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Evaluation of stream capture related to groundwater pumping, middle Humboldt River Basin, Nevada

Historical, future, and potential stream capture from groundwater pumping in the middle Humboldt River Basin (MHRB), Nevada, is estimated using a calibrated numerical groundwater flow model. The model was developed to estimate (1) stream capture, which is the change in flux between the groundwater system and the Humboldt River and tributaries, and (2) change in streamflow, which is the change in streamflow estimated for the Imlay gage on the Humboldt River (U.S. Geological Survey streamgage 10333000). Historical stream capture for water years (WYs) 1961–2015 is estimated using recorded and estimated groundwater pumping during that period. Future (predictive) stream capture was based on historical stresses (WYs 1961–2015) using a scenario that simulated non-mine pumping from WY 2015 at a uniform rate for 100 years into the future. Potential stream capture throughout the middle Humboldt River Basin from groundwater pumping during varying durations of time are presented in a series of capture maps. Maps also are presented that show the potential to capture from groundwater evapotranspiration, as well as the storage changes for pumping duration of 100 years. Estimates of historical stream capture from the mainstem Humboldt River during the early 1960s are less than 400 acre-feet per year (acre-ft/yr) when groundwater withdrawals and pumping rates were relatively small compared to more recent times. In the late 1980s and early 1990s, groundwater withdrawals increased and estimated historical stream capture also increased from about 4,000 acre-ft/yr in the late 1980s and early 1990s to as much as 18,800 acre-feet (acre-ft) in WY 1998. In WY 2015, estimated historical stream capture declined to about 13,000 acre-ft because of decreasing groundwater withdrawals and lower streamflow during the drought of WYs 2012–15, resulting in less stream water available for capture. Stream capture was estimated for 100 years into the future based on WY 2015 non-mine pumping rates and mine-dewatering activity through WY 2015. Stream capture is forecast to increase to about 23,000 acre-ft/yr, and streamflow in the Humboldt River could decrease by as much as 19,000 acre-ft/yr. Pumping for mine-dewatering and the associated discharge of that water affects streamflow in the Humboldt River at Imlay, Nevada (U.S. Geological Survey streamgage 10333000). Historically, from WYs 1991 to 2015, streamflow was greater at Imlay gage during active mine-dewatering from mine-water discharge operations and increased by as much as 105,000 acre-ft in WY 1998. The increase was attributed mostly to the discharge of groundwater from mine-related dewatering operations directly into the mainstem Humboldt River or its tributaries, with some of this increase associated with return flows from discharge to rapid infiltration basins. Results indicate that streamflow at Imlay gage is expected to decrease by as much as 1,600 acre-ft/yr 30 years after mine-related pumping and discharge are discontinued. The streamflow reductions at the Imlay gage are expected to then decrease to around 500 acre-ft/yr, 100 years after mine-related pumping and discharge are discontinued. Potential capture maps were produced for pumping durations of 10, 25, 50, and 100 years. Capture map results indicate that areas of greater potential stream capture occur adjacent to the Humboldt River and for upstream tributaries areas north of the Humboldt River.

Nevada↗

Assessment of water resources in lead-zinc mined areas in Cherokee County, Kansas, and adjacent areas

