This conference was very much about open discussion and active workshops with none of the typical scientific papers of the conferences I normally attend. For most subjects, this would be confusing and ineffective, but for mine management and safety, it worked. Discussions moved from mine operation and safety, to quality control and site management. At all stages the participants were either those working with these issues (the mine workers and managers) or the regulators and authorities [OSHA (Occupational Safety and Health Administration), MSHA (Mine Safety and Health Administration), National Mining Association, Department of Labour and so on]. This gave me a lot of time to actually ask more specific questions than usual and obtain far more detailed and relevant answers.
My current report for the CCC is on spontaneous combustion (sponcom) and related action plans. The Centre has produced several reports on sponcom in the past but these have concentrated on the chemistry of sponcom, on monitoring for prediction of incidents, and on quantification of gaseous emissions. This new report, at the request of our Australian and New Zealand Exco members, will concentrate on prevention and control of sponcom incidents at both surface and underground mines. This will include monitoring of emissions and temperature as predictors of potential outbursts and also treatment and control (management of piles and use of suppressants) as well as action plans for incidents (rapid suppression and explosion/fire control). This is something the CCC has never covered before and something which, outside Australia and New Zealand, is not covered well in the literature. Which is why this meeting in Texas was so helpful.
When I asked actual coal mine staff how they coped with sponcom at their mines, they smiled and replied “if it is on fire – we put it out.” While this may seem flippant, this was only the start of a more detailed conversation on how the crew learn to recognise early signs of potential sponcom situations and work towards prevention of further issues. These people learn on the job how to smell and see smoke before a carbon monoxide monitor has even registered an issue. They know how to act quickly to spread out the coal, to cover the area of concern or even to use a digger to literally lift out a burning pile of coal and take it elsewhere for treatment with water or suppressant.
For underground mines, the issue is far more complex – a combination of fixed monitors and personal monitors are used to indicate dangerous temperatures and gas mixes. But mines must work to ensure that the sponcom management plan evolves with the coal face – that monitors are always moved to the most appropriate location, that ventilation fans position and speed are optimised, that all equipment used is appropriate (eg intrinsically safe) and that sensors and equipment are located optimally to react immediately and effectively if any problem is detected.
The coal industry in New Zealand and Australia is still recovering from the tragic Pike River mine explosion of 2010 when 29 miners lost their lives. Australian technology for sponcom prediction and control is now state of the art and their expertise is used in South Africa, China, the USA and elsewhere. In fact, when I asked the Texas conference delegates about underground mine management plans, they all recommended that I contact BHP Billiton as they are regarded as having the best sponcom management plans in the USA. BHP Billiton is, of course, an Australian company.
This new sponcom report is due for completion in September 2015. I would be grateful for any information on best practice for sponcom control and for case studies at actual mines and stockpiles, especially for cases outside Australia and New Zealand. Please send any relevant information directly to [email protected]