standardization of environmental data and information - International ...

The test and reference sites would be small dots, or probably single
lines, just a few square kilometres or a few tens of square kilometres in
area, in contrast to the scale of the mine site, which would cover a few
hundred or a few thousand square kilometres. Thus, environmental data
were needed not only from the test and reference sites, which some had
already investigated and others would study in the future. The lateral
extensions of the mine site also had to be studied, because the
environment throughout the mining area would not be the same as it was at
the test and reference sites. Enough baseline data would have to be
collected throughout the entire mine site, which meant that two lists of
parameters were needed -- one with baseline data needed for many
applications and a separate list for impact assessment.
Reviewing the environmental and mining applications for the
various parameters, Dr. Sharma observed that much of the data collected
at the surface, including productivity, would be of interest for environmental
assessment, but a lot of it would be useful to the mining engineers and
modellers. They would be interested in methods of controlling discharge to
diminish its impact and conserve the surface waters. Temperature profiles,
oxygen levels and other data would be useful for deciding the point of
discharge. Geological data would be useful for the engineers concerned
with mining-vessel design, the stability of the vessel and its operation.
Water-chemistry data would help in predicting the corrosion levels of
underwater systems. The number of operating days, transfer of ore at the
surface and other matters also required environmental input.
In the water column, studies were already underway on currents,
the oxygen-minimum zone, temperature profiles, water chemistry and
particle fluxes, all useful for impact assessment. These would also be
helpful for the mining engineers as they thought about the behaviour of
their pipes under water, leakages, corrosion and the migration of sediment
at the point of discharge.
At the seafloor, environmental assessors were concerned about the
sediment plume, resedimentation, geological and biochemical changes in
seafloor features, and the effect on biomass. Some of these, relating to
seafloor features and others, were of interest in mine-site selection, coping
with obstructions on the seafloor during the operation of a mining system,
the benthic transport of sediment and nodules, and the design of other
mining-system components.
INTERNATIONAL SEABED AUTHORITY 493