Air emissions

Our mining, smelting and processing operations generate air emissions, which can pollute the atmosphere and affect nearby communities. We measure our emissions and are committed to controlling and reducing them. We focus our efforts on those emissions of most concern: sulphur dioxide and particulates (dust which can be contaminated with heavy metals).

As well as monitoring, we set ourselves targets to reduce emissions and to capture more sulphur dioxide. This approach has been working, with emissions of sulphur oxides from all our mines dropping over the last three years.

Sulphur dioxide

Sulphur dioxide (SO₂) is emitted during the smelting of metals. Apart from greenhouse gases, SO₂ is our most significant emission to air. SO₂ reduces air quality and contributes to acid rain. Our most significant source of SO₂ is Mount Isa Mines in Queensland, Australia, which currently produces about two thirds of our total SO₂ emissions.

We have targets to reduce SO₂ emissions and increase the proportion of emitted gas capture. Activities include:

• At Mount Isa, Australia, our Copper and Zinc businesses are assessing the feasibility of increasing the capture of SO₂ from their smelters to 95% by 2012 for the copper smelter and 98% by 2012 for the lead smelter
• At Sudbury, Canada, Xstrata Nickel aims to reduce SO₂ emissions to less than 25,000 tonnes per year by 2015, as well as cutting particulate emissions to less than 250 tonnes per year - a 40% reduction on 2006 levels
• Xstrata Zinc aims to maintain and improve capture rates at its operations: San Juan de Nieva (99.75%); Nordenham (99.8%); Hinojedo (99.7%); CEZ (98.5%); and Brunswick smelter (92%)
• Xstrata Copper has already achieved its goal to capture over 95% of SO₂ at Horne

Dust and heavy metals

Mining operations produce dust, which can sometimes contain heavy metal particulates. We have a number of ways to minimise dust emissions, including:

• particulate filtering and collection units within processing operations
• regular spraying of mine roads, stockpiles and mining areas with water
• using dust monitors to alert mine supervisors when dust levels increase

During 2010, Xstrata Coal responded to community concerns about dust emissions both at its South African operations and in the Hunter Valley in Australia. These are areas where ambient air quality is affected by a variety of local industrial activities and other mining companies in addition to our mining and processing facilities. Our response involved:

• engaging with other industry members, government and community representatives to better understand how to reduce or eliminate the potential public health risks
• providing financial support for improved air quality monitoring networks
• conducting benchmarking exercises to learn from the experience of others
• improving our own dust management processes