, rain down, subtly poison the area, react again, evaporate again, etc.
And that’s great for the owner of the big pool of cyanide, and very bad for everyone else. Stuff that evaporates doesn’t disappear, the cyanide doesn’t magically change into cookiedough. You’re just spreading it around more.
… Hydrogen cyanide is literally what has been used to execute people in gas chambers and genocide during the Holocaust. The LC(Lo), the lowest recorded lethal concentration is 107ppm, resulting in death in 10 minutes. That’s, objectively, far more dangerous than the respective material that firefighters were exposed to at Chernobyl. You don’t want that in any appreciable quantity in the air around people that you want to continue living.
