Energy Resources Program
Monday, May 09, 2016
Monday, February 29, 2016
Eight density separates of Permian Highveld (#4) coal were investigated for partitioning of Hg and trace elements. The separates include float fractions obtained in heavy media having densities of 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, and 2.0 g/cm3, and the sink fraction for 2.0 g/cm3...
Thursday, September 24, 2015
Monday, September 21, 2015
Tuesday, June 30, 2015
Press Release & Publication
The amount of water required to hydraulically fracture oil and gas wells varies widely across the country, according to the first national-scale analysis and map of hydraulic fracturing water usage detailed in a new USGS study accepted for publication in Water Resources Research, a journal of the American Geophysical Union.
Wednesday, May 13, 2015
USGS Publication: Fact Sheet 2015-3037
Coal ash is a residual waste product primarily produced by coal combustion for electric power generation. Coal ash includes fly ash, bottom ash, and flue-gas desulfurization products (at powerplants equipped with flue-gas desulfurization systems). Fly ash, the most common form of coal ash, is used in a range of products, especially construction materials...
Thursday, January 08, 2015
Outside Publication: Environmental Geochemistry and Health
Mountaintop removal mining (MTM) is a widely used approach to surface coal mining in the US Appalachian region whereby large volumes of coal overburden are excavated using explosives, removed, and transferred to nearby drainages below MTM operations. To investigate the air quality impact of MTM, the geochemical characteristics of atmospheric particulate matter (PM) from five surface mining...
Wednesday, December 17, 2014
USGS Publication: Open-File Report 2014-1153
Mercury (Hg) analyses were obtained in USGS laboratories for 42 new samples of feed coal provided by Eskom, representing all 13 coal-fired power stations operated by Eskom in South Africa. This sampling includes results for three older power stations—Camden, Grootvlei, and Komati—returned to service starting in the late 2000s...
Monday, September 22, 2014
Outside Publication: Journal of Coastal Research
Historic wetland losses along the Gulf of Mexico coastline have long given support to the idea that the observed changes do not follow the conventional marine erosion of a quasi-stable continental mass. Deterioration of the Mississippi delta is no exception. In an assessment of 33 of the major deltas in the world, Syvitski et al. (2009 found that 85% of them face areal reduction...
Environmental Geochemistry assesses the impacts of energy resources on the environment using a primarily geochemical/geologic approach. Energy resources contain substances that, when mobilized into air, or natural waters (surface and ground water), deposited/adsorbed on soils or sediments, or incorporated into foodstuffs, pose a potential environmental and human health risk. The project examines environmental impacts of toxic substances mobilized from: (1) energy resources in the geologic environment, (2) the extraction, transport, storage, and utilization of energy resources, and (3) the disposal of energy waste products.
Bill Orem Project Chief
Mercury (Hg) is a toxic pollutant with a complex biogeochemical cycle allowing it to be transferred between different ecosystem reservoirs and occur in different chemical forms that control its behavior and toxicity. In its elemental form, gaseous Hg has a long residence time in the atmosphere, up to a year, allowing it to be transported long distances from emission sources. Mercury can be emitted from natural sources such as volcanoes, or from anthropogenic sources, such as coal-fired power plants. In addition, Hg on the Earth’s surface from all sources can be re-emitted from land and sea back to the atmosphere, and then re-deposited. Mercury in the atmosphere is present in such low concentrations that it is not considered harmful. However, once Hg enters the aquatic environment, it can undergo a series of biochemical transformations that convert a portion of the Hg originally present to methylmercury, a highly toxic organic form that accumulates in fish and birds. In the U.S., consumption of fish with high levels of methylmercury is the most common Hg exposure pathway for people, leading to fish consumption advisories in every state (Fig. 1). Researchers in the USGS Eastern Energy Resources Science Center and their colleagues are actively involved in studying the behavior and occurrence of mercury in the environment, and especially, mercury sources and control from energy use (Kolker et al., 2012).Figure 1. U.S. water bodies for which the Environmental Protection Agency has issued mercury fish consumption advisories in 2010.
Allan Kolker Project Chief
Selenium is a naturally occurring element and an important micronutrient essential for all living organisms. Selenium is also used in many commercial applications including glass decolorizing, metallurgical additives, machining of ferrous and nonferrous alloys, pigments, copier photoreceptors, and in semiconductor and photocell industries. Although selenium is essential, large concentrations can be toxic, particularly to aquatic wildlife. Human activities such as coal mining, industrial processing, agricultural runoff and leaching of natural soluble selenium can concentrate selenium in excess of the regulatory limits of 5 micrograms per liter (µg/L) and affect wetland habits. The USGS Energy Resources Program researches the geologic location, extent and distribution, and environmental affects on human health and the landscape and provides this information to decision-makers.
