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David L. Fey

Publications and source records attributed to David L. Fey.

At least 37 records · Page 2Linked to original sources
USGS2010

Evaluation of the extent of contamination caused by historical mining in catchments of central Colorado

The U.S. Geological Survey conducted an assessment of stream water and sediment quality in central Colorado, an area of about 54,000 km2. The study area is focused on small tributary catchments in the Rocky Mountains. The Colorado Mineral belt, a northeast-trending mineralized zone that experienced base- and precious-metal mining at the beginning of the late 1800s and early 1900s, cuts diagonally across the geologic trend in the study area. The goal of this study was to compare water and sediment quality in background catchments with those which have been mined. Water and sediment data from 200 catchments, and data from macroinvertebrates from more than 100 catchments, provided ample data for evaluation of the effects of mining on water and sediment quality. Focused sampling was conducted during low-flow conditions in the summers of 2004-2007. Samples were collected from catchments that (1) were underlain largely by a single lithologic unit, (2) contained hydrothermally altered rock and had been prospected, and (3) contained historical mines. Geochemical data determined from catchments that did not contain hydrothermal alteration or historical mines met water-quality criteria and recommended sediment-quality guidelines and showed small variations in base-metal concentrations. Hydrothermal alteration and mineralization typically are associated with igneous rocks that have intruded older bedrock. Base-metal concentrations were elevated in sediment from catchments underlain by hydrothermally altered rock. Catchments affected by historical mining contained highly elevated base-metal concentrations. Classification of catchments on the basis of mineral deposit types proved to be an efficient and accurate method for discriminating catchments that had degraded water and sediment quality. Only about 4.5 percent of the study area has been affected by historical mining, whereas a larger portion of the study area is underlain by hydrothermally altered rock. Weathering of QSP-altered catchments release metals and result in naturally elevated geochemical background concentrations in both sediment and water. The presence of hydrothermal alteration is shown to be a major consideration in the selection of sites for the determination of geochemical background.

Conference Paper↗
USGS2009

Metal contamination and post-remediation recovery in the Boulder River watershed, Jefferson County, Montana

The legacy of acid mine drainage and toxic trace metals left in streams by historical mining is being addressed by many important yet costly remediation efforts. Monitoring of environmental conditions frequently is not performed but is essential to evaluate remediation effectiveness, determine whether clean-up goals have been met, and assess which remediation strategies are most effective. Extensive pre- and post-remediation data for water and sediment quality for the Boulder River watershed in southwestern Montana provide an unusual opportunity to demonstrate the importance of monitoring. The most extensive restoration in the watershed occurred at the Comet mine on High Ore Creek and resulted in the most dramatic improvement in aquatic habitat. Removal of contaminated sediment and tailings, and stream-channel reconstruction reduced Cd and Zn concentrations in water such that fish are now present, and reduced metal concentrations in streambed sediment by a factor of c. 10, the largest improvement in the district. Waste removals at the Buckeye/Enterprise and Bullion mine sites produced limited or no improvement in water and sediment quality, and acidic drainage from mine adits continues to degrade stream aquatic habitat. Recontouring of hillslopes that had funnelled runoff into the workings of the Crystal mine substantially reduced metal concentrations in Uncle Sam Gulch, but did not eliminate all of the acidic adit drainage. Lead isotopic evidence suggests that the Crystal mine rather than the Comet mine is now the largest source of metals in streambed sediment of the Boulder River. The completed removal actions prevent additional contaminants from entering the stream, but it may take many years for erosional processes to diminish the effects of contaminated sediment already in streams. Although significant strides have been made, additional efforts to seal draining adits or treat the adit effluent at the Bullion and Crystal mines would need to be completed to achieve the desired restoration.

