Water Pollution and Mining

 There are four main types of impacts on water from mining
from  www.landkeepers.ca

1. Acid Mine Drainage

Acid Rock Drainage (ARD) is a natural process
whereby sulphuric acid is produced when sulphides
in rocks are exposed to air and water.
Acid Mine Drainage (AMD) is essentially the
same process, greatly magnified. When large
quantities of rock containing sulphide minerals
are excavated from an open pit or opened up in
an underground mine, it reacts with water and
oxygen to create sulphuric acid. When the water
reaches a certain level of acidity, a naturally
occurring type of bacteria called Thiobacillus ferroxidans
may kick in, accelerating the oxidation
and acidification processes, leaching even more
trace metals from the wastes.
The acid will leach from the rock as long as its
source rock is exposed to air and water and until
the sulphides are leached out – a process that
can last hundreds, even thousands of years.
Acid is carried off the minesite by rainwater or
surface drainage and deposited into nearby
streams, rivers, lakes and groundwater. AMD
severely degrades water quality, and can kill
aquatic life and make water virtually unusable.

2. Heavy Metal Contamination & Leaching

Heavy metal pollution is caused when such metals
as arsenic, cobalt, copper, cadmium, lead,
silver and zinc contained in excavated rock or
exposed in an underground mine come in contact
with water. Metals are leached out and carried
downstream as water washes over the rock
surface. Although metals can become mobile in
neutral pH conditions, leaching is particularly
accelerated in the low pH conditions such as are
created by Acid Mine Drainage.

3. Processing Chemicals Pollution

This kind of pollution occurs when chemical
agents (such as cyanide or sulphuric acid used
by mining companies to separate the target mineral
from the ore) spill, leak, or leach from the
mine site into nearby water bodies. These chemicals
can be highly toxic to humans and wildlife.

4. Erosion and Sedimentation

Mineral development disturbs soil and rock in
the course of constructing and maintaining
roads, open pits, and waste impoundments. In
the absence of adequate prevention and control
strategies, erosion of the exposed earth may
carry substantial amounts of sediment into
streams, rivers and lakes. Excessive sediment
can clog riverbeds and smother watershed vegetation,
wildlife habitat and aquatic organisms.

So you see that some commenters in online  publications have spun the fact that there is a natural eroded way of very slowly leaking some pollutants into creeksby making it seem that this is equal to what mining does. But it is the large scale mines that expose huge amounts of metals and minerals to oxygen and water that cause vast amounts of pollution in our lakes and streams.

And to Arbitrarly fill a native fish bearing lake with byproduct  pollutants is utterly assinine
There can be no other conclusion to this ruination of the Taseko, Chilco, Chilcotin, and Fraser watershed than the pursuit of the almighty dollar at the expense of your health and the loss of a pristine fish bearing and spawning area of this Province.

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