The Strong and Harris copper-zinc-silver deposit is a sub-type of or related to a classic copper skarn (Einaudi and Burt, 1982; and Meinert et al, 2005). Skarn deposits range in size from a few million to 500 million tonnes and are globally significant, particularly in the southwestern US. They can be stand-alone copper skarns, which are generally small, or can be spatially and temporally closely associated with porphyry copper deposits, in which case they tend to be very large. The skarn at Strong and Harris and collectively in the Cochise mining district is presumably related to the Texas Canyon Quartz Monzonite, despite the intrusive itself hosting very little known economic mineralization. Mineralization in the quartz monzonite would require more specialized conditions involving the metal and volatile content of the magma, depth of emplacement, or other factors (Burt, 1977).

Copper skarns generally form in calcareous shales, dolomites and limestones peripheral or adjacent to the margins of diorite to granite intrusions that range from dikes and sills, to large stocks or phases of batholithic intrusions, and frequently are associated with mineralized intrusions. Copper mineralizing hydrothermal fluids are focused along structurally complex and fractured rocks and convert the calcareous shales and limestones to andradite-rich garnet assemblages near the intrusive body, and to pyroxene and wollastonite rich assemblages at areas more distal to the intrusive. Retro ........

The PEA presented in this report considers open-pit mining of the Strong and Harris project.

Road and Ramp Design
Road designs have been completed for the PEA to allow primary access for people, equipment, and consumables to the site. This includes haul roads between the designed pits, dumps, and proposed leach facility. Within the pit designs, ramps have been established for haul truck and equipment access. The in-pit ramps will only require a single berm. Ramps outside of the pit will require two safety berms. Onelane traffic ramps are also utilized near the bottom of pits where the strip ratio is minimal, and the traffic requirements are low.

The ramps and haul roads assume the use of CAT-777 haul trucks with an operating width of 20 feet. For two-way access the goal of the road design is to allow a running width of near 3.5 times the width of the trucks. MSHA regulations specify that safety berms be maintained at least ½ of the diameter of the tires of the haul trucks that will travel on roads. The ½ height of the CAT-777 haul trucks tires is 4.5 feet. An extra 10% was added to berm height design to ensure that all berms are sufficient in height.

Safety berms assume a slope of 1.5 horizontal to 1.0 vertical. Considering that ramps in the pit only need one berm, the road width of 85 feet was determined for two-lane traffic, which allows for 3.5 times the operating width of the haul trucks. Single-lane traffic roads are estimated to ........

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