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USGS2003

Statistical sampling to characterize recent United States land-cover change

The U.S. Geological Survey, in conjunction with the U.S. Environmental Protection Agency, is conducting a study focused on developing methods for estimating changes in land-cover and landscape pattern for the conterminous United States from 1973 to 2000. Eleven land-cover and land-use classes are interpreted from Landsat imagery for five sampling dates. Because of the high cost and potential effect of classification error associated with developing change estimates from wall-to-wall land-cover maps, a probability sampling approach is employed. The basic sampling unit is a 20 x 20 km area, and land cover is obtained for each 60 x 60 m pixel within the sampling unit. The sampling design is stratified based on ecoregions, and land-cover change estimates are constructed for each stratum. The sampling design and analyses are documented, and estimates of change accompanied by standard errors are presented to demonstrate the methodology. Analyses of the completed strata suggest that the sampling unit should be reduced to a 10 x 10 km block, and poststratified estimation and regression estimation are viable options to improve precision of estimated change. ?? 2003 Elsevier Inc. All rights reserved.

Remote Sensing of Environment↗

USGS2004

Evaluation of multidimensional transport through a field-scale compacted soil liner

A field-scale compacted soil liner was constructed at the University of Illinois at Urbana-Champaign by the U.S. Environmental Protection Agency (USEPA) and Illinois State Geological Survey in 1988 to investigate chemical transport rates through low permeability compacted clay liners (CCLs). Four tracers (bromide and three benzoic acid tracers) were each added to one of four large ring infiltrometers (LRIs) while tritium was added to the pond water (excluding the infiltrometers). Results from the long-term transport of Br - "> Br - from the localized source zone of LRI are presented in this paper. Core samples were taken radially outward from the center of the Br - "> Br - LRI and concentration depth profiles were obtained. Transport properties were evaluated using an axially symmetric transport model. Results indicate that (1) transport was diffusion controlled; (2) transport due to advection was negligible and well within the regulatory limits of k sat ⩽ 1 × 10 - 7 cm / s ; "> k sat ⩽ 1 × 10 − 7 cm / s; (3) diffusion rates in the horizontal and vertical directions were the same; and (4) small positioning errors due to compression during soil sampling did not affect the best fit advection and diffusion values. The best-fit diffusion coefficient for bromide was equal to the molecular diffusion coefficient multiplied by a tortuosity factor of 0.27, which is within 8% of the tortuosity factor (0.25) found in a related study where tritium transport through the same liner was evaluated. This suggests that the governing mechanisms for the transport of tritium and bromide through the CCL were similar. These results are significant because they address transport through a composite liner from a localized source zone which occurs when defects or punctures in the geomembrane of a composite system are present.

Journal of Geotechnical and Geoenvironmental Engin↗

USGS2012

Evaluating the accotink creek restoration project for improving water quality, in-stream habitat, and bank stability

Increased urbanization results in a larger percentage of connected impervious areas and can contribute large quantities of stormwater runoff and significant quantities of debris and pollutants (e.g., litter, oils, microorganisms, sediments, nutrients, organic matter, and heavy metals) to receiving waters. To improve water quality in urban and suburban areas, watershed managers often incorporate best management practices (BMPs) to reduce the quantity of runoff as well as to minimize pollutants and other stressors contained in stormwater runoff. It is well known that land-use practices directly impact urban streams. Stream flows in urbanized watersheds increase in magnitude as a function of impervious area and can result in degradation of the natural stream channel morphology affecting the physical, chemical, and biological integrity of the stream. Stream bank erosion, which also increases with increased stream flows, can lead to bank instability, property loss, infrastructure damage, and increased sediment loading to the stream. Increased sediment loads may lead to water quality degradation downstream and have negative impacts on fish, benthic invertebrates, and other aquatic life. Accotink Creek is in the greater Chesapeake Bay and Potomac watersheds, which have strict sediment criteria. The USEPA (United States Environmental Protection Agency) and USGS (United States Geological Survey) are investigating the effectiveness of stream restoration techniques as a BMP to decrease sediment load and improve bank stability, biological integrity, and in-stream water quality in an impaired urban watershed in Fairfax, Virginia. This multi-year project continuously monitors turbidity, specific conductance, pH, and water temperature, as well as biological and chemical water quality parameters. In addition, physical parameters (e.g., pebble counts, longitudinal and cross sectional stream surveys) were measured to assess geomorphic changes associated with the restoration. Data from the pre-construction and initial post-construction phases are presented in this report. ?? 2007 ASCE.

