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USGS2005

Characterization and modes of occurrence of elements in feed coal and coal combustion products from a power plant utilizing low-sulfur coal from the Powder River Basin, Wyoming

The U.S. Geological Survey and the University of Kentucky Center for Applied Energy Research are collaborating with an Indiana utility company to determine the physical and chemical properties of feed coal and coal combustion products from a coal-fired power plant. The Indiana power plant utilizes a low-sulfur (0.23 to 0.47 weight percent S) and lowash (4.9 to 6.3 weight percent ash) subbituminous coal from the Wyodak-Anderson coal zone in the Tongue River Member of the Paleocene Fort Union Formation, Powder River Basin, Wyoming. Based on scanning electron microscope and X-ray diffraction analyses of feed coal samples, two mineral suites were identified: (1) a primary or detrital suite consisting of quartz (including beta-form grains), biotite, feldspar, and minor zircon; and (2) a secondary authigenic mineral suite containing alumino-phosphates (crandallite and gorceixite), kaolinite, carbonates (calcite and dolomite), quartz, anatase, barite, and pyrite. The primary mineral suite is interpreted, in part, to be of volcanic origin, whereas the authigenic mineral suite is interpreted, in part, to be the result of the alteration of the volcanic minerals. The mineral suites have contributed to the higher amounts of barium, calcium, magnesium, phosphorus, sodium, strontium, and titanium in the Powder River Basin feed coals in comparison to eastern coals. X-ray diffraction analysis indicates that (1) fly ash is mostly aluminate glass, perovskite, lime, gehlenite, quartz, and phosphates with minor amounts of periclase, anhydrite, hematite, and spinel group minerals; and (2) bottom ash is predominantly quartz, plagioclase (albite and anorthite), pyroxene (augite and fassaite), rhodonite, and akermanite, and spinel group minerals. Microprobe and scanning electron microscope analyses of fly ash samples revealed quartz, zircon, and monazite, euhedral laths of corundum with merrillite, hematite, dendritic spinels/ferrites, wollastonite, and periclase. The abundant calcium and magnesium mineral phases in the fly ash are attributed to the presence of carbonate, clay, and phosphate minerals in the feed coal and their alteration to new phases during combustion. The amorphous diffraction-scattering maxima or glass 'hump' appears to reflect differences in chemical composition of fly ash and bottom ash glasses. In Wyodak-Anderson fly and bottom ashes, the center point of scattering maxima is due to calcium and magnesium content, whereas the glass 'hump' of eastern fly ash reflects variation in aluminum content. The calcium- and magnesium-rich and alumino-phosphate mineral phases in the coal combustion products can be attributed to volcanic minerals deposited in peat-forming mires. Dissolution and alteration of these detrital volcanic minerals occurred either in the peat-forming stage or during coalification and diagenesis, resulting in the authigenic mineral suite. The presence of free lime (CaO) in fly ash produced from Wyodak-Anderson coal acts as a self-contained 'scrubber' for SO3, where CaO + SO3 form anhydrite either during combustion or in the upper parts of the boiler. Considering the high lime content in the fly ash and the resulting hydration reactions after its contact with water, there is little evidence that major amounts of leachable metals are mobilized in the disposal or utilization of this fly ash.

Scientific Investigations Report↗

USGS2013

Changing patterns in the use, recycling, and material substitution of mercury in the United States

