Mine Closure Paper

Discussion Paper, September 2012

Environmental Earth SciencesEnvironmental Mine Management

WWW.ENVIRONMENTALEARTHSCIENCES.COM

Mine Closure and WasteResponsibilities and Liabilities

Discussion paper by Philip Mulvey, Alan Baker and Peter Scott

2 WWW.ENVIRONMENTALEARTHSCIENCES.COM

MINE CLOSURE AND WASTE - RESPONSIBILITIES AND LIABILITIES, SEPTEMBER 2012

Acid and metaliferous drainage from a rock wall in the in-filled pit of Mt Todd Gold Mine, NT. The mine closed in 2000 leaving the NT Government to fund around $10M deficit from the mining bond to manage the site. (Source Philip Mulvey)

CONTENTS

EXECUTIVE SUMMARY 2WHY HAS MINE CLOSURE BEEN SO DIFFICULT TO ACHIEVE? 3The Mining Legacy 3Tools for gaining a social license to operate 5Communication with the publicpoints to ponder 6TECHNICAL ISSUES OF MINE CLOSURE 7Key concepts and issues of mine closure 7Traditional mining waste cover designs 8MANAGING THE CLOSURE PROCESS 11Current closure practices 11Lessons from successful relinquishment of mine lease 12How to calibrate your CSM for closure: process monitoring 13Systematic management of mine waste 14A working example of systematic mine waste management 15Conclusion 15References 15ABOUT THE AUTHORS 16About Environmental Earth Sciences 16Contact 16

In a perfect world, mines would only close when their economic reserves and resources are exhausted and a mine closure plan is in place and progressively implemented, e.g. the coal seam is completely extracted, or the mineral orebody has been completely recovered, and no more coal or ore can be extracted economically. Mine closure is a process: a period of time when the operational stage of a mine is ceasing or has ceased, and the final decommissioning and final mine rehabilitation is being undertaken. Closure can be temporary in some cases, and/or may lead into a program of care and maintenance. The term mine closure encompasses a wide range of drivers, processes and outcomes. A century ago when mines ran out of ore, production stopped and mines were simply boarded up and abandoned. That was mine closure. Even today, that practice is sometimes still followed. However, most countries and most companies now recognize that mine closure is much more than stopping production and decommissioning the mine. They readily accept that mine closure also requires returning the land to a useful purpose (Sheldon and Strongman,2002).

Mine completion ultimately determines what is left behind as a benefit or legacy for future generations. If mine closure and completion are not undertaken in a planned and effective manner, a site may continue to be hazardous and a source of pollution for many years to come. The overall objective of mine completion is to prevent or minimise adverse long-term environmental, physical, social and economic impacts, and to create a stable landform suitable for some agreed subsequent land use. Effective mine closure is dependent on correct management of the mining waste through the life of the mine. This is best facilitated by understanding the potential mine waste before mining commences. Mine closure planning therefore commences before mining starts and continues through the mine life till the lease is handed back.

Mine closure planning is an essential component of any mining operation. It is a process that must be ongoing from the mines inception and throughout the entire life of the mine to ensure, as far as practicable, that the post-mining landscape is environmentally, socially and economically sustainable. Although mine closure planning has been practiced since the mid 1970s, voluntary forfeiture of mining leases and closure acceptance by regulators has been rare. To help understand why, this position paper provides an evaluation of a few successful closure cases and discusses the technical and commercial aspects required for successful closure.

This discussion paper provides a follow- up to a seminar series presented by Environmental Earth Sciences throughout 2011 at various locations around Australia. The seminars were held for scientists, engineers, planners and lawyers who work directly or indirectly in the mining industry, including mining companies, suppliers, consultants and regulators.

Environmental Earth Sciences

EXECUTIVE SUMMARY

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The numerous scars of open cut coal mines in the Upper Hunter Valley, NSW as visible to the public via Google Earth images. (Source: Google Earth)

closure. At the same time, because of this lack of communication, the farming community points to the failure to achieve closure as justification for not allowing exploration on their land.

Since anti-mining protestors started targeting funding groups such as banks and wholesale investment funds, the funding groups have become increasingly reluctant to fund projects that cannot demonstrate sustainability and good community relations. Therefore, future funding of projects will depend on effective environmental management in order to gain a social licence to operate. Similarly, gaining access to land for exploration will depend on the companys current and previous environmental performance in sustainable practices.It is apparent that a social licence to operate depends entirely on:1. current and previous performance;2. honest and clear communication with the public

and authorities regarding closure; and3. meeting stated commitments.

The Mining LegacyMany historic legacy sites exist throughout Australia and overseas where mines have disposed of mining waste inappropriately, and often have just walked away without any attempt at rehabilitation of the mine site and in some cases with the equipment left in place. Prominent owners of mining legacies, in Australia and across the world, with substantial acid metalliferous drainage liabilities are listed in the tables overleaf. The damage from these mines is visible to the public and is regularly reported in the media. As such, it is es-sential for the mining industry to demonstrate that it has improved in environmental management and learned from mistakes of the past if it is to establish a positive reputation with the public.


In the late 1990s triple-bottom-line reporting became popular and the concept of social licence to operate also gained prominence. The impacts of social licence to operate became increasingly apparent across the world, with public social conflicts slowing mining exploration, shutting down mine operations and indirectly preventing voluntary relinquishment of mine leases (mine closure) as governments refused to take the leases back. As Pierre Lassonde, President of Newmont Mining Corporation stated:

Social Licence is the acceptance and belief by society, and specifically our local communities, in the value creation of our activities, such as we are allowed to access and extract mineral resources... You dont get your social licence by going to a government ministry and making an application or simply paying a fee...It requires far more than money to truly become part of the communities in which you operate .

Pierre Lassonde, President of Newmont Mining Corporation, 2003.

Social conflict not only impacts the operators, but also affects their financiers who may withdraw from socially sensitive ventures for fear of reputational and/or financial damage.

An increasing demand for both coal and gas has fuelled the rapid expansion of the coal mining and coal seam gas industries. However, these industries are also experiencing increased conflict with local communities.

Across the Hunter Valley, NSW, the scars of open cut mining are visible to the public when flying over the Hunter in commercial airliners, and through viewing satellite Google Earth Images. Unfortunately, the successful cases of progressive closures in the Hunter Valley have not been adequately communicated to the public, and so there is a public fear that these mine sites will look as they currently do, even after mine

WHY HAS MINE CLOSURE BEEN SO DIFFICULT TO ACHIEVE?

Written by Philip Mulvey

Acid mine drainage from legacy mining waste at Brukunga SA.



GLOBAL MINING LEGACIES

Rio Tinto mine, Spain, initially mined in 3000 BC.

Iron Mountain, California, USA (Superfund) generates 20-40 tonnes of sulfuric acidity per day. This will cost over US$950 Million and take over 30 years for remediation.