Conference Paper↗

USGS2025

Base-flow sampling to enhance understanding of the groundwater flow component of nitrogen loading in small watersheds draining into Long Island Sound

Excessive nitrogen discharge is a major concern for the Long Island Sound. Programs have been implemented to reduce point sources of nitrogen to the sound, but little is known about the nonpoint sources. This study aims to better understand the current groundwater contributions of nitrogen from nonpoint sources in the Long Island Sound watershed. During the spring and summer of 2022, the U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency, collected water-quality samples to analyze nutrients (nitrogen and phosphorus), chloride, and bromide at 45 stations in the Long Island Sound watershed in Connecticut, New York, and Rhode Island. The stations were in small drainage watersheds (5 to 30 square kilometers) in the southern part of the Long Island Sound watershed. During two separate synoptic sampling events, water-quality samples and instantaneous streamflow measurements were collected under base-flow conditions (where the streamflow is dominated by groundwater inputs rather than overland flow or runoff flow). One sampling event was in the nongrowing season (April 24–25, 2022), and the other was in the growing season (June 30–July 1, 2022). To calculate instantaneous nitrogen loads and yields, streamflow was measured at the time of sample collection. Nitrogen concentrations, loads, and yields varied among sampling stations and by season. Total filtered nitrogen concentrations were generally lower in the nongrowing season (from less than 0.14 to 1.9 milligrams per liter) than in the growing season (from less than 0.23 to 3.0 milligrams per liter). Nitrate plus nitrite concentrations showed little variation between the nongrowing and growing seasons. Unfiltered ammonia plus organic nitrogen concentrations were generally lower in the nongrowing season (from less than 0.07 to 0.83 milligram per liter) than in the growing season (from 0.11 to 0.98 milligram per liter). In contrast, total filtered and unfiltered nitrogen loads and yields were higher in the nongrowing season than during the growing season, likely because streamflows were higher during the nongrowing season. Total unfiltered nitrogen yields during the nongrowing season ranged from less than 0.15 to 5.0 kilograms per square kilometer per day. Total unfiltered nitrogen yields during the growing season ranged from less than 0.12 to 2.5 kilograms per square kilometer per day. Total filtered nitrogen yields during the nongrowing season ranged from less than 0.13 to 5.2 kilograms per square kilometer per day. Total filtered nitrogen yields during the growing season ranged from less than 0.06 to 2.5 kilograms per square kilometer per day.

Connecticut, New York, Rhode Island↗

USGS2005

Occurrence of selected pharmaceutical and non-pharmaceutical compounds, and stable hydrogen and oxygen isotope ratios, in a riverbank filtration study, Platte River, Nebraska, 2001 to 2003, Volume 1