A study was conducted to evaluate water-resources problems related to abandoned lead and zinc mines in Cherokee County, Kansas, and adjacent areas in Missouri and Oklahoma. Past mining activities have caused changes in the hydrogeology of the area. Lead and zinc mining has caused discontinuities and perforations in the confining shale west of the Pennsylvanian-Mississippian geologic contact (referred to as the western area), which have created artificial ground-water recharge and discharge areas. Recharge to the shallow aquifer (rocks of Mississippian age) through collapses, shafts, and drill holes in the shale has caused the formation of a groundwater "mound" in the vicinity of the Picher Field in Kansas and Oklahoma. Discharge of mine-contaminated ground water to Tar Creek occurs in'Oklahoma from drill holes and shafts where the potentiometric surface of the shallow aquifer is above the land surface. Mining of ore in the shallow aquifer has resulted in extensive fracturing and removal of material, which has created highly transmissive zones and voids and increased ground-water storage properties of the aquifer. In the area east of the Pennsylvanian-Mississippian geologic contact (referred to as the eastern area), fractured rock and tailings on the land surface increased the amount of water available for infiltration to the shallow aquifer; in the western area, tailings on the impermeable shale created artificial, perched aquifer systems that slowly drain to surface streams. Pumping of the deep aquifer (rocks of Cambrian and Ordovician age) by towns and industries, which developed as a result of the mining industry, has resulted in a potential for downward movement of water from the shallow aquifer. The potential is greatest in Ottawa County, Oklahoma. Because of the large volume of water that may be transported from the shallow to the deep aquifer, open drill holes or casings present the greatest contamination hazard to water supplies in the deep aquifer. Mining allowed oxidation of ore deposits which, on saturation with water, resulted in poor-quality water that generally contains large concentrations of sulfate and trace metals. Water from mines in the eastern area contained dissolved-solids concentrations of less than 500 mg/L (milligrams per liter), a median pH of 3.9, sulfate concentrations that ranged between 98 and 290 mg/L, and median concentrations for zinc of 37,600 pg/L (micrograms per liter), for lead of 240 pg/L, for cadmium of 180 ug/L, for iron of 70 pg/L, for manganese of 240 pg/L, and for silica of 15 mg/L. Water from mines in the western area contained dissolved-solids concentrations of generally more than 500 mg/L, a median pH of 6.8, sulfate concentrations that ranged between 170 and 2,150 mg/L, and median concentrations for zinc of 3,200 pg/L, for lead of 0 pg/L (minimum detection limit is 10 pg/L), for cadmium of 6 pg/L, for iron of 840 pg/L, for manganese of 440 ug/L, and for silica of 11 mg/L. No conclusive evidence of lateral migration of water from the mines into domestic well-water supplies in the shallow aquifer was found in the study area in Kansas. Analyses of water from public-supply wells tapping the deep aquifer did not indicate contamination with trace metals, although chemical analyses from four of six wells exhibited increasing trends through time in sulfate concentrations. These increases probably reflect localized leakage of water from the shallow aquifer along corroded or leaky well casings. Effects of abandoned lead and zinc mines on tributaries of the Spring River in the eastern area are most severe in Short Creek. Compared with water samples from three other major streams in the eastern area, a sample collected from Short Creek, 2 miles west of Galena, Kansas, during August 1981, contained the largest concentrations of dissolved sulfate (240 mg/L), zinc (25,000 pg/L), cadmium (170 pg/L), manganese (1,700 ug/L), and the lowest pH (6.0). Concentrations of these constituents are due primarily to inflow of ground water from the breccia, mines, and to seepage from chat piles in the Short Creek basin. The largest concentrations of zinc and manganese in the Spring River during August 1981, were observed in analyses of samples collected below Short Creek. In the western area, drainage from tailings, which act as perched aquifers on the impervious Pennsylvanian shales, appeared to have little effect on water quality in Willow Creek during low-flow conditions but caused larger concentrations of dissolved zinc just after a wet period during June 1981. Drainage from tailings cause large concentrations of sulfate, zinc, and cadmium in Tar Creek in Kansas. Compared with four other major streams in the western area in Kansas, Tar Creek contained the largest low-flow concentrations of sulfate (910 mg/L), zinc (5,800 pg/L), and cadmium (40ug/L).

Kansas, Missouri, Oklahoma↗

Concentrations of selected metals in Quaternary-age fluvial deposits along the lower Cheyenne and middle Belle Fourche Rivers, western South Dakota, 2009-10

The headwaters of the Cheyenne and Belle Fourche Rivers drain the Black Hills of South Dakota and Wyoming, an area that has been affected by mining and ore-milling operations since the discovery of gold in 1875. A tributary to the Belle Fourche River is Whitewood Creek, which drains the area of the Homestake Mine, a gold mine that operated from 1876 to 2001. Tailings discharged into Whitewood Creek contained arsenopyrite, an arsenic-rich variety of pyrite associated with gold ore, and mercury used as an amalgam during the gold-extraction process. Approximately 18 percent of the tailings that were discharged remain in fluvial deposits on the flood plain along Whitewood Creek, and approximately 25 percent remain in fluvial deposits on the flood plain along the Belle Fourche River, downstream from Whitewood Creek. In 1983, a 29-kilometer (18-mile) reach of Whitewood Creek and the adjacent flood plain was included in the U.S. Environmental Protection Agency's National Priority List of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980, commonly referred to as a "Superfund site." Listing of this reach of Whitewood Creek was primarily in response to arsenic toxicity of fluvial deposits on the flood plain. Lands along the lower Cheyenne River were transferred to adjoining States and Tribes in response to the Water Resources Development Act (WRDA) of 1999. An amendment in 2000 to WRDA required a study of sediment contamination of the Cheyenne River. In response to the WRDA amendment, the U.S. Geological Survey completed field sampling of reference sites (not affected by mine-tailing disposal) along the lower Belle Fourche and lower Cheyenne Rivers. Reference sites were located on stream terraces that were elevated well above historical stream stages to ensure no contamination from historical mining activity. Sampling of potentially contaminated sites was performed on transects of the active flood plain and adjacent terraces that could potentially be inundated during high-flow events. Sampling began in 2009 and was completed in 2010. A total of 74 geochemical samples were collected from fluvial deposits at reference sites, and 473 samples were collected from potentially contaminated sites. Sediment samples collected were analyzed for 23 metals, including arsenic and mercury. Sequential replicate, split duplicate, and field quality-control samples were analyzed for quality assurance of data-collection methods. The metal concentrations in sediment samples and location information are presented in this report in electronic format (Microsoft Excel), along with non-parametric summary statistics of those data. Cross-sectional topography is graphed with arsenic and mercury concentrations on transects at the potentially contaminated sites. The mean arsenic concentration in reference sediment samples was 8 milligrams per kilogram (mg/kg), compared to 250, 650, and 76 mg/kg for potentially contaminated sediment samples at the surface of the middle Belle Fourche River site, the subsurface of the middle Belle Fourche River site, and the surface of the lower Cheyenne River site, respectively. The mean mercury concentration in reference sediment samples was 16 micrograms per kilogram (μg/kg), compared to 130, 370, and 71 μg/kg for potentially contaminated sediment samples at the surface of the middle Belle Fourche River site, the subsurface of the middle Belle Fourche River site, and the surface of the lower Cheyenne River site, respectively.