Equity Silver in British Columbia, Canada, generates 20 tonnes of sulfuric acid per day.

Berkeley Pit in Montana, USA generates 30-50 tonnes of sulfuric acid per day.

Bingham Canyon in Utah, USA generates more than 20 tonnes of sulfuric acid per day.

Abandoned or orphaned mine sites cover more than 240,000 km of the Earths surface and can be a hazard to humans and the environment.

There are more than 50,000 polluting, abandoned mine sites in the US.

And more than 200,000 polluting abandoned mine sites worldwide.

AUSTRALIAN MINING LEGACIES

Yerranderie NSW is currently in a National Park and in the Sydney water supply catchment, this site comprises numerous abandoned mine workings, waste rock piles and tailings heaps that contain high metal concentrations, including As, Ag, Cu, Pb, Zn, Sb.

Ardlethan, NSW is an abandoned tin mine with sulfidic waste rock and tailings; serious acid and metalliferous drainage from tailings, waste rock, pit, stockpiles and the processing facility.

Hercules Mine, Tasmania is the highest mine site in Australia; mined Pb, Zn, Cu, Ag and Au; discovered in 1894 and mined periodically up until 1980s. It contains metal sulfides and discharges acid and sulfate drainage and metal leachate.

Mount Lyell Copper Mine, Tasmania was mined from the late 1800s to 1980s; acid and metalliferous discharge into both the King and Queen Rivers and Macquarie Harbour, continuing today at a discharge rate of 80 tonnes of sulfuric acid per day.

Brukunga Pyrite Mine, South Australia mined pyrite for the manufacture of superphosphate between 1950 and 1972. Has serious acid drainage generation such that it costs $1M annually to treat two tonnes of sulfuric acid per day.

Mount Morgan Copper Mine, Queensland was founded as a gold mine in 1882 and, as the Mount Morgan Mine, has produced gold, silver and copper. Since operations ceased in 1981, significant acid drainage and metal leaching into the local river system from waste rock, tailings and the mine pit has occurred. The mine generates 20 tonnes of sulfuric acid seepage daily.

Mount Todd, Northern Territory was originally a gold mine with cyanide and acid drainage generation, it was opened and closed several times, with limited rehabilitation. Eventually closed in the early 2000s due to bankruptcy. The cost to remediate far exceeded the bond.

Ballarat mines, Victoria where arsenic calcined tailings are scattered throughout residential areas.

Wittenoom, Western Australia is a blue asbestos mine where the local impact is asbestos tailings and mine waste discharged into the local creek. The regional impact is still being felt.

Other key legacy sites in Australia include Woodlawn, Savage River, Cosmo-Howley, Woodcutters, Rum Jungle, and many other major mines.

Acid mine drainage from a tailings dam at the Ardlethan Tin Mine, NSW. The mining company went into liquidation without undertaking any remediation, leaving a $1.9M clean up bill, mostly funded by taxpayers.

Mining Legacy - flooded pit void at Mt Morgan Gold-Copper Mine, QLD

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Tools for gaining a social license to operate

Maintaining complianceIn the last three decades there has been an increase in public awareness and involvement regarding environmental issues associated with mine development. As a result of this growing environmental awareness, miners are now expected to meet local laws, be compliant with environmental codes and address community outrage. There are three developing compliance regulations relating to sustainable practices and liability management will impact greatly on closure planning and costs.These are:

1. compliance with United Nations Principles of Responsible Investment (UNPRI);2. International Accounting Standard (IAS137)in Australia, the proposed AASB 137; and3. the application of the principle of polluter pays to mining.

United Nations Principles for Responsible Investment (UNPRI)The wholesale investment community of Australia, including superannuation management funds, have agreed to adopt UNPRI sustainability principles - a decision that applies to all new investments. In the future, companies complying with UNPRI principles are likely to be able to obtain investment funds at a lower cost due to having a lower beta valuerisk based pricing. That is, they will obtain cheaper rates on capital borrowing. Consequently, in the future it will no longer be an option for ventures comply with UNPRI or not, as not doing so will mean the cost of capital will render the venture non-competitive compared with those that do comply. During a mining boom this may not be of great concern but it will become so when the boom tapers off.

Currently, asset investors do not know how to apply UNPRI and asset owners do not know how to report to it. However they are learning, and the gap is closing as the ANZ and Gunns scenario indicates.

Accounting the costs of environmental liabilitiesProvision, Contingent Liabilities and Contingent Assets (AASB 137) is an Australian Equivalent International Reporting Standard (AASB 137), which is used to calculate financial liabilities associated with mining projects.

On 15 March 2010, a discussion paper (ED 191) entitled Measurement of liabilities in AASB 137 (Limited re-exposure of proposed amendment to AASB 137) was released by

Australian Accountancy Standards Board. This discussion paper focuses on the process of updating the Australian Equivalent International Reporting Standard (AASB 137) to be in line with International Standards IAS137 regarding contingent mining liabilities and how to account costs for plant decommissioning and dismantling where it has direct application to the mining industry. AASB 137 is based on the best estimate of the expenditure required to settle the present closure obligation at the reporting date. The standard update is proposed to ensure that bundled debt structures, which precipitated the Global Financial Crisis in late 2008, have full liability expressed in the current accounts. The manner of the proposed wording has resulted in environmental liabilities being required to be expressed in current accounts - that is, the amount the entity would rationally pay to settle the environmental obligation at the present day. However, the proposed accounting standard does not consider gains from the disposal of the asset.

The current accounting standards only consider closure costs when there is more than 50% probability of an event occurring that would lead to mine closure in that year (such as a drop in metal prices). Whereas the proposed Standard states that the estimate of closure costs has to be bought into current year if probability of closure in the next five years is greater than 10%. It is anticipated that this new accounting standard will come into force before 2015 and is awaiting the Australian Accounting Standard Board decision. However, the mining industry is lobbying to further postpone the Standard, and as yet, no other country has introduced it.

Lessons from industry polluter paysThe community expectation is that the polluter must pay for any environmental damage caused by their operation or activity. This precedent has already been set in the industry, whereby if the polluter sells the operation or property, and the buyer goes bankrupt or does not ameliorate the pollution/ contamination, it is the polluter who is held accountable.

This means that companies who transfer mines when reserves diminish may no longer be exempt from paying their contribution for closure. So with regard to historical contamination in industry, buyer beware is no longer the case. As such, in the mining

Mine protestors from a community in Boggabri, NSW. (Source: Rising Tide, http://www.risingtide.org.au/)

Mining legacy - abandoned mine workings with eroding mine wate at Yerranderie, NSW. (Source: Philip Mulvey)



industry, there is a need for a stronger focus on closure during the years when the mine is most profitable.

Redefining riskPublic involvement in environmental issues was first proposed by Risk Communicator, Professor Sandman in the mid 1980s. He realised that the traditional way of assessing risk was incomplete when considering environmental impacts.

