Is the Cholla plant on a Navajo reservation? The only one I could definitely find like that is this one, which is the one I meant. It made some news sources when it shut down because, like all major employers that shut down, it left a lot of people unemployed. In areas dependent on coal for jobs, this is a non-trivial concern.

In any case, between that and Cholla, ~2.6GW of coal-fired electricity shut down in Arizona since 2019. By comparison, the state generates 5.2GW from solar. (Though those aren't comparable, since coal-fired plants run more or less 24/7, but solar plants reach nameplate generation only for a few hours around noon, at most.)