Montana↗
USGS2009

Geochemical data for samples collected in 2008 near the concealed pebble porphyry Cu-Au-Mo deposit, Southwest Alaska

In the summer of 2007, the U.S. Geological Survey (USGS) began an exploration geochemical research study over the Pebble porphyry copper-gold-molybdenum deposit. This report presents the analytical data collected in 2008. The Pebble deposit is world class in size, and is almost entirely concealed by tundra, glacial deposits, and post-Cretaceous volcanic rocks. The Pebble deposit was chosen for this study because it is concealed by surficial cover rocks, is relatively undisturbed (except for exploration company drill holes), is a large mineral system, and is fairly well-constrained at depth by the drill hole geology and geochemistry. The goals of this study are to 1) determine whether the concealed deposit can be detected with surface samples, 2) better understand the processes of metal migration from the deposit to the surface, and 3) test and develop methods for assessing mineral resources in similar concealed terrains. The analytical data are presented as an integrated Microsoft Access 2003 database and as separate Excel files.

Alaska↗
USGS2009

An orientation soil survey at the Pebble Cu-Au-Mo porphyry deposit, Alaska

Soil samples were collected in 2007 and 2008 along three traverses across the giant Pebble Cu-Au-Mo porphyry deposit. Within each soil pit, four subsamples were collected following recommended protocols for each of ten commonly-used and proprietary leach/digestion techniques. The significance of geochemical patterns generated by these techniques was classified by visual inspection of plots showing individual element concentration by each analytical method along the 2007 traverse. A simple matrix by element versus method, populated with a value based on the significance classification, provides a method for ranking the utility of methods and elements at this deposit. The interpretation of a complex multi-element dataset derived from multiple analytical techniques is challenging. An example of vanadium results from a single leach technique is used to illustrate the several possible interpretations of the data.

Alaska↗
USGS2008

Ground- and surface-water chemistry of Handcart Gulch, Park County, Colorado, 2003-2006

As part of a multidisciplinary project to determine the processes that control ground-water chemistry and flow in mineralized alpine environments, ground- and surface-water samples from Handcart Gulch, Colorado were collected for analysis of inorganic solutes and water and dissolved sulfate stable isotopes in selected samples. The primary aim of this study was to document variations in ground-water chemistry in Handcart Gulch and to identify changes in water chemistry along the receiving stream of Handcart Gulch. Water analyses are reported for ground-water samples collected from 12 wells in Handcart Gulch, Colorado. Samples were collected between August 2003 and October 2005. Water analyses for surface-water samples are reported for 50 samples collected from Handcart Gulch and its inflows during a low-flow tracer injection on August 6, 2003. In addition, water analyses are reported for three other Handcart Gulch stream samples collected in September 2005 and March 2006. Reported analyses include field parameters (pH, specific conductance, temperature, dissolved oxygen, and Eh), major and trace constituents, oxygen and hydrogen isotopic composition of water and oxygen and sulfur isotopic composition of dissolved sulfate. Ground-water samples from this study are Ca-SO4 type and range in pH from 2.5 to 6.8. Most of the samples (75 percent) have pH values between 3.3 and 4.3. Surface water samples are also Ca-SO4 type and have a narrower range in pH (2.7?4.0). Ground- and surface-water samples vary from relatively dilute (specific conductance of 68 ?S/cm) to concentrated (specific conductance of 2,000 ?S/cm).

Colorado↗
USGS2008

Preliminary analytical results for a mud sample collected from the LUSI Mud Volcano, Sidoarjo, East Java, Indonesia

On May 29, 2006, mud and gases began erupting unexpectedly from a vent 150 meters away from a hydrocarbon exploration well near Sidoarjo, East Java, Indonesia. The eruption, called the LUSI (Lumpur 'mud'-Sidoarjo) mud volcano, has continued since then at rates as high as 160,000 m3 per day. At the request of the United States Department of State, the U.S. Geological Survey (USGS) has been providing technical assistance to the Indonesian Government on the geological and geochemical aspects of the mud eruption. This report presents initial characterization results of a sample of the mud collected on September 22, 2007, as well as inerpretive findings based on the analytical results. The focus is on characteristics of the mud sample (including the solid and water components of the mud) that may be of potential environmental or human health concern. Characteristics that provide insights into the possible origins of the mud and its contained solids and waters have also been evaluated.