Traditionally, the risk of a hazard occurring = consequence + likelihood of occurrence. However, Sandman noted that some projects were still being stopped or had failed to gain approval due to political and public pressure, even when the risk was low. Consequently he redefined risk by introducing a new term outrage:

risk = hazard + outrage

In this way, the risk of a project not proceeding or succeeding is calculated by assessing the hazard (the scenario of potential harm) and the likely occurrence of community outrage.

Not meeting responsibilities = OutrageOutrage occurs when a mining company is perceived to have not, or actually has not, met the responsibilities of operating a modern mine. An absence of outrage means responsibilities are understood, communicated and met. Operators must be aware that in this age, the failure to comply with either liabilities or environmental responsibilities can be communicated globally and very quickly. Specifically, this may involve how closure is approached throughout the life of the mine and how it is communicated to the community, thereby creating the social license to operate and to close.

Successful closure is important because if they are not successful and perceived to be successful by the public, further conflicts are likely to occur when operators:

seek new exploration licenses ; and attempt to source capital funding for new ventures

Governments are cautious to accept leases back, because they are afraid of inducting more members to the List of Minings Legacies.

Planning for mine closure using over 45 years of experience 1973 - Mine rehabilitation was first required by law in New

South Wales in 1973, and the other states soon followed. 1976 - The first Australian conference on mine closure, or

as it was known then, mine rehabilitation,. It was called Rehabilitations of mined lands in WA, and was held in Perth in October, 1976 at the WA Institute of Technology (now Curtin University of Technology).

1978 - The first journal publication on mine rehabilitation in Australia was a special issue of the Journal of the Soil Conservation Service of NSW, which included a paper on Mt Whaleback, WA, regarding the first mine site rehabilitation trials, May 1975 to December 1978 by J. Riches and H. Jones, barely seven years after the mine commenced operations.

The Industry has been carrying out mine rehabilitation and preparing for mine closures for at least 45 years. One would expect that there should be a very good understanding of the mine rehabilitation processes. So why arent authorities signing off on mine closure to enable lease relinquishment?

Are technical issues the problem, or are processes of closure currently not followed? New, unsustainable mining legacies should not be created, but they are. Why is this so? These questions are explored further in the following sections on mine waste and mine waste management and the commercial aspects of mine closure.

Communication with the publicpoints to ponderIf environmental liabilities can be predicted and mitigated so that mines can readily achieve closure, why is voluntary lease forfeiture still not being accepted by government? In light of a history of obvi-ous closure failure, the real question is how do we demonstrate that closure can be successfully achieved? Are successes being communicated effectively? Mine closure is clearly more than just a technical problem.

The photograph to the right is copied from a brochure placed in accommodation in the Hunter Valley by anti-coal seam gas protesters. It is a photo of an operating coal mine, not a closed mine or an abandoned mine, though key features in this photo may have been unchanged for many years. The brochure used the photo as an example of the legacy of mining, arguably to imply that this photo represented mine closure. The reason why the public may see this picture as the mining companys closure strategy is either a poorly closed mine or a poorly communicated closure process.

When the public takes a tour of a major mine, what are they shown? Most tours will include a huge pit, the load-out area and an impressive processing facility. A large board at the

mine office usually displays the number of operational days that have been accident and injury-free, which is evidence that the Mine takes health and safety seriously. However, there is no mention of progressive rehabilitation displayed on a billboard at the entry to the mine site.

Further, with most tours, there is no attempt to show and discuss the environmental program, the progressive rehabilitation, the nurseries, the rehabilitation trials, the management of mine water and dust, and the environmental monitoring that is undertaken routinely throughout the mine life. The story of the mine closure plan is an important story that needs to be told.

Photograph of an open cut mine in the Hunter Valley taken from a pamphlet by Greening Lovedale Hunter Valley, July 2010 (Photo Source: Cate Faehrmann http://www.catefaehrmann.org/)

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Key concepts and issues of mine closure

Closure is the permanent cessation of operations after completion of the decommissioning process and tenement relinquishment. A century ago, when mines ran out of ore, production stopped and the mines were simply boarded up and abandoned (World Bank Group, 2002). That action was considered to be mine closure. Even today, that practice is sometimes still followed, however, most countries and companies now recognise that mine closure means much more than simply ceasing production and decommissioning the mine and equipment; mine closure also requires returning the land to a useful purpose.Mine completion ultimately determines what is left behind as a benefit or legacy for future generations. If mine closure and completion are not undertaken in a planned and effective manner, a site may continue to be hazardous and a source of pollution for many years. In Spain and England, the Roman mines still remain a source of pollutants into river catchments between 1700 and 2000 years after mining ceased. The overall objective of mine completion is to prevent or minimise adverse long-term environmental, physical, social and economic impacts, and to create a stable landform suitable for some agreed subsequent land use. Decommissioning is not just an end process it may begin very early in the mine life, peak after cessation of mine production and end only with tenement relinquishment. It involves the removal of unwanted infrastructure, making excavations and waste repositories safe and stable, surface rehabilitation and minimising any adverse environmental impacts remaining after mineral production ceases. It includes the maintenance that may be needed until relinquishment of the tenement.Mine closure planning is an essential management tool for the industry to achieve successful closure. It is necessary to identify early the risks associated with the mine closure so that early and progressive mitigation and rehabilitation can be planned. Any uncertainty associated with projecting the effectiveness of mitigation should be reduced by replacing assumptions with actual measurement, which will also provide increasingly more accurate cost of closure for inclusion in company accounts.

The closure plan should also ensure that the accountability path is clear and that there are adequate resources available for the implementation of the plan, as well as for a monitoring and review program to calibrate the models of prediction. Such modelling and other data are used to establish a set of indicators to demonstrate the successful completion of the closure process, rather than assumptions.

During the planning stage for mine closure, all relevant stakeholders should have their interests considered to ensure successful long-term management of the final plan.

Though mine closure planning is ongoing, the technical outcome is an agreed Rehabilitation plan, which considers: characteristics of the mine land and surrounding

environment; the need to stabilise the mine land; the desirability to return agricultural land to a state that is as

close as is reasonably possible to its state before the mining licence was granted; and

any potential long term degradation of the environment.

Written by Peter Scott & Alan BakerTECHNICAL ISSUES OF MINE CLOSURE

Peter Scott inspecting a waste rock dump at Brukunga, SA. (Source: Philip Mulvey)

The planning of closure rehabilitation works should be undertaken in consultation with the land owner, land custodian and the local community. If it is to meet mine closure objectives, mine site rehabilitation must be carried out progressively throughout the mine life, and the way it is undertaken will have a substantial impact on the length of monitoring time required by the authorities before the lease is allowed to be relinquished.

Mining waste may include: mine process tailings; waste rock; heap leach material; mine water treatment sludges; or low-grade ore stockpiled on site whilst waiting for changes in metal prices or metallurgical improvements. The most common issues faced when managing mining waste include the wastes erodibility, its chemical reactivity, redirection and containment of surface waters and runoff, difficult rehabilitation, and keeping out weeds and vermin. These issues are discussed below.