South Dakota↗

Assessment of water resources in lead-zinc mined areas in Cherokee County, Kansas, and adjacent areas

A study was conducted to evaluate water-resources problems related to abandoned lead and zinc mines in Cherokee County, Kansas, and adjacent areas in Missouri and Oklahoma. Past mining activities have caused changes in the hydrogeology of the area. Lead and zinc mining has caused discontinuities and perforations in the confining shale west of the Pennsylvanian-Mississippian geologic contact (referred to as the western area), which have created artificial ground-water recharge and discharge areas. Recharge to the shallow aquifer (rocks of Mississippian age) through collapses, shafts, and drill holes in the shale has caused the formation of a ground-water 'mound' in the vicinity of the Picher Field in Kansas and Oklahoma. Discharge of mine-contaminated ground water to Tar Creek occurs in Oklahoma from drill holes and shafts where the potentiometric surface of the shallow aquifer is above the land surface. Mining of ore in the shallow aquifer has resulted in extensive fracturing and removal of material, which has created highly transmissive zones and voids and increased ground-water storage properties of the aquifer. In the area east of the Pennsylvanian-Mississippian geologic contact (referred to as the eastern area), fractured rock and tailings on the land surface increased the amount of water available for infiltration to the shallow aquifer; in the western area, tailings on the impermeable shale created artificial, perched aquifer systems that slowly drain to surface streams. Pumping of the deep aquifer (rocks of Cambrian and Ordovician age) by towns and industries, which developed as a result of the mining industry, has resulted in a potential for downward movement of water from the shallow aquifer. The potential is greatest in Ottawa County, Oklahoma. Because of the large volume of water that may be transported from the shallow to the deep aquifer, open drill holes or casings present the greatest contamination hazard to water supplies in the deep aquifer. Mining allowed oxidation of ore deposits which, on saturation with water, resulted in poor-quality water that generally contains large concentrations of sulfate and trace metals. Water from mines in the eastern area contained dissolved-solids concentrations of less than 500 mg/L (milligrams per liter), a median pH of 3.9, sulfate concentrations that ranged between 98 and 290 mg/L, and median concentrations for zinc of 37,600 micrograms/L (micrograms per liter), for lead of 240 micrograms/L, for cadmium of 180 micrograms/L, for iron of 70 micrograms/L, for manganese of 240 micrograms/L, and for silica of 15 mg/L. Water from mines in the western area contained dissolved-solids concentrations of generally more than 500 mg/L, a median pH of 6.8, sulfate concentrations that ranged between 170 and 2,150 mg/L, and median concentrations for zinc of 3,200 micrograms/L, for lead of 0 micrograms/L (minimum detection limit is 10 micrograms/L), for cadmium of 6 micrograms/L, for iron of 840 micrograms/L, for manganese of 440 micrograms/L, and for silica of 11 mg/L. No conclusive evidence of lateral migration of water from the mines into domestic well-water supplies in the shallow aquifer was found in the study area in Kansas. Analyses of water from public-supply wells tapping the deep aquifer did not indicate contamination with trace metals, although chemical analyses from four of six wells exhibited increasing trends through time in sulfate concentrations. These increases probably reflect localized leakage of water from the shallow aquifer along corroded or leaky well casings. Effects of abandoned lead and zinc mines on tributaries of the Spring River in the eastern area are most severe in Short Creek. Compared with water samples from three other major streams in the eastern area, a sample collected from Short Creek, 2 miles west of Galena, Kansas, during August 1981, contained the largest concentrations of dissolved sulfate (240 mg/L), zinc (25,000 micrograms/L), ca

Water Supply Paper↗

Arkansas and Landsat

Scenic Arkansas certainly lives up to its nickname, “The Natural State.” The Ozark Plateau and Ouachita Mountains boast stunning views, vast resources, and recreation. Hardwood and pine forests cover one-half of the State. The major rivers—Arkansas, Ouachita, Red, and White—offer recreation and navigation as they drain toward the Mississippi River, which forms the State’s eastern border. Smaller streams and rivers, reservoirs, and rice fields serve as homes for wildlife as well, including birds migrating along the Mississippi Flyway. Agriculture has always been a key industry in Arkansas, which is the top rice producer in the United States. Poultry, soybeans, cotton, cattle, and timber are among other agricultural products that contribute to the State’s economy. The aquaculture industry has diversified from just goldfish to more than 20 species of fish and crustaceans. Geological features include waterfalls, limestone caves, and the country’s only active diamond mine, Crater of Diamonds State Park, where visitors can keep any rock or mineral they find in the volcanic crater. Hot Springs National Park—within the city of Hot Springs—features thermal springs of water heated deep belowground that follow a fault line of the Ouachita Mountains up to the surface. Here are a few ways Landsat has benefited Arkansas.

