By Dr Lorna Hernandez-Santin, Sustainable Minerals Institute
The future of mining may depend on the industry’s ability to lead environmental expectations that improve biodiversity outcomes.
Recent years have seen mainstream companies embrace ‘nature-positive’ or ‘biodiversity positive’ initiatives. These initiatives follow evidence that existing collective efforts have fallen short of halting biodiversity declines, parallel to the improved understanding of the biodiversity crisis.
Moving beyond neutralising species’ declines, the net positive initiatives intend to tackle the biodiversity crisis by reversing current trends of decline.
Expectations of mitigating impacts on biodiversity and the environment are not necessarily exclusive to mining. In the post-2020 global biodiversity framework, the United Nations’ Convention for Biological Diversity calls for “full integration of biodiversity […] across all levels of government and all sectors”.1
Nevertheless, we know mining does have environmental impacts that contribute to biodiversity decline. So how can the industry transition towards nature positivity?
A straightforward approach is by counteracting the highest environmental impacts from mining. The development of tools to aid in this endeavour are a key priority across research facilities and are readily becoming available for industry use.
Boosting post-mining rehabilitation
Ecosystem restoration can help to counteract habitat loss and degradation, while enhancing landscape connectivity can do the same for fragmentation.
Ecosystem restoration entails performing a range of activities to aid the recovery of self-sustaining landscapes. Within the mining industry, this involves mine rehabilitation practices and the improvement of offset areas.
In most countries around the world, rehabilitating mines is already standard practice, suggesting that a culture aiming to counteract habitat loss and degradation exists. However, current practices fall short of ensuring rehabilitation success in many cases.
Securing and enhancing landscape connectivity involves connecting land patches which, in turn, promotes long-term survival of species. These activities may include building wildlife crossings or improving resource availability (i.e. restoration) in smaller patches that link larger ones.
Scientists from the Centre of Mined Land Rehabilitation at the Sustainable Minerals Institute (SMI) have been working with industry to improve rehabilitation practices across the world. Such work has relied on the use and development of tools that can ultimately contribute to counteracting mining impacts on biodiversity.
Ecological monitoring tools
Appropriate monitoring of environments requires covering different aspects, including selecting suitable methods and scales (space and time). More specifically, adequate monitoring includes the choice of area, time intervals, ecological attributes and methods, which should allow comparisons within a particular land patch (over time) and across patches.
SMI researchers have been working on multiple projects to improve ecological monitoring using a combination of fieldwork and remote sensing techniques. SMI’s approach is to tailor tools and environmental monitoring techniques to each mine, where improvements in current practices lead to the most cost-efficient use of resources that safeguard rehabilitation success and create a rigorous path for progressive mine rehabilitation relinquishment.
An example from the landscape connectivity model. Image: UQ SMI
State and transition models
A state and transition model can help to illustrate what successful and unsuccessful rehabilitation trajectories look like over time. These models can be very helpful for the timely detection of deviations from the desired trajectory, which can trigger the use of management strategies to correct deviations more effectively.
Building state and transition models requires defining benchmarks for each state of the rehabilitation trajectory that consider two control types:
Positive controls consist of states along the desired trajectory, with the reference ecosystem representing the end goal
Negative controls consist of states along undesired trajectories, requiring data from previously rehabilitated areas with unsuccessful outcomes at the time of monitoring
In 2020, SMI published a state and transition model to aid the rehabilitation of the Ranger Uranium Mine, in the Northern Territory. This was done in collaboration with the Environmental Research Institute of the Supervising Scientist. The process of developing a state and transition model encompassed a literature review to understand the rehabilitation strategies of different mines of the Alligator Rivers Region, including the methods, successes and failures reported in this area. The team then used data collected during the literature review to build the state and transition model.
Rehabilitation report card
Due to differences in professional backgrounds, transmitting information from the environmental team to other organisational units of a mine can be difficult. This can lead to delays or uninformed decisions that impact the rehabilitation process and, therefore, result in ineffective strategies for mitigation or rehabilitation, or creates further impacts.