Frequently Asked Questions Pertaining to Selenium
Frank Dulong Lead Scientist
Top of Page
Mercury is a potent neurotoxin that impacts ecosystems and ultimately, human health. Under the U.S. EPA Mercury and Air Toxics Standards (MATS), emissions limits for mercury and associated constituents from U.S. coal-fired utilities are being introduced (EPA, 2011a). To assist stakeholders in the U.S. and throughout the world the USGS, provides detailed information on the occurrence and distribution of Hg and other trace elements in... [+]
coal. Combustion-sourced elemental mercury is recognized as global problem due to its long residence time in the atmosphere and resulting global transport. The USGS has unique capabilities to quantify the origin and distribution of mercury in coal, its capture by power plant air pollution controls, or emission and re-distribution of Hg in the environment. These capabilities allow the USGS to help engineers and regulators find workable approaches to mercury reduction
USGS and EPA Coal Databases
While USGS results were not used in developing the U.S. EPA MATS standards, the USGS, through its U.S. and international coal databases and research on trace elements in coal, has much information that is relevant to understanding how Hg in coal occurs and why some coals have more Hg than others. Since the 1980s, the USGS has compiled data on the quality and chemical composition of U.S. coals using samples that represent the entire thickness of a coal bed in the ground. This database, known as COALQUAL, contains data for more than 7,000 U.S. coal samples. Using COALQUAL, a mean mercury concentration of 0.17 parts per million (ppm) was determined for in-ground coal for the entire U.S. (Tewalt et al., 2001). In 1999 and again in 2010, the U.S. EPA compiled data for coal shipments delivered to U.S. power stations. The 2010 data were used in developing the MATS standards (EPA, 2011b, 2011c). These results give a mean Hg concentration of about 0.12 ppm, much less than USGS results for coal in the ground (Fig. 2).
The difference between the USGS and U.S. EPA results is explained by the fact that some coals, especially those high in sulfur, undergo preparation (cleaning) prior to delivery. As one of the benefits of coal cleaning, Hg associated with mineral matter is reduced in many cases and this is reflected in lower average Hg values for the U.S.EPA databases when compared to USGS results. In addition, COALQUAL contains a greater proportion of samples from the U.S. Appalachian Basin which in general, have higher mercury contents than low-sulfur western coals from Powder River Basin (PRB) of Wyoming and Montana. Use of PRB coals has increased markedly in the last two decades, and this trend is reflected in the U.S. EPA databases for delivered coal when compared to values for in-ground coal determined from COALQUAL. Nonetheless, COALQUAL is very useful in showing how U.S. coals differ by location and rank, and in comparing U.S. coal with international samples.
In addition to the USGS COALQUAL database for domestic coal samples, the USGS maintains a small international database known as the World Coal Quality Inventory (WoCQI) which contains 1,580 samples of coal from 57 countries (Tewalt et al., 2010). One of the largest groups of samples in the WoCQI database is for China (328 samples). Excluding 23 samples of cleaned coal, the remaining 305 samples of in-ground Chinese coal, representing 25 provinces and autonomous regions, give a mean mercury content of 0.16 ppm Hg, similar to the average for in-ground U.S. coal in COALQUAL and identical to that determined for China by Dai et al. (2012), using a larger group of 1,666 samples.
Figure 2. Plots of the mercury distribution of U.S. coal compiled in USGS COALQUAL database and U.S. EPA databases from 1999, and 2010 data used to inform the EPA MATS standards (Kolker et al., 2012).
Mercury Mode of Occurrence in Coal
USGS research on U.S. and international coal samples provides information on the amount and forms of mercury and other elements present. USGS studies using various approaches show that pyrite is the primary host of mercury in many bituminous coals, whereas the proportion of mercury present in organic parts of coal is generally greater in low-rank (lignite and sub-bituminous) coal (Kolker et al., 2006; Fig. 3). Many Eastern U.S. bituminous coals are cleaned prior to use in utility power stations, to reduce sulfur emissions. This coal preparation reduces sulfur content, primarily by removing pyrite from coal. In doing so, a portion of the mercury present may also be removed, a co-benefit of sulfur reduction. With introduction of more stringent Hg standards under MATS, various engineering approaches, including addition of flue gas desulphurization (FGD) scrubbers will likely be required. This will also allow higher sulfur coals to be used without cleaning, by capturing sulfur emissions. By understanding the mode of occurrence of mercury in coal, and the concentration of constituents that affect capture of mercury, such as chlorine, the USGS provides information needed to help predict and control mercury emissions.