Arkansas↗

Mapping abandoned uranium mine features using Worldview-3 imagery in portions of Karnes, Atascosa and Live Oak Counties, Texas

Worldview-3 (WV3) 16-band multispectral data were used to map exposed bedrock and mine waste piles associated with legacy open-pit mining of sandstone-hosted roll-front uranium deposits along the South Texas Coastal Plain. We used the “spectral hourglass” approach to extract spectral endmembers representative of these features from the image. This approach first requires calibrating the imagery to reflectance, then masking for vegetation, followed by spatial and spectral data reduction using a principal component analysis-based procedure that reduces noise and identifies homogeneous targets which are “pure” enough to be considered spectral endmembers. In this case, we used a single WV3 image which covered an ~11.5 km by ~19.5 km area of Karnes, Atascosa and Live Oak Counties, underlain by mined rocks from the Jackson Group and Catahoula Formation. Up to 58 spectral endmembers were identified using a further multi-dimensional class segregation method and were used as inputs for spectral angle mapper (SAM) classification. SAM classification resulted in the identification of at least 117 mine- and mine waste-related features, most of which were previously unknown. Class similarity was further evaluated, and the dominant minerals in each class were identified by comparison to spectral libraries and measured samples of actual Jackson Group uranium host rocks. Redundant classes were eliminated, and SAM was run a second time using a reduced set of 23 endmembers, which were found to map these same features as effectively as using the full 58 set of endmembers, but with significantly reduced noise and spectral outliers. Our classification results were validated by evaluating detailed scale mapping of three known mine sites (Esse-Spoonamore, Wright-McCrady and Garbysch-Thane) with published ground truth information about the vegetation cover, extent of erosion and exposure of waste pile materials and/or geologic information about host lithology and mineralization. Despite successful demonstration of the utility of WV3 data for inventorying mine features, additional landscape features such as bare agricultural fields and oil and gas drill pads were also identified. The elimination of such features will require combining the spectral classification maps presented in this study with high-quality topographic data. Also, the spectral endmembers identified during the course of this study could be useful for larger-scale mapping efforts using additional well-calibrated WV3 images beyond the coverage of our initial study area.

Texas↗

The geologic relationships of industrial mineral deposits and asbestos in the western united states

In recent years, U.S. regulatory agencies have placed emphasis on identifying and regulating asbestos dust exposures in the mining environment, with a particular focus upon industrial mineral deposits in which asbestos occurs as an accessory mineral. Because asbestos minerals form in specific geologic environments, only certain predictable types of industrial mineral deposits can potentially host asbestos mineralization. By applying a basic knowledge of asbestos geology, the costly and time consuming efforts of asbestos monitoring and analyses can be directed towards those mineral deposit types most likely to contain asbestos mineralogy, while saving efforts on the mineral deposits that are unlikely to contain asbestos. While the vast majority of industrial mineral deposits in the Western United States are asbestos-free, there are several types that can, in some instances, host asbestos mineralization, or be closely associated with it. These industrial mineral deposits include a few types of aggregate, dimension, and decorative stone, and some deposits of chromite-nickel, magnesite, nepheline syenite, olivine, rare earth elements, talc, vermiculite, and wollastonite.

Conference Paper↗

Mineral resource potential map of the Raywood Flat Roadless Areas, Riverside and San Bernardino counties, California

Geologic, geochemical, and geophysical studies within the Raywood "Flat Roadless Areas, together with an investigation of mines and prospects within the further planning area, resulted in (1) identification of nonmetallic mineral resources at a marble mine in the further planning area and (2) recognition of a small area in the recommended wilderness that has moderate potential for base-metal resources. Except for these two areas of identified and suspected resources, we did not observe indications of resource potential elsewhere in the Raywood Flat Roadless Areas. The area having nonmetallic mineral resources is in the vicinity of the Mill Creek mine near the northeastern boundary of the further planning area (B5-187); there, we identified marginal reserves of marble suitable for the production of lime and construction stone. The reserves are marginal because of their remote location and poor accessibility. Geologic mapping did not reveal any additional marble occurrences within the study area. The area having moderate potential for base-metal resources forms a small zone in the eastern part of the recommended wilderness (A5-187). Within this zone, evidence provided by stream-sediment geochemistry suggests that crystalline bedrocks in several drainages contain concentrations of metallic elements. Because the terrain is inaccessible and covered with dense brush, most of the bedrock in the specific drainages containing the geochemical anomalies could not be examined. Thus, although we infer that mineral occurrences exist in the drainage basins, we have little data on which to base an estimate of their extent and quality. Locally, the crystalline rocks probably contain hydrothermal veins or disseminated occurrences where lead, copper, molybdenum, tin, cobalt, bismuth, and arsenic have been concentrated. However, the geochemical anomalies for these metals are small, and the stream drainages also are relatively small. Therefore, the inferred occurrences of metallic minerals probably are small scale, scattered, and low grade. There is only low probability that the inferred mineral occurrences are large scale.

