pdf [ 1.1MB ] - Anglo American

Spontaneous combustion ofcoal at Kleinkopje collierycan be controlled by the useof water jets to cool thearea being mined.Spontaneous combustionCoal and carbonaceous material will under certaincircumstances, spontaneously combust (sponcom)in the presence of oxygen. It is a loss of a valuableresource and poses a potential threat to healthand the environment. Sponcom generally occursin old underground workings that become exposedduring opencast mining activities, on spoil pilesand on discard dumps. Through proper compactionof discard, which minimises the voids availablefor oxygen, sponcom on discard dumps has beenmostly eliminated.Sponcom at Kleinkopje colliery, in oldunderground workings and on the spoil piles,has been an ongoing problem and a task teamwas established to look at ways of controllingthe problem. The team made significant progressduring 2005 by focusing attention on preventingthe ingress of oxygen to areas of heating, bycladding and capping cracks and openings withlayers of soil.Old and abandoned minesWith the purchase of Goldfields Coal in 1998,Anglo Coal acquired the closed Middelburg Steamand Station colliery. The colliery has been closedfor about 60 years, with underground workingsflooded in places, while other areas havecollapsed pillars and instances of spontaneouscombustion. The area is surrounded by informalsettlements and industrial sites.Anglo Coal's Greenside colliery has takenthe initiative to rehabilitate the area and is in theprocess of a feasibility study to assess the mosteconomical method of stabilising the old workingsand rehabilitating the area. The feasibility studywill scope and cost the rehabilitation programmefor submission to the Department of Mineralsand Energy and the Department of Water Affairs,in terms of section 43 of the Minerals andPetroleum Resources Development Act. In termsof the Act, it is necessary to submit a rehabilitationprogramme for approval in order to obtain aclosure certificate for a mine.It is likely that opencast mining methodsand the induced collapse of pillars will beused to stabilise the surface. Saleable coalwill be produced from the opencast miningoperation, with the profits being used to offsetthe costs of rehabilitation.32