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Mineral Resources and Resource Management Resources: raw materials taken from the environment and used by society Types of mineral resources: Metallic ferrous (Fe and related metals) nonferrous (gold, copper, etc.) Non metallic structural (stone, gravel, sand…) industrial (salts, sulfur, asbestos…) Ornamental Energy (coal, uranium, oil….) Mineral resources are nonrenewable resources Renewable resources can be replenished 2 Our modern technological society is very dependent on mineral resources. The average person in an industrialized nation uses about 2.3 times as much Al and 1.3 times as much Cu as the typical person did 30 years ago. We use over 20 times more Al and 16 times more Cu per person than people in developing countries. 3 4 Metal use 5 U.S. Consumption Trends Minerals McKinney and Schoch 1998 6 World consumption of minerals has quintupled since 1945. Some minerals have been used to build roads, buildings and durable goods, but much has gone into disposable goods. McKinney and Schoch 1998 Per capita consumption of mineral resources by Americans 7 MINING Brazilian Iron Mine, Belo Horizonte 8 Utah copper mine 9 Australian coal mine 10 A few definitions…. Overburden: soil and rock covering a mineral deposit-normally waste material Tailings: ground up rock residue after the high-grade ore has been extracted Smelting: process of concentrating ore by heating to produce crude metals Slag: fused waste produced during removal of metal from its ore Refining: chemical purification 11 Copper Mining and Production McKinney and Schoch 1998 12 A gold mine with ore processing on site 13 Problems: Environmental destruction Waste production Onsite pollution Offsite pollution 14 Onsite and offsite pollution 15 Onsite and offsite pollution: Tanks are needed to trap runoff or toxic solutions--leaks can happen 16 The Holden Mine, Wash. 17 Holden Copper Mine -- operated almost 20 years, closed in 1957; within US Forest Service land Produced: 212 million pounds of Copper 40 million pounds of Zinc 2 million pounds of Silver 600 thousand ounces of Gold From: 10 million tons of ore Ore shipped to ASARCO smelter, Tacoma Smelter originally for lead, converted to copper in 1915; smelter closed in 1985. Now a superfund site. 18 19 20 Asarco Smelter, Tacoma 21 54 ppm 1 ppm 1 ppm Cd 7 ppm Zn 5200 ppm 46 ppm 22 Kam Kotia Cu/Zn Mine, Timmins Ontario (1943-1972) Restoration of Kam Kotia mine underway using Canadian Abandoned Mine Rehabilitation Funds Est. cost of $20 million Acid leachate from Kam Kotia Mine (pH 2-3) 25 Reshaping the land and replanting after iron mining in Brazil--housing development and golf course will be built 26 The General Mining Act of 1872 Miners can stake claims on public land and take minerals for free Claimholders can buy land ($2.50-4.00 per acre). Once paid, the owner can do as they please with the land. Nevada--$20 billion in minerals for $9000 Colorado--7000ac purchased for $42,000 and resold for $37million BLM estimate: $4 billion in minerals per year free Mine industry: Metal mining is risky and expensive; US could become dependent on foreign supplies But coal, oil and gas pay royalties… 27 Seattle PI, 11 Jun 2001 28 Mineral Prices Mineral prices are artificially low. Current mineral prices include only extraction costs -- not the costs of land, ore and other factors Over the last few decades, known reserves for many metals have grown as fast or faster than production. Governments have traditionally subsidized mineral production for several reasons: export currency to reduce international debt economic development national security 29 US stockpiles of strategic metals and metal ores. 30 The Global Metal Trade 31 Mineral resources are nonrenewable resources Two fundamental strategies for dealing with mineral scarcity: 1. Increase supply 2. Decrease demand 32 Resource Management Conservation Waste Reduction (Input management) (Output management) Reuse and Recycle Restoration Reduce Improved Efficiencies Substitutions sources Remediation Used by Society Removal sinks 33 Principles of Resource Management The 3 R’s: Reduce demand (substitutions, greater efficiency) Reuse Recycle Population x Consumption x Technologic = Environmental per person impact per unit impact of (Affluence) of consumption population Px A x T = I 34 Metal/Mineral Resource Conservation 1. Increase supply in recycle old materials -- saves on resources and some cases, saves energy 35 Energy for production 36 Metal/Mineral Resource Conservation 1. Increase supply recycle old materials 2. Decrease demand reuse goods increase prices to reflect environmental costs find alternatives or substitutes eliminate need through technology or lifestyle changes produce durable goods Producing and buying DURABLE GOODS is an easy way to reduce demand for mineral resources 37 Mineral Resources Cheap Resource High use by Society Cheap to Costly Disposal High extraction costs, and not all environmental costs are included 38 Key Points: mineral resources are nonrenewable--they include metallic, non-metallic, ornamental and energy minerals environmental problems associated with mining include on- and off-site pollution, environmental destruction and solid waste production mineral prices are artificially low for a variety of reasons such as national security, economic development resource conservation methods include recycling, substitution, eliminating demand, and producing more durable goods rather than disposable goods the 3 R’s (reduce, reuse and recycle) can also reduce 39