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Fugitive emissions, which by 1976 will consti-
tute the major dust problems (over 95%) can be slightly
reduced by covering trucks with tarpaulins and/or wet-
ting loads. Unless this is also applied to waste
dumping the reduction is not considered to be signifi-
cant. It is therefore felt that ''dump dust'' and mining
operation (blasting, shovelling) dust losses are some-
thing the industry and government must accept as normal
under present economic conditions.

As far as gaseous pollutants are concerned,
efficient combustion of fuel coupled with selection of
fuel with low carbon residue and sulphur content is the
desired method of maintaining low pollutant levels. If
outmoded burner types are used, the other course of
action is to install thermal incinerators (afterburners)
or scrubbing devices to the exhaust stacks. This is
expensive.

V. MONITORING
he EMISSIONS

At the Cassiar, B.C. operations no source emission
monitoring has yet been performed as it is relatively
expensive and to date has not been required. As earlier
stated, the Pollution Control Branch may soon require a
monitoring program for our ?lantsite Emissions. Such a
program would probably ask for particulate and gaseous
analysis information, and may be done by consultants (if
only a few samples are required) or by our own Environ-
mental Department (once the equipment is purchased.)

Methods for sampling are discussed in detail in
available literature. Sampling holes are normally drilled
in each stack, to allow multi-axis probe traverse with an
isokinetic sampler. Sample gas is drawn through a probe
tip (heated in wet applications) at about the same velocity
as stack yas is travelling by the probe. The sample passes

through the sampling train, which is a series of filters,
cyclones, and collection media, the specific components

dependent on the application. In the case of particulate,
the solids would be collected on a 0.3 micrometer pore
glass fibre filter (preweighed). In the case of common

gaseous pollutants, the sample gas would be bubbled through
chemical reagents.