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To date, McEwen Mining and NGE have advanced the project adding the following exploration datasets at Grass Valley:

Hydrogeochemistry

McEwen Mining and NGE completed a hydrogeochemistry sampling program in the larger Grass Valley, and delineated a large, previously unexplored target area on the west side of Grass Valley based on a NNE lineament of upwelling groundwater containing anomalous concentrations of gold and other trace elements associated with Carlin-type mineralization.  When evaluated in the context of the regional geology, the hydrogeochemistry results suggested a possible underlying mineralized fault system projecting northward towards Barrick’s Cortez Property that may have cross cut underlying gold mineralization.

Surface Geochemistry

Several rock, soil, and vegetation geochemistry sampling programs have been completed on the Project by McEwen Mining.  The results show localized concentrations of elevated gold and trace element chemistry along areas defined by anomalous hydrogeochemistry in patterns that further suggest the presence of NNE trending structural zones beneath the project area.

Project Scale Geologic Mapping

McEwen Mining geologists have mapped the exposed range front geology in the context of the regionally important structural controls.  The mapping identified upper plate rocks with widely-scattered, small areas of hydrothermal alteration coincident with anomalous gold and trace-elements in the rock geochemistry samples.

Seismic

McEwen Mining has acquired historical seismic geophysical data, originally collected in the late 1980’s for a research project designed to characterize the deep crustal structure of north-central Nevada.  McEwen Mining has re-processed this data to provide information at shallower depths more appropriate for gold exploration.  The reprocessed data identified a complex fault system dipping to the west and exhibiting characteristics associated with older reactivated structures regarded as favorable for Carlin-type gold deposits elsewhere in Nevada.

Gravity

McEwen mining has completed a detailed gravity geophysics survey at the Project and successfully outlined a broad area of bedrock covered by an estimated less than 100m (300ft) of sand and gravel extending 3.2km (2mi) from the exposed range front for the entire length of the 8km (5 mi) long target area.  These results provided further evidence that depth of cover at the project is potentially shallow and within economic constraints, and that the target area is large enough to contain a significant mineralized system.