An assessment against Victoria’s air quality objectives and goals is shown in the 2011 data tables (PDF 306 KB)
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 was 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 2011 (where there was sufficient data to demonstrate compliance).
Over all of the monitoring sites, 3 days were measured above the air quality standard for particles as PM10. The 3 days exceeding the PM10 standard in the Port Phillip Region were May 19 – Geelong South; May 20 – Geelong South and Mooroolbark; and June 1 – Alphington. All were attributed to urban sources, typically from vehicle traffic or domestic wood heaters.
For the second time, the Port Phillip Region in 2011 (2010 was the first) met the AAQ NEPM goal of not exceeding the particles as PM10 air quality objective on 5 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 (18 days). This was a significant improvement on 2010 (36 days). The goal for visibility was not met at all sites. This was mainly caused from small particle emissions such as PM2.5 from bushfires and/or 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 and Sunshine West designed to assess local impacts measured levels of particles as PM10 above the air quality standard on 13 days during the year in Brooklyn. This was a significant improvement on 2010 (36 days) due in part to strategies put in place to reduce PM10 dust emissions from the estate. One day was measured above the standard at Sunshine West.
In 2011 air toxics monitoring was conducted at residential sites in Tullamarine beside the old Tullamarine landfill. The majority of the air toxics were detected at low levels or not at all.
Tullamarine landfill community air monitoring program – Reports three and four
Also in 2011 air toxics monitoring was conducted in residential sites at residential sites surrounding the Dandenong South industrial precinct. The results show that for many substances the levels that were monitored were below detectable level. All substances at measurable levels in residential areas were less than the relevant air quality standards.
In Geelong there were two days where the levels of PM10 exceeded the air quality standard attributed to local windblown dust and low visibility was measured on seven 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 measured on 13 days. This was a significant improvement on 2010 (26 low visibility 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 2011.