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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…)
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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 within a few decades 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 a 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
Use of: GOLD 2007 use in tons excluding central banks Natl. Geog. 2009 Over half of the world’s gold has been extracted in the last 50 years 14
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
U.S. Consumption Trends Minerals 8 McKinney and Schoch 1998
MINING Brazilian Iron Mine, Belo Horizonte 9
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 12
Copper Mining and Production McKinney and Schoch 1998 13
Problems: Social Issues • Large and small scale mining: • Environmental destruction • Waste production • Onsite pollution • Offsite pollution 15
Onsite and offsite pollution: Tanks are needed to trap runoff or toxic solutions--leaks can happen 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. 19
Asarco Smelter, Tacoma 22
54 ppm 1 ppm 1 ppm Cd 7 ppm Zn 46 ppm 5200 ppm 23
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 27
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… A license to steal? 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 30
US stockpiles of strategic metals and metal ores. Strategic metals and minerals: materials a country does not produce itself but are considered essential for materials or processes 31
Mineral resources are nonrenewable resources Two fundamental strategies for dealing with mineral scarcity: 1. Increase supply 2. Decrease demand 33
sinks sources 34
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 P x A x T = I 35
Metal/Mineral Resource Conservation 1. Increase supply recycle old materials -- saves on resources and in some cases, saves energy 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 buyingDURABLEGOODSis an easy way to reduce demand for mineral resources 38
Mineral Resources High extraction costs, and not all environmental costs are included 39
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 the amount of waste and environmental restoration needed due to pollution associated with resource use 40