Limestone Quarry Reserve Classification and Permit Renewal
You are valuing a limestone quarry for a bank considering a reserve-based lending facility. The quarry has a mining lease over 240 hectares and a 20-year life-of-mine plan. A consultant reports 38 million tonnes of measured and indicated resources, but only 21 million tonnes are converted to probable reserves; the remainder lies under a buffer zone where the local community has objected to blasting. The operating permit expires in 14 months and renewal is pending; the regulator has requested a revised dust-management plan. The company's cash-flow model assumes 1.8 million tonnes per annum, a 25-year mine life, and a flat real price of $42 per tonne, with a 9% discount rate. Current spot price is $38 per tonne; the forward curve is $40 for years 1-3, then $41. The bank asks for a 'bankable' valuation and a sensitivity table. The company has no hedging and the quarry's product is sold domestically.
1. Explain how you would classify and use the resources/reserves in the valuation, and why the company's 25-year life may not be supportable.
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The 38 million tonnes of measured and indicated resources are not all reserves. Only the 21 million tonnes classified as probable reserves have demonstrated economic viability and sufficient confidence for a base-case valuation. The material under the buffer zone should be excluded unless the community objection is resolved, permits allow blasting, and the material is converted to reserves after appropriate study. For a bankable valuation, the base case should use the probable reserves, not the total resource. At 1.8 million tonnes per annum, 21 million tonnes supports about 11.7 years of production, not 25 years. A 25-year life would require converting additional resources, securing access to the buffer zone, and renewing the permit. Those are not base-case assumptions. The valuer should reconcile the company's model to the reserve statement, show the reserve depletion schedule, and test the mine plan against the permit conditions. If the company insists on 25 years, the additional tonnes should be presented as a separate upside case with clear conditions, not as bankable reserves. The valuation should also reflect the permit expiry in 14 months and the dust-management condition as risks to the base case.
2. Recommend the valuation approach and key sensitivities, and describe how you would present the permit and community risks.
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A discounted cash flow approach is appropriate because the quarry has a finite reserve, identifiable capital and operating costs, and a life-of-mine plan. The base case should use probable reserves, the forward price curve rather than the company's flat $42, a discount rate that reflects the asset and country risk, capital expenditure, rehabilitation, tax, and working capital. The valuer should not rely on a single point. Sensitivities should include price at the spot and forward levels, throughput, operating cost, discount rate, capital cost, reserve conversion, and permit delay. A bankable case should also include a downside scenario where the permit is delayed or granted with stricter dust conditions, reducing production or requiring additional capital. Permit and community risks should be presented as explicit assumptions and conditions: the permit expires in 14 months, renewal is pending, and the buffer-zone objection is unresolved. The report should state that the base case assumes timely renewal and no access to the buffer zone, and should show the value impact of a six- or twelve-month delay. The community risk should be described with the specific mitigation required, not as a generic disclaimer. The sensitivity table should allow the bank to see which assumptions drive the valuation.