> groundwater pollution for example It is well below the water table > risk of explosion According to the article it is "self limiting" so that risk is very

> groundwater pollution for example It is well below the water table > risk of explosion According to the article it is "self limiting" so that risk is very small, and an explosion a mile underground is a lot less threatening than an explosion in a facility on the surface. A mile of rock is going to provide a lot more protection than any amount of concrete and steel. > potentially causing further natural events such as earthquakes From what I can tell (see for example https://www.usgs.gov/faqs/can-nuclear-explosions-cause-earthquakes https://www.usgs.gov/faqs/can-nuclear-explosions-cause-earth...), underground nuclear weapons tests, which have larger explosions than this could possibly create have a rather limited risk for earthquakes. I'm not a seismologist, but I think the risk there is less than the risk of an explosion in a reactor on the surface. > digging isn't cheap No. But it might be cheaper than building a large facility above-ground that meets all the necessary safety regulations for a nuclear reactor. And probably produces less carbon emissions in the process as well.