The rehabilitation report card is an information sharing system that allows environmental data and rehabilitation progress to be understood by decision makers and relevant stakeholders, regardless of their professional background. It can be considered a traffic light control to monitor the progression of rehabilitation, highlighting areas with success, those to keep an eye out for, as well as failures.
The rehabilitation report card system helps to support ecosystem restoration by improving understanding of the state of a rehabilitated area, leading to informed decisions across the mine. For example, the system helps to assign economic resources to environmental aspects as needed, allowing future budget forecasts to be allocated more efficiently.
SMI researchers have collaborated with Glencore to develop rehabilitation report card systems that have led to the government certification of their rehabilitation at seven different mines in Queensland and New South Wales.
Landscape photographed during fieldwork. Image: Dr Hernandez-Santin
Habitat suitability models
Habitat suitability models help determine the geographic areas that are most important for the modelled species, which can be used to mitigate impacts (e.g. areas to avoid). Fauna species are the most common target, but these models can be developed for other species such as vegetative ones.
Habitat suitability models are created using geographical locations of a species and a combination of environmental maps (e.g. topography, climate, vegetation, etc), at any scale (property to global).
Translating landscape connectivity
Landscape connectivity models determine areas where species are most likely to travel to and from remnant patches, as well as core areas of species presence.
Due to the scale of the fragmentation issues, connectivity assessments are regional. Once assessed, actions to enhance connectivity can be taken at the property or regional scale (across mine leases and/or other land uses).
The most effective actions to counteract fragmentation require coordinated efforts at a regional level to reach a common goal, such as a net positive outcome for biodiversity.
In a recent publication2, SMI researchers explored how different mine rehabilitation targets may influence the connectivity of the landscape for flora and fauna. As requested by Queensland’s Mine Rehabilitation Commissioner, the Fitzroy Region was used as a case study. The Fitzroy Region is home to a wide range of anthropogenic activities that have contributed to elevate its fragmentation, and it has one of the highest proportions of mining leases within Queensland.
The project compared how landscape connectivity would change if the rehabilitation targets of all mines in the region were set to either agricultural or native ecosystems. This required the development of two landscape connectivity maps, which were then compared to highlight the potential gains or losses in connectivity from either rehabilitation target.
Thresholds were added to the connectivity comparison maps, providing a decision-making tool that captures the potential of landscape connectivity (or the impacts to connectivity) and is easy to interpret by mining stakeholders of all professional backgrounds.
Nature-positive opportunities
Consider the mitigation hierarchy: avoid impacts, minimise impacts, rectify impacts, reduce remaining impacts and offset impacts. This hierarchy is ordered in preference of the mitigation strategy and is aligned with preferences from the nature-positive perspective.
There are examples of successful rehabilitation across the world which suggest that fulfilling mine rehabilitation expectations is possible. However, we can do better. Rehabilitation success can and should become synonym with mining.
To reach true nature-positive outcomes, the mining industry must upscale and improve current practices to ensure adequate rectification of impacts, as well as avoiding and minimising impacts in the first place. Under this mindset shift, reducing remaining impacts and offsetting them should be the last resort.
Moving towards nature-positive outcomes requires considering flora and fauna when applying the mitigation hierarchy and its associated strategies. Considering that the goal of ecological restoration is to achieve ecosystems where fauna can conduct their normal activities, the commonly used vegetation-centric approach essentially overlooks its goal. This is highly relevant, as lack of use by fauna implies unsuccessful outcomes and rehabilitation failure.
There are a range of opportunities to apply the mitigation hierarchy and approach impacts depending on the stage of a mine’s life.
Feasibility stage
The feasibility stage has a stronger focus on avoiding impacts.
Environmental impact assessments (EIA) are standard practice during this stage. These assessments help determine how removing, storing, processing and transporting resources may impact biodiversity. It can therefore be argued that EIAs contribute to understanding the level of impact from the habitat loss and degradation perspectives, at the property scale. However, current EIAs do not allow understanding of the cumulative impacts on a region, including issues of fragmentation.
