Life Cycle Assessment (LCA) is a methodology used to measure the environmental impacts of a product or service across its entire life cycle, from raw material extraction through to end-of-life disposal. It accounts for all material, energy, water inputs, and emissions at each stage and evaluates their potential effects across categories such as climate change, acidification, eutrophication, human toxicity, and land use. LCA helps identify impact hotspots, compare alternatives, and design strategies to reduce environmental burdens.
In mining, LCA is particularly valuable because it enables a deeper understanding of the environmental consequences of operational decisions. For instance, it can be used to compare extraction methods, technologies, ore grades, and sites to determine which options have the lowest environmental footprint per unit of production. It also supports decision-making in mineral processing, waste management, energy efficiency, water conservation, mine closure, and rehabilitation. By applying LCA, mining companies can optimize resource use, minimize environmental impacts, and strengthen the social acceptability of their operations.
Conducting an LCA involves four main stages:
- Goal and scope definition: setting the objectives, scope, functional unit, system boundaries, and assumptions of the study.
- Inventory analysis: collecting and quantifying data on inputs and outputs at each life cycle stage.
- Impact assessment: applying models and indicators to estimate environmental impacts from the inventory data.
- Interpretation: analysing, communicating, and drawing conclusions from the results.
However, applying LCA in mining is challenging due to data availability, variability, and uncertainty. Reliable data can be difficult to obtain, especially for upstream and downstream stages. Inputs and outputs may vary widely depending on ore type, grade, location, operational practices, and even weather conditions. When multiple products or co-products are produced, allocation methods must be carefully applied to avoid misrepresenting environmental impacts. Sensitivity or scenario analysis is often needed to address variability and uncertainty.
To mitigate these challenges, mining operations should adopt best practices and established standards. The ISO 14040 and 14044 standards provide principles and requirements for conducting and reporting LCA, while the International Reference Life Cycle Data System (ILCD) offers methodologies, guidelines, and datasets that promote consistency and transparency.