Erodability of mining waste can be due to either mechanical properties of the waste material, for example, the physical transport of fines, or chemical dispersion of fines such as with clays. Chemical dispersion is more significant in materials with high clay content than in materials with less than 10% clay. The degree of dispersion that occurs will also be affected by salinity, which tends to suppress dispersion. Sodicity is also of concern because sodic materials are more prone to clay dispersion when wet. Sodic materials are generally materials with more than 5% of soil cation exchange capacity (CEC) dominated by sodium. Sodic mining waste can have extremely low permeability, poor drainage, are hard-setting when dry, and have considerable potential for the development of tunnel erosion. This problem is well-known and proven techniques have evolved to mitigate adverse impacts from this type of waste if it is identified early in the mining process.

Reactive waste acid metalliferous drainage is caused by sulfides (such as iron sulfides e.g. pyrite), which are common and widespread across the Earths crust. When sulfidic waste materials are exposed to air and water, sulfuric acid is produced.

This sufuric acid is then able to dissolve other minerals in the waste material to release potentially harmful soluble metals. These reactions are summarised in the following equations:

pyrite + water + air (oxygen) = sulfuric acid + iron in waterways and groundwater

sulfuric acid + soil + rock = elevated metal release into waterways and groundwater



Metals that often leach from mine waste material include: iron, aluminium, manganese, copper, lead, zinc, cadmium, arsenic, antimony, cobalt, chromium, nickel, mercury and molybdenum. Aluminium is the most toxic of these metals to aquatic organisms and plants, and is amongst the most common of the metals released as a result of acid drainage. While acid drainage most often occurs in areas where mining waste is stored such as waste rock dumps, stockpiles and leach piles, and tailings storage facilities, it may also occur in mine voids (both open cut and underground mines), wall rocks, and from high walls. The environmental impacts of acid drainage from historic poor practices can be readily seen by the public in aircraft or access to these abandoned mines, and include impacts to water supplies and resources such as those used for drinking, irrigation, livestock, fishing, recreation, tourism, aquatic ecosystems and loss of habitat.

Community outrage is often a result of these environmental impacts or the perception that they may occur. Economic and business impacts can also be extreme, and the costs are usually borne by the community or government. This can lead to accumulating liabilities for governments, for example superfund sites, and governments are decreasingly willing to accept the liabilities. As such, liabilities remain with the mining companies in the form of prevention of lease relinquishment, expensive remediation and rehabilitation processes and potential compensation payouts in the event of environmental and social damage, all of which will negatively impact on the mining companys reputation and future project approval prospects, as well as creating a negative perception of the mining industry as a whole.

In Australia, there are more than 100 mining companies and government organisations committed to acid metalliferous drainage treatment in perpetuity, although many sites have been returned to the community to fund. The Australian examples listed in the List of Minings Legacies on Page 4 are all orphaned sites, that is, sites in which the profits have been privatised and the liabilities socialised, so the public picks up the bill (through tax) for the environmental damage caused.

Surface water issues regarding mining waste primarily relate to limiting the erosion caused by water run-on, containment of contaminated runoff water, and limiting the flow velocity and flow volume of water over the site. Any reshaping of stockpile side slopes crushes and buries boulders, which causes decreasing erosion resistance and leads to an increase in slope length

and catchment size. This increases the runoff coefficiency by smoothing the surface which, in turn, increases erodability and increases the amount of sedimentation in streams leaving the site.

Mine-influencedwateris water that has been chemically affected by mine waste rock, mine walls, ore and tailings, mining and mineral processing. Chemical effects on water may result from exposure of mining waste to oxidation (see reactive waste above), release of process chemicals, and the introduction of nutrients such as nitrates from explosives used in mining. Mine-influenced water can be classified as: acidic; acidic metal rich; alkaline; alkaline with cyanide; neutral with reduced iron; neutral but metal rich (for example As, Se, Cu, Ni, Zn); neutral but sulfate dominated; highly turbid (usually due to a high sodium adsorption ratio); saline water; and nutrient-rich neutral water.

Each classification requires a different approach to prediction, monitoring, and control. Whilst these approaches are not discussed in this paper, a paper on how to monitor mine waters has previously been published by the authors (Mulvey, 1998).

Traditional mining waste cover designsMitigation of the above issues associated with mine waste can be achieved through appropriate, well-informed landform design, encapsulation and final cover design. It is a requirement that cover landforms are constructed to minimise environmental impact in both the short and long term. The landforms must also fit appropriately within the topography and use of the surrounding landscape. The main objective of waste cover design is to limit the exposure of erodible and reactive waste to air and water.

Cover design and construction must be undertaken in a manner that ensures the cover and final landform will perform and evolve predictably. Reactive material such as sulfidic waste rock or tailings and/or metal-leaching materials , will require isolation from rainfall infiltration. This is most commonly achieved in drier climates like Australia through encapsulation using benign waste material and a low-infiltration cover. In the case of waste rock dumps, placement of reactive waste beneath slopes should not be undertaken as rainfall infiltration cannot be prevented from

Iron sulfate salts forming on the surface of exposed tailings in the presence of water and oxygen. (Source: Philip Mulvey)

Philip Mulvey inspecting a seepage point at the toe of a waste rock dump, NT. (Source: Philip Mulvey)

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reaching the reactive waste in this position. Reactive waste should only be placed under horizontal surfaces.

Mine waste requires an appropriately-designed cover, the design of which must consider a range of factors, including: climate (wet, seasonal or dry); the nature of the mining waste; physical properties of the waste dump (degree of

segregation, particle size distribution, plasticity, moisture content and density);

geochemical behaviour (salinity, acid forming potential, metal leaching, potential for dusting and presence of radioactive materials);

mode of mine waste storage; construction; physical and geochemical nature of the cover materials;

and the post-mining beneficial land uses.

A cover usually consists of: A growth medium that has high water storage capacity and

sufficient depth for plant roots (>0.5m) to ensure a healthy growth of plants during the long term seasonal variation expected.

An outer capillary break and drainage layer to limit root penetration into the sea below. The capillary break must have a low air-entry value > thickness and water storage capacity;

A seal with a low hydraulic conductivity (< 10-8 m/s) and high air-entry value. The seal is to remain saturated;

An inner capillary break is required if mine wastes are saline and/or potentially acid forming; and

Waste from the mining process, such as waste rock or tailings.

Minimising impacts and liabilities using sustainable green cover systems The problem with the above cover design is a lack of compat-ibility with an uncontrolled growing medium. Invasion by plants post closure will occur, and with time tree roots and shrinkage cracks may develop causing the integrity of the cover to be potentially compromised. If this was to occur, the oxidation of the entombed sulfidic waste could cause the release of acid and metals to the environment. An alternate method is to design the covers to leak at the rate at which neutralisation mechanisms can keep up with the acid released. This can be

achieved by also including phytostabilisation in the cover design by using plants more effectively to remove excess water in growth medium layers coupled with the installation of a drainage layer using plants and slowly oxidise the waste without causing long term damage to the cover.

