A guide to leading practice sustainable development in mining

But are noise levels increasing? The EPA Victoria (EPA, 2007) indicates that noise
across Melbourne hasn’t increased since the 1970s and yet community complaints
have risen considerably. In Britain, noise complaints are five times higher than they
were 20 years ago. It is clear therefore that the community is becoming less tolerant
to noise than it once was.
The issue of dust emanating from a mine site has been the focus of intense media
scrutiny in Western Australia recently. The issue surrounds the export of lead
concentrate from Magellan Metals’ Wiluna mine from the ports of Esperance and
Fremantle. The extent of community dissatisfaction can be seen from newspaper
headlines in November 2008 (Clarke, 2008) – “Unions promise to fight Barnett
over lead shipments” and “Port’s mayor vows to fight risky lead exports” and “Lead
leaches hope of Esperance future”.
These issues are important in all sectors of our industry – coal, metalliferous and the
quarry sector. Indeed, the front cover of “Quarry”, the official Journal of the Institute
of Quarrying Australia in November 2007 headlined “Ensuring your neighbours don’t
eat dust”. The issues are important whether the mine is situated in the Tanami Desert,
the Hunter Valley or a more densely populated area. It is often in the latter situation
where most problems arise. In Australia, these situations are typical of quarries for
construction materials; mines with a residential workforce such as Kalgoorlie, Mt Isa
or Broken Hill or mining fields in locations such as the Hunter Valley where mining is
often not considered the most desirable land use. Of course many Australian mining
companies operate internationally and it is in these countries, where far higher
densities of populations exist in the vicinity of the mines, that the community impacts
of airborne particulates, noise and vibration are exacerbated.
The issue of air blast overpressure has to be well managed if mines are in close
proximity to residential areas. Blast overpressure levels experienced from
operations on open cut mines depend on many factors including the design of the
blast, the distance from the blast to the receiver and the prevailing atmospheric
conditions. The way in which temperature and wind vary along the path through
which the over pressure wave travels from the source to the receiver is particularly
important in determining the overpressure experienced at the receiver. Modelling
allows the effects of atmospheric conditions to be taken into account before
making the decision to blast and ultimately used to predict the enhancement of
blast overpressure levels. The results are presented as contour plots overlaid on
a map of the area surrounding the blast. An example showing blast overpressure
enhancement is provided in the figure below. The results are promising and the
system appears to be a useful tool, in its current state of development, to improve
the management of impacts from blasting (see LP ANCV p.52).
A GUIDE TO LEADING PRACTICE SUSTAINABLE DEVELOPMENT IN MINING 89