California↗

Geology and assessment of coal resources for the Cherokee coal bed in the Fort Union Formation, south-central Wyoming

The Cherokee coal bed is a locally thick and laterally continuous coal bed in the Overland Member of the Paleocene Fort Union Formation in south-central Wyoming. It represents a significant resource that is easily accessible and may be extractable through both surface and underground mining methods. A database of more than 600 data points, comprising coalbed methane wells, coal exploration drill holes, and measured sections, was compiled from a previously released geologic database and reinterpreted to provide a more detailed geologic model for the Cherokee coal bed. The thickest part of the Cherokee coal bed lies along the crest of the Wamsutter arch, an east-west trending anticlinal feature that separates the Great Divide subbasin to north from the Washakie subbasin to the south. The Cherokee coal bed consists of several laterally persistent benches separated by partings that range in thickness from one inch to greater than 100 feet. A series of detailed geologic cross sections through the study area show both the structural geology and the distribution and areal extent of the individual coal benches of the Cherokee coal bed. Data generated from the geologic model were used in stochastic geostatistical analyses to estimate the remaining or in-place coal resources. Certain parameters, as described later in the text, were applied to calculate available coal resources for surface and underground mining. This study is part of an ongoing process by the U.S. Geological Survey (USGS) to transition from a distance-based approach to a probabilistic approach for determining uncertainty in coal resource assessment. This probabilistic approach uses quantitative statistical methods to determine the potential range of uncertainty in coal resource estimates, whereas the distance-based approach does not provide any mathematical method to determine the range of uncertainty. Using stochastic geostatistical methods, utilizing 100 realizations or gridding iterations of the data, in-place resources were calculated, with a 90 percent probability, to be 15.261 ± 0.464 billion short tons (bst). Available coal resources tonnages were calculated using separate sets of criteria for surface and underground mining methods, based on probable mining parameters. Tonnage values were calculated based on estimated coal densities determined from available coal quality data. Available coal resources that meet the parameters for surface mining methods were calculated, with a 90 percent probability, to be 0.813 ± 0.038 bst. Available coal resources that meet the parameters for underground mining methods were calculated, with a 90 percent probability, to be 2.393 ± 0.055 bst. The calculations were based on estimates of the resources that meet the parameters for the optimum mining of the thickest coal benches of the Cherokee coal bed. This is depicted in a series of cross sections through the study area that show projected underground mining horizons in the Cherokee coal bed, based on the thickest combinations of individual coal benches.

Wyoming↗

A geologic field guide to S P Mountain and its lava flow, San Francisco Volcanic Field, Arizona

Introduction We created this guide to introduce the user to the San Francisco Volcanic Field as a terrestrial analog site for planetary volcanic processes. For decades, the San Francisco Volcanic Field has been used to teach scientists to recognize the products of common types of volcanic eruptions and associated volcanic features. The volcanic processes and products observed in this volcanic field are like those observed on lunar and Martian surfaces. As a result, this region has been a favored location for training National Aeronautics and Space Administration astronauts and engineers since the Apollo missions. Though the San Francisco Volcanic Field has more than 600 volcanic vents and flows, this guide will focus on S P Mountain (known locally as S P Crater, located ~30 miles north of Flagstaff, Arizona), one of the best preserved and most accessible of the volcanic cones and lava flows. S P Mountain presents both major types of basaltic eruptions—explosive and effusive—as well as some commonly associated tectonic landforms. We assume that the user has a basic understanding of geologic concepts and terminology. For more specialized terminology, we include tables showing the classification scheme for lava compositions, styles of eruptions, and tephra sizes (tables 1, 2, and 3). If a further introduction or refresher in volcanological terminology is desired, we suggest reviewing such terms on the U.S. Geological Survey Volcano Science Center’s online glossary ( https://volcanoes.usgs.gov/vsc/glossary/ ). One term requires clarification at the start of this guide—the term cinder. The terms cinder and cinder cone are widely used to describe the material and edifice produced by lava fountains. However, the term comes from the mining and construction industries and has no clear or formal definition. The international committees in geology and volcanology have chosen the term tephra to be the general term to describe pyroclasts (material ejected through a volcanic explosion or from a volcanic vent). Therefore, in this guide, we use the term tephra rather than cinder. This guide is outlined as follows: A brief tour of volcanism across the solar system A brief geologic history of the Colorado Plateau and San Francisco Volcanic Field Background on distributed volcanism and S P Mountain Driving directions and field stops Questions for discussion Each field stop includes a brief description, learning goals, tasks, and a summary of key points. At the end of the field guide are discussion points and questions that will ask the user to consider what they have observed and learned and how such knowledge can be used to better our understanding of geologic processes on other planetary bodies. Upon the completion of this field guide, we expect the user to: Have a basic understanding of the volcanic processes relevant to S P Mountain and its lava flow. Be able to identify different volcanic textures that are associated with tephra cones. Be aware of the different observations one can make at different scales (for example, observing lava flow morphology from aerial or satellite imagery versus tephra characteristics in the field).

