When it comes to air quality control, the onus is increasingly on the quarry rather than regulators to ensure best practice is met, according to two environmental experts.
Cameron McNaughton is a principal air quality consultant, while Roger Cudmore is a principal environmental consultant for consulting firm Golder, a member of WSP. They spoke to Quarry
about the assistance and advice firms like Golder can provide to reduce dust and pollutant emissions and improve air quality control in the quarrying industry.
McNaughton and Cudmore emphasised that the consulting process does not stop at any on-site quarry assessment. In fact, the process of inviting communities and authorities to the table is equally important in helping quarries work responsibly.
“There’s an emergence of concerns about silica in the last five years,” Cudmore said. “In quarries, where air quality control was more of a nuisance to be dealt with, you’ve now got increased perceptions and concerns of the health effects associated with potential crystalline silica.
“The real skill of our job is trying to explain things clearly and try to educate as we go, so people understand the issues and can debunk ideas that might be wrong. Our role is to not only give the quarry sound technical advise, but also to disseminate good information about the science in a way that people understand.”
The consultants explained the ways in which Golder actively helps in improving quarrying processes.
“Typically, if we had a new client approach us, we’d do a site walk-through with the site manager. They’d walk us through the process of removing overburden, crushing, stockpiling and give us an opportunity to review their current practices,” McNaughton said.
“We can look at their dust management plan, and if they don’t have one, we can help to develop one that will codify what engineering and management controls they should implement on-site.”
An independent industry – in theory
Cudmore emphasised Golder’s role as an environmental consultant is not to manage the quarrying industry but to educate and encourage it to work responsibly on its own.
“What we can do for businesses is to help them effective good systems and processes to understand the effects and to really drive it from within their operations,” Cudmore said.
“The industry has to drive the monitoring and community engagement themselves. If we did it all ourselves and they just outsourced it all, it wouldn’t work.”
However, as the Golder consultants explained in a previous contribution to Quarry, simply meeting regulatory standards isn’t enough to appease authorities and communities these days.
“In the past, the legislation has been very prescriptive,” McNaughton said. “Now, in some jurisdictions like Victoria, it’s shifting to the concept of a general environmental duty or results-based legislation which says to quarries: ‘You’re the expert in mining these rocks, you tell us – the EPA – what you’re doing to make sure you meet the criteria we’ve set out’.
“This is important because before you could pollute to the limit while being below what the EPA said. Now, there may be instances where you may be below the set limits but you’re still getting complaints from the public.
“The onus is much more on the quarry to demonstrate that they’re implementing best practices.”
McNaughton continued in describing the connection between quarry and consulting firm.
“It’s a partnership. We come in and take a look at your issues. We determine if there’s potential risks involved and if there are, we can help to upgrade controls. At the end of the day, we can verify measurements to show the authorities an operation is now up to scratch.”
The challenges of an invisible enemy
In the past, there were plenty more challenges to retaining air quality control and doing so in an accessible way. The consultants revealed just how these challenges have been dealt with only recently.
“If you look at a manufacturing plant, you can quantify an emission and understand the exposure that causes air quality,” Cudmore said. “But with a quarry, you’ve got excavators, trucks and lots of different means of generating dust. So, from a modelling perspective it’s very tricky to measure.”
McNaughton said the ability to obtain effective measurement tools has increased dramatically, making best practice quarrying far more accessible.
“Prior to five years ago, making any measurements of these types was very expensive – just one indicative monitor at one location would be $25,000,” McNaughton said.
“But now we have much different types of sensors, which may be less than $1000 each, including the solar power and the batteries to run them, and they’re equipped with SIM cards.
“So, we can ring the operation fences with the sensors, and push alerts to mobile phones of managers with different alarm levels.”
The consultants both said they believe these changes in regulation and accessibility are all for the better.
“Ultimately that change in the regulatory approach is a better way for the industry to go about its business and actually engage with the opportunity, instead of hiding behind numbers and regulatory ticks,” Cudmore said.
“It’s been really difficult to get cost-effective monitoring for operations of all sizes. But now this new suite of sensors allows us to be more proactive in managing dust, even for the little guys,” McNaughton said.
A breath of fresh air with the right data