I'm pretty sure for me "mining.fyi" wouldn't have created any associations with landmines (although "mines.fyi" does seem to match the contents of the website closer).
It'd be really interesting to see A/B testing results about what most people associate the word "mines" with (I wouldn't be surprised if that would be landmines in this day and age).
Even "mine.fyi" would be better at not making me think "landmine", although that would instead get read as "belonging to me".fyi.
I assume this is probably because most people don't see mines (as in gold mines) mentioned in plural very often. Or if someone does refer to multiple mines at once, they usually also specify the type of mine at the same time, like, "the cadmium mines in [country]" or similar. Or if talking about old, abandoned mines in an area, they're usually referred to as such.
The word "mines" on its own without an adjective usually does mean landmines, I think.
(I also immediately assumed this was about landmines.)
The US government has been pretty good about cleaning up the UXO it knows about, which means what's left is the UXO it doesn't know about. You'll find it near most of the current and former testing ranges, particularly Yuma Proving Ground where there's trails leading right from the adjacent BLM land into areas with potential UXO. The only real barriers are a few signs and the law.
Then I clicked on one and saw it was the name of our local rock quarry. :)