Although studied extensively in recent years in Europe, the occurrence of endocrine disrupters and other organic wastewater compounds in the environment in the United States is not well documented. To better understand the efficiency of riverbank filtration with respect to endocrine disrupting compounds and to evaluate the use of riverbank filtration as an effective means of drinking-water treatment, a study was conducted during 2001-2003 by the U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency and the City of Lincoln, at an established riverbank-filtration well field with horizontal collector wells and vertical wells. This study provides information that will be useful for (1) increased understanding of the processes and factors important in controlling the transport of endocrine disrupters, such as pesticides and pharmaceuticals during riverbank filtration, (2) better understanding of the physical and chemical processes that affect riverbank-filtration efficiency, and (3) managing the water resources of the eastern Platte River Basin. This report presents analytical methods and data collected during the study. Data are presented as generalized statistics and in figures showing temporal variations. Sites from which water-quality samples were collected for this study included wastewater sites (a cattle feedlot lagoon, a hog confinement lagoon, and wastewater-treatment plant effluent), surface-water sites (Platte River, Salt Creek, and Loup Power Canal), ground-water sites (one collector well and three vertical wells), and drinking-water sites (raw and finished). Field water-quality properties were measured in samples from these sites. Pharmaceutical compounds were detected often in the wastewater-treatment plant effluent. Surface and ground water showed low-level concentrations of pharmaceuticals. Finished drinking-water samples did not contain detectable concentrations of pharmaceuticals except for low levels of cotinine and caffeine. Antibiotics were found in some of the wastewater samples and twice in Salt Creek. Antibiotics were not detected in any samples from the Platte River or the well field. Surface-water samples were analyzed for total organic carbon and ground-water samples were analyzed for dissolved organic carbon. Samples from all sites were analyzed for major ions. Herbicides commonly detected in surface, ground, and drinking water included acetachlor, alachlor, atrazine, and metolachlor as well as degradates of these compounds. Most of the samples from wastewater sites were found to contain predominantly acetamide degradates. High concentrations of several organic wastewater indicator compounds were detected at the wastewater sites and in Salt Creek. Several organic wastewater indicator compounds were detected multiple times in samples from the Platte River. Bromoform, a by-product of disinfection in the treatment plant, was found in samples from the finished drinking water. Stable hydrogen isotope ratios show a range in seasonal variation of -73.6 per mill to -38.1 per mill relative to Vienna Standard Mean Ocean Water (VSMOW) reference water and -69.2 per mill to -46.5 per mill for surface water and ground water, respectively. Oxygen isotope ratios for surface-water samples varied between -9.86 per mill and -5.05 per mill. Stable oxygen isotope ratios of ground waters varied between -9.62 per mill and -5.81 per mill.

Nebraska↗

USGS2005

Occurrence of selected pharmaceutical and non-pharmaceutical compounds, and stable hydrogen and oxygen isotope ratios in a riverbank filtration study, Platte River, Nebraska, 2002 to 2005, Volume 2

This document is the second volume of a data series report that describes the data collected during a study conducted during 2001 through 2005 by the U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency and the City of Lincoln, at an established riverbank-filtration well field with horizontal collector wells and vertical wells. The data were collected as part of a study designed to help researchers better understand the efficiency of riverbank filtration with respect to endocrine disrupting compounds and to evaluate the use of riverbank filtration as an effective means of drinking-water treatment. This study provides information that will be useful for (1) increased understanding of the processes and factors controlling the transport of endocrine disrupters, such as pesticides and pharmaceuticals during riverbank filtration, (2) better understanding of the physical and chemical processes that affect riverbank-filtration efficiency, and (3) managing the water resources of the eastern Platte River Basin. This report presents analytical methods and additional data for pharmaceuticals, dissolved organic carbon (DOC), ultraviolet absorbance at 254 nanometer (nm) wavelength (UV254), specific ultraviolet absorbance (SUVA), nitrilotriacetic acid (NTA), ethylenediaminetetraacetic acid (EDTA), nonylphenol ethoxycarboxylates (NPECs), and stable hydrogen and oxygen isotope ratios that were not available at the time of publication of Volume 1 in the data series. Data are presented as generalized statistics and in figures showing temporal variations. Sites from which water-quality samples were collected for this study included wastewater sites (a cattle feedlot lagoon, a hog confinement lagoon, and wastewater-treatment plant effluent), surface-water sites (Platte River, Salt Creek, and Loup Power Canal), ground-water sites (one collector well and five vertical wells), and drinking-water sites (raw and finished). Field water-quality properties also were measured in samples from these sites. Pharmaceuticals detected at least once in samples collected from the Platte River included 1,7-dimethylxanthine, acetaminophen, caffeine, carbamazapine, and cotinine. Among the ground-water samples, pharmaceutical compounds detected at low concentrations in at least one sample included 1,7-dimethylxanthine, acetaminophen, carbamazapine, and trimethoprim. When analyzing for non-pharmaceutical compounds in samples from the wastewater sites, the wastewater-treatment plant effluent samples had the highest concentrations of each of NTA, EDTA, and NPECs compounds. Surface-water samples from Salt Creek had higher concentrations of EDTA and NPECs than samples from the Platte River. NTA was not detected in any samples from the ground-water sites. EDTA was detected in all samples from all wells. Detectable concentrations of EDTA were also observed in all samples from the raw water and finished water.

