Posted on: April 19, 2011 Posted by: Diane Swarts Comments: 0

Gauteng city region faces acid mine drainage (AMD) and water supply problems. A conference in Johannesburg in May 2011 outlines AMD risk and management options.

AMD flow has far reaching and long term effects, including poisoning of groundwater, surface water, food crops, and ecosystems, as is already occurring in the Mogale City (Krugersdorp) nature reserve.

AMD impact management is a long term exercise, crucial to low lying land use and property values. Several African and world cities and industrial regions face similar mining, industrial and pollution acid drainage problems, or high minerals ‘salts’ loads in groundwater plumes and surface streams.

Water scarcity in Gauteng’s gold reef cities, located on a major watershed named Witwatersrand Reef, lacking rivers, is exacerbated by pollution of surface water and nearby groundwater.

Reef cities have their water pumped from distant wells and from the distant and highly polluted Vaal River, bearing agriculture, mining, industrial, and sewage waste, some of which accelerate sedimentation in a series of dams.

AMD report to inform policy

A range of organisations and programs are already involved in AMD research and remediation, but the South African government has yet to finalise an AMD plan based on a specialist AMD report, drafted by a large team of specialist, led by the Council for Geoscience of SA, CGSSA (see details of the CGSSA report, and related reports on Sheafrica.com)

The conference unites experts on environmental aspects of mining and metals from the scientific community, state agencies, as well as mining and metals industries, to share knowledge, discuss industry practices, and sustainable management options for prediction, prevention, treatment, control and monitoring of AMD.

While the conference focuses on Gauteng, it could guide management of South Africa’s other major AMD problem, in the coal fields of Mpumalanga and KwaZulu-Natal provinces.

AMD sources

Acid mine drainage is a side effect of mining and quarrying operations the world over, due to;
* Rain water runoff from mine waste dumps
* Rain water leaching through mine waste dumps
* Mine waste water disposal into surface streams
* Mine shaft pumping and disposal to surface streams
* Sewage and waste water disposal in surface streams and artificial streams, entering mine voids by geological features and shafts
* Mine voids filling up with inflow and groundwater, until decanting into groundwater plumes, and into surface streams.

Rain water going to waste

Africa suffers from low conversion of rain water runoff to rivers. At continental level this conversion ratio is 20%, but in South Africa is only 10%, with the two most important river basins, Orange and Limpopo, at only 5.1% conversion rate.

The old paradigm of cheap coal based energy, externalised costs for strategic industries, and aggressive water mission that captured limited stream flow by building dams, and inter basin transfer by pumping.

Orange River system dams capture 2.71 times more water than the system actually gathers, due in part to pumping from other river systems, like the Lesotho highlands water project.

Water users should quantify water as a business resource risk, including water life cycle costing, and managing water flow, including recycling and dual stream reticulation, which water of different quality and price is delivered to users as custodians, instead of disposers.

South Africa is approaching a situation of ‘peak water’, with economic development restricted by supply constraints.

AMD conference objectives

AMD conference goals include;
* Find consensus on mine drainage quality prediction methods
* Use consensus processes to facilitate practical mine drainage solutions
* Consider the business case for improved AMD and ARD practices
* Identify knowledge gaps
* Identify needs for alternative approaches for acid drainage management.
* Identify cost effective AMD management options
* Identify improved water quality management options
* AMD neutralisation and metal removal in short term options
* Removal of ‘salt’ and pollution loads from river systems in the medium to long term
* Managing other AMD sources in the Witwatersrand basin
* Linking AMD hazards and risks, to mine planning, mine operations, and mine closure
* Managing AMD from mine waste materials
* Mine waste management
* Treatment options.

Learn from world AMD solutions

Dr Robert L Kleinmann of USA National Energy Technology Laboratory in the USA Department of Energy, vice president of the International Mine Water Association, studies worldwide AMD research and solutions including in USA, Canada, Britain, Australia, and Africa.

“Many AMD resources are readily available for free, or reasonably priced, including data on AMD prediction, prevention, remediation, and water treatment,” he says. Cities have to assess impacts correctly, using valid groundwater models.

AMD crosses state and private borders

Prof Anthony Turton, vice president of International Water Resource Association, professor at University of Free State Centre for Environmental Management, and director at Touchstone Resources, is an SA celebrity scientist who blew the whistle on poor state and local government management of their water protection responsibilities.

He studies AMD generation causes and impacts, legacy issues, uranium and radioactive contamination, pollution risk in the Witwatersrand gold fields, acid rock drainage, decanting of flooded mines, and dust pollution impacts on AMD.

Dr Turton is a ‘political scientist’ with 21 years of strategic level experience. He sees AMD as an issue of trans boundary water resource management, requiring negotiations on border river basins.

In city regions, AMD is a “state and private boundary issue of strategic significance in a water constrained mining economy.”

AMD liabilities and duties

Kym L Morton of KLM Consulting works in groundwater, hydro geology of kimberlite mines and specifically at Finsch mine in Northern Cape province. He studies AMD legal liabilities and duties for AMD sustainable management, responsibilities, liabilities, duties, obligations, principles, and enforcement.

AMD prevention and policy

Judith Taylor, branch co-ordinator at Earth Life Africa in Johannesburg, studies AMD prevention and control, effects on groundwater, methodological approaches, methods to cut off recharge, analysis methods, and AMD decision making processes.

AMD ecological impacts

Kim Kieser is CEO of Soul Foundation and Wet Africa, who launched the Jukskei River Restoration Business Chamber in 2011 as an investment vehicle and stakeholder legacy programme.

Kieser studies AMD impacts on communities and ecology, mining versus agriculture options in African experience, rural community impacts, mining remediation funding, regulation enforcement, and preventing new AMD disasters.

AMD specialists at conference

Dr Ingrid Dennis, director of the Institute for Groundwater Studies at the University of the Free State, conducts contract research on in mining and industrial water impacts.

Dr Petrus Daniel Vermeulen, lecturer and researcher at the Institute for Groundwater Studies at the University of Free State, teaches semester courses students in Aquifer Mechanics and related fieldwork, as well as Geophysics and Management. He also teaches environmental geology, and supervises honours, MSc and PhD students.

Mariette Liefferink is CEO of Federation for a Sustainable Environment and chairperson of Public Environmental Arbiters. She is also Associate at the Research Niche for Cultural Dynamics of Water at North West University Vaal campus, National Nuclear Regulator board member, DEA National Environmental Impact Assessment and Management Framework steering committee member.

Jason Beath of Australia is MD of Acid Solutions Group, which is treating sites thought to be untreatable.

AMD management conference booking

May 30 -June 01  Acid Mine Drainage (AMD) sustainable management conference, at SA Reserve Bank, Midrand.
May 30 Monday, themed on coal mining groundwater, recharge, sulphate generation, inter mine flow, passive treatment options, pollution extent, and water availability crisis.
May 31 Tuesday, themed on AMD corrective and responsible action options.
June 1 Wednesday, exhibition day.
Book on 021 671 0541, fax 021 671 3559, 086 628 0792, info@isiqaloubomi.co.za or www.isiqaloubomi.co.za

PHOTO; Groundwater sediment layers showing seasonal layers, with acid mine drainage (AMD) influx in the most recent layer on top.

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