Community members have raised concerns about the impact of large scale developments on air quality in the Namoi region. The community is keen to access air quality data to understand the current situation and for this data to be used as a baseline for the future.
What is being measured and reported
Ambient concentrations of particulate matter (PM), including PM2.5 and PM10, are continuously measured at four monitoring stations (Werris Creek, Breeza, Wil-gai and Maules Creek) using the Tapered Element Oscillating Microbalance (TEOM) instrument. You can find more information about PM and TEOM instruments on the OEH web site.
Local coal mining companies report monitoring results to the EPA weekly, which includes records of 1-hour and 24-hour rolling average PM2.5 and PM10 concentrations in ambient air at each of the four monitoring locations. The weekly reports include
- the monitoring station location - a descriptive location and map coordinates
- the monitoring station details - instrument type and operating standards
- the monitoring data period and summary - timeframe, number and proportion of valid results
- detailed monitoring data - 1-hour and 24-hour rolling average PM2.5 and PM10 concentrations
- a summary of quality assurance and quality control – outcomes of checks performed to determine whether the data is valid or invalid
The data provides an indication of PM2.5 and PM10 contributions from all sources throughout the Namoi region including
- unpaved roads
- dust storms
Responses and trends in these data cannot be attributed to any one of these sources without additional supporting investigations.
Interpreting the monitoring results
The National Environment Protection (Ambient Air Quality) Measure (Ambient Air Quality NEPM) includes a 24-hour clock average
- standard for PM2.5 of 25 µg/m3
- standard for PM10 of 50 µg/m3.
The Ambient Air Quality NEPM also establishes annual average standards for PM2.5 and PM10. Ambient quality data on this web page as part of the NRAQMP cannot be compared to these criteria, as the data is not averaged over the required 12-month period.
The Ambient Air Quality NEPM PM standards act as benchmarks against which ambient air quality can be assessed at specifically nominated monitoring stations to give an average representation of general air quality and population exposure (that is, 25,000 people or more). These sources do not, however, apply specifically to monitoring and managing localised impacts from sources like heavily trafficked roads or large industries.
Find out more about the applicability of the Ambient Air Quality NEPM in the Revised Impact Statement.
The four monitoring stations (Werris Creek, Breeza, Wil-gai and Maules Creek) are not used to determine compliance of individual premises with the Ambient Air Quality NEPM standards. Rather, these were established to
- provide background ambient air quality data
- help assess any impacts on local communities
- assist in on-site management practices
- manage cumulative impacts
It is not appropriate to evaluate 1-hour clock average PM2.5 and PM10 concentrations against the Ambient Air Quality NEPM standards. However, evaluating the 24-hour rolling average PM2.5 and PM10 concentrations against the Ambient Air Quality NEPM standards may provide a useful guide about how air quality in the Namoi region compares with other locations across NSW.
Accessing monitoring results
View the ambient air quality monitoring data for 1-hour clock and 24-hour rolling average PM2.5 and PM10 concentrations at each monitoring station. All stations monitor PM2.5 and PM10 emissions.