Figure 3. Plot of mercury in pyrite of a South African coal determined by laser ablation ICP-MS in USGS labs (inset). Mean concentration for more than 250 pyrite analyses is approximately 10 times the mercury content of the whole coal (UNEP, 2014). Data represent individual laser analysis points that are 20 (blue) or 25 (red) micrometers in diameter.
Dai, S., Ren, D., Chou, C.-L., Finkelman, R.B., Seredin, V.V., and Zhou, Y., 2012, Geochemistry of trace elements in Chinese coals: A review of abundances, genetic types, and impacts on human health and industrial utilization: International Journal of Coal Geology, v. 94, p. 3-21.http://dx.doi.org/10.1016/j.coal.2011.02.003
Kolker, A., Senior, C. L., and Quick, J. C., 2006, Mercury in coal and the impact of coal quality on mercury emissions from combustion systems: Applied Geochemistry, v. 21, p. 1821-1836.http://dx.doi.org/10.1016/j.apgeochem.2006.08.001
Kolker, A., Quick, J.C., Senior, C.L., and Belkin, H.E., 2012, Mercury and halogens in coal- Their role in determining mercury emissions from coal combustion: U.S. Geological Survey Fact Sheet 2012-3122, 6 p.http://pubs.er.usgs.gov/publication/fs20123122
Tewalt, S.J., Bragg, L.J., and Finkelman, R.B., 2001, Mercury in U.S. coal- Abundance, distribution, and modes of occurrence: U.S. Geological Survey Fact Sheet FS-095-01, 4 p.http://pubs.er.usgs.gov/publication/fs09501
Tewalt , S. J., Belkin, H.E., SanFilipo, J.R., Merrill, M.D., Palmer, C.A., Warwick, P.D., Karlsen, A.W., Finkelman, R.B., and Park, A.J., 2010, Chemical analyses in the world coal quality inventory, vers. 1: U.S. Geological Survey Open File Report 2010-1196, 4 p. and data files.http://pubs.er.usgs.gov/publication/ofr20101196
UNEP, 2014, Collaborative studies for mercury characterization in coal and coal combustion products, Republic of South Africa, United Nations Environment Programme Project Report prepared by U.S. Geological Survey (USGS), Reston, Virginia, January, 2014, in press.http://www.unep.org/hazardoussubstances
U.S. EPA, 2011a, Mercury and Air Toxics Standards (MATS):http://www.epa.gov/mats/pdfs/20111216MATSfinal.pdf
U.S. EPA, 2011b, Air Toxics Standards for Utilities – MATS ICR Data (EGU_ICR_PartI_and_PartII): Online,http://www.epa.gov/ttn/atw/utility/utilitypg.html, ACCESS data file.
U.S. EPA 2011c, Air Toxics Standards for Utilities – MATS ICR Data (EGU ICR Part III): Online,http://www.epa.gov/ttn/atw/utility/utilitypg.html, ACCESS data file.
Energy resources like coal, oil and natural gas are the pillars of our modern industrial society and they are the major catalyst for the fast paced technological advancement. However, their exploitation has side effects whose magnitude has triggered widespread concerns in the recent years, as the public has become more aware of the concept of global warming or the increasing incidence... [+]
of diseases like cancer or asthma. At the forefront of geomedical research, the USGS has the role to provide the public and the policymakers with the scientific information needed to account for the environmental and human health consequences of energy resource extraction, processing, transportation and use. The USGS is addressing these issues in an interdisciplinary context, through a dedicated project entitled “Impacts of Energy Resources on Human Health and Environmental Quality”. Several research topics include: Balkan Endemic Nephropathy (BEN), “panendemic nephropathy” (i.e., diseases similar to BEN but outside the Balkans), environmental contamination related to mountain top mining (MTM) and coal slurry in the Appalachian Basin and the release of toxic substances in energy combustion products.
Orem W., Tatu C., Pavlovic N., Bunnell J., Kolker A., Engle M. and Ben Stout (2009) Health Effects of Energy Resources. U.S. Geological Survey Fact Sheet 2009-3096.
Kolker A., Engle, M., Stracher G., Hower J., Prakash A., Radke L., ter Schure A., Heffern E (2009) Emissions from coal fires and their impact on the environment: U.S. Geological Survey Fact Sheet 2009-3084.
Orem W.H., Bunnell J.E. Tatu C.A., Pavlovic N., and (2009) Toxicological pathways of relevance to medical geology. In: Encyclopedia of Environmemntal Health (Nriagu J., editor), Elsevier Science 2011.
