Presentation to the Portfolio Committee: Water& Environment Impact of Current Rainfall / Flooding on Acid Mine Drainage in Gauteng Presentation by Mr N Nepfumbada Acting Deputy Director-General: Policy & Regulation 26 - 27 January 2011

Leads to increased mine water levels and decant of AMD High rainfall / flooding leads to increased ingress of water into mine workings via: Surface streams Shallow groundwater systems Open pit mining Leads to increased mine water levels and decant of AMD 2

Status of Western Basin (West Rand) Dry season: zero AMD decant or relatively small volume (2 ML / day) + {12.5 ML / day partially-treated mine water} Wet season: AMD decant of 15.5 ML / day (Dec 2010) up to 30 ML / day (as at Jan 2011) + {12.5 ML / day partially-treated mine water} Impacts on Tweelopies Spruit flowing to the Crocodile River system. Recent fish kills not due to AMD. 3

Status of Central Basin (Central Jhb) Dry season: mine water rises by 0.3 m / day Wet season: mine water rises by 0.9 m / day Current rate of rise is 0.37 – 0.47 m / day Despite high rainfall, the rate of rise is less pronounced due to delayed ingress or greater void volume at 500 m below surface level (lateral spreading of water) 4

Status of Eastern Basin (East Rand) Recent rainfall has increased rate of mine water rise to 0.4 m / day (7 x increase) Pump station can flood within 16 days at this rate Grootvlei Mine has reported urgent measures underway to increase pumping capacity 5

Recommendations As per Expert Team report to the Inter-Ministerial Committee on Acid Mine Drainage, interventions include: Western Basin: reduce ingress by pit filling and canalising watercourses Central Basin: ingress reduction by canalising streams over mining areas + grouting (sealing) of mine paths Eastern Basin: immediately expand culvert in Blesbok Spruit to reduce water entering mine The above recommendations have been included in a Cabinet Memorandum which will be processed shortly 6

The End Thank you