"One thing I will say about this is, the hilly scrub desert where the claims are would probably not be a major concern to environmentalists unless some ugly water issue raised its head."

Cochise County is in the Chihuahuan Desert.  It is higher and colder than the Sonoran Desert around Tucson and Phoenix.  Arizona also has two other distinctive types of desert, the Mojave and the Great Basis. 

As to water issues around Hay Mountain, I don't think that is too much of a concern, especially where open-pit mining may be feasible for near-surface deposits - the skarn.  It's the deep underground workings where vast amounts of water are needed.  Besides, in the history of mining at Tombstone, flooding of diggings was an issue because the water table was so high, and it still is.