Environmental concerns have led to numerous regulations that have dramatically decreased the reported production and use of mercury in the United States since the 1980s. Government legislation and subsequent industry actions have led to increased collection of mercury-containing materials and the recovery of mercury through recycling. Mercury emissions have been reduced and effective alternatives to mercury products have been developed for many applications. This study updates and quantifies the changes in demand, supply, use, and material flow for mercury in various sectors in the United States that have taken place since 1996. Nearly all primary mercury produced in the United States is derived as a byproduct of processing of gold and silver ore in Nevada. Since 2001, annual production of mercury from gold and silver mining in Nevada has decreased by 22 percent overall because ore from greater depths containing low grade mercury is recovered, and mercury emissions from this source have decreased by 95 percent as a result of increased regulation and improved collection and suppression technology. The distribution of consumption of mercury in the United States has changed as a result of regulation (elimination of large-scale mercury use in the paint and battery sectors), reduction by consumers (decommissioning of mercury-cell chloralkali manufacturing capacity), and technological advances (improvements in dental, lighting, and wiring sectors). Mercury use in the chloralkali sector, the leading end-use sector in the United States in 1996, has declined by 98 percent from 136 metric tons (t) in 1996 to about 0.3 t in 2010 because of increased processing and recycling efficiencies and plant closures or conversion to other technologies. As plants were closed, mercury recovered from the infrastructure of decommissioned plants has been exported, making the United States a net exporter of mercury, even though no mercury has been produced as the primary product from mines in the United States since 1992. In 1996, the three leading end-use sectors for mercury in the United States were chloralkali manufacturing (accounting for 38 percent of consumption), electrical and electronic instrumentation (13 percent of consumption), and instruments and measuring devices (11 percent of consumption). In 2010, the three leading end-use sectors were dental amalgam (accounting for between 35 and 57 percent of consumption), electrical and electronic instrumentation (29 percent of consumption), and batteries (8 percent of consumption). Mercury use in lighting is increasing because incandescent lights are being phased out in favor of mercury-containing compact fluorescent bulbs, but the demand for mercury per unit produced is small. Dental amalgam constituted the largest amount of mercury in use in the United States. One study reported about 290 t of mercury in dental amalgam was estimated to be contained in human mouths, an estimated 30 t of mercury amalgam was treated as waste, 28.5 t of mercury amalgam was released to the environment, 6 t of amalgam was recycled, and 3.5 t was treated and stored in landfills in 2009. Mercury contained in products recovered by State, municipal, or industry collection activities is recycled, but the estimated overall recycling rate is less than 10 percent. Increasingly, the U.S. mercury recycling industry has been processing a significant amount of mercury-containing material derived from foreign gold mining operations or decommissioned mercury-cell chloralkali plants. Regulation of mercury export and storage is expected to result in surplus mercury inventories in the United States. The Mercury Export Ban Act of 2008 limits elemental mercury exports for unregulated uses such as artisanal gold mining after January 1, 2013, and requires development of adequate long-term storage facilities in the United States for elemental mercury. During the past 4 years, producers and recyclers of elemental mercury have been exporting large quantities of mercury in anticipation of this regulation, but the U.S. inventory of mercury in 2010 was estimated to have exceeded 7,000 t from Government stockpiles and industry stocks. Costs attributed to long-term storage may affect the competitiveness of mercury recycling.

Scientific Investigations Report↗

USGS2018

Geochemical conditions and nitrogen transport in nearshore groundwater and the subterranean estuary at a Cape Cod embayment, East Falmouth, Massachusetts, 2013–14