Arizona↗

Hydrologic conditions and water-quality conditions following underground coal mining in the North Fork of the Right Fork of Miller Creek drainage basin, Carbon and Emery Counties, Utah, 2004-2005

In 2004 and 2005, the U.S. Geological Survey, in cooperation with the Bureau of Land Management, reassessed the hydrologic system in and around the drainage basin of the North Fork of the Right Fork (NFRF) of Miller Creek, in Carbon and Emery Counties, Utah. The reassessment occurred 13 years after cessation of underground coal mining that was performed beneath private land at shallow depths (30 to 880 feet) beneath the NFRF of Miller Creek. This study is a follow-up to a previous USGS study of the effects of underground coal mining on the hydrologic system in the area from 1988 to 1992. The previous study concluded that mining related subsidence had impacted the hydrologic system through the loss of streamflow over reaches of the perennial portion of the stream, and through a significant increase in dissolved solids in the stream. The previous study also reported that no substantial differences in spring-water quality resulted from longwall mining, and that no clear relationship between mining subsidence and spring discharge existed. During the summers of 2004 and 2005, the USGS measured discharge and collected water-quality samples from springs and surface water at various locations in the NFRF of Miller Creek drainage basin, and maintained a streamflow-gaging station in the NFRF of Miller Creek. This study also utilized data collected by Cyprus–Plateau Mining Corporation from 1992 through 2001. Of thirteen monitored springs, five have discharge levels that have not returned to those observed prior to August 1988, which is when longwall coal mining began beneath the NFRF of Miller Creek. Discharge at two of these five springs appears to fluctuate with wet and dry cycles and is currently low due to a drought that occurred from 1999–2004. Discharge at two other of the five springs did not increase with increased precipitation during the mid-1990s, as was observed at other monitored springs. This suggests that flowpaths to these springs may have been altered by land subsidence caused by underground coal mining. Analysis of possible impacts to the fifth spring were inconclusive due to a lack of data collected during the mid-1990s. Discharge at eight other monitored springs in the study area appears to be controlled mainly by climatic fluctuations and was generally near the value measured prior to 1988. Discharge at one of these eight springs is significantly greater than that measured during the longwall mining period. Concentrations of magnesium, calcium, sulfate, and dissolved solids at one undermined spring were elevated in relation to other springs in the study area. Dissolved solids concentration at this spring ranged from 539–709 milligrams per liter. Dissolved-solids concentration for all other springs in the study area ranged from 163 to 360 milligrams per liter and was near the median value measured prior to longwall mining beneath the NFRF of Miller Creek drainage basin. Baseflow measured at a streamflow-gaging station on the NFRF of Miller Creek located downstream of the mined area during the summer of 2004 was near 5 gallons per minute. Baseflow in 2005 increased to 7–8 gallons per minute, due to increased precipitation. This is slightly greater than the range of baseflow measured near the end of the longwall mining period which was approximately 3–5 gallons per minute. Seepage investigations carried out in the summer of 2004 and 2005 along the NFRF of Miller Creek showed a net loss of surface flow along the studied reach. Specific areas within the study reach had streamflow losses prior to longwall mining, however, the study reach as a whole was observed to gain in discharge when measured in 1986–1988, immediately before longwall mining began. The area where the greatest loss in discharge from the NFRF of Miller Creek occurred corresponds to an area where overburden (material overlying a deposit of useful geological materials or bedrock) is between 700 and 210 feet thick. Overburden thickness at the place where the streambed first dried up was approximately 600 feet thick. In 2004, approximately 1,600 ft of the streambed of the NFRF of Miller Creek was dry. Only 300 feet of the streambed was dry during the wetter year of 2005. Prior to longwall mining, no dry reaches were observed, though seepage loss was documented. Average discharge measured at a tributary to the NFRF of Miller Creek has increased from 1.6 gallons per minute measured during longwall mining to 7.2 gallons per minute measured in 2004–2005. During both years of this study, the lower reach of the stream regained flow from this tributary and from seepage gains. Water quality in the lower reach of the NFRF of Miller Creek downstream of the longwall-mined area, showed significantly higher concentrations of magnesium, calcium, sulfate, and strontium, in relation to water in the upper reach of the NFRF of Miller Creek and to the springs sampled in the area. Dissolved-solids concentration measured in the lower reach of the stream in 2004 and 2005 ranged from 1,880 to 2,220 milligrams per liter, while sulfate concentrations ranged from 1,090 to 1,320 mg/L. The maximum contaminant level for drinking water in the state of Utah for dissolved solids and sulfate is 2,000 and 1,000 mg/L respectively. Concentrations of these ions are slightly greater than those measured during and just following mining beneath the NFRF of Miller Creek drainage basin, but are significantly higher than those measured prior to mining. With the exception of strontium, dissolved metals concentrations in the NFRF of Miller Creek were similar to those measured in area springs. pH in the creek and at all spring sites was near neutral. Qualitative observations of the creek bottom suggest that mining-related activities have had little effect on vegetative growth.