Nebraska↗

USGS2008

Environmental and Biological Data of the Nutrient Enrichment Effects on Stream Ecosystems Project of the National Water Quality Assessment Program, 2003-04

In 2000, the U.S. Environmental Protection Agency began the process of developing regional nutrient criteria for streams and rivers. In response to concerns about nutrients by the U.S. Environmental Protection Agency and others, the U.S. Geological Survey National Water Quality Assessment Program began studying the effects of nutrient enrichment on agricultural stream ecosystems to aid in the understanding of how nutrients affect the biota in agricultural streams. Streams within five study areas were sampled either in 2003 or 2004. These five study areas were located within six NAWQA study units: the combined Apalachicola-Chattahoochee-Flint River Basin (ACFB) and Georgia-Florida Coastal Plain Drainages (GAFL), Central Columbia Plateau?Yakima River Basin (CCYK), Central Nebraska Basins (CNBR), Potomac River?Delmarva Peninsula (PODL), and the White-Miami River Basin (WHMI). Data collected included nutrients (nitrogen and phosphorous) and other chemical parameters, biological samples (chlorophyll, algal assemblages, invertebrate assemblages, and some fish assemblages), stream habitat, and riparian and basin information. This report describes and presents the data collected from these study areas.

Data Series↗

USGS2010

Water-quality data for selected streams in the Mississippi Alluvial Plain ecoregion, northwestern Mississippi, September – October 2007

From September through October 2007, the U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency, collected and analyzed water-quality samples from streams in the Yazoo River basin within the Mississippi Alluvial Plain ecoregion in northwestern Mississippi. Water-quality samples were collected at 56 sites in the study area and analyzed for various physical and chemical characteristics including, but not limited to, suspended sediment, nutrients, and chlorophyll a. Additionally, water temperature, pH, specific conductance, and dissolved oxygen data were measured at 28 of the sites using multiparameter water-quality meters at 30-minute intervals for a minimum of 48 hours. Data collected for this project will be used in the development of water-quality criteria for nutrients. The nutrient data will enhance existing datasets and support evaluation of cause and effect relations for nutrient criteria development. In addition, these indicators will assist in the development and evaluation of restoration and remediation plans for water bodies not meeting their designated uses, as stated in the U.S. Environmental Protection Agency's Clean Water Act Section 303(d).

Mississippi↗

USGS2015

Estuarine bed-sediment-quality data collected in New Jersey and New York after Hurricane Sandy, 2013

This report describes a reconnaissance study of estuarine bed-sediment quality conducted June–October 2013 in New Jersey and New York after Hurricane Sandy in October 2012 to assess the extent of contamination and the potential long-term human and ecological impacts of the storm. The study, funded through the Disaster Relief Appropriations Act of 2013 (PL 113-2), was conducted by the U.S. Geological Survey in cooperation with the U.S. Environmental Protection Agency and the National Oceanographic and Atmospheric Administration. In addition to presenting the bed-sediment-quality data, the report describes the study design, documents the methods of sample collection and analysis, and discusses the steps taken to assure the quality of the data. Bed-sediment samples were collected from June to October 2013 from 167 estuarine sites extending from Cape May, New Jersey, to the New York Harbor and the eastern end of Long Island. Each sampling location and study region was characterized by using geographic information to identify potential contaminant sources. Characterizations included land cover, locations and types of businesses (industrial, financial, and others), spills (sewage, chemical, and others), bulk storage facilities, effluent discharges within 2 kilometers of the sampling point, and discharges within inundated and non-inundated regions near the sampling location. Samples were analyzed for particle size, total organic carbon, metals and trace elements, semivolatile organic compounds, wastewater compounds, hormones, and sediment toxicity. Samples were also screened using x-ray fluorescence, Fourier transform infrared spectroscopy, and x-ray diffraction. In addition, bioassays for endocrine disruptors and protein phosphatase 2A inhibition were conducted. The study was designed to provide the data needed to understand the extent and sources of contamination resulting from Hurricane Sandy, to compare the chemistry and toxicity of estuarine bed sediments before and after the storm, and to evaluate the usefulness of rapid screening and bioassay approaches in disaster settings.