When considering waste entombment, the following questions should firstly be considered: Can we make it work forever? What is the life expectancy of the cover materials such

as clay, synthetic liners, growth medium, capillary break, drainage layer?

What are the operating and maintenance requirements? What is the final land use and what is its impact on the

performance of the cover? Is it viable to entomb waste given the answers to all of the

above?

A significant volume of research has been undertaken regarding cover systems, but there are still uncertainties about the effectiveness of cover system seals. These include concerns about clay and its longevity due to reported failures especially in arid areas, and concerns about composite membrane costs and the failure of membranes.

There is an increasing body of research on phytoremediation, phytocovers and phytostabilisation for waste rock dumps, tailings storage facilities, heap leach piles and mine water treatment sludges but there still remains a lack of long-term monitoring data on the effectiveness of engineered covers. Work undertaken by the USEPA has found that, no matter how thick, engineered covers have the potential to fail due to variability in climate and impacts by vegetation.

Understanding and managing water is the most crucial issue in the rehabilitation of mining waste. This includes too little water in arid/semi-arid zones, too much water in the tropics, and seasonal variability, distribution and intensity. Other issues include managing impacts of: run-off, percolation and run-out seepage rate and leachate quality, variable soil moisture water storage, and seasonal variability in evapotranspiration. Two solutions are currently being investigated and utilised to address these problems: 1) an evapotranspiration cover, and 2) a phytostabilisation cover, both of which are discussed below.

An evapotranspiration (ET) cover, or water-balance cover, comprises soil and plant system that maximizes water storage and evaporation/transpiration process. This cover is primarily a form of hydraulic control and achieves risk reduction by relying

Schematic cross-section showing encapsulation of mineralised waste (PAF) (Source: Williams, Scott and Gerrard, 2012) 07




The early development of a phytocover at a landfill site in Victoria where the cover material was dolomitic quarry waste. Locally-sourced eucalypts, native shrubs and grasses have been established directly into the cover. (Photo: Alan Baker)

on plant transpiration to control seepage/leachate. With an evapotranspiration cover, any water infiltration is stored as soil moisture in the cover to be transpired and lost to the atmosphere. However, potential problems with evapotranspiration cover systems arise when their design does not take into account soil moisture availability and depth, and when they fail to specify the right vegetation for the conditions to ensure diversity of root depths. During the establishment phase, it is important that there is good control of weeds and an abundance of early colonising plants. Many covers fail because of cracking, which develops during variable weather patterns or variable swell response to trees. Cracks, known as macropores, allow fast ingress of water and air, which allow for reactive processes such as acid production to take place. The design needs to either have a built in capacity to negate the impact of macropores by being thick and multilayered, or be designed to ensure that macroporosity does not develop, which is difficult in all climate zones except temperate.

To create an effective evapotranspiration cover for mining waste, the cover must: require minimum maintenance; be self-sustaining; and have a final vegetative cover that adequately controls

interception of run-off and leachate, is self mulching or, at the very least, has been designed to mitigate macroporosity and stabilises and protects the cover from uncontrolled erosion.

An Alternative Cover Assessment Program (ACAP), utilising evapotranspiration (ET) covers was introduced in the United States in the early 1990s for landfills. Its equivalent in Australia was the Australian Alternative Assessment Program (A-ACAP). Both have spin-off applications for tailings facilities and mine waste dumps. The three main aims of A-ACAP were: to extend the knowledge gained from the original USEPA-

based ACAP initiative; to develop national design guidelines for phytocovers; and, to expand the use of phytotechniques throughout Australia.

The major outcomes of the program were the demonstrations of cover systems incorporating sustainable vegetative phytocovers and no clay barriers appropriate for all the major climatic zones of Australia. Native species of grasses, shrubs and trees formed the basis of the initial plantings to generate working ET covers to effectively control rainfall percolation and subsequent leachate issues. Information from this work is applicable to the minerals industry in designing sustainable phytocovers. Information on the program is available from the following sources: USEPA (2010) Evapotranspiration landfill cover systems

Fact Sheet, July 2010 WMAA (October 2011) Guidelines for the assessment

design, construction and maintenance of phytocovers as final covers for landfills. Ref. No. 20100260RA3F.

Though these systems have their applications, research has been limited to two decades of trials. During this time it has been shown that macroporosity develops and considerable maintenance is required if vegetative covers are the sole method of eliminating moisture. This is applicable when management can occur, but outside 30 to 50 years it is difficult to set up a system that ensures cover maintenance. As evapotranspiration covers require ongoing maintenance, this type of cover system may not be suitable for many mine sites as a walk-away closure strategy.

Phytostabilisation covering utilises different process to evapotranspiration covers. Phytostabilisation covering involves direct planting into mining waste, with minimal surface amendment/amelioration. This type of cover is suitable for toxic materials if appropriate tolerant excluder plants are available to prevent food chain transfers. Excluder plants (such as the majority of grasses and eucalypts) restrict the transport of metals and metalloids from their roots to above-ground parts. Many such plants are early colonists of wastes and commence successional vegetation establishment and diversification as well as kick-starting the ecological processes necessary for soil formation. Once established, these systems should require minimal management as weeds are less of a problem on toxic substrates.

Phytostabilisation represents an ecological approach to sustainable mine closure. This approach emphasises the importance of establishing appropriate biological processes which are part of ecosystem functioning, including: nitrogen fixation and carbon sequestration; decomposition and microbial activity; nutrient cycling and retention; mycorrhizal systems; important biotic interactions, for example pollination; successional processes and biodiversity stability; and minimisation of risk of contaminant transport into potential

food chains.

A comprehensive program, supported by the Australian Government, Department of Resources, Energy and Tourism, known as the Leading Practice Sustainable Development Program for the Mining Industry has developed a series of handbooks including the following, which have application to mine waste covers: Mine Rehabilitation (2006); Mine Closure and Completion (2006); and Biodiversity Management (2007).

The handbooks address some of the issues associated with cover design and in particular, phytostabilisation and evapotranspiration covers.

Appropriate design of a cover system is essential to achieve long-term mine waste closure that is low maintenance and low impact. However, the notion of no impact beyond the mine waste emplacement is often not realistic. Rather, mine managers should aim for natural attenuation or an impact zone of minimal size, in which the surrounding environment attenuates discharges to background or to no adverse impact.

