Proposed Limpopo West Mine Concept Study ... - SRK Consulting

SRK Consulting: 447493: Limpopo West Geochem Page 162.4 Hydrology and HydrogeologyThe proposed project area is located within the greater Limpopo River Catchment, specifically withinthe A41E quaternary catchment of the Limpopo River and covers an area of 1 940 km 2 . This area ischaracterised by low rainfall and is drained by the Limpopo River, which is classified as nonperennial.The Limpopo River is located approximately 11 km north of the farm Welgelegen and runsin a north easterly direction, forming the northern border of South Africa. The Matladas River isapproximately 39 km to the west of the Welgelegen farm and is known to be used for irrigation andagriculture purposes (SRK, 2011). Generally, the site has a very gentle gradient (1:25) and slopes ina north easterly direction towards the Limpopo River, and a maximum elevation of 905 mamsl andminimum elevation of 845 mamsl.The hydrocensus conducted by SRK indicated that groundwater flow mimics the topography, flowingin a north westerly direction towards the Limpopo River (SRK, 2011). The major aquifer systemsgenerally associated with the coal fields consist of the following:Weathered zone aquifer: the geology is generally associated with soils and weathered rocks,the thickness of the layers ranges from 15 m to 20 m and recharge is mainly through rainfallinfiltration.Fractured zone aquifer: this aquifer occurs below the weathered zone and is a preferentialwater pathway mainly associated with geological structures such as faults, fractures and fissureswithin the rocks. Faults under tensional stresses are likely to be more permeable and goodaquifers. There is evidence of groundwater compartmentalisation indicated by chlorideconcentration differences on Eezaamheid and Daarby faults (SRK, 2011).The groundwater qualities previously assessed indicate sodium and chloride enrichment, whichreflect the geology of the area. Generally, the chemical signature of the groundwater in this areaexceeds irrigation guidelines for moderately tolerant crops, yet acceptable for livestock watering.Stable isotope analysis indicated that recharge is mainly from rainfall with minor evaporation prior toinfiltration.2.5 Mine PlanThree phases of mining are proposed by Sasol to mine the coal reserves at PLWM as presented inError! Reference source not found.. The mining will commence with a small mine and it isnvisaged that it will progress into a mega mine.The geochemical assessment focused on waste rock from the pit and discard from the plant. Wasterock will be deposited outside the pit on a demarcated overburden stockpile. Discard will bedeposited as discard stockpiles.Table 2-1: Proposed Phases of Mining at Limpopo WestProposedPhasePhase 1Phase 2Size ofMineSmallMineMediumMineArea/FarmPropertyDepth ofMining (m)Run ofMineCapacity(Mtpa)TotalCapacity(Mtpa)Welgelegen 40 - 50 0.4 0.4WelgelegenandGroenfontein40 - 50 16 16.4Mine ResiduedepositOverburden,Interburden, topsoiland beneficiationplant discards.Overburden andinterburden dumps toa maximum height of20 m.Overburden,Interburden, topsoiland beneficiationplant discards.Overburden andNotesOnly upperEcca zones tobe minedincludingzones 10 and11.Only upperEcca zones tobe minedzones 10 and11.GOGP/LAKJ Report_April2013_19April2013 (1)_Final_Ludi_22052013 April 2013