Contact: William H. Orem email@example.com
Air can be a significant source of all sorts of human health hazards and compared to water and soil, transport of noxious chemicals and particulates or pathogenic microorganisms occurs much faster and can affect populational groups on a larger scale. USGS has been involved in several projects exploring the links between human health and air... [+]
quality alterations due to fossil fuel extraction/mining and combustion.
The presence in air of fine particulate matter 2.5 micrometers in size, called PM2.5, and originating from coal combustion and other sources, is a serious health concern. This material is small enough to be readily lodged in small interstices (alveoli) in the lungs. The U.S. Environmental Protection Agency (USEPA) air-quality regulatory standards are based on limits in the amount of PM2.5, while the USGS can provide more detailed knowledge on the chemistry, mineralogy, surface characteristics and potential toxicity of such particles.
A multi-agency study in the Navajo Nation of New Mexico has focused on the extent of human exposure to contaminants in particulate matter derived from domestic coal combustion and links to respiratory disease. The study was based on both epidemiological data examining the incidence of respiratory diseases as well as on field studies measuring indoor and outdoor air quality, including PM2.5. Air sampling in the Navajo Nation has shown that in winter, when coal stoves are in use, some homes exceed the USEPA 24-hour ambient (outdoor) PM2.5 standard. Analysis of PM2.5 samples from Navajo homes burning coal shows an abundance of organic compounds indicative of a coal source.
Bunnell J. E., Garcia L.V, Furst J.M., Lerch H., Olea R.A., Suitt S.E., and Kolker A. (2010) Navajo coal combustion and respiratory health near shiprock, new Mexico. J Environ Public Health. 2010:260525.
Mercury Contamination in Fish USGS Podcast (Episode 102)
Your browser does not support the audio element.
Download Directly See Podcast Transcript
Coal and Human Health USGS Podcast (Episode 103)
USGS Mercury in the Environment Website
USGS Wisconsin District Mercury Studies Team
Energy Resources Program - Produced Waters
USGS Public Health Website
USGS Health and Environment Fact Sheets
USGS National Research Program (NRP)
USGS Water Program Fact Sheets: Fact Sheet 1 / Fact Sheet 2
USGS Minerals Information Program: Statistics / Production and Uses
USGS Toxics Substances Hydrology Program
USGS Water Resources in California: Detailed Study and Assessment of Irrigation Drainage in the Salton Sea Area, Imperial Valley, California
USGS Acid Mine Drainage Activities
USGS Kansas Water Science Center: Abstract / Fact Sheet
USGS Patuxent Wildlife Research Center: Fact Sheet
USGS New Mexico Water Science Center
USGS Abandoned Mine Land Initiative: Selenium in Animas River linked to Mancos Shale outcrops in this Colorado drainage basin
USGS Data Series 800 Publication: Digital Representation of Oil and Natural Gas Well Pad Scars in Southwest Wyoming
Mobilization of selenium from the Mancos Shale and associated soils in the lower Uncompahgre River Basin, Colorado - Applied Geochemistry Article
Arsenic and Mercury in the Soils of an Industrial City in the Donets Basin, Ukraine [28MB] [pdf]
National Atmospheric Deposition Program - Mercury Deposition Network
U.S. EPA Clean Air Interstate Rule
U.S. EPA Clean Air Mercury Rule
Agency for Toxic Substances and Disease Registry (ASTDR)
U.S. Department of the Interior - National Irrigation Water Quality Program
National Water Quality Assessment Program (NAQWA) - National Analysis of Trace Elements Project
United Nations Environment Programme (UNEP)
U.S. EPA, 2011a, Mercury and Air Toxics Standards (MATS) Rule
U.S. EPA Technology Transfer Network - Air Toxics Web Site: 2011b, Air Toxics Standards for Utilities – MATS ICR Data (EGU_ICR_PartI_and_PartII): [Online, ACCESS data file]
U.S. EPA Technology Transfer Network - Air Toxics Web Site: 2011c, Air Toxics Standards for Utilities – MATS ICR Data (EGU ICR Part III): [Online, ACCESS data file]
Wyoming State Geological Survey - Selected Bibliography on selenium
Lawrence Berkely Laboratory: X-ray absorption spectroscopy and x-ray fluorescence microprobe mapping to analyze redistribution of selenium in contaminated soil samples
Web Elements: The Periodic Table on the Web - Selenium
National Center for Health Statistics
International Medical Geology Association
Acid Drainage Technology Initiative
American Society of Mining and Reclamation
Office of Surface Mining
Page Last Modified: Monday, August 31, 2015