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This article maps dust control onto the disclosures mines are actually asked to complete, looks at where water-based suppression makes those numbers harder to move, and sets out what typically changes when the road surface itself is stabilised.

For a long time, dust was treated as a housekeeping matter. A road got dusty, a water truck went out, and the issue was considered closed until the next shift.

That framing has narrowed. Dust generation touches at least four areas that now sit inside formal reporting: water withdrawal and consumption, air emissions, community impact and, on tailings facilities, surface stability. Each of those has a disclosure attached to it, and each of those disclosures is read by someone outside the operation.

The practical consequence is that a decision about dust control is no longer only a decision about roads. It is also a decision about numbers that appear in an annual report, are compared against peers, and are increasingly assured by third parties.

This does not mean dust control has become a compliance exercise. It means the same intervention can now be justified twice: once on operating cost, and once on reported performance. Understanding which disclosures are affected makes it easier to build that case internally.

Water is where the link is most direct, because water-based dust suppression consumes water that has to be withdrawn, accounted for and reported.

Under GRI 303: Water and Effluents 2018, three of the five disclosures are quantitative: 303-3 water withdrawal, 303-4 water discharge and 303-5 water consumption. All three require a breakdown for areas with water stress. Disclosure 303-5 asks explicitly for “total water consumption from all areas with water stress in megalitres”. Water applied to a haul road is consumed, not discharged, and in an arid region it is consumed in exactly the category that receives the most scrutiny.

The industry guidance points the same way. The ICMM Water Reporting: Good Practice Guide (2nd edition) asks companies to present water metrics twice: aggregated for all sites, and separately aggregated for all sites situated in water-stressed areas. A site in a dry region therefore contributes to a figure that is deliberately isolated so it can be examined on its own.

That matters because of where mining tends to operate. The World Resources Institute found that at least 16% of critical minerals mines and deposits sit in areas already facing high or extremely high water stress, with a further 8% in arid or low-water-use areas, and projects a rise towards 20% by 2050 under business-as-usual conditions.

In Australia, the scale of use is well documented. The Australian Bureau of Statistics recorded 749 gigalitres of water consumed by the mining industry in 2023-24, around 4.4% of national water consumption and a decrease of 7.7% on the previous year. Water use is being measured, published and trended, and the direction of travel is expected to continue.

Major operators have attached targets to this. Fortescue reports a target that at least 80% of water withdrawn at Cloudbreak and Christmas Creek is used operationally or for environmental purposes, and reported 94% for FY25. Once a target of that kind exists, every recurring water demand on site becomes a candidate for review, and road watering is one of the most visible.

We have written about the operational side of this separately in need to reduce water consumption? Start with dust control.

The measurement problem most sites hit first

There is a measurement problem worth flagging early. On many sites, water applied to roads is not metered as its own stream. It is drawn from the same source as processing or camp supply, loaded into trucks, and disappears into a general operational figure. That makes it difficult to state a road-watering baseline, and without a baseline any later reduction is difficult to evidence.

Sites that want dust control to count in their reporting usually have to close that gap first. In practice that means recording fill events and volumes per truck, or metering the fill point, so that road water becomes a line that can be trended. It is a small piece of work, but it is the difference between “we believe water use fell” and a figure that can survive assurance.

The second link is particulate matter, and it is more explicit than many teams expect.

GRI 305: Emissions 2016 covers significant air emissions in Disclosure 305-7. Alongside NOx, SOx, persistent organic pollutants, volatile organic compounds and hazardous air pollutants, particulate matter is named as its own category. Dust from haul roads, stockpiles and tailings surfaces is not a side effect that sits outside the framework. It is one of the listed items.

Australian ambient standards give that number a reference point. The National Environment Protection (Ambient Air Quality) Measure sets PM10 at 50 µg/m³ over 24 hours and 25 µg/m³ annually, and PM2.5 at 25 µg/m³ over 24 hours and 8 µg/m³ annually. A non-binding goal for PM2.5 of 20 µg/m³ over 24 hours and 7 µg/m³ annually applies from 1 January 2025.

International guidance is tighter again. The WHO global air quality guidelines updated in 2021 recommend PM10 of 15 µg/m³ annually and 45 µg/m³ over 24 hours, and PM2.5 of 5 µg/m³ annually and 15 µg/m³ over 24 hours. Those values are not regulatory limits in Australia, but they are the benchmark stakeholders increasingly cite when they assess whether an operation is performing well or merely performing legally.

The contribution of mining to reported particulate emissions is significant. Analysing National Pollutant Inventory data for 2008 to 2018, Hendryx and colleagues calculated that coal mines contributed 42.1% of national PM10 air emissions from NPI-reporting facilities. That figure covers reporting facilities rather than all Australian sources, and it is the authors’ own calculation from the raw data rather than an official NPI statement, but it indicates how visible mining is within the reported inventory.

If PM10 is a number your site tracks, the road surface is one of the few places where it can be influenced continuously rather than episodically.