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Current closure practices

Most mine closure planning occurs with the initial mine plan, before operational data is available. At this stage, closure planning is founded on baseline surveys and predictions as to what will happen during mining. These predictions are known as a conceptual site model (CSM). A CSM should include designed/engineered features of the mine, which act to mitigate environmental impacts. Any foreseeable or likely impacts from the mine operation are usually included as conditions of the mine lease, including environmental and engineering monitoring conditions. For most mines, adequate investment in the closure plan does not usually occur again until the mine plan changes or the mine is approaching the end of its production life. Consequently, although it is critical to undertake mine closure planning progressively throughout the entire life of the mine, confirmation and application of the closure plan is usually left until cessation of mining is near.

Recently, the authors of this paper undertook a review of mines around Australia and found that although many mines had closed, very few had successfully forfeited their leases. If quarries, alluvial mining and other surface deposit mines, such as bauxite, and underground mines with no surface processing are removed from the list of mines who have successfully voluntarily forfeited their leases, the list becomes very short. Government regulators were also interviewed as part of the authors review. Following these interviews, the authors noted a distinct difference between the regulators expectations for mine closure at mine commencement, and at the end of mine production, when expectation is replaced with cynicism from the regulator.

Example 1 below shows this relationship diagrammatically to represent the confidence of regulators over the life of a mine, and the mines closure costs resulting from poor closure planning over the same period.

MANAGING THE CLOSURE PROCESSWritten by Philip Mulvey

From Example 1, we can see that initially there is high confidence from regulators and the community that the design for closure will be effective, that costs are realistic and can be managed. However, as mining proceeds, and limited or no rehabilitation works are undertaken, and/or insufficient communication with regulators and the community occurs, confidence in the mining companys ability to manage the site for mine closure diminishes.

At this point, the miner only collects the environmental data required by their license and no more even when it becomes apparent that the monitoring is insufficient to provide all the information needed for closure. When production ceases, costs start to rise rapidly as it becomes apparent that the closure plan is inadequate and ineffective, so corrective earthworks and rehabilitation are required. At this point, the expectation and confidence shown by the regulator and community reaches its lowest point, while costs for rehabilitation and closure continue to rise and exceed the original budget. The regulator and the community have lost faith in the ability of the mining company to rehabilitate the site and return it to a suitable land-use whilst minimising environmental impacts. As a consequence, the regulator is likely to impose an extended compliance monitoring program for the site, and insist that the mining lease be held in perpetuity.

This lack of confidence in the miners ability to predict environmental impacts of mine closure is the primary factor stopping the successful forfeiture of mine leases after the cessation of mining. Communities and regulators no longer want to privatise profits and socialise the liabilities.

It is apparent that the two main factors leading to the loss of confidence are: 1. a lack of acceptance of responsibility for mine waste, which is

the primary cause of environmental damage; and 2. a failure of the mine to calibrate the conceptual model used to

design the mine closure plan.

Confidence

Cynicism Cumulative cost ($)

Design Operations Production ceases

Closure Monitoring

Expected maximum closure cost

(planning stage)

TIME

EXAMPLE 1: CURRENT APPROACH


Schematic diagram of community and regulator confidence (red) and costs (green) over the mine life.


Therefore, the reason why there are not more success stories is not due to the mines lack of technical capability to do the work, but the current lack appropriate progressive action towards closure.

Lessons from successful relinquishment of mine leaseWhere are the success stories, and what can we learn from them? In their 30 years of experience, the authors are only aware of one mine in Australia that has been successfully closed and the lease handed back The Mary Kathleen Uranium Mine in north-western Queensland.

So what was it that worked at Mary Kathleen Mine? One of the authors of this paper was involved in the closure design and supervision of the Mine in the late 1980s, and looking back 30 years, it is clear now that certain circumstances and conditions resulted in a process that was, in retrospect, unique.

Mary Kathleen was a uranium mine which commenced operation in the early 1950s, operated until the mid-1960s and was then placed under care and maintenance for a decade. It was subsequently reopened in 1976 with a known but limited life. The groundbreaking Fox Commission Report into Uranium Mining released 1978 and 1979 for the first time in Australia, highlighted the environmental impacts of uranium mining. The findings of this report were immediately applied to the management of Mark Kathleen Mine to actively pursue the process of closure. The Mine began the active integration of closure into the mine plan six years before cessation of mining and processing. In addition, a substantial monetary provision was made for investigating and undertaking the closure process.

At the time, very little research had been undertaken to understand the behaviour of radionuclides in the environment, and studies into tailings behaviour and seepage were in their infancy. This meant that assumptions were not available for a site conceptual model, and so

real site-specific data had to be generated for all the technical aspects of closure. Therefore, a detailed understanding of the biogeochemistry, water in the landscape and geomorphological setting had to be developed prior to closure. Current data was collected and the long term behaviour of the mine was considered. The result for the conceptual site model for closure was that actual data was maximised, and assumptions were minimised.

Uranium is a radioactive ore and the greatest amount of radioactivity from uranium mines generally reports to the tailings dams. Consequently, at Mary Kathleen, leachate experiments were undertaken using columns of tailings to simulate long-term leachate

chemical characteristics. Because tailings leachate is dependent on pore-water volumes, rainfall intensity and rainfall duration, this simulation created projected data for 100 000 years of acidic weathering for input into the site conceptual model, rather than using assumptions derived from chemical equilibrium.

As tailings geochemistry was a relatively new science at the time, the emergence of somewhat contradictory research data from leaching and weathering trials on alkaline uranium tailings dams in Canada (Elliott Lake Mine) meant that a great deal of effort was put into understanding the weathering behaviour of tailings, waste rock dumps and pits at the Mary Kathleen Mine.

Whenever a conceptual site model is created or a computer model set up, real data is needed to calibrate the model. In the case of Mary Kathleen Mine, the models for pit inflow, tailings seepage and weathering behaviour benefited from having what was essentially a 10-year calibration during the mines closure in the late 1960s to early 1970s. Before the mining operations


Rocky mulch cover riprap placement on the Mary Kathleen tailings dam (Photo: Philip Mulvey,1985)

Investigation of tailings at the Mary Kathleen Uranium Mine tailings dam. (Photo: Philip Mulvey, 1980)

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recommenced in the mid 1970s, water samples from the pit and tailings seepage were collected and analysed, resulting in the models having a 10-year calibration with real weathering data.

In the 1980s, computer modelling was very new, and although the Apple II was released in Australia in 1982, computer modelling was still expensive and did not allow for numerous iterations on parameters for sensitive analysis. This meant that it was cheaper to spend money collecting real data than running numerous computer models., whereas today it is cheaper and easier to undertake computer modelling than to collect real data.

It is important to note that the Mary Kathleen Mine was handed back to the regulatory authorities in 1986. These days, it would be handed back to the public and closure requirements are likely to be different. Another point to note is that the Mine was closed for economic reasons and then

reopened with the specific objective of closing it effectively, so great efforts were made to calibrate the closure design model using real data. Also, being a uranium mine, the expectation was that it would close and never be re-opened again. With many mines today this is not the case, and in the last several years many abandoned mines have been reopened as the ore becomes economic to mine again.

