The Spring issue of AZGS's online magazine, Arizona Geology includes a report by Steve Rauzi, Oil & Gas Administration for the Arizona Oil & Gas Conservation Commission, addressing the question of whether hydraulic fracturing ("fracking") is a concern in Arizona.
Fracking has become more widespread since its use in producing natural gas from shales. Bad drilling or completion practices in some areas may have allowed frac fluids to leak into aquifers, causing critics to blame the fracking process itself. [Right, shale gas plays in the US. There are none recognized in Arizona. Credit, US DOE Energy Information Administration]
Among Steve's conclusions, he notes that,
There are no shale-gas wells in Arizona and there has been no horizontal drilling and no hydraulic fracturing associated with those types of wells. In fact no wells have ever been drilled in Arizona for shale-gas. The geology of Arizona does not include the extensive areas of the type of shale formation that shale-gas developers are looking for.
Only ten wells have been hydraulically fractured in Arizona in the last 15 years. Seven were fractured in 1997, one in 2004 and two in 2008. All of the wells were drilled for carbon dioxide gas, not shale gas, in east-central Arizona between St Johns and Springerville.