GIS and remote sensing techniques offer an opportunity to incorporate understanding of cumulative impacts from habitat loss, degradation and fragmentation during the feasibility stage. This includes the use of tools such as habitat suitability models and landscape connectivity models, including the translation of landscape connectivity tool developed by SMI.
Planning stage
The planning stage has a stronger focus on mitigating impacts, but it may also aid in avoiding impacts.
Even if resources need to be extracted from a specific location, a company may choose the location of infrastructure for other activities within the mine (e.g. office buildings, processing, land strips, roads, etc). Thus, during the planning stage, a mine could use habitat suitability models and landscape connectivity models, including SMI’s translation of landscape connectivity tool, to detect and avoid areas of interest for a specific species or groups of species.
To consider options for net positive outcomes that mitigate impacts or to develop plans to rectify future impacts, a mine may use habitat suitability models, landscape connectivity models, SMI’s connectivity translation tool, and/or ecological monitoring tools.
Active mining stage
The active mining stage has a stronger focus on rectifying impacts, but it can also aid across the rest of the mitigation hierarchy. To rectify impacts, the focus may be on determining strategies for rectification efforts or commencing rectification itself when progressive rehabilitation is used.
Notably, early intervention is the best approach from a nature-positive perspective, as well as the most cost-effective use of a mine’s resources (including economic resources). The importance of early intervention applies to both rehabilitation efforts and management actions. For example, rehabilitation efforts will be most effective when using fresh soil applied soon after impact; thus, progressive rehabilitation is the best approach. Additionally, early detection of undesired rehabilitation trajectories can trigger management actions that require minimal costs compared to actions applied long after the deviation started.
During the active mining stage, tools used and/or developed by SMI can aid the development and monitoring of rehabilitation and management strategies. These tools include state and transition models, rehabilitation report cards and ecological monitoring tools. In addition, habitat suitability models and landscape connectivity models can be used to assess and mitigate further impacts and/or to provide a regional strategy to enhance biodiversity outcomes.
Closure stage
The closure stage has a stronger focus on rectifying impacts and reducing remaining impacts but may also involve mitigation of impacts and offsetting those that could not be eliminated. Notably, when progressive rehabilitation is possible, most of the impact rectification efforts would have commenced during the active mining stage. Ideally, this means that the process of rectifying impacts would already be polished by this stage, leading to greater rehabilitation success rates at closure.
The tools used and/or developed by SMI may be used to support rehabilitation efforts at the closure stage. Ideally, the tools that are mine-specific (at the lease or regional scales) would have been prepared during the active mining or earlier stages, leaving only implementation at this stage.
Through design
The nature-positive approach is aligned with societal expectations for responsible mining. Therefore, nature-positive approaches can help address the international biodiversity crisis and to improve the social perception and position of mining companies.
Achieving a nature-positive
outcome is possible through a range of tools that counteract the causes of species decline (i.e. habitat loss, degradation and fragmentation), particularly under strategies based on early intervention.
Dr Hernandez-Santin. SMI Communications team
The simultaneous use of the tools suggested here allow a move towards net positive outcomes throughout the life of mines. These tools promote positive rehabilitation outcomes and enhance efforts relying on ecosystem restoration and landscape connectivity at the property and regional scales.
Early intervention relies on adequate monitoring and an adaptive management strategy for timely identification of rehabilitation failures that trigger the implementation of the best corrective action. An early intervention approach is also aligned with the most cost-effective strategies of mine rehabilitation, which can contribute to saving millions of dollars through early mine relinquishment.
Footnotes:
- Post-2020 Global Biodiversity Framework: https://www.cbd.int/doc/c/409e/19ae/369752b245f05e88f760aeb3/wg2020-05-l-02-en.pdf
- Setting restorative goals with a regional outlook: Mine-rehabilitation outcomes influence landscape connectivity: https://www.sciencedirect.com/science/article/pii/S0301479724007643?via%3Dihub
Featured image: A mine’s footprint, as seen from the air. Image: Dr Hernandez-Santin