In conclusion, the reason why the Mary Kathleen Uranium Mine was successful in achieving closure was due to the development of a conceptual model using real data to predict the long term geological behaviour of the mine waste, and confirming the model projections with real-time calibration throughout the life of the mine.

Consistent integration of the closure plan into mine operations was essential. Final landform of waste rock dumps and tailings was undertaken during mine operations. In this case, closure was not considered a separate activity but part of the responsibilities of the Mine Manager. During the last six months the milling was altered to suit the desired physical characteristics desirable of a self sealing tailings dam to aid long term closure - an example of how closure planning was incorporated into the final years of the mines operation.

How to calibrate your conceptual site model for closure: Process Monitoring There are two types of environmental monitoring in the mining industry; compliance monitoring and process monitoring. Compliance monitoring is reactive, that is, monitoring undertaken in order to comply with a license to operate. In this type of moni-toring, the mine waits for an exceedance of monitoring criteria to occur, and subsequently reacts to the outcome of the monitoring. Because compliance monitoring is required as part of the mining license, it is usually done without thought on the mines part. In compliance monitoring, only environmentally damaging param-eters are monitored.

Environmental Earth Sciences have audited a range of mines across Australia through which we review the monitoring undertaken, and perform a Gap Analysis to identify shortcomings in the monitoring. As a result of this experience, we have created a flow chart for identifying and categorising gaps in environmental monitoring programs. This chart is shown in flow chart to the left. We rarely find that the mandated monitoring is not undertaken (Category 1 Gap), but we frequently find it

Gap Analysis Process Flowchart

1.Is monitoring undertaken in accordance with associated potential risk?No

Yes

Category 1 Gap2.Is monitoring sufficient in design (frequency, type, location etc.) to address and mitigate potential risk?

No

Category 2 Gap

Yes

3.Is monitoring data/output information assessed, interpreted and managed to track risk alteration and evaluate the need for improved risk mitigation?

No

Yes

Category 3 Gap

No Gap identified

Monitoring piezometer installed at Mary Kathleen Mine to test seepage quality and rate. (Photo: Philip Mulvey)

Gap analysis process flow chart used to identify and define gaps in environmental monitoring systems.



is inadequate for the purpose, improperly located or incomplete (Category 2 Gap) or the monitoring results are not interpreted correctly or appropriately (Category 3 Gap). The problem with this type of monitoring is that it is seen as an externality that does not assist the process of mining; therefore it is undertaken for the lowest cost and thus becomes prone to the types of Gaps indicated above.

The type of monitoring undertaken to assist the process of mining is called process monitoring. Process monitoring actually saves the mine money over the life of the mine and, after initial set up, is often cheaper to run than compliance monitoring. The aim of process monitoring is to confirm the conceptual site model for closure by confirming that the type and rate of likely environmental impact is consistent with the model, and the mitigation measures are behaving as designed. Process monitoring is used to constantly calibrate the site conceptual model by generating real data to replace assumptions in the model.

Process monitoring also includes a designed response strategy, which is implemented if the rate and type of environmental impact is greater than the model predicts. Therefore, unlike compliance monitoring, process monitoring has contingencies built in at commencement, in case of adverse monitoring results. For a more detailed explanation of process monitoring and compliance monitoring, see Mulvey (1998).

Undertaking process monitoring substantially reduces the cost of closure and the post closure monitoring time by providing a greater understanding of the environmental impacts from mine waste, including the chemical reactions and width of the natural attenuation zone. This capacity to extrapolate into the future with surety provides assurance to the community and to regulators. As a result, process monitoring reduces scepticism and, if consistently applied, leads to the temporal based schematic as shown above in Example 2.

As seen in Example 2, two cost scenarios (green) are plotted progressively, representing: 1) a progressive bond release (release of bond subject to achieving certain benchmarks); and 2) a single release of the bond, (release of the bond at the end of the monitoring period). When comparing Examples 1 and 2, it can be

seen that constant calibration requires a small increase in costs during production, but substantially lower costs during closure, and a significantly reduced monitoring period.

Systematic management of mine wasteMost people have experienced the frustrating problem of comput-er failure, when the supplier of the hardware said that the problem was caused by the software that they did not provide, and the software provider said it was a hardware problem. Neither took responsibility for the breakdown. The consumer has now learnt that it is best to have only one supplier configure the computer and take responsibility for its performance. Mine waste suffers a similar hardware/software problem that has a substantial impact on the success of mine closure. It can be summed up as follows: mine designers do not supervise mine operation; audits of monitoring are generally for compliance, not

technical adequacy, and so audits may miss systemic issues that take a long time to appear or cause a problem;

ongoing monitoring is undertaken by a contractor for the lowest cost and therefore is limited to compliance monitoring. As such, opportunities to collect data for closure planning are missed;

contractors undertaking earthworks for closure did not design the closure plan and are usually paid per m3 of material shifted. Impacts from poor earthworks may take years to appear, by which time the contractor is gone.

The problem with this closure scenario is that there is no systematic involvement of key players in the mining team and their design consultants, and there is no incentive for the mine production team to meet and implement closure objectives throughout the mines operation. Consequently, no-one takes responsibility for closure throughout the life of the mine and mine managers have no incentive to do so.

A sceptical summary of key performance indicators (KPIs) of a Mine Manager in the past might have been:

Go as fast as you can, safely and cheaply with no environmental incidents.

Constant calibration of confidence and closure costs over the life of the mine.

Confidence

Cynicism Cumulative cost ($)

Design Operations Production ceases

Closure Monitoring

Expected maximum closure cost

(planning stage)

TIME

EXAMPLE 2: CONSTANT CALIBRATION

2

1

20



Note that there is no reference to being involved in an ongoing process of achieving, economical, environmentally-sound, swift closure. There is no incentive for process monitoring and no system to ensure it is part of the mine culture.

So how might mine managers be encouraged to become constantly aware of mine closure? One way is to offer them incentives to include closure in their KPIs by the creation of a mine closure levy. In this way the above mine managers KPI might be rewritten as:

Go as fast as you can, safely and cheaply with no environmental incidences, and achieve reduction in the closure

levy at the 3, 5, 8 and 12-year marks.

A closure levy is a type of user pays system, where the department or group that creates the waste (for example, the Mining Department) is responsible for properly handling and storing the waste in accordance with the conceptual site model. This is an internal process that should be controlled by the environment department of the mine using the following protocols: process monitoring, not compliance monitoring; prove initial conceptual site model assumptions with data; closure trials; and continual model calibration.

At the commencement of mining, performance benchmarks should be set based on replacing assumptions in the CSM with data and on calibration of the CSM. An example this is shown in the box to the right.

