Addressing air quality
Our principal atmospheric emissions are sulphur dioxide (SO2), total suspended particulates (tsp) which include dust, PM10 and PM2.5*, and GHGs. Disclosure of GHG emissions is discussed in detail in the section on Addressing climate change .
Air quality management is a significant feature of our overall environmental strategy and relates directly to several of our focus areas. Compliance with legislation and regulatory requirements is fundamental to maintaining our authorisation under air quality legislation to operate, which makes air quality management a critical component of the long-term success of our business. Through our engagement with GLC residents, we are aware that air quality is of significant concern to them.
We operate within our Atmospheric Emissions Licence (AEL) at the Smelter and BMR boiler, which was granted in January 2011 under the new National Environmental Management: Air Quality Act 39 of 2004 (NEMAQA). Our commitment to comply with our NEMAQA-aligned strategy has two main focus areas, emissions and ambient air quality management.
Measuring, reducing and managing our emissions
The primary contributors to our SO2 emissions are the Smelter and our BMR boiler.
In line with our AEL, our impact and emissions reduction strategy is aimed at meeting the 2015 and 2020 NEMAQ commitments and reducing, by 40%, the volume of ground level fugitive SO2 emissions by 2014 (from a 2010 baseline). Quarterly performance reports are submitted to the authorities and available for scrutiny by interested and affected parties.
In 2012, our average SO2 emissions from the Smelter were 8.5LA tonnes per day, which includes the coal from the BMR boiler. See the graph to the right for more detail. This is a decrease of 20% if compared to the 10.58 tonnes per day average in 2011. The significant improvement can be ascribed to increased performance in the availability and efficiency of the Sulphur Fixation Plant (SFP) and the Air Pollution Control Equipment during operating conditions.
The AEL conditions include that the total SO2 in tonnes per day should be below 17.9, the Air Pollution Control Equipment runs at 96% efficiency and 97% availability. In 2012 the Smelter operated well within these conditions. Two exceedances occurred in 2012 - in February 2012, when maintenance was required on the SFP from 20 February 2012 to 5 March 2012; and in August 2012, when the SFP plant was put on emergency bypass due to the unprotected strike and to ensure safety measures were applied.
The Company is also required to implement a SO2 reduction strategy and Fugitive Management Plan to reduce the SO2 emissions to specific targets set for 2015 and 2020. These include the installation of primary and secondary hoods on the Pierce Smith Converters and the installation of extraction fans to capture and stack fugitive emissions. This will inform options considered for implementation in the medium term. The Smelter is on track with its implementation of these measures and progress is reported in the legal quarterly reports to the North West Provincial Environmental Department. The implementation of the strategy is also aimed at meeting the sustainability target of reducing the volume of ground level fugitive SO2 emissions by 40% by 2014 (from a 2010 baseline).
Addressing ambient air quality
Lonmin undertakes continuous monitoring of our ambient air quality. The objectives of the monitoring programme include: to assess ambient SO2 concentrations, validate and inform atmospheric dispersion modelling, facilitate the measurement of progress against the fugitive management plan; tracking of progress and performance of air pollution control equipment, authority reporting, and informing the community and other stakeholders.
With regard to the averages for ambient SO2 for community sites, no exceedances of the national standard of 19 parts per billion were observed. No exceedance of the national standard has been observed since 2004 for community areas. Monthly averages continue to show a stabilising and reducing trend within both monitoring sites in close proximity to the Smelter and the adjacent community areas.
Total suspended particulates (TSP)
Tsp emissions emanate from the following sources at our Marikana operations: stacks and buildings, wind-blown dust from tailings facilities, drilling and blasting, material handling, crushing and screening, unpaved roads and paved roads. The chemical composition of this dust has been independently tested and does not present a health risk.
Lonmin undertakes dust fallout monitoring within our operational and community areas. Compliance to dust fallout within industrial areas is set at 1,200 mg/m²/day and in residential areas at 600 mg/m2/day. Over a period of 12 months, Lonmin has maintained 91% compliance to the industrial standard and 89% compliance with the residential standard.
The total cost of implementing environmental projects on tailings dams amounted R40 million (US$4.9 million) in 2012. At our operational tailings dams, dust suppression measures include the use of chemical suppression in the inner beach area on our larger tailings dams, pod or floppy irrigation systems, the grassing of the side slopes and alternate deposition of tailings to keep the beach area wet and the grassing of the side slopes of the tailings dams. All decommissioned tailings dams are vegetated on its side slopes and surface areas.
CASE STUDY: CaSO3 dam remediation
Lonmin recently completed the temporary remediation of two calcium sulphite (CaSO3) dams (residue stockpiles), which are situated west of the company’s BMR and Smelter complex near Marikana in the North West Province. READ CASE STUDY
As a member company of the ICMM, we recognise the potential risks associated with mercury emissions and support the ICMM’s position statement on mercury risk management. While we do not produce mercury, nor use it in any of our processes, we recognise that it may be present as a naturally-occurring trace element in the ore that we process. To determine the potential exposure risk, we are identifying and testing point source atmospheric emissions for mercury through sampling at the Smelter and at our refineries. We completed a high level mass balance for the period October 2011 to September 2012 where mercury emissions was estimated to be 0.094 tonnes emitted within this period. An occupational health risk assessment was also undertaken in support of the high level mass balance where mercury emissions were found to be negligible. Mercury is not of significance and our approaches are consistent with the ICMM position statement.
Other emissions, including those classified as ozone-depleting substances, persistent organic pollutants, volatile organic compounds and hazardous emissions are present at our operations, although to a significantly lesser extent. We are currently completing a thorough review of our emissions profile with a view to comprehensive disclosure by 2014.
The Hazemeter Campaign, implemented since 2010, was intended to inform both local and regional air quality management. This campaign indicated that both Lonmin sources and activities unrelated to the Company influence the ambient air quality of the Bojanala district, within which our Marikana operations are located. These activities include historical mining and other industrial activities in the region, as well as the burning of domestic fuel in the surrounding settlements.
Thus, our Air Quality Management Strategy considers these challenges holistically, in co-operation with the communities and local authorities, so that we can make a real and lasting difference to the air quality of the area. We are in the process of investigating the opportunity of mitigating activities that could enable us to collectively reach this objective.