Utah↗

A review of the lignite resources of Arkansas

This review of the lignite resources of Arkansas is a part of the U.S. Geological Survey's (USGS) National Coal Resource Assessment (NCRA) of the Gulf Coastal Plain Coal Province, which also includes coal-bearing areas in the states of Texas, Louisiana, Alabama, Mississippi, Tennessee, and Kentucky (see Ruppert et al., 2002 ; Dennen, 2009 ; and other chapters of this publication). Lignite mining is not planned in Arkansas in the immediate future, and the lignite resources of the state were not assessed in detail as part of the NCRA. This chapter includes reviews of the geology of the lignite-bearing units, historical mining, previous investigations of lignite resources, and coal quality. Palynological data for lignite samples collected in Arkansas as part of this work are presented in Table 1 .

Arkansas↗

Assessment of elemental concentrations in streams of the New Lead Belt in southeastern Missouri, 2002-05

Concerns about possible effects of lead-mining activities on the water quality of federally protected streams located in southeastern Missouri prompted a suite of multidisciplinary studies to be conducted by the U.S. Geological Survey. As part of this investigation, a series of biological studies were initiated in 2001 for streams in the current mining region and the prospecting area. In this report, results are examined for trace elements and other selected chemical measurements in sediment, surface water, and sediment interstitial (pore) water sampled between 2002 and 2005 in association with these biological studies. Compared to reference sites, fine sediments collected downstream from mining areas were enriched in metals by factors as large as 75 for cadmium, 62 for cobalt, 171 for nickel, 95 for lead, and 150 for zinc. Greatest metal concentrations in sediments collected in 2002 were from sites downstream from mines on Strother Creek, Courtois Creek, and the West Fork Black River. Sediments from sites on Bee Fork, Logan Creek, and Sweetwater Creek also were noticeably enriched in lead. Sediments in Clearwater Lake, at least 75 kilometers downstream from mining activity, had metal concentrations that were 1.5 to 2.1 times greater than sediments in an area of the lake with no upstream mining activity. Longitudinal sampling along three streams in 2004 indicated that sediment metal concentrations decreased considerably a few kilometers downstream from mining activities; however, in Strother Creek some metals were still enriched by a factor of five or more as far as 13 kilometers downstream from the Buick tailings impoundment. Compared with 2002 samples, metals concentrations were dramatically lower in sediments collected in 2004 at an upper West Fork Black River site, presumably because beneficiation operations at the West Fork mill ceased in 2000. Concentrations of metals and sulfate in sediment interstitial (pore) waters generally tracked closely with metal concentrations in sediments. Metals, including cobalt, nickel, lead, and zinc, were elevated substantially in laboratory-produced pore waters of fine sediments collected near mining operations in 2002 and 2004. Passive diffusion samplers (peepers) buried 4 to 6 centimeters deep in riffle-run stream sediments during 2003 and 2005 had much lower pore-water metal concentrations than the laboratory-produced pore waters of fine sediments collected in 2002 and 2004, but each sampling method produced similar patterns among sites. The combined mean concentration of lead in peeper samples from selected sites located downstream from mining activities for six streams was about 10-fold greater than the mean of the reference sites. In most instances, metals concentrations in surface water and peeper water were not greatly different, indicating considerable exchange between the surface water and pore water at the depths and locations where peepers were situated. Passive sampling probes used to assess metal lability in pore waters of selected samples during 2004 sediment toxicity tests indicated that most of the filterable lead in the laboratory-prepared pore water was relatively non-labile, presumably because lead was complexed by organic matter, or was present as colloidal species. In contrast, large percentages of cobalt and nickel in pore water appeared to be labile. Passive integrative samplers deployed in surface water for up to 3 weeks at three sites in July 2005 confirmed the presence of elevated concentrations of labile metals downstream from mining operations on Strother Creek and, to a lesser extent, Bee Fork. These samplers also indicated a considerable increase in metal loadings occurred for a few days at the Strother Creek site, which coincided with moderate increases in stream discharges in the area.

