From: James Rogers (jamesr@best.com)
Date: Wed Jun 06 2001 - 13:42:38 MDT
Anne Marie Tobias wrote:
>The mining industry has struggled (read paid off politicians by the
>boat load) to make sure that no changes have been made mining
>laws since the time of the Pony Express (which pretty much means
>anything goes... if you're willing to stake a claim, you can do what
>you please.)
I have to ask you to cite sources. I have a lot of personal knowledge of
the gold mining industry, both at the political/industrial level, and at
the technical level as well. You are making claims that are easily
verifiable as false. What do you know about the actual requirements and
regulations regarding mining claims? It appears very little.
>The results are that an investment firm comes in, they
>build a huge shallow cyanide lake. They fill it with rediculously
>poor gold ore. They then process the cyanide solution to extract
>the gold. This is only economical if done on an immense scale.
>The side effect is that they produce a superfund site that will cost
>tax payers billions of dollars to clean up.
This is incorrect. They are not using "ridiculously poor gold ore". In
the 19th century and prior, the primary means of extracting gold from ore
was with mercury, which had the advantage of being relatively easy to do
with very low tech. The disadvantage was that the extraction efficiency
was relatively poor (low 90s percentage-wise), never mind the environmental
problems with using mercury this way. Fast forward to the 20th century and
all gold ore is processed using the much cleaner and more efficient, if
more complicated, cyanide extraction process which gives good extraction
results (high 90s percentage-wise). This means that mine tailings from the
mid-19th century, some of which were extraordinarily rich ores by today's
standards, can themselves be re-processed for a yield that is roughly 5% of
the original ore body. And since the ore has already been mined and
processed once, the overall cost of obtaining the gold is substantially
less as well. Most gold produced today comes from this or microscopic
hydrothermal ores rather than the nuggets and veins (long since played out)
that most people associate with gold mining.
Cyanide extraction on most ores is done in reactor vessels, because it is a
reactive ion that will only stay useful in chemical environments that have
an extremely high pH. If you simply dumped it in a lake, it wouldn't last
very long at all, as it chemically reacts very easily and is susceptible to
UV degradation in many forms. I am aware that sometimes cyanide solution
is used to concentrate gold in the bottom of ore heaps; you douse a giant
ore heap with cyanide solution, and while the cyanide doesn't last very
long, it lasts long enough to migrate gold atoms toward the bottom of the
heap. Lacking any real pH controls, you'll end up with very little cyanide
running freely at the bottom. If anything dies from sitting in the pond,
it would probably have as much to do with toxic metal exposure as it does
with residual cyanide. And even if there was any cyanide in the pond, it
would be quite cheap to bind it into a harmless form.
Quite frankly, the water in many gold mining areas is nasty and toxic by
the nature of the geology of areas with gold concentrations; both from
natural heavy element contamination and from very high natural acidity
(such as in the U.S. gold mining areas). I wouldn't go swimming in *any*
pond in these areas that hadn't been tested for serious natural metal
contamination. I know that in the U.S. gold mining areas, some of the
natural ponds have arsenic levels that are several orders of magnitude
higher than anything people are allowed to produce, and sulfuric acid is
mined from natural springs. The earth is not benevolent. Many things
attributed to mining (in the U.S. at least) existed long before the
mines. I'm not saying that mines don't sometimes create a mess or that
they shouldn't clean up their mess, but the mess created by mining is
highly over-stated in many cases. Or at least the cases that I am familiar
with (the Great Basin mining region).
>That's a cynical,
>self serving business... it damages the world and it screws the
>public, and makes a very few people moderately wealthy.
Actually, gold mining is a relatively meager income for most people, and
the single most common occupation in many gold producing regions. Very few
people get wealthy mining gold these days. In these regions, the public is
served very well by mining. The only people who complain about it are
bored city-dwellers who continue to consume the metals mined in vast
quantities and have never visited the regions in question.
-James Rogers
jamesr@best.com
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