East Java↗
USGS2008

Geochemical data for samples collected in 2007 near the concealed pebble porphyry Cu-Au-Mo deposit, southwest Alaska

In the summer of 2007, the U.S. Geological Survey (USGS) began an exploration geochemical research study over the Pebble porphyry copper-gold-molydenum (Cu-Au-Mo) deposit in southwest Alaska. The Pebble deposit is extremely large and is almost entirely concealed by tundra, glacial deposits, and post-Cretaceous volcanic and volcaniclastic rocks. The deposit is presently being explored by Northern Dynasty Minerals, Ltd., and Anglo-American LLC. The USGS undertakes unbiased, broad-scale mineral resource assessments of government lands to provide Congress and citizens with information on national mineral endowment. Research on known deposits is also done to refine and better constrain methods and deposit models for the mineral resource assessments. The Pebble deposit was chosen for this study because it is concealed by surficial cover rocks, it is relatively undisturbed (except for exploration company drill holes), it is a large mineral system, and it is fairly well constrained at depth by the drill hole geology and geochemistry. The goals of the USGS study are (1) to determine whether the concealed deposit can be detected with surface samples, (2) to better understand the processes of metal migration from the deposit to the surface, and (3) to test and develop methods for assessing mineral resources in similar concealed terrains. This report presents analytical results for geochemical samples collected in 2007 from the Pebble deposit and surrounding environs. The analytical data are presented digitally both as an integrated Microsoft 2003 Access? database and as Microsoft 2003 Excel? files. The Pebble deposit is located in southwestern Alaska on state lands about 30 km (18 mi) northwest of the village of Illiamna and 320 km (200 mi) southwest of Anchorage (fig. 1). Elevations in the Pebble area range from 287 m (940 ft) at Frying Pan Lake just south of the deposit to 1146 m (3760 ft) on Kaskanak Mountain about 5 km (5 mi) to the west. The deposit is in an area of relatively subdued topographic relief with an elevation of around 300 m (1000 ft). This portion of Alaska is part of the subarctic regime mountains division, Yukon intermontane plateaus-tayga-meadow province ecoregion, as defined by Bailey (U.S. Forest Service, 2007). Between June 28th and July 12th, 2007, scientists from the USGS collected soil, water, stream sediment, vegetation, heavy-mineral concentrate, till, and rock samples from the deposit area. This report contains analytical results for soil, water, stream sediment, and vegetation samples. Analyses for the heavy-mineral concentrate, till, and rock samples are still in progress. The sampling was undertaken during relatively dry and stable weather conditions. Only minor scattered rain showers occurred during the sampling period, so surface conditions were largely unaffected by weather. The predominant sample media collected were soils and surface waters. Soil and water (mostly from ponds and springs, some from small creeks) samples were collected along a single 7.8 km-long (4.8 mi) east-west traverse across the Pebble East and Pebble West zones and from more distal background areas around Koktuli and Kaskanak Mountains. Sample sites are shown on figure 2 and plate 1, and locality coordinates are provided in the accompanying Access and Excel files named FieldSite. Water samples were analyzed by USGS laboratories with one subset analyzed by Activation Laboratories (Actlabs), as indicated below. Soils and stream sediments were analyzed for their total content by SGS Minerals Services under a contract with the USGS. Soil samples were also leached by selected partial-extraction leaching procedures and then analyzed by several commercial laboratories, as described below. Vegetation samples were analyzed as indicated below.

Alaska↗
USGS2008

Reconnaissance study of water quality in the mining-affected Aries River Basin, Romania

The Aries River basin of western Romania has been subject to mining activities as far back as Roman times. Present mining activities are associated with the extraction and processing of various metals including Au, Cu, Pb, and Zn. To understand the effects of these mining activities on the environment, this study focused on three objectives: (1) establish a baseline set of physical parameters, and water- and sediment-associated concentrations of metals in river-valley floors and floodplains; (2) establish a baseline set of physical and chemical measurements of pore water and sediment in tailings; and (3) provide training in sediment and water sampling to personnel in the National Agency for Mineral Resources and the Rosia Poieni Mine. This report summarizes basin findings of physical parameters and chemistry (sediment and water), and ancillary data collected during the low-flow synoptic sampling of May 2006.