Nitrogen transport and transformation were studied during 2013 to 2014 by the U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency, in a subterranean estuary beneath onshore locations on the Seacoast Shores peninsula, a residential area in Falmouth, Massachusetts, served by septic systems and cesspools, and adjacent offshore locations in the Eel River, a saltwater embayment connected to the ocean. The field investigation included installation and sampling of clusters of wells and temporary sampling points near a transect extending from about 35 meters (m) onshore to 18 m offshore. The fresh groundwater at the study site formed a lens about 11 m thick at the shoreline that was underlain by saline groundwater. Groundwater flow in the water-table aquifer was oriented northwestward toward the embayment. Nitrate concentrations in the fresh groundwater at a site about 35 m onshore increased in the downward direction from less than 500 micromoles per liter near the water table to about 1,700 micromoles per liter just above the freshwater/saltwater transition zone. Dissolved oxygen was largely absent in the onshore fresh groundwater. Distributions of salinity, dissolved oxygen, and nitrate at the shoreline and offshore generally were similar to those onshore; at some locations, however, shallow saline water was present above the freshwater, and there were scattered occurrences of elevated dissolved oxygen concentrations. Geochemical indicators of nitrate reduction, including concentrations of the reaction product nitrogen gas, stable isotope ratios of nitrate and nitrogen gas, and changes in alkalinity, provided evidence for nitrate reduction in two zones separated vertically by a zone 7–8 m thick with no evidence of nitrate reduction. The shallow nitrate-reduction zone was near the water table in fresh groundwater onshore, where nitrate reduction may be related to particular recharge conditions at nearby sources. The shallow nitrate-reduction zone also may be related to an interval of fine-grained sediments at about the same altitude (−1 to −6 m relative to the National Geodetic Vertical Datum of 1929), where flow is slower and reactive electron donors such as solid organic carbon, iron, or sulfide phases may be present to drive the reduction. The deep nitrate-reduction zone was near the freshwater/saltwater transition zone, where nitrate reduction may be related to mixing of freshwater containing nitrate and saltwater containing dissolved organic carbon and ammonium, or to fine-grained sediments near the transition zone. The maximum amount of nitrate converted to nitrogen gas was estimated to be less than or equal to 300 micromoles per liter in both nitrate-reduction zones. The presence of nitrate and low dissolved oxygen concentrations in the 7–8-meter-thick zone between the shallow and deep nitrate-reduction zones are conditions that could permit nitrate reduction. The absence of evidence of nitrate reduction in the high-nitrate zone may have resulted from the lack of reactive electron donors in that depth interval. The high-nitrate zone dissipated somewhat in the offshore direction, but the current study did not extend far enough to encompass the fresh groundwater discharge area or determine how much of the nitrate was removed prior to discharge. A shallow intertidal saltwater cell was formed during a spring tide by saltwater infiltration during tidal run-up on the beach. Nitrate reduction might have occurred if nitrate-containing fresh groundwater discharging to the estuary mixed with the saltwater containing dissolved organic carbon in this zone, but samples collected from the intertidal saltwater cell during this study were not analyzed for indicators of nitrate reduction. Elevated dissolved oxygen concentrations in fresh groundwater 9 m offshore may indicate that groundwater flow was partly oblique to the sampling transect or that groundwater from a regional flow system was converging under the river near the study area. Flow directions also may have been affected by aquifer heterogeneity such as the shallow fine-grained sediments onshore and at the bottom of the Eel River. Improved understanding of the fate of nitrate in this type of complex setting might be gained by including additional characterization of aquifer heterogeneity and groundwater flow and extending investigations of nitrate reduction to the shallow sediments in the intertidal saltwater cell and adjacent subtidal zone and to locations farther offshore beneath the estuary.

Massachusetts↗

USGS2015

Field Manual of Wildlife Diseases

Welcome to a new version of the “Field Manual of Wildlife Diseases.” Unlike the previous printed versions of this publication, this new version is being developed as a “living“ electronic publication. Content will periodically be added and (or) updated as warranted, and it will always be reviewed by scientific experts (“peer reviewed”) before it is released. Thus, this publication will never be completed, and readers should download revised versions of specific chapters, glossaries, and the appendixes whenever they visit the publication Web site. The purpose of this manual is to provide information that will enhance the ecological understanding and comfort level of nonspecialists so that they can address various aspects of wildlife disease within the context of wildlife conservation and management. Other readers, from students to science professionals, may also find the information presented to be of interest and value. Constructive suggestions from readers will help guide adjustments as this project progresses. We begin this new manual with introductory contextual and historical background about the convergence of wildlife disease with wildlife management as a wildlife conservation concern (section A, chap. 1). The remainder of the publication is focused on pragmatic information and considerations for addressing various aspects of wildlife disease. Section B focuses on concepts associated with disease surveillance and response to outbreaks, and section C deals with specific techniques for disease surveillance and investigation. Section D, “Diseases of Wild Birds,” and others that follow will address diseases of concern in various species groups. Electronic links facilitate timely access to a wide variety of supplemental information and processes relevant to content in this new version of the “Field Manual of Wildlife Diseases.”

