Modern Quarrying January-February 2015

AT THE QUARRY FACE

expand PPC’s African footprint

Above: The back area at Zoutkloof which is filled with water is the final 180 m depth of mining. Here the limestone deposit sits at 55 o , and on the sidewall, one can see the phyllite which is screened out to the waste dump in order to enhance its quality. The area at the back of the pit is overburden from Vondeling, which has been backfilled into the pit. Centre: The current Zoutkloof pit is almost at the end of its life, and is currently running at about 170 m deep. The aim is to mine to a depth of 180 m with two benches still being mined. Left: Close up view of the topsoil and overburden, phyllite, granite and limestone.

He says the reserve quality is still high at this stage. Looking at the Vondeling pit which com- menced operation in 2007, the current depth is 50 m with planned mining until 2042. The final depth then will be 200 m. The aerial map shows a pink area, which was Phase One with a water canal running through a portion of the planned mine area. He says the new pit is roughly the same size as Zoutkloof and has the same quality limestone orebody. The map shows the concurrent rehabilitation taking place at Zoutkloof, and the overburden/ waste from the pit. “As we are opening up the new pit, we are closing the old one. We will actually be able to fill the whole pit and form a little bit of a hill. We are currently at -60 m below sea level, and will go down to -70 m.” The old waste overburden dump has been rehabilitated and the farmers renting the area have planted wheat fields and are utilising the land for agricultural purposes. There is no difference what- soever between the natural and the rehabilitated areas. Diergaardt has been with the PPC group for six years, having started off at PPC Riebeeck in the Western Cape, then moving to the Eastern Cape,

followed by Dwaalboom in Limpopo Province. He says he is very proud to be part of the tran- sition phase at De Hoek, “which is very exciting because we are closing one pit and opening up another. Shale is also sourced from the De Hoek operation, and Diergaardt says there are a lot of shale reserves. Showing MQ the two major shale deposits on the aerial map, he says when mining in Vondeling began; there was a lot of shale which was mined when the pit was opened up. “There is a huge stockpile in the pit area, and we are focusing on that at the moment. “What happened with the initial design which went downwards is that after drilling we realised that there was another limestone body sitting closer to the surface, which means less overburden stripping. This is why the river diversion plan came in. The deeper deposit is sitting at a 55° angle, and as you go eastwards it is getting deeper, so the moving of the canal is critical for us to be able to mine in that area,” he explains, adding that this will be carried out by the end of this year.

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MODERN QUARRYING

January - February 2015