Mining in Ecologically Sensitive Landscapes

Mining in Ecologically Sensitive Landscapes

Mining in Ecologically Sensitive Landscapes explores the interface between geology and botany, and mining and conservation. Many areas of unusual geology that contain ore-bearing bodies also support unique ecological communities of plants and animals. Increasing demand to exploit rich mineral deposits can lead to a conflict between mining and conservation interests in such landscapes.

This book brings together experts in the field of mining and conservation to grapple with this pressing issue and to work toward a positive outcome for all. Chapters are grouped into four themes: Introduction, Concepts and Challenges; Endemism in Ironstone Geosystems; Progress in Bauxite Mining; and Ways Forward.

The book focuses on natural and semi-natural ecosystems, where landscape beauty, biodiversity and conservation value are at their highest measure and the mineral wealth they contain can bring affluence of regional or even national importance. Examples of conflicts ranging from threatened floristic endemics to human ecology are included, from Africa, the Americas and Australasia.

Mining in Ecologically Sensitive Landscapes is an important reference for environmental managers, NGOs, restoration ecologists, academics, undergraduate and postgraduate students of ecology and environmental studies, conservation biologists, as well as mine managers, mining environmental specialists, consultants, regulators and relevant government departments.

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      Abstract

      Many areas of unusual geology that contain ore bearing bodies also support unique ecological communities of plants and animals. In such landscapes, increasing demand to exploit rich mineral deposits can lead to a conflict between mining and conservation interests. This book brings together expert commentary in the fields of mining and conservation to grapple with this pressing issue and to work towards a positive outcome for all. The book is divided into four sections, where issues are dealt with in a series of case studies spanning four continents. The first section provides an introduction to concepts and challenges of mining in ecologically sensitive landscapes. The second section deals with rarity and endemism in plant species found on highly sought after (for mining) ironstone geosystems. The third section focuses on progress that has been made in restoring biodiverse forest after bauxite mining. The final section considers ways forward, away from conflict. Mining in Ecologically Sensitive Landscapes aims to generate an awareness of some of the key issues through a series of case study exemplars of this complex yet globally critical issue, one that wider society rarely considers in informed terms.

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      Abstract

      The demand for energy throughout the world grows each day, and coal will be needed to meet a large portion of that demand. Coal mining techniques in the Appalachian and Midwestern coalfields have evolved to mine larger land areas and multiple seams at greater depths. New reclamation methods and approaches must also evolve to minimise cumulative impacts on aquatic, terrestrial, and human resources. Mined land reforestation practices over the past 80 years illustrate the evolution of reclamation in the eastern coalfields of the USA Prior to the implementation of the Surface Mining Control and Reclamation Act (SMCRA), tree planting was synonymous with reclamation. Grassland reclamation became the dominant approach post-SMCRA. As stakeholders of the mining and reclamation process have begun to appreciate the value of forest ecosystems, there is greater emphasis on ensuring land and forest restoration and proper ecosystem functioning on reclaimed mined land. A forestry reclamation approach is supplanting grassland reclamation where forests are the logical post-mining land use. Restoring forestland capability, native species, and watershed protection are positive outcomes. However, greater public demand for stream protection, water quality, biodiversity, carbon sequestration, native wildlife habitat, and human protection may require a more comprehensive ecosystem reclamation approach. In my view, the components of such an approach already have a good basis in science and could be applied through a process of adaptive management to help the coal industry in the USA maintain its social licence to operate.

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      Abstract

      As resources become scarcer, the mining industry will begin to place greater focus upon mineral deposits that are currently not subject to development because they are physically larger but of lower quality than existing major deposits or are contained within areas protected by virtue of their ecological value. Exploitation of these resources will create an increased risk of immediate environmental damage as well as long-term impacts on ecological and socio-cultural sustainability of the affected region. This can be interpreted as a potential future cost that is not generally considered adequately by the mining company or its regulators during mining operations and one that has historically been passed onto the public following mine closure.

      Using the Ranger uranium mine as an example, some of the hidden socio-cultural and ecological costs relevant to Australia’s ecologically sensitive Kakadu National Park are described. The principles used to describe these are then applied to other mining situations in Tanzania and Namibia, and discussed in terms of those countries’ regulatory systems. While there is a special focus here on uranium, many of the hidden costs that are identified are clearly applicable to other commodities although the quantum values of those costs may differ considerably.