Techniques and Methods↗

USGS2006

Water-resources data for the United States: water year 2006

Water resources data are published annually for use by engineers, scientists, managers, educators, and the general public. These archival products supplement direct access to current and historical water data provided by NWISWeb. Beginning with Water Year 2006, annual water data reports are available as individual electronic Site Data Sheets for the entire Nation for retrieval, download, and localized printing on demand. National distribution includes tabular and map interfaces for search, query, display and download of data. From 1962 until 2005, reports were published by State as paper documents, although most reports since the mid-1990s are also available in electronic form through this web page. Reports prior to 1962 were published in occasional USGS Water-Supply Papers and other reports.

Water Data Report↗

USGS2007

Water-resources data for the United States: water year 2007

Water Data Report↗

USGS2009

Water-resources data for the United States: Water year 2009

Water Data Report↗

USGS2010

Water-resources data for the United States: Water year 2010

Water Data Report↗

USGS2012

Water-resources data for the United States: water year 2012

Water Data Report↗

USGS2023

A novel non-destructive workflow for examining germanium and co-substituents in ZnS

A suite of complementary techniques was used to examine germanium (Ge), a byproduct critical element, and co-substituent trace elements in ZnS and mine wastes from four mineral districts where germanium is, or has been, produced within the United States. This contribution establishes a comprehensive workflow for characterizing Ge and other trace elements, which captures the full heterogeneity of samples through extensive pre-characterization. This process proceeded from optical microscopy, to scanning electron microscopy and cathodoluminescence (CL) imaging, to electron microprobe analysis, prior to synchrotron-based investigations. Utilizing non-destructive techniques enabled reanalysis, which proved essential for verifying observations and validating unexpected results. In cases where the Fe content was <0.3 wt% in ZnS, cathodoluminescence imaging proved to be an efficient means to qualitatively identify trace element zonation that could then be further explored by other micro-focused techniques. Micro-focused X-ray diffraction was used to map the distribution of the non-cubic ZnS polymorph, whereas micro-focused X-ray fluorescence (μ-XRF) phase mapping distinguished between Ge 4+ hosted in primary ZnS and a weathering product, hemimorphite [Zn 4 Si 2 O 7 (OH) 2 ·H 2 O]. Microprobe data and μ-XRF maps identified spatial relationships among trace elements in ZnS and implied substitutional mechanisms, which were further explored using Ge and copper (Cu) X-ray absorption near-edge spectroscopy (XANES). Both oxidation states of Ge (4+ and 2+) were identified in ZnS along with, almost exclusively, monovalent Cu. However, the relative abundance of Ge oxidation states varied among mineral districts and, sometimes, within samples. Further, bulk XANES measurements typically agreed with micro-focused XANES (μ-XANES) spectra, but unique micro-environments were detected, highlighting the importance of complementary bulk and micro-focused measurements. Some Ge μ-XANES utilized a high energy resolution fluorescence detector, which improved spectral resolution and spectral signal-to-noise ratio. This detector opens new opportunities for exploring byproduct critical elements in complex matrices. Overall, the non-destructive workflow employed here can be extended to other byproduct critical elements to more fully understand fundamental ore enrichment processes, which have practical implications for critical element exploration, resource quantification, and extraction.

Frontiers in Earth Science↗

USGS2009

The weathering of a sulfide orebody: Speciation and fate of some potential contaminants

Various potentially toxic trace elements such as As, Cu, Pb and Zn have been remobilized by the weathering of a sulfide orebody that was only partially mined at Leona Heights, California. As a result, this body has both natural and anthropogeni- cally modified weathering profiles only 500 m apart. The orebody is located in a heavily urbanized area in suburban Oakland, and directly affects water quality in at least one stream by producing acidic conditions and relatively high concentrations of dissolved elements (e.g., ??500 ??g/L Cu, ??3700 ??g/L Zn). Micrometric-scale mineralogical investigations were performed on the authigenic metal-bearing phases (less than 10 ??m in size) using electron-probe micro-analysis (EPMA), micro-Raman, micro X-ray absorption spectroscopy (??XAS), scanning X-ray diffraction ((??SXRD) and scanning X-ray fluorescence (??-SXRF) mapping techniques. Those measurements were coupled with classical mineralogical laboratory techniques, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Authigenic metal-bearing phases identified are mainly sulfates (jarosite, epsomite, schwertmannite), Fe (oxy-)hydroxides (goethite, hematite and poorly crystalline Fe products) and poorly crystalline Mn (hydr-)oxides. Sulfates and Fe (oxy-)hydroxides are the two main secondary products at both sites, whereas Mn (hydr-) oxides were only observed in the samples from the non-mining site. In these samples, the various trace elements show different affinities for Fe or Mn compounds. Lead is preferentially associated with Mn (hydr-)oxides and As with Fe (oxy-)hydroxides or sulfates. Copper association with Mn and Fe phases is questionable, and the results obtained rather indicate that Cu is present as individual Cu-rich grains (Cu hydroxides). Some ochreous precipitates were found at both sites and correspond to a mixture of schwertmannite, goethite and jarosite containing some potentially toxic trace elements such as Cu, Pb and Zn. According to the trace element distribution and relative abundance of the unweathered sulfides, this orebody still represents a significant reservoir of potential contaminants for the watershed, especially at the non-mining site, as a much greater proportion of sulfides is left to react and because of the lower porosity at this site.

