Montgomery & Associates

This table summarizes hydraulic conductivity estimates from testing of wells and boreholes during hydrologic characterization activities conducted by Montgomery & Associates (M&A) during the period 2004 through 2012. To date, results of hydraulic testing and analysis have been provided in individual reports or technical memoranda for wells or groups of wells completed over the course of the 8 year period from 2004 to 2012.

Phase II hydrogeologic investigations were conducted at the Far West Site to characterize principal hydrogeologic units and structural features, hydraulic properties of units in the unsaturated and saturated zones, and the occurrence, movement, and chemical quality of groundwater. Hydrogeologic investigations were conducted in conjunction with geotechnical investigations by Klohn Crippen Berger (KCB) in support of the Resolution Copper Mining LLC (RCM) tailings prefeasibility assessment for the Far West Site.

Figure showing groundwater systems, Apache Leap Tuff Aquifer, Magma Mine Workings, and Resolution deposit.

This draft technical memorandum has been prepared to summarize hydrogeologic data and provide an assessment of hydrogeologic conditions and water uses in the vicinity of the Whitford, Silver King, and Happy Camp sites (Near West area) for the RCM Tailings Prefeasibility Study (PFS).

Map of water contours in the upper Queen Creek / Devil's Canyon study area.

This tech memo has been prepared to summarize results of the Phase I hydrogeologic assessment of the Near West site, conducted by Montgomery & Associates in support of RCM's ongoing prefeasibility studies for storage of RCM mine tailings. The purpose of the Phase I assessment was to conduct non-invasive field investigations to supplement information obtained previously from published data and to plan Phase III investigations involving subsurface exploration drilling and hydrologic testing.

This tech memo has been prepared to summarize results of the Phase II field investigations of the Near West site, conducted in support of RCM's ongoing prefeasibility studies for storage of RCM mine tailings. The purpose of Phase II investigations was to conduct electrical resistivity surveys to assess the potential occurrence of shallow groundwater at the Near West site.

An investigation of hydrogeologic conditions for the Superior Basin has been completed by Montgomery. The chief objective of the survey was to evaluate the cause of recent water level declines reported for some wells located within and adjacent to the Queen Creek corridor through the Superior Basin, as well as observed declines in discharge from Whitlow Ranch Dam.

The goals of the baseline surface water monitoring program are to: a) Refine understanding of surface water  occurrence, quantity, and quality within the study are b) Develop a baseline data set against which future potential impacts from mining may be measured, and c) Support development of an EIS.

In February 2010, Montgomery published a report entitled "Interim Results of Groundwater Monitoring, Upper Queen Creek and Devils Canyon Watersheds" (M&A 2010) which reported all hydrochemical and isotopic data available through the second quarter of 2009. The current report presents hydrochemical and isotopic data collected since M&A 2010 was published.


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Public Hearing Comments

Draft EIS

The draft EIS public comment period closed November 7, 2019. All 30,000+ comment submittals are now under review for consideration in the compilation of the final EIS.

Media & General Info

Point of Contact
John Scaggs
Tonto National Forest

Apache Leap Special Management Area
Apache Leap SMA website