Case Study: How the Cadia Valley Monitoring Program Expanded Its Air Quality Network

Excavators in a mining site

  • Topic: Cadia Valley Monitoring Program 
  • Industry: Air Quality, Air Quality Community, Air Quality Technology 
  • Author: Adrian Dybwad 
  • Website: 


With nearly 200 years of mining history, the Cadia Valley has been a significant source of air pollution. Extracting metals like iron ore, copper, and gold can release harmful air pollutants and airborne metals into the air we breathe. Because of this, communities near the Cadia Valley are in danger of developing air pollution-related illnesses.  

However, by establishing the Cadia Monitoring Program, the New South Wales Environment Protection Authority hopes to gain more insight into the mining pollution plaguing these communities. They’ve expanded their air quality network by using affordable air quality monitors, like PurpleAir, to gain hyper-local, real-time air quality data.  

In this air quality case study, we’re delving into Cadia Valley’s history of air pollution. We’re also covering how the government works to improve air quality through the Cadia Valley Monitoring Program. 

Cadia Valley’s History of Air Pollution 

Located in New South Wales, Australia, Cadia Valley is one of Australia’s largest gold mines. It was established in the 1800s, and it was originally a copper, gold, and iron ore mine. During this time, the miners and their families lived in the area to work, which meant that they were exposed to toxic mining pollution.   

Mining activities emit harmful levels of sulfur dioxide, nitrogen, and particulate matter. It can also release lead, mercury, cadmium, arsenic, and aluminum as dush, slag, and ash.   

However, particulate matter is the most dangerous of these pollutants. Fine particulate matter (PM2.5) can pass through your body’s defenses and create lasting damage to your health. The Environmental Protection Agency links the following health issues to particle pollution exposure 

  • Decreased lung function  
  • Increased respiratory symptoms  
  • Aggravated asthma  
  • Heart disorders and diseases, like irregular heartbeat  
  • Nonfatal heart attack  
  • Premature death in people with a history of heart or lung disease  

Moreover, mining pollution can continue contaminating the air, water, and land even years after the mining sites close. According to a study, 23 million people are affected by mining pollution from active and abandoned mines. 

Air Quality in Cadia Valley Today 

While the Australian government now has multiple air quality policies to limit the mining pollution from Cadia Valley, it still has its challenges.   

In 2020 and 2021, the New South Wales Environment Protection Authority (EPA) fined Cadia Holdings Pty Limited $15,000—the largest it can issue. This was because Cadia Holdings failed to conduct continuous air quality monitoring, which led to unhealthy levels of dust pollution.  

“Continual air monitoring of dust allows the operator to understand and reduce any potential negative impacts related to air quality,” explained Greg Sheehy, EPA’s Acting Executive Director of Regulatory Operations.  

Today, the Cadia mines continue to face controversy. Air quality data reveals that the mining pollution from the Newcrest Cadia Hill goldmine is over eleven times the regulatory limit for air pollution 

Additionally, the EPA noted that at least six properties have lead levels in their water above the health and environmental guidelines. However, it’s still conducting testing and research to understand the full extent of Cadia Valley’s mining and air pollution in nearby communities. 

How the Cadia Valley Monitoring Program is Helping Communities 

To ensure that Cadia Valley is complying with environmental regulations, the EPA established the Cadia Valley Monitoring Program 

The program seeks to expand its air quality network and experience the benefits of air quality monitoring, like spotting air pollution hot zones and gauging the effectiveness of air quality programs. As such, they used PurpleAir air quality monitors to expand their air quality networks and to complement their professional air quality monitoring stations.  

Even if affordable air quality monitors are not certified for policymaking, they provide invaluable insight into a community’s air quality. For example, an air quality study found that people are more likely to take action during a wildfire when they can access real-time air quality data from air quality monitors like PurpleAir.  

Additionally, PurpleAir’s air quality map allows everyone, even those without an air quality monitor, to gain vital information on their community’s air quality.   

Through the Cadia Monitoring Program, EPA hopes to:  

  • Measure and identify the air pollutants in Cadia Valley.  
  • Determine the source of air pollution and airborne metals affecting the communities. 
  • Engage the community in air quality monitoring and air pollution mitigation initiatives. 

The Cadia Valley Monitoring Program is still in its infancy, and we look forward to the data-driven insights it will bring to the communities surrounding it and the New South Wales government.   

About PurpleAir 

Since being founded in 2018, PurpleAir has dedicated itself to providing highly precise air quality monitors that track hyper-local air quality levels in real time. In doing this, PurpleAir is empowering community scientists and helping to facilitate social change through accessible air quality data for all. By working together, everyone is more informed and able to make changes in their local communities.