Canadian Mineralogist↗

USGS2012

Using mark-recapture models to estimate survival from telemetry data: Chapter 9.2

Analyzing telemetry data within a mark–recapture framework is a powerful approach for estimating demographic parameters (e.g., survival and movement probabilities) that might otherwise be difficult to measure. Yet many studies using telemetry techniques focus on fish behavior and fail to recognize the potential of telemetry data to provide information about fish survival. The sophistication of both mark–recapture modeling and telemetry has dramatically improved since the 1980s, largely due to technological advancements in computing power (for mark–recapture models) and electronic components (for telemetry). Such advances now allow mark–recapture models to take advantage of the detailed information that telemetry techniques can provide. The key feature of mark–recapture models is simultaneous estimation of detection and survival probabilities. With telemetry, a “capture” event consists of detecting a given tag code one or more times at a specific location or time. By contrast, in some studies interest may focus on the probability of detecting a single tag transmission (see Sections 7.2 and 9.1). Compared to conventional mark and recapture methods, telemetry methods often have greater detection probabilities due to large detection ranges, increased “effort” (i.e., continuous monitoring with autonomous receivers), and ability to simultaneously monitor multiple locations. Nonetheless, perfect detectability is rare in telemetry studies because both random (e.g., from electronic noise) and nonrandom processes (e.g., receiver loses power temporarily) can allow a fish to pass a receiver undetected. Failure to account for imperfect detection can lead to serious bias in survival estimates. When using telemetry to estimate survival, it is therefore critical to explicitly estimate detection probabilities to ensure unbiased estimates of survival (see Section 7.2). Fortunately, using telemetry techniques and mark–recapture models together yields the best of both worlds: Well-designed telemetry systems deliver high detection probabilities that result in precise estimates from small sample sizes. Mark–recapture models ensure estimates of the demographic parameters are unbiased with respect to the detection process.

Book chapter↗

USGS1988

Morphology of glochidia of Lampsilis higginsi (Bivalvia: Unionidae) compared with three related species

Glochidia of the endangered unionid mussel Lampsilis higginsi (Lea) are morphologically similar to those of several other species in the upper Mississippi River. Life history details, such as the timing of reproduction and identity of host fish, can be readily studied if the glochidia of L. higginsi can be distinguished from those of related species. Authors used light and scanning electron microscopy and statistical analyses of three shell measurements, shell length, shell height, and hinge length, to compare the glochidia of L. higginsi with those of L. radiata siliquoidea (Barnes), L. ventricosa (Barnes), and Ligumia recta (Lamarck). Glochidia of L. higginsi were differentiated by scanning electron microscopy on the basis of a combined examination of the position of the hinge ligament and the width of dorsal ridges, but were indistinguishable by light microscope examination or by statistical analyses of measurements.

