quarry dust in a changing world · quarry dust in a changing world craig beyers manager consulting...

Quarry Dust in a Changing WorldCraig Beyers

Manager Consulting Services, Assured Monitoring Group

Unit 7, 142Tennyson Memorial Avenue – Tennyson – Queensland – 4105 Phone: 1300 662 495 – Email: [email protected]

• Past 12 months has seen increased focus on dust in quarries and extractive industries.• Two parliamentary enquires

• Review of Worksafe Australia Exposure Standards

• Amendment of the Ambient Air Quality National Environment Protection Measure

• Regulatory changes and increased interest represent sources of uncertainty for the quarrying industry

• New technology is leading to better management

20/10/2017Craig Beyers Assured Monitoring Group Pty Ltd

• Conventionally taken to refer to all particles with an aerodynamic diameter less than 75 µm.

• Comprises both natural and anthropogenic sources of varying sizes, chemical composition and toxicities.

• Varies significantly both temporarily and spatially dependent on the sources of emissions, atmospheric conditions and local topography.

• Not all dust is equal with some sources representing greater risk in terms of health and nuisance impacts.


• Impacts differ depending on size, type and chemical composition.

• Therefore, a single concentration limit is unable to adequately protect for all dust sizes, types and sources.

• Understanding these differences and their impacts to the management of quarry dust is essential.


Type of Dust Time Weighted Average (mg/m3)

Inhalable Dust 10

Respirable Dust 5

Crystalline silica (including quartz, cristobalite, trydimite) (respirable dust) 0.1

0.1


20/10/2017Craig Beyers

Source: Plumlee and Ziegler 2006

Assured Monitoring Group Pty Ltd

• On many sites, the presence of visible dust is used as an indicator of dust management performance.

• In reality, the visibility of dust is complex and depends on a number of factors.

• A visible dust cloud may represent a hazard, however, the absence of a visible plume does not represent “safe” conditions.

• No safe level of dust.


Type of Dust Time Weighted Average (mg/m3)

Inhalable Dust 10

Respirable Dust 5

Crystalline silica (including quartz, cristobalite, trydimite) (respirable dust)

0.1


Type of Dust Averaging Period

Maximum Concentration

Standard

Maximum Allowable

ExceedencesPM10 1 day

1 year

50 µg/m3

25 µg/m3

None

None

PM2.5 1 day

1 year

25 µg/m3

8 µg/m3

None

None


Type of Dust Averaging Period

Maximum Concentration

Standard

Maximum Allowable

ExceedencesPM2.5 1 day

1 year

20 µg/m3

7 µg/m3

None

None



0

0.005

0.01

0.015

0.02

0.025

0.03

0.035

0.04

Emis

sio

n F

acto

r kg

/to

nn

e

• Managing dust from a quarrying activity is not easy and takes considerable financial outlay and effort.

• An informed decision requires a clear understanding of the risks of uncontrolled (or status quo) emissions for both workers and nearby residents

20/10/2017Assured Monitoring Group Craig Beyers

Source: Hedges, 2016

• Workplace health and safety legislation requires quarry operators to understand and assess the risks to workers health and safety.

• Generally requires monitoring regularly enough to provide a reliable assessment of risk.

• Environmental sampling requires larger sample volumes to allow analysis to meet the require detection thresholds.

• Numerous factors influence representativeness of samples including quarry operations, meteorology, placement of monitoring equipment.

20/10/2017 Assured Monitoring Group Pty LtdCraig Beyers

• Numerous options already available on the market to monitor air quality in real-time.

• Regulars both in Australia and overseas experimenting with technology.

• Through the IoT, manufactuerers are ffective ways of identifying key sources of dust, activities requiring further attention or the effectiveness of on-site controls.

• Typically, undertaken by experienced consultant and using real-time monitoring device to determine where dust emissions are generated.

• Monitoring data can be used to gain understanding of effectiveness of current controls.

• Can also provide information about worker exposure in individual work areas.

20/10/2017Assured Monitoring Group Pty Ltd

Craig Beyers

• Effective ways of identifying key sources of dust, activities requiring further attention or the effectiveness of on-site controls.

• Typically, undertaken by experienced consultant and using real-time monitoring device to determine where dust emissions are generated.

• Monitoring data can be used to gain understanding of effectiveness of current controls.

• Can also provide information about worker exposure in individual work areas.


• Useful for testing overall effectiveness of control options.

• Generally requires assumptions to be made about operational and physical features of the quarry.

• CRAP IN = CRAP OUT

• Generally assess impacts of upper bounds of impacts through a worst-case production scenario.


20/10/2017Assured Monitoring

Group Pty LtdCraig Beyers

• Relatively low cost

• Allows operator to manage dust management activities based on conditions and risk of impacts.

• Can be used to automate control activities (e.g. sprinkler operation).


• Able to provide greater resolution on extent of potential impacts.

• Through coupling with monitoring data, able to provide an understanding of the accuracy of the simulations.

• Can be used to automate control activities (e.g. sprinkler operation).

• Process is well underway - new exposure standards expected in 2018.

• Respirable dust limit could reduce.

• For crystalline silica, change in exposure limit more likely (OSHA recently adopted limit of 0.05 mg/m3)

Revised Occupational Exposure Standards

• For PM2.5, recent changes to Ambient Air Quality NEPM saw the establishment of a long term objective.

• Likely future state regulations will seek to adopt this.

• Recent NEPM variation also removed previous 5 allowable exceedences per annum.

Environmental Dust

• Overall increased focus on dust emissions and, in particular, chemical composition of dust.

Community and Regulator Focus on dust

• Increased expectation of real-time information about impacts.

IoT Influence on Expectations


quarry dust in a changing world · quarry dust in a changing world craig beyers manager consulting...

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