New Jersey, New York↗

USGS2010

Regional climate change-Science in the Southeast

Resource managers are at the forefront of a new era of management. They must consider the potential impacts of climate change on the Nation's resources and proactively develop strategies for dealing with those impacts on plants, animals, and ecosystems. This requires rigorous, scientific understanding of environmental change. The role of the U.S. Geological Survey (USGS) in this effort is to analyze climate-change data and develop tools for assessing how changing conditions are likely to impact resources. This information will assist Federal, State, local, and tribal partners manage resources strategically. The 2008 Omnibus Budget Act and Secretarial Order 3289 established a new network of eight Department of Interior Regional Climate Science Centers to provide technical support for resource managers. The Southeast Regional Assessment Project (SERAP) is the first regional assessment to be funded by the USGS National Climate Change and Wildlife Science Center (http://nccw.usgs.gov/). The USGS is working closely with the developing Department of Interior Landscape Conservation Cooperatives to ensure that the project will meet the needs of resource managers in the Southeast. In addition, the U.S. Fish and Wildlife Service is providing resources to the SERAP to expand the scope of the project.

Fact Sheet↗

USGS2010

Facts About Invasive Bighead and Silver Carps

The U.S. Geological Survey (USGS) scientists at the Columbia Environmental Research Center (CERC), Columbia, Missouri, carry out basic and applied research on the ecology of invasive fishes in the Missouri and Mississippi river basins. Emphasis is placed on improving understanding of the life cycles of bighead and silver carp to provide information needed to manage these aggressively invasive species. USGS scientists collaborate with Federal and State management agencies and universities, nationally and internationally, to fill critical science information gaps.

Fact Sheet↗

USGS2020

Continuous nitrate monitoring in groundwater and potential contribution to surface-water nitrogen loads in Mason County, Illinois

Illinois has some of the most productive farmland in the country. The use of fertilizers to improve crop production has increased, which has resulted in an increase in the concentration of nitrogen in many streams and aquifers. The U.S. Geological Survey, in cooperation with the Illinois Environmental Protection Agency, is continuously monitoring (one reading every 15 minutes) the concentration of nitrate plus nitrite, as nitrogen, in a groundwater well and assessing the potential contribution to surface-water nitrogen loads. Continuous monitoring of the nitrate concentration allows for the collection of a larger dataset in comparison to periodic or event-based sampling. This fact sheet describes the data collection methods, describes the overall experimental design, and displays data collected for the study. The analysis of continuous data improves understanding of the fate and transport of nitrate.

Illinois↗

USGS2022

Loss of street tree canopy increases stormwater runoff

Urban forests have largely been overlooked for the role they play in reducing stormwater runoff volume by using hydrologic processes such as interception (rainfall intercepted by tree canopy), evapotranspiration (the transfer of water from vegetation into the atmosphere) and infiltration (percolation of rainwater into the Earth’s soil). Early research into the effects of trees on urban stormwater runoff used simple estimates based on assumptions of canopy coverage and design storm criteria. In a review of available literature on how capable urban trees are at reducing runoff, the Center for Watershed Protection (2017) found only six studies; three of them used measured data from a single plot, and the other three used models. When identifying gaps in research on the role of trees in stormwater management, Kuehler and others (2017) highlighted the need for studies that scale the local effects of urban trees to the larger sewershed catchment area, allowing a more holistic understanding of the urban tree canopy effects on hydrology. For these reasons, the U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency, U.S. Forest Service, and the University of Wisconsin, quantified the effect of removing urban street trees and their canopy on stormwater generation in a medium-density residential area. Using a paired-catchment experimental design, rainfall-runoff relations were characterized in two medium-density residential catchments in Fond du Lac, Wisconsin, during May through September in 2018–20. Results of the study are detailed in Selbig and others (2022). During the calibration phase, hydrograph metrics from paired runoff events were used to develop the relation between the control and test catchments with street trees in place. The ability to measure changes to the rainfall-runoff response after removal of tree canopy was made possible by an aggressive tree removal program by the city as a response to rapid infestation from the Agrilus planipennis (emerald ash borer). In March 2020, a total of 31 street trees were removed at the onset of the treatment period, resulting in a loss of 2,990 square meters of canopy over streets, driveways, sidewalks, and grassed areas.

