COVER STORY
Fall 2018 / Issue 59
What are the key components
and features of the modern mine?
Constant
water and
air control
Rehabilitation
of the site at
mine closure
to forest and
pasture
Tailings
embank-
ment design
resistant to
earthquakes
Maximum
recycling of
process water
A commitment to
use an appropriate
geo-textile mem-
brane (liner) for the
tailings dam
Dust control on all
roads to ensure
there is no dust
pollution
Zero discharge
from the mine
infrastructure in
to local water
Independent
ways
monitoring to
ensure
we deliver
on these
Improvement of
the water supply
to households
in Ilovica and
Shtuka
Social
investment
programmes
Ilovica-Shtuka’s primary product is Copper and the main
process of metal recovery is flotation, a physical process
that will produce a copper concentrate that will be trans-
ported to a smelter in Bulgaria.
These are the five main features that our modern mine
will comprise:
The mining area or Open Pit: This is much like a
quarry for limestone or aggregate and is where the rock is
extracted. The Open Pit is located on the opposite side of
the hill to Ilovica and Shtuka villages and will not be visible.
Extraction is carried out by fragmenting the rock in place
using highly controlled explosions once a day. The explo-
sions will be barely audible in the nearest residency. Once
fragmented the rock is loaded in to mining trucks using an
excavator. The extracted rock is either ‘Ore’, which is min-
eralised with copper and some gold or ‘Waste’ which has
no economic value. The Ore is sent to a crusher at the side
of the open pit and the Waste rock is used to build the shal-
low sloped embankment for impounding the tailings. Dust
is minimised by continual water spraying and ensuring the
rock is kept in situ during fragmentation, which also assists
the easy excavation and does not use excessive energy.
The conveyor: This is an electrically powered belt con-
veyor that will transport the crushed Ore just over a kilome-
tre to the Processing Plant. The use of a conveyor is the
most energy efficient system available to transport the Ore
and minimises dust. It will not be visible from the villages of
Ilovica and Shtuka.
The Processing Plant: The crushed Ore is ground to
a fine powder and mixed with water to produce a slurry.
Frothing agents and collectors are added that stick to the
copper minerals and these enhance the ‘hydrophobic’
properties of these copper minerals making them attach
themselves to air bubbles. Air bubbles are passed through
the slurry in a series of tanks or cells and a froth forms on
top of the tanks. The froth is skimmed off the top of the
tanks and collected. The collected froth is filtered and forms
a concentrate of copper bearing minerals that contains
around 24% copper metal and some gold. The concen-
trate is sent directly from the Processing Plant to a smelter
in Bulgaria using regular road trucks. This process is called
flotation and is used safely in many locations in the region
and around the world. Water is recovered along with the
reagents. The material left in the slurry once the copper
bearing minerals have been extracted is called the Tailings
and this comprises benign minerals. The tailings are thick-
ened to a wet sand and deposited in the Tailings Manage-
ment Facility. The Process Plant is hidden from view behind
and above the Open Pit.
The Tailings Management Facility: This comprises
an embankment composed entirely of Waste rock which
has no economic value. The embankment has a very shal-
low slope which is very stable and fits in with the slopes of the
natural landscape. These features ensure that it can withstand
even an extremely large earthquake with no breaks so that
the impounded material will stay in place. There will be an
appropriate geotextile liner for the facility. The volume of wet
sand retained by the embankment is less than many water
dams in Macedonia. Over time the wet sand will dry and
at closure can be vegetated as woodland and pasture and
the slopes of the embankment reforested. The Shtuka River
will be redirected around the Tailings Management Facility
to make sure it flows as before and is not in contact with
the tailings facility. The design of the facility also allows for
extreme flood events with no spillage. Water that gathers
on the tailings surface during operation will be used in the
Process Plant. The facility is around two kilometres from
the nearest houses and is partially hidden from view by a
low-lying hill.
Mine Infrastructure Area: This is a small area where
trucks and excavators will be serviced and some offices
and a car park are located.
As part of our responsible operating, a 30 million euro
fund has been set aside for the rehabilitation of the Project
area including
Re-vegetation to forest of the Tailings Facility Embank-
ment; Re-vegetation to forest and pasture of the Tailings
Facility surface.
In addition, rehabilitation of all roads that the community
/ forestry company does not wish to use and removal and
scrap recycling of all machinery and steel work.
Levelling of the plant site- this could be used as a busi-
ness park or re-vegetated according to the local commu-
nity’s wishes. The pit will be allowed to fill to a lake. Any
AmCham Macedonia Magazine
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