Comparison of 2023 Phoenix AMA Groundwater Model and Resolution EIS Groundwater Model

To assess the cumulative impact associated with use of groundwater for the Resolution Copper Project, modeling of proposed Resolution Desert Wellfield (DWF) pumping in East Salt River Valley (ESRV) was conducted in 2020 in support of an Environmental Impact Statement (EIS) using what was then ADWR’s current Phoenix AMA groundwater model. Results indicate that without Resolution DWF pumping, but including all other reasonably foreseeable future uses, pumping depths to groundwater beneath the Desert Wellfield at the end of a 100-year predictive period would be approximately 550 feet. In June 2023, ADWR published an updated version of the Phoenix AMA model showing new depth to water projections for the 100-year predictive period would be approximately 800 to more than 1,000 feet beneath the Desert Wellfield.