An assessment against Victoria’s air quality objectives and goals is shown in the 2012 data tables (PDF 692KB)
In Melbourne the general air quality was good overall. Major impacts on air quality during the year were associated with particles from local dust and urban emissions (particularly from motor vehicles and wood heaters) that were trapped in calm, highly stable conditions.
Particles as PM10 were the only pollutant measured by EPA’s air monitoring network above the Ambient Air Quality National Environment Protection Measure (AAQ NEPM) air quality standard. The 24-hour reporting standard for PM2.5 was not exceeded. The air quality standards for nitrogen dioxide, carbon monoxide, sulfur dioxide and ozone were met on all days in 2012 (where there was sufficient data to demonstrate compliance).
Overall at the permanent monitoring sites, five days were measured above the air quality standard for particles as PM10. The five days exceeding the PM10 standard in the Port Phillip Region were local dust (23 March, 4 October), planned burning (5 April) and urban emissions (19 April, 1 June). Urban sources are typically vehicle traffic or domestic wood heaters.
For the third time, the Port Phillip Region in 2012 (2010 and 2011 previously) met the AAQ NEPM goal of not exceeding the particles as PM10 air quality objective on five days at one monitoring site since AAQ NEPM reporting commenced in 2002.
Low visibility generally occurring for one to a few hours on a day was measured across Melbourne exceeding the standard at all sites, with the highest frequency of events measured at Mooroolbark (12 days). This was an improvement on 2011 (18 days). The goal for visibility was not met at all sites. This was mainly caused from small particle emissions such as PM2.5 from planned burning and urban emissions.
Unlike the general air quality in Melbourne, the local air quality in Brooklyn was regularly impacted by particles as PM10, due to dust emissions from the local industrial estate. Targeted short-term air monitoring in Brooklyn designed to assess local impacts measured levels of particles as PM10 above the air quality standard on 30 days during the year in Brooklyn. This was an increase on 2011 (13 days), due in part to strategies put in place to reduce PM10 dust emissions from the estate. PM10 at the short-term air monitoring station at Francis St, Yarraville exceeded the air quality standard on one day.
Monitoring for benzo(a)pyrene at a roadside site in Yarraville commenced in late May 2012 and ran for 12 months.
During 2012 air toxics monitoring was conducted and completed at Dandenong South (a residential area surrounding a prescribed landfill and numerous small to medium enterprises) and Tullamarine (a residential area surrounding a former prescribed landfill). The results show the levels of benzene, toluene, xylene and formaldehyde (monitored only at Tullamarine) measured were below the Monitoring Investigations Levels.
In Geelong there was one day when the levels of PM10 exceeded the air quality standard attributed to local windblown dust, and low visibility was measured on five days. The air standards for ozone, nitrogen dioxide, carbon monoxide and sulfur dioxide were all met.
In the Latrobe Valley, there were no days where the PM10 air quality standard was exceeded and low-visibility events were measured on 21 days at Traralgon and eight days at Morwell East. This is an improvement on 2010 (26 low-visibility days) but not as good as 2011 (13 days). Low-visibility days were caused mainly by the accumulation of smoke from planned burns and/or agricultural burning and urban emissions, such as smoke from wood fires in the colder months. Levels of ozone, nitrogen dioxide and sulfur dioxide were measured below the air standards on all days during the year.
There was no monitoring in other rural regions in 2012.