In accordance with EPA’s Coal Combustion Residual (“CCR”) rule, APS has installed monitoring wells around its coal ash impoundments. APS is on track to complete the required monitoring by October 2017 and at that time will determine next steps. Compliance with the CCR requirements will help APS characterize the integrity of its impoundments and their effect on groundwater, if any. APS has completed a full assessment of its coal ash impoundments and has determined that there are no underground conveyances that would allow the inadvertent discharge of coal ash.