NWM provides Gold production and Lluvia de Oro mine update
TORONTO, April 28 /CNW/ --
TSX Venture Exchange
Symbol: NWM
Shares Outstanding: 402,069,593
TORONTO, April 28 /CNW/ -
Au Production
Gold production has begun from the newly-stacked heaps at Lluvia de
Oro. Leaching of Pads SW1 & SW2 is resulting in the gold extraction
which was predicted, and is expected to yield a little over 1000 oz. Au
by June 30. Four new heaps are being stacked in coming months, so that
total gold production by year-end 2011 should exceed 12,000 ounces Au.
Gold Pours
The ADR Plant and Refinery at Lluvia de Oro are recovering gold as
expected. The planned expansion of heap leach capacity during the
remainder of 2011 will result in a requirement for expanded gold
recovery circuits. Expansions to each unit in the gold recovery
circuit have been designed and budgeted, and are in the early stages of
equipment procurement and construction.
Mine Preparation
During late 2010 and early 2011, major pre-stripping of ore reserves was
accomplished at Lluvia de Oro. This work has allowed the concurrent
development of multiple ore mining zones. As a result, ore stacking on
new heaps is planned at over 250,000 tonnes per month from now until
end of 2012.
Ore mined at Lluvia de Oro is being segregated into 4 grade ranges for
optimal processing.
These grade ranges are:
High Grade HG 1.00 g/tonne Au, and higher
Mid Grade MG 0.35 - 0.99 g/tonne Au
Low Grade LG 0.20 - 0.35
Sub Grade SG 0.10 - 0.19
Heap Leach Pad Preparation
Four cells on Pads SW1 & SW2 are now under leach and delivering pregnant
solution to the ADR Plant. Two more cells will be loaded with ore from
the Creston Pit during May and June. Pads SW1 & SW2 will have a total
of 800,000 tonnes of Mid Grade MG ore under leach by August.
Pads 7, 8 & 9 are being prepared for new ore delivery which is expected
to commence in July. Leaching on Pads 7, 8 & 9 will commence in
August. These Pads will have 400,000 tonnes of Mid Grade MG ore under
leach by November.
Construction is underway on the new Lluvia Dos Pad, which will have
capacity for all Lluvia ore reserves currently known (design capacity
is 45 million tonnes). Two special lanes on this pad will be stacked
to just 3 meters depth with High Grade (HG) ore (grades averaging 1.5
g/tonne Au). Crushing and Conveyor Stacking of HG ore will begin in
late July, and leaching will begin in August.
One lane of the Lluvia Dos Pad will begin receiving Mid Grade (MG) ore
in September. The MG ore will be stacked to a height of 10 meters. A
new lane for MG ore will be constructed every 4 months to match mine
production output.
A large Pad for Low Grade (LG) ore will be completed by October. The
tonnage of LG ore is significant at Lluvia, and a lower cost pad is
planned for processing it, by Dump Leaching. The Dump Leach Pad will
hold 4 million tonnes of LG ore and will be stacked to a height of 35
meters.
Ounces Forecast
All Lluvia ore in the HG and MG classifications are part of the NI
43-101 compliant reserves reported in July 2010. The NI 43-101
reserves include all ore stacked on Pad SW1 & SW2, Pads 7, 8 & 9, Pad
HG and Pad MG. These Pads are forecast to be stacked with 2 million
tonnes of HG and MG ore during 2011.
If this Pad loading rate is achieved, the HG and MG ore stacked will
contain 43,000 ounces Au, all part of the published NI 43-101
reserves. Based on the leaching recovery rate projected in the NI
43-101 technical report of July 2010, over 10,000 ounces Au are
forecast to be leached and recovered by year-end 2011.
Production Plans for 2011 - 2012 forecast more than 5 million tonnes of
ore will be stacked and leaching by end of 2012, all from the published
NI 43-101 reserves for Lluvia de Oro. These ore tonnes will contain a
total of approximately 100,000 ounces of gold. Gold recovered and
produced is thus forecast to be over 50,000 ounces by end of 2012.
Copper Control
Copper control at Lluvia de Oro and La Jojoba will be achieved by three
methods (A, B & C), each independent and operating in sequence.
A. The first method is segregation of leach solutions by gold and copper
content, so that each metal can be removed and recovered by distinct
processes. Blending of gold-rich and copper-rich solutions will be
avoided by the leach pad design and leaching sequence.
B. The second method is aggressive removal of copper within the gold
plant, by addition of a series of extra process operations targeting
the copper. These extra operations occur in carbon adsorption, acid
washing of carbon, cold stripping, electro-winning, sludge processing
and refining.
C. The third method is a novel process called ASPN. This stands for
Acidification, Sulfidation, Precipitation, Neutralization. It differs
significantly from its cousin, the SART process. It has two important
features. The first feature is the relative simplicity of the process,
which leads to lower capital costs. The second feature is the planned
close proximity to the heaps producing the copper-rich solutions, which
leads to lower operating costs.
Currently at Lluvia de Oro methods A and B are in use and operating.
These two methods are sufficient for Lluvia ores because they are
relatively low in copper content. Method C (ASPN) will be applied to
Jojoba ores, which have a copper content 4 times greater than those of
Lluvia ores.
Method C (ASPN) is currently being tested on site at Lluvia. Copper
precipitation from the gold-rich solutions has been demonstrated. The
ASPN process will soon be operating as a continuous-flow pilot-scale
test, processing bleed streams from different heaps with varying ore
characteristics. During the pilot-scale testing phase, method A allows
copper-rich solutions to be segregated for testwork and optimization of
the ASPN process.
The full-scale application of the ASPN process is expected to be
constructed and operating at least a year before Jojoba ores are being
mined and leached.
On March 10, 2011 NWM provided a press release stating that it had
terminated the lease to own arrangement for the BioteQ SART plant.
BioteQ has launched a suit for damages and NWM disagrees with the
BioteQ allegations and intends to defend against them vigorously.
This press release has been prepared by R. Bruce Thorndycraft, Chief
Operating Officer for NWM Mining Corporation.
CAUTIONARY STATEMENT ON FORWARD-LOOKING INFORMATION
This news release includes 'forward-looking information', as such term
is defined in applicable securities laws. Forward-looking information
includes, without limitation, the success of exploration activities,
price outlooks, production expectations and other similar statements
concerning anticipated future events, conditions or results that are
not historical facts. These statements reflect management's current
estimates, beliefs, intentions and expectations; they are not
guarantees of future performance. The Company cautions that all forward
looking information is inherently uncertain and that actual performance
may be affected by a number of material factors, many of which are
beyond the Company's control. Accordingly, actual future events,
conditions and results may differ materially from the estimates,
beliefs, intentions and expectations expressed or implied in the
forward-looking information. Specific risks that may also occur are
gold recovery circuits may be added at a slower rate than expected,
parts may not be available or suitable, weather could impact on the
rate of pad loading and leach solution application, ores may have
higher levels of copper than expected, ore grades on the pads may be
lower than expected. All statements are made as of the date of this
news release and the Company is under no obligation to update or alter
any forward-looking information.
Neither the TSX Venture Exchange nor its Regulation Services Provider
(as that term is defined in the policies of the TSX Venture Exchange)
accepts responsibility for the adequacy of this release.
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please contact NWM Mining Corporation at (416) 364-6799