A Working example of Systematic Mine Waste Management

At commencement of mining, closure costs are estimated at $3/m3, for example. The mine makes provision for closure to this amount but applies an internal levy for closure. This starts at 400% of planned closure cost per tonne, assumed to be $3/m3 of waste rock/tailings. Thus $12/m3 for closure is allocated to costs. The environmental departments use the money to eliminate assumptions such as the acid/metal generation rate in the waste rock, and the attenuation processes and capacity of the natural environment to attenuate acid and metals. Once the agreed, data have been derived to eliminate assumptions in the model, the levy drops to the next level, say 250%. This occurs progressively at each bench mark until 100% of closure costs are put aside. Assumptions that will need to be eliminat-ed will include weathering rates, erosion potential, revegetation process and inputs to sustainability.

Measurement of runoff, seepage, weathering revegetation, plant colonisation, response to storms, dust and so on, can be used during the life of the mine for constant calibration of the conceptual site model. With the replacement of assumptions with real data and calibration of the conceptual site model, the closure levy can be reduced progressively to 250%; 175%; 150%; 125%; and 100%, as the agreed monitoring benchmarks are met for the conceptual site model.

The levy acts as an incentive for the mine management to increase profitability, and in doing so reduces the uncertainty associated with the site conceptual model for closure. This in turn increases the confidence of the authorities in the site con-ceptual model as a predictive tool for post closure environmen-tal impacts and therefore, reduces the post closure monitoring time.Conclusion

Today, not only is a social license to operate es-sential, but so too is a social license to close. For authorities to allow the successful relinquishment of a mining lease, it is essential for the mine operator to reduce uncertainty in the closure predictions re-garding future environmental impacts of mine waste. To achieve this requires the systematic constant management of mine waste and voids for closure by either mine management or a designer-contractor combination. Part of this systematic management is likely to include incentivising mine managers to be actively engaged in reducing uncertainty of the site conceptual model for closure.

ReferencesMulvey (1998) Conceptual model for groundwater

monitoring around tailings dams evaporation ponds and mills Groundwater Monitoring Mining Environment Magazine, July 1998 pp13-20.

Rising Tide (No Date), Boggabri ProtestPhoto, available at: http://www.risingtide.org.au/node/1165?size=_original

Sheldon, C.G. and Strongman, J.E. (2002) Its Not Over When Its Over: Mine Closure Around the World; Mining and Development, World Bank Group Mining Department, World Bank and Inter-national Finance Corporation.

Williams, Scott and Gerrard (2012) Rehabilitation Commitments for Pits and Waste Rock Stockpiles at Frances Creek Iron Ore Mine, ICARD 9 Pro-ceedings, Ottawa Canada, May 2012.

Modern mine tailings storage facility with clay dust cover placement over the inactive tailings cell, and tailings beaches in the active cell to encourage evaporation of water. (Source: Environmental Earth Sciences, 2012)



ABOUT THE AUTHORS

About Environmental Earth SciencesEnvironmental Earth Sciences is a specialist environmental geosciences firm that began operations as a consultancy firm, providing groundwater and environmental geochemistry to the mining industry in 1984, com-mencing with closure of uranium mines. With time, we have expanded to include contamination investigation and remediation and cap design to our service, in fact any aspect associated with the nurture, repair and sustainable utilisation of land. In order to pro-vide a better delivery of scientific innovation we expanded our services from consulting to include specialise contracting and research such that environmental Earth Sciences now comprises Three Operating Divisions providing services to the Mining Industry:

Consulting Environmental Earth SciencesResearch Centre for Contaminant GeoscienceContracting EESI Contracting

Professor Alan BakerProfessor Alan Baker heads the research division of the Environmental Earth Sciences International (EESI) Group, the Centre for Contaminant Geosciences. Professor Bakers experience includes pioneering roles in the fields of botany, biotechnology and particularly in phytoremediation.

Alan has pioneered the field of direct seeding and planting of salt and metal tolerant plant species into degraded land, tailings and waste rock in arid, temperate and sub-tropical climates.

Alan was Professor of Botany (Ecology and Environmental Science) at the University of Melbourne from 20002008, where he headed the Applied Ecology Research Group in the School of Botany. His group was involved in restoration and revegetation projects of mineral wastes, remediation of contaminated land and phytocapping of landfill sites, in addition to carrying out fundamental research on heavy metal uptake and accumulation and on the development of new phytotechnologies. On retirement from the University of Melbourne in 2008 he has been made an Honorary Professorial Fellow, and Visiting Professor at the Centre for Mined Land Rehabilitation (CMLR) at the University of Queensland and the Department of Animal and Plant Sciences at the University of Sheffield, UK.

He is a Fellow of the Linnean Society of London, and of the UK Society of Biology, and is a Founder Member of the UK Institute of Ecology and Environmental Management; elected Fellow 2004. In addition to extensive work experience in Europe, Australasia and the USA, he has worked in many developing countries including The Philippines, Thailand, New Caledonia, Sri Lanka, PR China, Democratic Republic of Congo, Brazil, Costa Rica, Cuba and Chile. He is the author of 180 original scientific papers and articles and holds 3 patents. Professor Baker was Editor-in-Chief (Inorganic Contaminants) of the International Journal of Phytoremediation 1999-2009.

Contact:CENTRAL REGION

SydneyPO Box 380, North Sydney NSW 2059

Ph: +61 2 9922 [email protected]

office also in Orange

SOUTHERN REGIONMelbourne

PO Box 2253, Footscray VIC 3011Ph: +61 3 9687 1666

[email protected]

NORTHERN REGIONBrisbane

PO Box 3207, Newstead QLD 4006Ph: +61 7 3852 6666

[email protected] also in Ballina

Philip MulveyPhilip is the Chief Executive Officer of Environmental Earth Sciences and Technical Director of Centre for Contaminant Geoscience. Philip is a specialist in soil and water chemistry as well as interactions between the two media. He has over 30 years experience in environmental geochemistry and hydrogeology

in the mining industry in both Australia and overseas. He also has experience in contamination, landfill design, management and decommissioning; and investigation, amelioration of acid sulfate soil and is a statutory auditor in four states. Often, in so doing, providing innovative new solutions that have impacted on industry practices. He has several registered patents in soil remediation and carbon sequestration.

Peter ScottPeter is a Senior Principal Environmental Geochemist, with over 35 years experience in the mining and mineral exploration industries in Australia and Asia Pacific region in geology, applied geochemistry, and data analysis. He is a leading specialist in the assessment, management and mitigation of acid, metal, and saline drainage.

Peter specialises in mining waste management projects, waste rock characterisation studies, leachate control and modelling, baseline studies for monitoring leachate development from mine waste, rehabilitation and remediation of mine waste facilities, and development of environmental management plans for life of mine operation. He has extensive project management experience and supervised acid drainage remediation projects in the gold and base metals mining, coal mining industries. He has undertaken forensic geochemistry studies to determine the location and quantify distribution and volumes of reactive mining waste within existing waste rock storages to enable effective cover design, remediation and closure.

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