Why haul road dust behaves differently from a stack

The reason is the nature of the source. Emissions from a stack or a plant are a point source: they are contained, ducted and comparatively straightforward to measure and treat. Haul road dust is a fugitive source spread across kilometres of running surface, generated by every pass of every vehicle, and strongly influenced by weather. It cannot be captured at a single point, which is why treating the surface is one of the few levers with continuous effect.

That also shapes how it is monitored. Deposition gauges record what settles over a period and are useful for boundary and community reporting, while continuous PM monitors capture short-term peaks that align with production activity. The two answer different questions, and a dust control change that is expected to affect reported emissions should be matched to whichever measurement the site actually reports against. Agreeing that before a trial starts avoids the common outcome where an improvement is visible on the road but cannot be demonstrated in the data.

It is worth being precise here, because tailings and dust are often bundled together in marketing material in a way the standards do not support.

The Global Industry Standard on Tailings Management, published in 2020, does not contain explicit requirements on dust, air quality, wind erosion or vegetation cover. What it does contain are requirements that surround the issue: Requirement 5.3 on water balance models and water management plans, Requirement 5.6 on progressive closure and reclamation, and Requirement 15.1 on disclosure of environmental monitoring results.

So the accurate statement is not that GISTM obliges an operator to control dust on a tailings storage facility. The accurate statement is that dust on a TSF surface is captured through other routes: the air emissions disclosures described above, site environmental approvals and monitoring conditions, community complaints, and the water management and closure planning that GISTM does address.

That is still a meaningful set of pressures. A dry tailings surface releases fines, loses material to wind, and complicates progressive rehabilitation. The practical considerations are set out in 4 things to consider for tailings dust control, and one applied example is described in transforming dust management at Rosh Pinah Zinc Mine’s TSF.

The environmental column is easier to quantify, but the social column is often what drives urgency.

Dust travels. Where an operation sits near a town, a road or agricultural land, dust is the impact that residents experience directly and repeatedly. It is also the impact most likely to generate a complaint record, and complaint records are frequently reportable.

On site, the safety dimension is documented by regulators. WorkSafe WA’s safety bulletin on traffic management names visibility issues caused by dust among the factors in collisions between heavy and light vehicles on mine roads, incidents that have resulted in serious injuries and fatalities in the Western Australian mining industry. The NSW Resources Regulator has separately flagged an increase in heavy vehicle rollovers where poor ground conditions contributed.

Road surface condition and dust generation are linked, so an intervention that improves one can contribute to the other. That is a supporting argument rather than a guarantee, and it is worth presenting it that way internally.

This is the area where language matters most. Dust control can contribute to supporting a social licence to operate. It does not secure one. Communities assess an operation on a long list of factors, and overstating what a surface treatment delivers tends to undermine credibility rather than build it. We looked at the risk side of this in is dust control risking your licence to operate?

Here is the tension at the centre of this topic. The default response to dust is water, and water is precisely what several of the targets above are trying to reduce.

Water-based dust suppression works while the surface is damp. In hot, dry, windy conditions the surface dries quickly, dust returns, and another pass is required. The cycle repeats through the shift. The result is a control method whose effectiveness is temporary by design and whose consumption is continuous.

That creates several effects at once:

• Water consumption stays high in exactly the sites where water-stressed reporting applies.
• Water trucks occupy haul road capacity, interact with production traffic and add cycle time.
• Truck movements consume fuel and generate emissions that are themselves reportable.
• Repeated wetting and drying can work against surface stability rather than for it.

What repeated wetting does to the road structure

The last point is the one most often missed. A haul road relies on a graded mix of coarse and fine material, with the fines binding the structure together. When the surface dries, those fines are lost as dust, the remaining particles move against each other, and defects develop. Watering treats the symptom, and overwatering can create its own problems, which we covered in one of the biggest mistakes on haul roads is overwatering.

None of this means water has no role. It means that a strategy built solely on water tends to hold two of your reported metrics in tension: the dust number improves briefly while the water number does not improve at all. A wider comparison of the available approaches is set out in your guide to dust control methods, and the specific limits of water are examined in 70% of WA mines rely on plain water for dust control.

The alternative is to treat the surface rather than the symptom, so that fines stay bound into the road structure instead of leaving it as dust.

Bio-cementation is one route to that. The process uses naturally occurring biological activity to form mineral bridges between particles, producing a bio-cemented surface layer that holds fines in place. Terrabind™ applies this principle to haul roads and tailings surfaces, and the underlying approach is described in more detail under what we do.

For reporting purposes, the relevant difference is that a stabilised surface changes the baseline rather than the frequency of intervention. Instead of restoring a damp surface several times a day, the objective is a surface that resists dust generation between treatments.

Where that is achieved, several reported figures can move in the same direction:

• Water withdrawal and consumption for dust control can fall, which is the figure GRI 303-5 and the ICMM water-stressed aggregation ask for.
• Particulate emissions from the treated area can decrease, which is relevant to GRI 305-7 and to site air monitoring.
• Fewer water truck movements can reduce fuel burn and associated emissions.
• A firmer, smoother running surface supports road stability, which has both maintenance and safety implications.

