pleased to provide an update on the Caspiche gold-copper project in the
Maricunga region of Chile. Recent activities have focused on enhancing
and advancing the necessary engineering studies for the potential
development of the extensive, near-surface, copper-free, oxide blanket
at Caspiche as a relatively simple heap leach operation.
Activities completed include the following:
- An engineering study considering the feasibility of a
power line extension from the nearby Maricunga mine supply to provide
power requirements for a potential oxide heap leach operation.
- A geotechnical evaluation of the proposed Caspiche mine
site, focused primarily on the footprint of the oxide heap leach
operation.
- A hydrological and hydrogeological study on the Caspiche
area, focused on the heap leach operation but also, where applicable,
incorporating the overall mine (oxide plus sulphide) and process plant
footprint.
Engineering Study – Power Line Extension:
Previous studies on the Caspiche oxide deposit considered
that power would be supplied from generators installed at the project
site. Exeter contracted POCH, an engineering group based in Chile but
with offices and operations in Mexico, Colombia, the USA and Australia
amongst others, to complete an engineering study to consider the
feasibility of extending the existing Maricunga mine power line to
Caspiche, a distance of 12 kilometres. The line would be used to supply
power initially to the heap leach operation.
The cost of the extension of the power line and all
associated electrical infrastructure and substations is estimated to be
in the region of US$12 million (“M”), approximately US$10M less than
that assumed in earlier studies utilizing on-site generators. More
importantly, grid power would provide cheaper electricity to the
operation.
The study includes the following key conclusions:
- There is sufficient capacity in both the existing
substation connected to the National grid and the power line to the
Maricunga mine to carry the additional load estimated for the Caspiche
heap leach project.
- The power line extension would follow a reasonably
smooth corridor and as such there are no additional construction
constraints over and above those associated with the altitude at which
the power line would be constructed.
- The power line corridor takes consideration of potential
future installations associated with the larger concentrator project
and does not interfere with them.
Geotechnical Evaluation:
Knight Pièsold has completed a geotechnical evaluation of the
Caspiche project area, which included a field campaign of 43 trenches,
18 drill holes and collecting some 90 samples. The objective was to test
key sites to evaluate their suitability for process facilities and heap
leach pads, amongst others.
The study conclusions show that the project can be built using conventional construction methodology with key parameters of:
- Conventional cut and fill slope angles ranging from 1.5 – 2:1.
- Earth fill slopes of 1.5:1.
- Foundation thicknesses of 1m or greater depending on size of structure.
- Compaction to be 95% of modified Proctor maximum dry density or to a minimum relative density of 80%.
In addition, the study calculated a preliminary estimate that
more than 2,000,000 cubic metres of material suitable for concrete
aggregate is available, largely eliminating the need to locate aggregate
sources outside of the project construction area.
Caspiche Hydrology and Hydrogeological Study:
The study, conducted by Schlumberger Water Services (“SWS”),
was focussed around the heap leach project and open pit, although
consideration has been taken of the overall project footprint where
applicable. SWS used Exeter”s water level monitoring measurements from
24 drill holes, drilled two additional hydrogeological holes, carried
out a field testing program of slug, packer and pumping tests and fitted
2 drill holes with vibrating wire piezometers for long term monitoring
of water table changes.
Preliminary report conclusions include:
- A mean annual precipitation of 113 millimetres (“mm”)
was determined, of which 67 mm corresponds to precipitation as snow and
46 mm to precipitation as rain.
- At the latitude of the Caspiche project area, the bulk
of the precipitation falls during the Chilean winter. Summer
precipitation rates are low, reflecting the weak nature of the Bolivian
winter effect at the relatively southerly latitude of the Caspiche study
area.
- The hydrological modelling indicates that inflow to the
surface of the waste rock dump is between approximately 0.6 and 1.08
litres/second (annual average) for the mean annual precipitation.
- The rate of water infiltration from the waste rock dump
to the underlying groundwater system is very low. At the end of
operations the dump would be capped, or alternatively measures put in
place to remove snow cover from the dump surface with the possibility of
reducing infiltration to zero.
Water Exploration
Exploration drilling for a new water source dedicated
exclusively to the Caspiche project began in May before being curtailed
by weather. A news release specific to water exploration drilling can be
expected.
Exeter”s Unique Position
Exeter Chairman, Mr. Yale Simpson states: “Exeter is in a
unique position for a junior explorer. We have a world class gold-copper
asset in an excellent jurisdiction, $57 million cash and no debt. In my
view the current share price does not reflect the potential future
value of the Company, a value that, if realized, could well be a
multiple of our current valuation given a further improvement in metal
prices and economic conditions. Another Caspiche-size deposit has not
been found for years, simply because they are increasingly scarce in a
world starved for natural resources.”
Mr Jerry Perkins, Vice President Operations a qualified
person as defined in NI 43-101, is responsible for preparing the
information contained in this news release.
About Exeter
And this is what it means: