(MERAF) for the Base Metals Smelting Sector - CCME

3.4. Other Current Emissions Information Environmental
Performance Indicators (release per unit of primary
production)
Figure 29 to Figure 35 provide Environmental Performance Indicators (EPIs) for
each substance and each site based on 2000 data. These EPIs describe the air
emissions per unit of primary production (kg of release per tonne of production).
Production data used to calculate each EPI are based on data supplied by
industry and is summarized in Table 3.
While EPIs identify facilities that warrant closer scrutiny, the many reasons for
differences in EPIs from facility to facility should be considered. Differences in
constituents in the feed and in processes are all important in determining
releases and EPI. Feed quality varies widely between smelters and feeds to
custom smelters can be very variable. In addition, the facilities in these sectors
produce different metals. The incoming concentration in the feed material varies
depending on which metal is being produced (e.g., copper concentrate feed is
approximately 30% copper, while zinc feed is approximately 50% zinc). More
material therefore needs processing to produce one tonne of copper product
compared with one tonne of zinc product.
Releases per tonne naturally vary if a facility is a smelter versus a refinery or an
integrated producer versus a standalone facility. An integrated operation has a
higher total production and therefore has a larger denominator versus nonintegrated
facilities.
The EPIs presented in the following pages can be a useful guide for comparison
between facilities or to determine performance over time of a specific facility, but
do not tell everything. For example, as noted by some reviewers, an increase in
production levels with a corresponding increase in the amount of pollutants
released in the environment would not change the EPI. However, the total
loading of pollutants into the environment would increase. In the same manner,
where both quantities decrease accordingly and the EPI is constant, it is not
possible to measure improvement in performance.
111