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      Abstract

      Brazil includes some of the most important metal-rich regions in the world. In particular, its ferriferous formations represent almost 20% of global iron ore reserves. Besides its huge mineral potential, the geoecologic systems constituted by ferriferous formations and their mountaintop outcrops – locally known as cangas – also provide environmental services, such as water reserves, that are vital to society. Natural communities characterised by high local and regional diversities, together with speleological and paleoenvironmental sites, confer a high conservation value to these systems. Many components of the local flora are endemic to cangas, and their associated caves are characterised by peculiar trophic resources and a rich invertebrate fauna. In spite of their significant environmental heritage, iron-rich areas are among the most threatened ecological systems in Brazil, due to their restricted distribution in association with important iron ore deposits, and their poor representation in the National Protected Areas System. Their vulnerability is inherently high, since mineral rights to mining companies (from exploration licences to extraction permits) covers almost 100% of all known canga sites, threatening 166 rare plants. Furthermore, according to the National Mining Plan, the majority of iron ore reserves are scheduled to be mined in the next 29 years. In addition, there is paucity of research, public information and legal instruments to promote their protection. This is probably one of the most challenging scenarios for environmental conservation in Brazil.

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      Abstract

      A series of ancient subdued ironstone ranges stretch over 700 km from the edge of the species-rich south-west of Western Australia into the arid interior. This area, well to the south of the major iron ore producing region of the Pilbara, has had little systematic flora survey. Limited surveys in early 1990s indicated that some of these ironstone ranges were a repository for localised endemic plant species and restricted vegetation communities. Following the rapid growth in the price of iron ore and the expansion of iron ore exploration and mining in these ranges in the early 2000s, a major survey program was undertaken to document the biodiversity values of these ranges in order to provide a regional basis for the assessment of development proposals. Between 2005 and 2008 some 24 ranges were surveyed. These surveys initially concentrated in areas of high mineral prospectively but now cover a wide cross-section of the ironstone ranges across the Yilgarn Craton. The surveys have highlighted the unique nature of the vegetation on each range; the occurrence of species with distributions restricted to, or centred on these ranges; and have identified over 20 new species. These data illustrate the high biodiversity values of the ironstone ranges of the Yilgarn and will be integral in the assessment of future resource development proposals over the ranges.

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      Abstract

      Cliffs Asia Pacific Iron Ore operates the largest iron ore mining operation in the Yilgarn region of Western Australia. Mining commenced in 1994 at Koolyanobbing and expanded to include northern satellite mines at Windarling and Mt Jackson in 2004. Mining utilises multiple small, separate ore bodies to produce a blended product for export through Esperance port. Ore bodies are typically associated with low banded iron formations. Banded iron ranges are scattered across the region, forming islands of relatively distinct biodiversity, sometimes supporting flora with very restricted distributions. Where the location of ore bodies coincides with the distribution of such flora, this presents particular challenges. The hierarchy of ’avoid, minimise, mitigate’ in the management of environmental impacts is universally applicable for any mining development in any setting, but its importance is heightened in this particular environment. Examples of the application of this approach and its success in achieving the environmental objectives to date are presented. The Cliffs experience provides useful lessons with relevance to prospective mining projects in both the Yilgarn and Midwest regions of Western Australia, where there are a large number of emerging projects based on geologically similar deposits with similar biodiversity issues. The planning aspects are discussed, both in terms of minimising impacts at the local level and in balancing resource extraction and biodiversity conservation at the broader regional level.

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      Abstract

      The jarrah forest is a unique vegetation community restricted to the Darling Plateau in the south-west corner of Western Australia. It is flanked by the predominantly cleared coastal plain to the west and the almost totally cleared Wheatbelt to the east. Having a relatively undisturbed natural vegetation community close to Perth gives the area special significance. Alcoa is privileged to be allowed to mine in this sensitive environment and accordingly applies the highest standards of environmental management in its operations. Drinking water production, timber, conservation and recreation are the main land uses in the forest and restoration aims to reinstate these values after mining. Mining in this relatively intact natural ecosystem close to Perth requires high standards of environmental practice in all areas. This paper describes in detail, three significant aspects of environmental sensitivity and how they are managed: jarrah dieback disease, drinking water catchment and biodiversity impact.

      Management of jarrah dieback disease is backed by a strong history of applied research, both within and external to Alcoa. Management includes knowing where the pathogen is present, restricting vehicle movement from infested to uninfested areas, cleaning vehicles before entering uninfested areas, preventing infested and uninfested soils mixing, preventing water draining from infested to uninfested areas, training all field staff and planners, monitoring the spread of the disease attributable to mining, and investigating the causes. Extremely small rates of dieback disease spread due to mining have resulted from these management practices.

      Water catchment protection is underpinned by clear standards and protocols, government reporting requirements, continual monitoring, and high standards of earthworks and other engineering controls. Drinking water standards have never been compromised by Alcoa’s operations in Perth’s water catchment areas.

