24-MMP-A4 Mine Valuation and Mineral Resource Estimation · December 2014
Nivaar worked solution (AI-drafted; not reviewed by a licensed engineer)
EGBC National Exam — Mining and Mineral Processing Engineering, 09-Mmp-A4 Mine Valuation and Mineral Resource Estimation, 2014-Dec. 3 hours duration; one handwritten 8.5×11 in reference sheet permitted (not an open-book exam); only approved Sharp or Casio calculators allowed. Question 1 is compulsory (40 marks, parts 1.1–1.7); candidates then select FOUR of the six optional Questions 2–7 (15 marks each) to complete the paper.
Reference texts: Isaaks & Srivastava, An Introduction to Applied Geostatistics (variogram modelling, kriging estimators, volume–variance relations); Hustrulid, Kuchta & Martin, Open Pit Mine Planning and Design (mine valuation, NPV and cut-off grade methodology, mineable reserves); Gentry & O'Neil, Mine Investment Analysis (Canadian mining taxation, smelter/refining contract terms, net smelter return); SME Mining Engineering Handbook, 3rd ed. (mineral exploration/evaluation stages, ore reserve classification); CIM Best Practice Guidelines and NI 43-101 (Canadian Securities Administrators).
Question text not reproduced: the examination questions are © Engineers and Geoscientists BC. Open the official past paper (linked at the top of this page) to read the question, then follow the worked solution below.
Capital Cost Allowance (CCA). CCA is the Canadian Income Tax Act's regime for depreciating capital assets for tax purposes — the tax-deductible counterpart to book/accounting depreciation. Depreciable assets are grouped into prescribed classes, each with its own maximum annual declining-balance write-off rate; a taxpayer deducts CCA against income (up to the class maximum) each year, reducing taxable income without an actual cash outflow, and the undepreciated capital cost (UCC) pool carries forward. CCA is the primary mechanism by which mining capital expenditure (plant, mill, mobile equipment, mine development) shelters early-year taxable income.
Class 41 rate. Most mining-related depreciable property (mine plant and equipment, and pre-2017 mine development in Class 41(a)) falls in Class 41, with a base 25% declining-balance CCA rate. Certain new-mine and major-expansion assets historically qualified for an additional allowance that could increase the effective annual write-off — permitting the taxpayer to claim enough CCA to reduce income from the mine essentially to nil in the early years of production, an accelerated-recovery feature specific to the mining sector intended to reflect the high up-front capital risk of mine development.
Class 41(a) — commencement of production vs. availability for use. The federal "available for use" rule generally restricts CCA claims until an asset is put into use (or, absent use, until roughly two years after acquisition) — a general anti-deferral rule across all CCA classes. For mining assets specifically, "commencement of commercial production" (tested, per the exam's own Question 1.1 answer, by the first 90-day period at ≥60% of rated mill capacity) is the pivot date that separates pre-production development expenditure (largely non-depreciable Canadian Development/Exploration Expense pools) from post-production Class 41 capital assets eligible for the accelerated additional allowance. Provincially, mining tax regimes (e.g. BC Mineral Tax, Ontario Mining Tax) apply their own, generally separate, processing-allowance and new-mine-tax-holiday rules keyed to their own commencement-of-production definitions, which do not always align exactly with the federal test — a mine can therefore reach "commercial production" for provincial mining-tax purposes on a different date than it reaches "available for use" for federal CCA purposes, requiring separate tracking of both thresholds.