American Malacological Bulletin↗

USGS2010

Geographic variation in the plumage coloration of willow flycatchers Empidonax traillii

The ability to identify distinct taxonomic groups of birds (species, subspecies, geographic races) can advance ecological research efforts by determining connectivity between the non-breeding and breeding grounds for migrant species, identifying the origin of migrants, and helping to refine boundaries between subspecies or geographic races. Multiple methods are available to identify taxonomic groups (e.g., morphology, genetics), and one that has played an important role for avian taxonomists over the years is plumage coloration. With the advent of electronic devices that can quickly and accurately quantify plumage coloration, the potential of using coloration as an identifier for distinct taxonomic groups, even when differences are subtle, becomes possible. In this study, we evaluated the degree to which plumage coloration differs among the four subspecies of the willow flycatcher Empidonax traillii, evaluated sources of variation, and considered the utility of plumage coloration to assign subspecies membership for individuals of unknown origin. We used a colorimeter to measure plumage coloration of 374 adult willow flycatchers from 29 locations across their breeding range in 2004 and 2005. We found strong statistical differences among the mean plumage coloration values of the four subspecies; however, while individuals tended to group around their respective subspecies' mean color value, the dispersion of individuals around such means overlapped. Mean color values for each breeding site of the three western subspecies clustered together, but the eastern subspecies' color values were dispersed among the other subspecies, rather than distinctly clustered. Additionally, sites along boundaries showed evidence of intergradation and intermediate coloration patterns. We evaluated the predictive power of colorimeter measurements on flycatchers by constructing a canonical discriminant model to predict subspecies origin of migrants passing through the southwestern U.S. Considering only western subspecies, we found that individuals can be assigned with reasonable certainty. Applying the model to migrants sampled along the Colorado River in Mexico and the U.S. suggests different migration patterns for the three western subspecies. We believe that the use of plumage coloration, as measured by electronic devices, can provide a powerful tool to look at ecological questions in a wide range of avian species.

Journal of Avian Biology↗

USGS1984

ORIGIN OF QUARTZ IN COAL.

Both a scanning electron microscope and an electron microprobe (EMP) were used in this study to analyze the cathodoluminescence properties of quartz grains in samples of the Upper Freeport coal bed because quartz grains in coal are small (silt sized) and below the resolution capabilities of a standard luminoscope. Quartz grains were identified by the detection of silicon alone with energy dispersive X-ray units attached to both the SEM and the EMP.

Conference Paper↗

USGS1985

Managing mapping data using commercial data base management software.

Electronic computers are involved in almost every aspect of the map making process. This involvement has become so thorough that it is practically impossible to find a recently developed process or device in the mapping field which does not employ digital processing in some form or another. This trend, which has been evolving over two decades, is accelerated by the significant improvements in capility, reliability, and cost-effectiveness of electronic devices. Computerized mapping processes and devices share a common need for machine readable data. Integrating groups of these components into automated mapping systems requires careful planning for data flow amongst them. Exploring the utility of commercial data base management software to assist in this task is the subject of this paper. -Author

Photogrammetric Engineering and Remote Sensing↗

USGS1985

DISTRIBUTION OF TRACE ELEMENTS IN COAL MINERALS OF SELECTED EASTERN UNITED STATES COALS.

The association of 34 elements with minerals found in coal was determined by a combination of analytical techniques on size and density fractions of low-temperature ash (LTA). Instrumental neutron activation analysis was used to determine the concentrations of the elements, and X-ray diffraction analysis, scanning electron microscopy, and scanning transmission electron microscopy were used to identify the minerals present in the LTA. The distribution of elemental and mineral concentrations in different size fractions was also determined. Between 35 and 60 weight percent of the LTA was composed of particles smaller than 2 mu m.

Conference Paper↗

USGS1985

Elemental X-ray mapping of agglutinated foraminifer tests: A non- destructive technique for determining compositional characteristics.

The composition of agglutinated foraminiferal tests vary remarkably in response to local substrate characteristics, physiochemical properties of the water column and species- dependant selectivity of test components. We have employed a technique that combines a scanning electron microscope with an energy dispersive X-ray spectrometer system to identify major and minor elemental constituents of agglutinated foraminiferal walls. As a sample is bombarded with a beam of high energy electrons, X-rays are generated that are characteristic of the elements present. As a result, X- ray density maps can be produced for each of several elements present in the tests of agglutinated foraminifers.

Micropaleontology↗