The U.S. mining industry consists of the search for, extraction, beneficiation, and processing of naturally occurring solid minerals from the earth. These mined minerals include coal, metals such as iron, copper, or zinc, and industrial minerals such as potash, limestone, and other crushed rocks. Oil and natural gas extraction (NAICS code 211) is not included in this industry. Metals and other minerals are an essential source of raw materials for the U.S. building and chemical industries and are also a critical part of the production of everyday electronics and consumer products. For example, over 65 different minerals are required to produce a modern computer. Furthermore, coal accounts for nearly 50% of electric power generated in the United States.1
In 2006, the U.S. mining industry produced shipments worth $78.65 billion (excluding oil and gas).2
The mining industry plays an important role in all 50 states. In 2009, an estimated 1,400 mines were operating in the United States.1 As a supplier of coal, metals, industrial minerals, sand, and gravel to businesses, manufacturers, utilities and others, the mining industry is vital to the well being of communities across the country. The map below shows a distribution of types of mining in the United States.
Production and Supply
The United States is the world's second leading producer of coal, accounting for nearly 17% of world production. About 1 billion tons of coal is produced annually in the United States.1 The United States is also the world's leading producer of beryllium, soda ash, and sulphur, and the third largest producer of gold and copper.1 In 2006, the U.S. mining industry processed 1,162.8 million tons of coal, 59.4 million tons of metals, and 3,128.9 million tons of industrial minerals.
Minerals are mined either underground or through surface methods like open-pit mining. Approximately 66% of coal and 97% of non-fuel minerals are extracted through surface mining methods. Both mining methods go through a process involving three general stages. The first stage is extraction, which includes blasting and drilling to loosen and remove material from the mine. The second stage is materials handling, which involves transporting the ore and waste from the mine to the mill or disposal area. The third stage, beneficiation and processing, occurs at the processing plant. This stage recovers the valuable portion of the mined material and produces the final marketable product. Beneficiation operations primarily consist of crushing, grinding, and separations, while processing operations involve smelting and/or refining. Each of these stages is dependent on large amounts of energy from varying sources, including electricity and diesel fuel.
The mining industry consumed an estimated 551 trillion British thermal units (Btu) in 2002.3 Major energy sources include fuel oil, electricity (purchased and produced on-site), coal, and natural gas. The energy-intensive nature of mining is evident by the recovery ratio of the various materials being mined. Coal, with an average recovery ratio of 82%, requires the mining of 1.2 tons of material to recover 1 ton of coal. Industrial minerals have an average recovery ratio of 90%, while metals have an average recovery ratio of 4.5%. Thus, to recover 1 ton of metal, 22 tons of material will need to be mined.
Minerals are essential to nearly every aspect of our lives and our economy. Key markets include utilities, the primary metals industry, non-metallic minerals industry (glass, cement, lime), and the construction industry.
Mining operations are often the leading employers in the communities where they operate. More than 500,000 people work directly in the U.S. mining industry.1 The industry also indirectly supports an additional 1.8 million jobs in manufacturing, engineering, and environmental and geological consulting.1 Each coal mining jobs provides an additional 3.5 jobs elsewhere in the economy, and coal miners make an average of $73,000 annually.1
1 National Mining Association
2 Annual Survey of Manufactures, U.S. Census Bureau
3 Manufacturing Energy Consumption Survey