Each of these is a “can”, not a “will”. Results depend on material type, traffic loading, climate, application rate and maintenance practice. What can be said is that the mechanism addresses the cause of dust generation rather than masking it, which is why the effects tend to appear across several metrics at once rather than in one.

What stabilisation does not fix

It is worth being equally clear about what surface stabilisation does not do. It does not remove the need for road maintenance, and it does not compensate for an underlying road that was built with unsuitable material or inadequate drainage. A treatment applied over a structurally poor road improves the surface it is given; it does not rebuild what sits beneath. Nor does it eliminate every dust source on site, since crushing, stockpiles, drilling, blasting and wind erosion on exposed areas each have their own causes and their own controls.

Presenting it accurately matters for the reporting case as much as the technical one. A claim that one treatment resolves site-wide dust invites challenge and tends to collapse under the first audit question. A claim that treated haul roads and treated tailings surfaces show reduced dust generation and reduced water demand is narrower, defensible and still material.

Numbers are only useful with a project attached, so these are stated with their sources.

At Eramet’s Grande Côte Operations in Senegal, road water usage was reduced by up to 85% following a change to a biological dust control approach. The details are documented in Eramet’s GCO reduces road water usage by 85%.

At an ArcelorMittal iron ore operation, water use on haul roads was reduced by up to 75%, described in ArcelorMittal cuts water use on haul roads. A mining service manager at that site reported reducing water trips from three or four times a day to once every few days, with better road durability, less equipment wear and fewer operational interruptions.

At Dangote Cement, water consumption was reduced by up to 70%, set out in Dangote Cement reduces water consumption by 70%.

These are individual project results, not a standard that transfers automatically to another site. They do, however, illustrate the order of magnitude available where conditions suit the approach, and they are the kind of evidence a sustainability team can trace back to a named operation rather than a generic claim.

Where the evidence stops

It is equally important to be clear about what is not established. There is no credible published figure for the share of a mine’s total fresh water that goes to dust suppression, and the percentages circulating on supplier websites do not withstand checking. The same applies to widely quoted figures on tyre life and road condition. Where a number cannot be traced to a project or a study, it is better left out of a report than defended later.

There is a structural reason dust control often underperforms as an ESG lever, and it has little to do with the technology.

The cost of dust control usually sits in an operations or road maintenance budget. The benefits are spread across several owners: water sits with environment, particulate emissions with environment or approvals, cycle time and fuel with production, tyre and component wear with maintenance, community complaints with external affairs, and the reported figures with sustainability. The team that pays sees one line of cost, while the value lands in other people’s numbers.

The predictable result is that a change is assessed narrowly, on cost per litre or cost per square metre, and compared against water that is treated as effectively free because it is already being pumped. Assessed that way, almost nothing beats water.

Agreeing the metrics before the trial, not after

A more complete assessment brings the other owners into the evaluation before the trial rather than after it. In practice that means agreeing in advance which metrics will be tracked, who owns each one, and what the baseline is for each. Water volumes applied to the treated section. Dust or PM readings against the site’s existing monitoring. Water truck hours and fuel. Maintenance and grading intervals. Any complaint or safety records tied to the treated area.

None of this requires new instrumentation in most cases; it requires deciding beforehand which existing data will be pulled and by whom. Sites that do this tend to reach a decision faster, because the argument is settled with their own numbers rather than with a supplier’s brochure. Sites that skip it often finish a technically successful trial that no one can convert into a business case.

If dust control is going to carry weight in your reporting, the assessment needs to cover more than application cost.

Which disclosures does this actually affect? Map the intervention onto the specific line items your organisation reports: water withdrawal and consumption, water in stressed areas, particulate emissions, community complaints, safety incidents. If a supplier cannot help you locate their product in that map, the ESG argument is being asserted rather than made.

What is the evidence behind each number? Ask which site produced the result, over what period, under what conditions and who measured it. Project-specific evidence with a named operation is worth considerably more than a range with no attribution.

What is the full life cycle? Consider application rate, reapplication frequency, maintenance demand, water required during application, behaviour at closure and rehabilitation, and the upstream footprint of the product itself. A treatment that reduces water on site but carries a heavy upstream footprint may not improve the overall position.

How does it behave across seasons? Wet and dry season demands differ, and a method that performs in one may not perform in the other. We looked at that in should your dust control strategy change for wet vs dry season?

Can the result be verified? If a figure is going into a report that may be assured, it needs a measurement method behind it. Agree at the outset what will be measured, how, and against which baseline.

Dust control will not carry an ESG programme on its own. It sits alongside energy, emissions, tailings governance, biodiversity and community investment. What makes it worth attention is that it is one of the few areas where a single operational change can show up in water, air quality, safety and community metrics at the same time, and where the operating case and the reporting case point the same way.

If you want to work through what that would look like for a specific site, the approach is described under responsible mining, or you can get in touch to discuss conditions at your operation.

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