Aries River Basin↗
USGS2007

Mining-impacted sources of metal loading to an alpine stream based on a tracer-injection study, Clear Creek County, Colorado

Base flow water in Leavenworth Creek, a tributary to South Clear Creek in Clear Creek County, Colorado, contains copper and zinc at levels toxic to aquatic life. The metals are predominantly derived from the historical Waldorf mine, and sources include an adit, a mine-waste dump, and mill-tailings deposits. Tracer-injection and water-chemistry synoptic studies were conducted during low-flow conditions to quantify metal loads of mining-impacted inflows and their relative contributions to nearby Leavenworth Creek. During the 2-year investigation, the adit was rerouted in an attempt to reduce metal loading to the stream. During the first year, a lithium-bromide tracer was injected continuously into the stream to achieve steady-state conditions prior to synoptic sampling. Synoptic samples were collected from Leavenworth Creek and from discrete surface inflows. One year later, synoptic sampling was repeated at selected sites to evaluate whether rerouting of the adit flow had improved water quality. The largest sources of copper and zinc to the creek were from surface inflows from the adit, diffuse inflows from wetland areas, and leaching of dispersed mill tailings. Major instream processes included mixing between mining- and non-mining-impacted waters and the attenuation of iron, aluminum, manganese, and othermetals by precipitation or sorption. One year after the rerouting, the Zn and Cu loads in Leavenworth Creek from the adit discharge versus those from leaching of a large volume of dispersed mill tailings were approximately equal to, if not greater than, those before. The mine-waste dump does not appear to be a major source of metal loading. Any improvement that may have resulted from the elimination of adit flow across the dump was masked by higher adit discharge attributed to a larger snow pack. Although many mine remediation activities commonly proceed without prior scientific studies to identify the sources and pathways of metal transport, such strategies do not always translate to water-quality improvements in the stream. Assessment of sources and pathways to gain better understanding of the system is a necessary investment in the outcome of any successful remediation strategy.

Colorado↗
USGS2007

Geochemistry of Surface and Ground Water in Cement Creek from Gladstone to Georgia Gulch and in Prospect Gulch, San Juan County, Colorado

In San Juan County, Colo., the effects of historical mining continue to contribute metals to ground water and surface water. Previous research by the U.S. Geological Survey identified ground-water discharge as a significant pathway for the loading of metals to surface water in the upper Animas River watershed from both acid-mine drainage and acid-rock drainage. In support of this ground-water research effort, Prospect Gulch was selected for further study and the geochemistry of surface and ground water in the area was analyzed as part of four sampling plans: (1) ten streamflow and geochemistry measurements at five stream locations (four locations along Cement Creek plus the mouth of Prospect Gulch from July 2004 through August 2005), (2) detailed stream tracer dilution studies in Prospect Gulch and in Cement Creek from Gladstone to Georgia Gulch in early October 2004, (3) geochemistry of ground water through sampling of monitoring wells, piezometers, mine shafts, and springs, and (4) samples for noble gases and tritium/helium for recharge temperatures (recharge elevation) and ground-water age dating. This report summarizes all of the surface and ground-water data that was collected and includes: (1) all sample collection locations, (2) streamflow and geochemistry, (3) ground-water geochemistry, and (4) noble gas and tritium/helium data.

Colorado↗
USGS2007

Selected field parameters from streams and preliminary analytical data from water and macroinvertebrate samples, Central Colorado Assessment Project, task, 2004 and 2005

The U.S. Geological Survey (USGS) Central Colorado Assessment Project (CCAP) began in October 2003 and is planned to last through September 2008. One major goal of this project is to compare the relationships between surface-water chemistry and aquatic fauna in mined and unmined areas. To accomplish this goal, we are conducting a State-scale reconnaissance sampling program, in which we are collecting water and macroinvertebrate samples. Selected results from the first two years of project analyses are reported here. We plan to develop statistical models and use geographic information system (GIS) technology to quantify the relationships between ecological indicators of metal contamination in Rocky Mountain streams and water quality, landscape and land-use characteristics (for example, mine density, geology, geomorphology, vegetation, topography). Our research will test the hypothesis that physicochemical variables and ecological responses to metal concentrations in stream water in Rocky Mountain streams are ultimately determined largely by historical land uses.