Wisconsin↗

USGS2025

The Long Island Sound and Watershed Metadata map application

The Long Island Sound and its watershed encompass an area of about 17,000 square miles and include the Connecticut, Housatonic, and Thames Rivers, which all drain to the sound. Dozens of organizations from government agencies, nonprofits, and Tribal Nations have developed projects and monitoring programs to analyze and protect the water resources of the watershed and sound. The abundance of data and lack of an existing searchable index require a centralized metadata repository to allow users to find water resources data more efficiently. The U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency and the Long Island Sound Study, has created an interactive map application to visualize and search for metadata information across organizations working to monitor and protect the Long Island Sound.

Connecticut, Massachusetts, New Hampshire, New Yor↗

USGS1977

Major active faults and seismicity in and near the Big Fork-Avon area, Missoula-Kalispell region, northwestern Montana

This is one of a series of environmental maps of a study area that overlies parts of Flathead, Lake, Missoula, and Powell Counties, northwestern Montana. The area extends from Big Fork, in Lake County, on the north to Avon, in Powell County, on the south, essentially as outline in figure 1. The environmental study was undertaken by the U.S. Geological Survey in response to a request from the Regional Planning Association of Western Montana who believed that the data gathered would be of significant use to county land-use planner.s

Montana↗

USGS2004

Evaluating a Radar-Based, Non Contact Streamflow Measurement System in the San Joaquin River at Vernalis, California

Accurate measurement of flow in the San Joaquin River at Vernalis, California, is vital to a wide range of Federal and State agencies, environmental interests, and water contractors. The U.S. Geological Survey uses a conventional stage-discharge rating technique to determine flows at Vernalis. Since the flood of January 1997, the channel has scoured and filled as much as 20 feet in some sections near the measurement site resulting in an unstable stage-discharge rating. In response to recent advances in measurement techniques and the need for more accurate measurement methods, the Geological Survey has undertaken a technology demonstration project to develop and deploy a radar-based streamflow measuring system on the bank of the San Joaquin River at Vernalis, California. The proposed flow-measurement system consists of a ground-penetrating radar system for mapping channel geometries, a microwave radar system for measuring surface velocities, and other necessary infrastructure. Cross-section information derived from ground penetrating radar provided depths similar to those measured by other instruments during the study. Likewise, surface-velocity patterns and magnitudes measured by the pulsed Doppler radar system are consistent with near surface current measurements derived from acoustic velocity instruments. Since the ratio of surface velocity to mean velocity falls to within a small range of theoretical value, using surface velocity as an index velocity to compute river discharge is feasable. Ultimately, the non-contact radar system may be used to make continuous, near-real-time flow measurements during high and medium flows. This report documents the data collected between April 14, 2002 and May 17, 2002 for the purposes of testing this radar based system. Further analyses of the data collected during this field effort will lead to further development and improvement of the system.

