Mine closure is a very important step within the cycle of any mining asset. It requires proper financial planning and effective methodologies for valuation. Conventional approaches in the context of mining operations have traditionally included the use of deterministic approaches and static DCF NPV methods to estimate the cost of closure.
Nevertheless, these conventional approaches tend to undervalue the environmental liabilities and the costs of the asset retirement and care after closure. According to modern international accounting standards such as IAS 37 from IFRS, the mining company should make provisions for the closure as the present legal or constructive obligation measured at the best estimate of expected future cash flows. In addition, regulatory authorities require full financial guarantees or performance bonds to eliminate unfunded environmental liabilities.
Liability management needs to make an exact differentiation between various types of closure cost estimation. Mine operators keep LoA estimates for long-term planning purposes, Financial Liability estimates for balance sheet reporting under IAS 37, and Regulator estimate for environmental bonding.
The deterministic DCF NPV model faces challenges in estimating the costs associated with various types of liabilities due to artificial reduction in the cost that occurs when the distant outflows are discounted using high or fixed discount rates. Such a problem makes it hard for mine operators to do progressive rehabilitation and create a funding gap upon the end of life. As a result, there is a vulnerability of local communities to environmental threats.
As solution to valuation issues, practitioners recommend moving from deterministic models to probabilistic models. The probabilistic approach turns various uncertainties into a range of possible costs that allows mine managers to allocate contingency and perform progressive rehabilitation.
Mine closure planning in an integrated approach, otherwise known as “mining for closure,” ties environmental reclamation to operational planning schedules. Progressive rehabilitation helps reduce overall disturbance, provisions on balance sheets, and minimizes chances of facing legal or financial implications from emergencies.
Proper financial planning regarding mine closure protects companies’ balance sheets, ensures regulatory compliance, and preserves ecosystems in the area. Relying on the traditional Net Present Value (NPV) approach creates significant chances for under-bonding, undervaluing liabilities, and putting the company in financial difficulty during mine closure. Using probabilistic cost estimates, recognizing different liability systems, and including rehabilitation in operations may help increase the value of assets.