Colorado↗
USGS2006

Predicting toxic effects of copper on aquatic biota in mineralized areas by using the Biotic Ligand Model

The chemical speciation of metals influences their biological effects. The Biotic Ligand Model (BLM) is a computational approach to predict chemical speciation and acute toxicological effects of metals on aquatic biota. Recently, the U.S. Environmental Protection Agency incorporated the BLM into their regulatory water-quality criteria for copper. Results from three different laboratory copper toxicity tests were compared with BLM predictions for simulated test-waters. This was done to evaluate the ability of the BLM to accurately predict the effects of hardness and concentrations of dissolved organic carbon (DOC) and iron on aquatic toxicity. In addition, we evaluated whether the BLM and the three toxicity tests provide consistent results. Comparison of BLM predictions with two types of Ceriodaphnia dubia toxicity tests shows that there is fairly good agreement between predicted LC50 values computed by the BLM and LC50 values determined from the two toxicity tests. Specifically, the effect of increasing calcium concentration (and hardness) on copper toxicity appears to be minimal. Also, there is fairly good agreement between the BLM and the two toxicity tests for test solutions containing elevated DOC, for which the LC50 is 3-to-5 times greater (less toxic) than the LC50 for the lower-DOC test water. This illustrates the protective effects of DOC on copper toxicity and demonstrates the ability of the BLM to predict these protective effects. In contrast, for test solutions with added iron there is a decrease in LC50 values (increase in toxicity) in results from the two C. dubia toxicity tests, and the agreement between BLM LC50 predictions and results from these toxicity tests is poor. The inability of the BLM to account for competitive iron binding to DOC or DOC fractionation may be a significant shortcoming of the BLM for predicting site- specific water-quality criteria in streams affected by iron-rich acidic drainage in mined and mineralized areas.

Conference Paper↗
USGS2005

Results of chemical and isotopic analyses of sediment and water from alluvium of the Canadian River near a closed municipal landfill, Norman, Oklahoma

Results of physical and chemical analyses of sediment and water collected near a closed municipal landfill at Norman, Oklahoma are presented in this report. Sediment analyses are from 40 samples obtained by freeze-shoe coring at 5 sites, and 14 shallow (depth <1.3 m) sediment samples. The sediment was analyzed to determine grain size, the abundance of extractable iron species and the abundances and isotopic compositions of forms of sulfur. Water samples included pore water from the freeze-shoe core, ground water, and surface water. Pore water from 23 intervals of the core was collected and analyzed for major and trace dissolved species. Thirteen ground-water samples obtained from wells within a few meters of the freeze-shoe core sites and one from the landfill were analyzed for major and trace elements as well as the sulfur and oxygen isotope composition of dissolved sulfate. Samples of surface water were collected at 10 sites along the Canadian River from New Mexico to central Oklahoma. These river-water samples were analyzed for major elements, trace elements, and the isotopic composition of dissolved sulfate.

Oklahoma↗
USGS2005

Geochemical assessment of metals and dioxin in sediment from the San Carlos Reservoir and the Gila, San Carlos, and San Francisco Rivers, Arizona