      Successful management and restoration of biodiversity stems from the concept that Alcoa’s mining is a transient land use and that mining is not complete until restoration has been carried out. Flora is successfully returned by maximising the diversity of species originating from the natural topsoil seed bank, applied seed and planting of difficult or ‘recalcitrant’ species. Fauna restoration requires the return of suitable habitat for fauna species as well as removal of any barriers to animal success, in particular feral animal predation. Alcoa funds feral fox control in the jarrah forest and is actively involved in rare species re-introductions in areas within and around its mining operations.

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      Abstract

      The ability of terrestrial orchids to recolonise ecosystems after total loss of vegetation is highly variable. Some orchids re-establish quickly, others are slow to return while some remain absent for at least several decades after disturbance. Orchid seed is minute, has been found to be readily dispersed and is not regarded as a limiting factor provided adequate rates of pollination occurs. A case study in the jarrah forest of Western Australia showed that compatible symbiotic fungi were present in a restored bauxite mine site, but inoculum levels were low and patchily distributed in soils. Comparative studies of orchids in disturbed ecosystems revealed key functional differences between early colonisers (disturbance opportunists) and disturbance intolerant species, especially concerning the degree of pollinator and fungus specificity. However more research is required to resolve the impact of microhabitats defined by soil and vegetation on orchid colonisation and how these factors change over time. In particular, there is a paucity of data on the ecological roles and habitat preferences of the fungi, and insects on which terrestrial orchids depend. Orchids that are early re-colonisers are indicators of disturbed habitats, while those that are disturbance intolerant and recolonise slowly are useful as indicators of habitats in excellent condition.

    3. Page 159
      Abstract

      The system of mining and restoration developed and used at the Rio Tinto Alcan Gove bauxite mine between 1973 and 2005 is described. By 2009, this system had been used to restore successfully more than 3000 ha of mined lands to ecosystems dominated by local native open-forest species. The major features of post-restoration development in these restored ecosystems are described, largely based on chronosequences of study sites extending to ~30 years. Over this period the plant community developed from a grassland to a shrubland to a closed forest and finally to an open forest. By 26 years, it possessed a similar three-tiered structure to the local native open forests (including the same dominant eucalypt species), together with diverse understory and herbaceous strata colonised by more than 170 species beyond the ~39 species sown. The few reported studies of the animal community have indicated rapid colonisation of the restored sites and ongoing community development within three key environmental indicator groups: ants, termites and birds.

      Due to fire exclusion, substantial litter layers have developed at the longer-restored sites and because of their magnitudes they may constitute a risk to the developing keystone canopy eucalypt species when eventually burned. Rapid soil development occurred contemporaneously, with substantial changes in physical properties and large increases in near-surface soil organic matter concentrations, from c. 10 g kg−1 C at planting to values greater than those present in the adjacent native forests. A wide diversity of nutritionally important ecto and arbuscular mycorrhizas were reported and appear to change with ongoing plant community development. Continuing development of these novel ecosystems seems assured but their future trajectory is likely to depend partly on management decisions relating to the institution of a firing regime concilient with a landscape subject to regular firing.

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      Abstract

      The unrealised resource of plant species naturally occurring on metalliferous soils (‘metallophytes’) could provide the minerals industry with an economic and sustainable means of mine site rehabilitation and effective progression towards mine closure. Rather than viewing mining solely as an industry that contributes to the destruction of metallophyte habitats and subsequent biodiversity loss, offsetting could be applied through the use of metallophyte species in the rehabilitation to not only be an effective way to mitigate the loss of habitat, but also to secure the survival of the metallophyte species themselves. Of the range of available phytotechnologies, phytomining offers the potential to capitalise on sub-economic ore bodies, particularly ultramafic regoliths. This technology could be complementary to conventional strip-mining methods as part of the subsequent rehabilitation strategy and presents a potential use for hyperaccumulator species in commercial “metal farming”.

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      Abstract

      The Goldfields region of Western Australia is one of the most geologically mineralised areas in the world, being particularly rich in gold, nickel and iron ore. It also contains the largest remaining temperate and semi-arid woodland on Earth. In this paper, we describe some of the outstanding natural values of the Great Western Woodlands (GWW). We then show why contemporary conservation methods, which aim to capture specific target levels of biodiversity in a ‘protected area system’, will not guarantee the persistence of biodiversity across this landscape. Instead, the region’s biodiversity can only be conserved by appropriately managing key ecological processes (e.g. fire, eco-hydrology, gross primary productivity, trophically important species) over the entire landscape. We argue that targeted research is required to identify what is needed to manage these processes. We describe the first phase of an initiative that works with all major stakeholders, including Traditional Owners, state and federal governments, local communities, non-government organisations and resource-based industry groups, which ultimately aims to forge a holistic longterm land use plan for the Great Western Woodlands.

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