Workers at the
rotary kilns in Khaidarkan often do not wear
any respiratory protection. This is
of concern to worker
health because the kilns are not well-sealed
and so may emit high
levels of mercury vapour to the atmosphere.
The poor seals can
also allow hazardous liquids to leak onto
the flor of the
smelter building. The exhaust gases from the
condenser are vented through a
chimney, and it is important
to ensure their temperature does not
exceed 30°C to prevent mercury escaping. It
was estimated that over the last
few years the kombinat emitted about 3.5
tonnes of mercury annually. The mercury
levels and other contaminants in
slag, sludge (waste from the kilns)
and tailings (waste which
has been treated with |
|
chemicals but
not heated) are high
enough to pose a risk to local people and
the environment.
In its working life the Khaidarkan mine is
estimated to have
produced more than 36,000* tonnes of
mercury. Mercury production was
understandably modest in 1941, at under 100
tonnes, and peaked in the late 1980s
at almost 800 tonnes.In 2008, Kyrgyzstan
produced less than 300 tonnes.
____________________________________
*Apart
from Khaidarkan, historically there were two
other mercury mining sites in the region, Chonkoy and Chauvay,
which produced 9,000 tonnes
of mercury before closing in the early
1990s. |