In October 2004, we sampled stream-bed sediment, terrace sediment, and sediment from the San Carlos Reservoir to determine the spatial and chronological variation of six potentially toxic metals-Cu, Pb, Zn, Cd, As, and Hg. Water levels in the San Carlos Reservoir were at a 20-year low at an elevation of 2,409 ft (734.3 m). Four cores were taken from the reservoir: one from the San Carlos River arm, one from the Gila River arm, and two from the San Carlos Reservoir just west of the Pinal County line. Radioisotope chronometry (7Be, 137Cs, and 210Pb) conducted on sediment from the reservoir cores provides a good chronological record back to 1959. Chronology prior to that, during the 1950s, is based on our interpretation of the 137Cs anomaly in reservoir cores. During and prior to the 1950s, the reservoir was dry and sediment-accumulation rates were irregular; age control based on radioisotope data was not possible. We recovered sediment at the base of one 4-m-long core that may date back to the late 1930s. The sedimentological record contains two discrete events, one about 1978-83 and one about 1957, where the Cu concentration in reservoir sediment exceeded recommended sediment quality guidelines and should have had an effect on sensitive aquatic and benthic organisms. Concentrations of Zn determined in sediment deposited during the 1957(?) event also exceeded recommended sediment quality guidelines. Concentration data for Cu from the four cores clearly indicate that the source of this material was upstream on the Gila River. Lead isotope data, coupled with the geochemical data from a 2M HCl-1 percent H2O2 leach of selected sediment samples, show two discrete populations of data. One represents the dominant sediment load derived from the Safford Valley, and a second reflects sediment derived from the San Francisco River. The Cu concentration spikes in the reservoir cores have chemical and Pb isotope signatures that indicate that deposits in a porphyry copper deposit from the Morenci district is the likely source of these Cu-rich sedimentary deposits. Copper concentrations and Pb isotope data in premining terrace-sediment deposits indicate that the Cu peaks could not have resulted from erosion of premining sediment from terrace deposits downstream on the Gila River. The chemical and Pb isotope data also indicate that agricultural practices in the Safford Valley have resulted in an increased sediment load to the Gila River since large-scale farming began, prior to the time when the San Carlos Reservoir was built. Analyses of dioxin, which is an impurity in one of the herbicides used in the late 1960s and early 1970s, were completed in sediment from one of the cores in the reservoir to determine whether any of these pesticide residues have accumulated in the reservoir sediment. Dioxin concentration is expressed in terms of its toxicity (toxic equivalent concentration or TEQ). Concentrations of dioxin in the sediment ranged from 0.68 to 1.37 pg/g and are less than any of the benchmark concentrations recommended as threshold values for adverse effects of dioxin in sediment (> 2.5-10 pg/g).

Scientific Investigations Report↗
USGS2004

Geochemistry of mine waste and mill tailings, meadow deposits, streambed sediments, and the general hydrology and water quality for the Frohner Meadows area, upper Lump Gulch, Jefferson County, Montana

Frohner Meadows, an area of low-topographic gradient subalpine ponds and wetlands in glaciated terrane near the headwaters of Lump Gulch (a tributary of Prickly Pear Creek), is located about 15 miles west of the town of Clancy, Montana, in the Helena National Forest. Mining and ore treatment of lead-zinc-silver veins in granitic rocks of the Boulder batholith over the last 120 years from two sites (Frohner mine and the Nellie Grant mine) has resulted in accumulations of mine waste and mill tailings that have been distributed downslope and downstream by anthropogenic and natural processes. This report presents the results of an investigation of the geochemistry of the wetlands, streams, and unconsolidated-sediment deposits and the hydrology, hydrogeology, and water quality of the area affected by these sources of ore-related metals. Ground water sampled from most shallow wells in the meadow system contained high concentrations of arsenic, exceeding the Montana numeric water-quality standard for human health. Transport of cadmium and zinc in ground water is indicated at one site near Nellie Grant Creek based on water-quality data from one well near the creek. Mill tailings deposited in upper Frohner Meadow contribute large arsenic loads to Frohner Meadows Creek; Nellie Grant Creek contributes large arsenic, cadmium, and zinc loads to upper Frohner Meadows. Concentrations of total-recoverable cadmium, copper, lead, and zinc in most surface-water sites downstream from the Nellie Grant mine area exceeded Montana aquatic-life standards. Nearly all samples of surface water and ground water had neutral to slightly alkaline pH values. Concentrations of arsenic, cadmium, lead, and zinc in streambed sediment in the entire meadow below the mine waste and mill tailings accumulations are highly enriched relative to regional watershed-background concentrations and exceed consensus-based, probable-effects concentrations for streambed sediment at most sites. Cadmium, copper, and zinc typically are adsorbed to the surface coatings of streambed-sediment grains. Mine waste and mill tailings contain high concentrations of arsenic, cadmium, copper, lead, and zinc in a quartz-rich matrix. Most of the waste sites that were sampled had low acid-generating capacity, although one site (fine-grained mill tailings from the Nellie Grant mine deposited in the upper part of lower Frohner Meadows) had extremely high acid-generating potential because of abundant fine-grained pyrite. Two distinct sites were identified as metal sources based on streambed-sediment samples, cores in the meadow substrate, and mine and mill-tailings samples. The Frohner mine and mill site contribute material rich in arsenic and lead; similar material from the Nellie Grant mine and mill site is rich in cadmium and zinc.

Montana↗