Scientific Investigations Report↗

Assessment of nonpoint source chemical loading potential to watersheds containing uranium waste dumps associated with uranium exploration and mining, Browns Hole, Utah

During August of 2008, 35 solid-phase samples were collected from abandoned uranium waste dumps, undisturbed geologic background sites, and adjacent streambeds in Browns Hole in southeastern Utah. The objectives of this sampling program were (1) to assess impacts on human health due to exposure to radium, uranium, and thorium during recreational activities on and around uranium waste dumps on Bureau of Land Management lands; (2) to compare concentrations of trace elements associated with mine waste dumps to natural background concentrations; (3) to assess the nonpoint source chemical loading potential to ephemeral and perennial watersheds from uranium waste dumps; and (4) to assess contamination from waste dumps to the local perennial stream water in Muleshoe Creek. Uranium waste dump samples were collected using solid-phase sampling protocols. Solid samples were digested and analyzed for major and trace elements. Analytical values for radium and uranium in digested samples were compared to multiple soil screening levels developed from annual dosage calculations in accordance with the Comprehensive Environmental Response, Compensation, and Liability Act's minimum cleanup guidelines for uranium waste sites. Three occupancy durations for sites were considered: 4.6 days per year, 7.0 days per year, and 14.0 days per year. None of the sites exceeded the radium soil screening level of 96 picocuries per gram, corresponding to a 4.6 days per year exposure. Two sites exceeded the radium soil screening level of 66 picocuries per gram, corresponding to a 7.0 days per year exposure. Seven sites exceeded the radium soil screening level of 33 picocuries per gram, corresponding to a 14.0 days per year exposure. A perennial stream that flows next to the toe of a uranium waste dump was sampled, analyzed for major and trace elements, and compared with existing aquatic-life and drinking-water-quality standards. None of the water-quality standards were exceeded in the stream samples.

Utah↗

Groundwater–surface-water exchange and the geologic setting of northern Minnesota's lakes, wetlands, and streams—Modern-day relevance of Tom Winter's legacy

Tom Winter spent nearly 50 years conducting research in earth science, and he specialized in the exchange between groundwater and surface water. Tom's highly productive career began in Minnesota. This fi eld trip revisits many of the places where Tom conducted his early research and demonstrates the continuing relevance of that research. Stops and topics include the groundwater infl uence on the record low stage of White Bear Lake, the contribution of groundwater to continually rising water levels in an abandoned open-pit iron mine, hydrogeology of the Shingobee headwaters aquatic ecosystem research site, hydrogeology of Lake Sallie, geology associated with the Pillager water gap, and the hydrogeology of Little Rock Lake.

GSA Field Guides↗

Geologic cross sections showing the concentrations of As, Cd, Co, Cu, Cr, Fe, Mo, Ni, Pb, and Zn in acid-insoluble residues of Paleozoic rocks within the Doniphan/Eleven Point Ranger District of the Mark Twain National Forest, Missouri, USA

This report is a product of a U.S. Geological Survey investigation that is focused on characterizing the potential environmental impacts of lead-zinc mining within the Doniphan/Eleven Point ranger district of the Mark Twain national forest. The elemental concentrations of iron (Fe), arsenic (As), cadmium (Cd), cobalt (Co), copper (Cu), chromium (Cr), nickel (Ni), lead (Pb), and zinc (Zn) in acidinsoluble residues are shown for boreholes along two geologic cross sections within Doniphan/Elevan Point ranger district (Figure 1). The purpose of this report is to characterize, in a general sense, the distribution of economically and environmentally important elements within the rocks and aquifers of the Doniphan/Eleven Point ranger district

Missouri↗

Geology and zinc-lead deposits in the Catfish Creek area, Dubuque County, Iowa

A detailed geologic study was begun in 1951 by the U.S. Geological Survey in cooperation with the Iowa Geological Survey to appraise the potentialities of the Iowa part of the Wisconsin-Illinois-Iowa zinc-lead district for (1) zinc ore in rock strata that contain pitch-and-flat zinc ore bodies elsewhere in the mining district and (2) joint-controlled lead and zinc ore like that mined extensively during the 19th century in Dubuque County, Iowa. This investigation is an outgrowth of a geologic study of the entire district, begun in 1942 by the U.S. Geological Survey.

Iowa↗

Geology and mineral evaluation of the Wadi Bidah district, southern Hijaz quadrangle, Kingdom of Saudi Arabia

The Wadi Bidah district in southwest Saudi Arabia contains several ancient mines and mineral-prospects. The Precambian rocks of the district are steeply dipping and highly folded and faulted. They are divided into three major units: (1) older metavolcanic rocks, (2) metasedimentary rocks, and (3) younger metavolcanic rocks. Massive sulfide-type deposits show stratigraphic control and are found in metasedimentary rocks and in the younger metavolcanic rocks. There appears to be a close genetic relationship between the sulfide deposits and volcanism. Deposits containing copper, zinc, gold, and silver are indicated by geologic mapping and by shallow diamond drill holes in two of the ancient mine localities. The ore estimate for the district is 2.55 million short tons computed to depths that range from 79 to 150 meters. It seems probable that deeper drilling of the indicated deposits and drilling of other outlined target areas would add substantially to the ore reserves.

Open-File Report↗