Ch. 3 Land - Environment Yukon
Ch. 3 Land - Environment Yukon
Ch. 3 Land - Environment Yukon
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Reclamation and Abandonment<br />
When the ore body is exhausted, and a<br />
mining company wishes to abandon<br />
its site, the ultimate goal is to reclaim<br />
the area and return it to a natural state.<br />
All buildings, infrastructure and<br />
equipment must be removed;<br />
recontouring of land, capping or<br />
flooding of tailings, and revegetation<br />
is carried out, depending on the site<br />
requirements and configurations. The<br />
preferred solution is a ‘walk away’<br />
scenario, where the land is revegetated<br />
and no further maintenance is required.<br />
This will not always be possible, and<br />
some mines in the <strong>Yukon</strong> will require<br />
perpetual treatment of waste waters<br />
prior to their release to the receiving<br />
environment. The fragility of the<br />
northern environment makes mining<br />
and reclamation an even more<br />
challenging aspect of mine planning<br />
in the <strong>Yukon</strong>. Proven southern<br />
procedures may not necessarily be a<br />
panacea in the north.<br />
One concern over the past few years is<br />
the lack of a process that ensures<br />
mining reclamation will take place. If a<br />
mine is in production for a number of<br />
years, a reclamation fund is to be<br />
created to clean up and rehabilitate<br />
the site following a mine closure or<br />
temporary shutdown. Under the old<br />
Northern Inland Waters Act, a company<br />
was to set aside a percentage of their<br />
total capital cost per year for<br />
reclamation purposes.<br />
In recent years there have been<br />
changes to regulations that deal with<br />
the environmental impact of mining in<br />
Ketza River Project 1998<br />
the <strong>Yukon</strong>. Now companies must<br />
provide plans and financial guarantees<br />
that ensure reclamation work and mine<br />
abandonment will take place in a<br />
satisfactory manner. If abandonment<br />
is taken into consideration right from<br />
the start, reclamation objectives can<br />
be incorporated into their daily<br />
operations. Overburden, waste rock,<br />
tailings and structures are dealt with<br />
in such a way that their final disposition<br />
is feasible and affordable.<br />
Reclaimed mining areas may be<br />
developed for other land uses. For<br />
example, the City of Whitehorse used<br />
an abandoned open pit from the old<br />
Whitehorse Copper Mine as a solid<br />
waste disposal site for a number of<br />
years. Other feasible post-mining land<br />
use options include improved wildlife<br />
habitats, recreational opportunities, or<br />
other new industrial uses.<br />
While under the <strong>Yukon</strong> Waters Act,<br />
the Water Board may require a reclamation<br />
fund to be established, the<br />
provisions under the Act and Regulations<br />
are discretionary, not mandatory<br />
requirements. In some cases, the<br />
funds accumulated are inadequate to<br />
cover the reclamation costs at the<br />
time of mine closer, as was the case<br />
with the Faro and Mt. Nansen mines.<br />
Hard Rock Mining Properties –<br />
Active Mines<br />
Brewery Creek<br />
Viceroy Resources Corporation’s<br />
Brewery Creek year-round heap leach<br />
gold operation (the first and only heap<br />
leach operation in the <strong>Yukon</strong>) is the<br />
only operating mine in the <strong>Yukon</strong><br />
(1999). The first bar of gold was poured<br />
on November 15, 1996 and the mine<br />
reached full production in May 1997.<br />
Seasonal open-pit mining produces<br />
11,000 tonnes of ore per day between<br />
April and October annually. Eight oxide<br />
deposits were originally delineated at<br />
Brewery Creek with Upper Fosters and<br />
Canadian deposits now mined out.<br />
Five new zones have been explored,<br />
drilled and trenched, expanding the<br />
reserves.<br />
The reclamation of waste rock, minedout<br />
pits and used ore is an ongoing<br />
process at the Brewery Creek mine.<br />
It is easier for reclamation to progress<br />
because ore deposits are mined from a<br />
series of relatively small pits, instead<br />
of from one large area. As each pit is<br />
mined out, it is reclaimed with waste<br />
rock from the next reserve. Backfilling<br />
is the preferred method as it causes<br />
less site disturbance and the pit walls<br />
end up re-contoured, allowing the area<br />
to blend into the original landscape.<br />
In May 1996, an aggressive revegetation<br />
program was initiated in the Canadian<br />
mine area and the clearing below<br />
the leach pad and ponds, using an<br />
agronomic mix called Klondike Valley<br />
seed mix, covering an estimated area of<br />
11 hectares 2. In 1997 reclamation<br />
work was performed on approximately<br />
20 hectares of disturbed land, including<br />
seeding and fertilizing various locations<br />
throughout the site, and recontouring<br />
and re-vegetating the Canadian waste<br />
dump and the West Canadian pit.<br />
Efforts were made to increase the use<br />
of native seed species (Brewery Creek<br />
seed mix) rather than the agronomic<br />
counterparts 3. In 1998 approximately<br />
six hectares of disturbed land in the<br />
mine, leach pad, and access road were<br />
revegetated. Efforts to procure a native<br />
seed mix were continued. Research<br />
We need to get involved with the<br />
mining companies to explain how<br />
we used the land before. After<br />
they finished (with the mine), see<br />
that they put everything back in<br />
place. Not to leave cyanide<br />
behind; that they clean up before<br />
they go away again.<br />
–Roddy Blackjack,<br />
Little Salmon Carmacks First<br />
Nation Elder.<br />
C H A P T E R 3 L A N D ❧ 4 7