Deep well injection, the process of storing or disposing of liquids waste deep underground, may seem like a safe way to get rid of toxic waste, but it is fraught with risks. It has been known to cause problems such as underground leakage, as was the case in January 2021 in Hutchinson, Kansas in the US.
Following a series of eruptions and explosions over a period of a few days which killed two people and forced hundreds to evacuate their homes, geologists found the source of the problems to be a nearby underground gas storage field. Natural gas had been injected into the field for a number of years. The gas leaked and spread for miles underground through rocks, eventually finding its way to the surface and releasing itself into the air.
Check out the original article here: https://www.propublica.org/article/an-unseen-leak-then-boom