The Aggregate and Quarry Association has fired a public relations salvo at Environment Canterbury’s (ECAN) proposal to bring in a ‘no tolerance’ ban on any dust beyond a quarry’s boundaries.
AQA chair Brian Roche says for ECAN to announce a ‘no tolerance’ approach to any dust of any kind beyond a quarry boundary beggars belief.
The move would impact on a whole range of land-based activities, he says, not just the quarrying industry, which already takes health issues presented by potential exposure to higher levels of Respirable Crystalline Silica dust seriously, as a matter of course.
This followed a comprehensive air monitoring programme around Yaldhurst quarries given concerns from residents about potential exposure to mined silica dust, jointly announced by ECAN, the Canterbury DHB and Christchurch City Council.
Brian Roche says the quarry industry is very willing to share its scientific advice on dust issues and to work with local authorities to address any consent issues which may arise from dust control at any quarry.
“We can understand residents’ concerns about dust including silica dust. Silica itself has been estimated to make up 12 percent of the Earth’s crust. However, not all silica dust is respirable crystalline silica, which is subject to a strict NZ WorkSafe standard.”
Roche points out that since dust is a factor in quarry operations around the country, operators already work with local authorities and neighbours to have best practice controls including spraying water over truckloads of aggregate leaving a quarry, wheel baths and planting shelter belts.
“We acknowledge that respirable crystalline silica dust at certain levels can potentially present risks to staff working at quarries. Many quarries, particularly larger operators, conduct regular health and respiratory monitoring of their staff and I’ve not been made aware of any particular, pressing health concerns.”
Roche adds that our workplace standard for respirable crystalline silica is below 0.1 milligrams per cubic metre of air volume over an eight hour average.
“If there is any evidence of that level being exceeded and a quarry worker being exposed, we’d expect authorities to respond.
“That said we have spoken to our Australian and European counterparts in the quarry industry and they are unaware of any issue ever arising with neighbours being exposed to respirable crystalline silica.
“For ECAN to now announce a ‘no tolerance’ approach to any dust of any kind beyond a quarry boundary just beggars belief.”
“Quarries are like other land-based activities including farming, sub-divisions, forestry and road works. When a howling nor-wester blows, you will have some dust no matter what controls you put in place. Whether there’s any respirable crystalline silica in it is another matter and that is not supported by evidence we are aware of here or overseas.”
If ECAN’s ‘no dust beyond the boundary’ edict prevails, it won’t just be quarries that are shut down.
“Farmers won’t be able to farm if there’s ever any dust caused. Canterbury’s building programme will draw to a halt because earthworks inevitably create some dust. ECAN itself will have to stop river protection work because there’ll be some dust in extracting the rocks and later repositioning them on river banks.”