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Geologic Studies of Mercury by the U.S. Geological Survey

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Geologic Studies of Mercury by the U.S. Geological Survey FOLD BLEED BLEED BLEED BLEED Gray, ed.— Gray, Geologic Studies of Mercury by the Geologic StudiesofMercurybytheU.S.GeologicalSurvey—U.S.SurveyCircular1248 U.S. Geological Survey U.S. Geological Survey Circular 1248 U.S. Department of the Interior Printed on recycled paper U.S. Geological Survey BLEED FOLD BLEED BLEED BLEED Geologic Studies of Mercury by the U.S. Geological Survey Edited by John E. Gray U.S. Geological Survey Circular 1248 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior Gale A. Norton, Secretary U.S. Geological Survey Charles G. Groat, Director U.S. Geological Survey, Reston Virginia 2003 For sale by U.S. Geological Survey Information Services Box 25286, Denver Federal Center Denver, CO 80225 For more information about the USGS and its products: Telephone: 1-888-ASK-USGS World Wide Web: http://www.usgs.gov/ Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government Although this report is in the public domain it contains copyrighted materials that are noted in the text. Permission to reproduce those items must be secured from the individual copyright owners. Foreword It is the goal of the U. S. Geological Survey (USGS) to enhance and protect the quality of life by describing and understanding the Earth around us. This volume summaries selected geologic studies of mercury in the United States by the USGS. The six geologic studies report concentrations of mercury in coal, sediment, soil, water, air, and fish; and discuss how the USGS is evaluating some of these areas of potential environmental mercury contamination. This collection of studies represents only a small portion of the ongoing worldwide research on mercury, and is not intended to be a comprehensive reference on the geochemistry of mercury. Numerous other mercury studies are in progress in the USGS, in other governmen- tal agencies, in industry, and at universities throughout the world. These studies address the USGS Mineral Resources Program goal, which is to gain an understanding of the influence of mineral deposits, mineralizing processes, and mineral-resource development on environ- mental integrity, ecosystems, public health, and geologic hazards. Kathleen M. Johnson Mineral Resources Program Coordinator Contents Introduction, by John E. Gray .......................................................................................................... 1 Mercury in Coal and Mercury Emissions from Coal Combustion, by Robert B. Finkelman... 9 Mercury Mine Studies Environmental Impact of Mercury Mines in the Coast Ranges, California, by James J. Rytuba .................................................................................................................. 13 The Southwestern Alaska Mercury Belt, by John E. Gray and Elizabeth A. Bailey...... 19 Studies of Mercury Contamination from Gold Mining Mercury Contamination from Hydraulic Gold Mining in the Sierra Nevada, California, by Michael P. Hunerlach and Charles N. Alpers............................................. 23 Mercury in the Carson River Basin, Nevada, by Stephen J. Lawrence .......................... 29 Volcanic Emissions of Mercury, by Todd K. Hinkley.................................................................. 35 Summary, by John E. Gray.............................................................................................................. 39 Figures 1. Schematic diagram of mercury ........................................................................................... 2 2–4. Photographs showing: 2. Gold pan containing elemental mercury.................................................................... 3 3. Cinnabar sample............................................................................................................. 3 4. Inactive mercury mine in Nevada ...............................................................................4 5–7. Diagrams showing: 5. Production of some mercury mines of the world ..................................................... 5 6. Major species and transformations of mercury in the environment .................... 5 7. Aquatic mercury cycle showing important mercury species ................................ 6 8. Photograph of coal-fired electrification power plant near Farmington, New Mexico............................................................................................................................ 9 9. Map showing distribution of mercury in coal fields in the United States ................. 10 10. Scanning electron micrograph of mercury selenide (HgSe) crystals in lignite coal from California ................................................................................................. 11 11. Map showing mercury mineral belts in North America ................................................ 14 12. Map showing mercury deposits in California mercury mineral belt ........................... 15 13. Photograph showing typical mercury mine-waste calcines ........................................ 16 14. Diagram showing total mercury concentration in acid-rock drainage as a function of chloride concentration in the California mercury mineral belt ........................................................................................................................... 16 15. Map showing location of mercury mines in southwestern Alaska ............................. 20 16. Photograph of elemental mercury spilled at Red Devil mine retort, Alaska ................................................................................................................................. 20 17. Diagram showing concentration of mercury versus methylmercury in unfiltered water samples collected from near mercury mines and uncontaminated baselines in southwestern Alaska...................................................... 21 18. Diagram showing mercury concentration in muscle for fish collected in southwestern Alaska ...................................................................................................... 22 V VI 19. Map showing location of gold and mercury mines in California................................ 24 20. Photograph showing water cannons used to break down gold-bearing gravel deposits in the Sierra Nevada ............................................................................. 25 21. Photograph showing gravel deposits being washed into sluices.............................. 25 22. Diagram showing transport of mercury from a hydraulic mine pit through a drainage tunnel and discharge into creeks and rivers ............................. 26 23. Photograph of sluice system, Siskiyou County, California........................................... 26 24. Map showing location of sample sites in the Carson River basin, Nevada................................................................................................................................. 30 25–29. Photographs showing: 25. View of Carson River in Dayton Valley ................................................................... 31 26. Vivian quartz mill on Carson River........................................................................... 32 27. Vapor and steam emanating from the Volcano Farallon de Pajaros, Mariana Islands ......................................................................................................... 35 28. Volcanic emissions from White Island, New Zealand ......................................... 36 29. USGS scientists collecting volcanic gas samples ............................................... 37 Tables 1. Contributions of mercury to the atmosphere from natural and anthropogenic sources ........................................................................................................................................ 2 2. Geologic and geochemical factors that control the composition of mine drainage from mercury deposits and mines in the California Coast Ranges ................ 15 3. Mercury and methylmercury concentrations..................................................................... 40 Introduction By John E. Gray Mercury in the Products We Use because they have such a large volume of water. Mercury also evaporates from lakes and oceans, again contributing mercury to A liquid at room temperature, mercury is a unique metal the atmosphere, completing the cycle. with unusual properties. Elemental mercury has long been used in thermometers because it responds to changes in temperature. In fact, mercury’s many diverse properties have made it useful for many products. Mercury is a good metallic conductor with a Where Mercury Comes From low electrical resistivity; it has been used in electrical products including electrical wiring and switches, fluorescent lamps, mer- Mercury has been mined for more than 2,000 years and cury batteries, and thermostats (Eisler, 1987). Mercury also is most of the mercury used historically by man has been pro- used in navigational instruments to measure changes in tempera- duced through the mining of ore. Although mercury constitutes ture and pressure. In the medical field, mercury is used as a less than 1/100,000,000 of one percent of the Earth, and like component in dental fillings and as a preservative in many phar- many minerals and elements found in nature, mercury can be maceutical products. Mercury has been used in industrial and highly enriched in certain rocks called ore deposits. The most agricultural applications such as in the production of chlorine common
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