Open-File Report↗

USGS2005

PCB concentrations in Pere Marquette River and Muskegon River watersheds, 2002

Polychlorinated biphenyl compounds (PCBs) are a class of209 individual compounds (known as congeners) for which there are no known natural sources. PCBs are carcinogenic and bioaccumulative compounds. For over 40 years, PCBs were manufactured in the United States. The flame resistant property of PCBs made them ideal chemicals for use as flame-retardants, and as coolants and lubricants in transformers and other electrical equipment. PCBs were also used in heating coils, carbonless paper, degreasers, varnishes, lacquers, waterproofing material, and cereal boxes. In addition, they were frequently used in the manufacturing of plastics, adhesives, and paints. During the manufacturing period of PCBs, these chemicals entered the environment though atmospheric release during manufacturing and burning of PCB products, leaks and spills, and improper disposal. Although PCB manufacturing was banned over 20 years ago, PCBs still enter the environment from hazardous waste sites, improper disposals of PCB-containing products, weathering of asphalt and other substances containing PCBs, burning of PCB containing products, leakage from old equipment, leaching from landfills, and release from contaminated sediments. PCBs do not readily break down in the environment, thus remain there for long periods of time. A small amount may remain dissolved in water but most adhere to organic particles and bottom sediments. In sufficient concentrations, PCBs affect human, wildlife, and aquatic health. PCBs accumulate in fatty tissues of animals and fish and are passed on to those that eat them. PCBs are animal teratogens and potentially carcinogenic. They can cause death of animals, fish, and birds; death or low growth rate of plants; shortened lifespan; reproductive problems; and lower fertility. Women who are exposed to high levels of PCBs may have babies with slightly lower birth weights and transfer the PCBs through the breast milk, which may affect the immune system and motor development of the child. Rule 323.1057 (Toxic Substances) of the Part 4. Water Quality Standards gives procedure for calculating water-quality values to protect human, wildlife and aquatic life. For total PCB, the applicable Rule 57 water-quality value is the human cancer value (HCV=0.26 ng/L), In 2002, U. S. Geological Survey (USGS) and Michigan Department of Environmental Quality (MDEQ) cooperatively planned and executed a monitoring program for PCBs in water and sediment from the Pere Marquette River and Muskegon River watersheds. The Pere Marquette and Muskegon River are in the west central part of Michigan's Lower Peninsula (fig. 1). The Pere Marquette River watershed is about 750 square miles, and the Muskegon River is about 2700 square miles. Both rivers are popular recreational waters, and the Pere Marquette River is a Michigan designated Natural River (Part 305 of the Natural Rivers and Environmental Protection Act 451 of 1994).

Michigan↗

USGS2006

Proceedings of the 4th New World Luminescence Dating and Dosimetry Workshop, Denver, Colorado, May 31 June 2, 2006

Introduction: Optically stimulated luminescence (OSL) is one of a class of measurements known as stimulated phenomena. Such phenomena may be stimulated thermally or optically and the reader is referred to works by Aitken (1998) and Botter-Jensen and others (2003) for more detail. In recent years OSL has become a popular procedure for the determination of environmental radiation doses absorbed by archeological and geological materials in an attempt to date these materials. The first OSL measurements on quartz and feldspar were made using an argon ion-laser (Huntley et al., 1985). However, the development of cheaper stimulation systems based first on filtered lamps and then on light- emitting diodes (LEDs) (Spooner, et al., 1990; Botter-Jensen, and others, 1999) has led to a massive expansion in OSL dating applications. The abstracts in this volume represent presentations from a workshop held in May-June 2006, at the Denver Federal Center, Denver, Colorado, in which OSL methodologies and applications were summarized and integrated to provide a current synthesis of the OSL science being applied throughout North America. The workshop, sponsored by the U.S. Geological Survey Crustal Imaging and Characterization Team and North Dakota State University, was open to all scientists interested in OSL dating techniques and radiation dosimetry. Participants included thirty-six research scientists and students in geology, archaeology, and physics from the U.S. Geological Survey, Los Alamos National Labs, Kentucky Geological Survey, eight universities in the United States, one university in Canada, one university in India, and Riso National Labs of Denmark. The workshop included two keynote speakers: Dr. Ashok Singhvi (Physical Research Laboratory, Ahmedabad, India) spoke on 'Some Unexplored Methodological Aspects and Some New Applications of Luminescence Dating,' while Dr. Jim Feathers (University of Seattle, WA) spoke on OSL Dating of Sediments From Paleoindian Sites in Brazil. The workshop encouraged everyone to interact more to develop a broader perspective on the types of research and the problems encountered when reporting OSL ages. This meeting follows the first North American Luminescence Dating Workshop held in Tulsa, OK, by Oklahoma State University (2001), in Albuquerque, NM, by Los Alamos National Labs (2002), and in Halifax, Nova Scotia, by Dalhousie University (2004, with a name change to New World Luminescence Dating Workshop). These workshops were interspersed with the international meetings on luminescence that were held in Reno, NV, (2002), and Cologne, Germany; (2005).

Open-File Report↗