Mining in focus
The maps generated by the mine surveyors for underground mining operations will
contain the details and the location of underground drill holes in the mine.
usually country specific or can be a
combination, such as international
standards like WGS84, or a local
datum such as the Cape datum in
South Africa.
The beacon used as base for the
survey needs to be built correctly, as
this will influence all measurements
taken f rom that point. An incorrectly
installed beacon will invalidate
all the data generated f rom it.
Incorrectly installed survey pegs
in the hanging wall will embed an
incremental error in all subsequent
surveys f rom that point.
Underground mine surveying
The maps generated for underground
mine operations are a general plan
of any underground levels to a scale
that is in accordance with good
engineering practice and shows, as far
as practicable, the true size and shape
of all development openings. The plan
will contain details and the location of
underground drill holes in the mine.
It will also indicate services, such as
electrical power cables, compressed air
lines, or diesel fuel lines and explosives
bunkers. It also indicates the position
of underground infrastructure,
including conveyor belts, workshops,
silos, and crushers. The mine plan
further contains longitudinal sections
or projections to a scale that accords
with the mine’s code of practice
and shows all underground mining
operations. The cross-sections or
projections need to be on a scale that
shows the ore bodies and mined-out
parts of ore bodies.
In underground operations, the mine
survey measures the areas and the
volumes blasted by the underground
crews at a certain measuring interval,
as required by the operating standards.
In the case of outsourced mining, the
survey will measure the quantity of
work completed during the contract
invoicing period and calculate the
contractual earnings. The data is also
primarily used to calculate production
from the mining operation. The
volume of the stockpiles and the waste
dumps accumulating on the surface
of the mining property and stowed
underground as waste or low-grade
material, also needs to be measured.
The underground mine survey
data is fed into the mine plan and
designs. Based on the results, the mine
schedule for the next month, three
months, six months, year, and five-year
plans can be adjusted. The data is used
by the mine planners and schedules
in the reconciliation of planned and
mined tons in a given period.
The mine survey department works
closely with the geology and rock
engineering departments. Survey data
is used to determine the position of
faces sampled and distance mined as
well as proximity to known areas of
geological features, such as faults or
dykes that would result in geological
mining losses. The surveyors assist in
the pegging of boreholes by surveying
the collar position — the accuracy has
an influence on the accuracy of the
geological block model.
The environmental department also
depends on these inputs, particularly
for ventilation designs. The maps
generated assist in the health and
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