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USGS2022

Science mission requirements for a globally ranging, riserless drilling vessel for U.S. Scientific Ocean Drilling

Through the collection and analysis of shallow and deep subseafloor sediments, rocks, fluids, and life, scientific ocean drilling has enriched our understanding of the complex Earth system. Among other achievements, scientific ocean drilling has documented the history of Earth’s climate, the waxing and waning of polar ice sheets, the past changes in ocean and atmospheric circulation, the existence and function of microbial life in the subseafloor, the compositional variations in Earth’s crust and underlying mantle, and the physical and chemical processes acting at subduction zones, including those associated with tsunamigenic earthquakes. Over the decades, more than 12,000 articles that depend on analyses of scientific ocean drilling samples and geophysical data have been published, many detailing breakthrough contributions to global knowledge about the Earth system. Approximately 45% of these publications were led by U.S.-affiliated authors (International Ocean Discovery Program Publication Services, 2021). Since the mid-1980s, the workhorse of this multidisciplinary, international research effort has been the riserless D/V JOIDES Resolution, operated by Texas A&M University with funding from the U.S. National Science Foundation (NSF). D/V JOIDES Resolution has conducted the vast majority of scientific ocean drilling expeditions and collected most of the scientific cores over that period, including 82% of the expeditions and 93% of the cores in the last decade alone, despite being one of three platforms that is operated within the International Ocean Discovery Program. However, D/V JOIDES Resolution is approaching the end of its useful life. With a strong commitment to continue scientific ocean drilling beyond the end of the current phase, the community developed a document outlining the research frontiers that should be pursued. Exploring Earth by Scientific Ocean Drilling: 2050 Science Framework (Koppers and Coggon, 2020) describes seven scientific strategic objectives that focus on understanding interconnections within the Earth system and five flagship initiatives that integrate these objectives into long-term research efforts that address issues facing society. Additional elements in the 2050 Science Framework, including STEM education, workforce development, technology development, and innovative applications of data analytics, will advance the goals of scientific ocean drilling. Addressing the 2050 Science Framework also requires building partnerships with allied U.S. and international science programs and strengthening existing ones. To implement a significant portion of the 2050 Science Framework, the U.S. scientific community seeks to lease or acquire a newly built, globally ranging, state-of-the art, riserless drilling vessel. The many and varied technical and human resources requirements for successful accomplishment of scientific and educational goals summarized in this document and described in detail in the 2050 Science Framework require broad community input and careful consideration. Following receipt of NSF’s formal Request for Assistance to the United States Science Support Program (USSSP), the U.S. scientific ocean drilling community conducted a one-year exercise to identify its national scientific needs and priorities in order to determine the Science Mission Requirements (SMRs) presented here. This community effort included: (1) a U.S. community-wide survey to identify the specific operational and technical capabilities critical to addressing science in the 2050 Science Framework; (2) a series of online workshops focusing on critical capabilities identified by the survey; and (3) a large in-person workshop to synthesize the results of the survey and the virtual workshops (Appendix 1). The approach was designed to reach as many participants as possible. Overall, 278 survey responses were received from U.S. community members, representing 104 unique institutions from 39 states and the District of Columbia, and 137 unique individuals participated in the workshops (Appendix 2). The results of this effort comprise two classes of SMRs: Foundational Science Mission Requirements and Primary Science Mission Requirements. Foundational SMRs define minimum criteria for a new riserless drilling vessel that can address significant portions of the 2050 Science Framework. Primary SMRs build upon the Foundational SMRs and will create more robust science opportunities and data collection capabilities, will increase progress in addressing the 2050 Science Framework objectives, and will provide more real-time ship-to-shore interaction to improve science productivity, engagement, and outreach. Modern safety and environmental standards, including meeting standards to access protected waters such as exclusive economic zones, extended continental shelves, or high latitudes, while being cognizant of the vessel’s environmental footprint. Safe and efficient operations in global locations and in water depths from 70 m to 6000+ m, with total drill string length of at least 7000 m. High-quality core and data collection from a range of key subseafloor environments. Advanced heave compensation, dynamic positioning, and drill pipe stability. Modern mud and cement/casing systems. Critical onboard measurements for safety, operational decision-making, documentation of ephemeral properties, mission-specific science, and long-term science goals that extend beyond a single expedition. Designated and appropriate space for sample and data preservation. Highly skilled onboard personnel, including technical staff for curation and core handling; support for safety, time-sensitive, and critical shipboard measurements; computer support; equipment and instrument repair; application support; and data assurance. Primary Science Mission Requirements include: Flexible shipboard space for laboratories and on deck to ensure safe, successful implementation of diverse science objectives and operations. Minimizing contamination of recovered samples. Over-the-side capabilities for science-supporting technology (e.g., remotely operated vehicles, water- column sampling, sediment-water interface sampling). Downhole logging and measurements. Expanded borehole observatory capabilities. Reliable and consistent ship-to-shore communications. NSF’s investment in a new globally ranging, riserless drilling vessel will have a powerful economic multiplier effect, including the infusion of additional science support funds in the United States for training and research, the development of new technologies and tools, and the associated scientific and technical workforce development. The skills and knowledge gained through scientific ocean drilling are translatable to careers in fields such as sustainable energy development (e.g., geothermal and offshore wind), carbon sequestration, data management and cyberinfrastructure, biotechnology, communications, science education, policy, hazard mitigation, and environmental management. The United States is a leader in a well-established and internationally collaborative scientific ocean drilling community. A modern, globally ranging, riserless drilling vessel will allow the United States to expand its leadership position, address broad scientific questions that current capabilities preclude, and cultivate equitable international, multidisciplinary collaborations that will ensure scientific ocean drilling’s future success.

Report↗
USGS1985

Wildlife health implications of sewage disposal in wetlands

Wildlife health concerns associated with disposal of sewage effluent in wetlands are of three primary types: (1) introduction of pathogens, (2) introduction of pollutants that adversely impact on host body defense mechanisms, and (3) changes in the physical and chemical properties of wetlands that favor the development and maintenance of disease problems. Unlike the situation with human health concerns, introduction of pathogens is not the major concern regarding wildlife health. Instead, the focus of attention needs to be directed at environmental changes likely to take place as a result of effluent discharges into different types of wetlands. Unless these changes are adequately addressed from a disease perspective, marshes utilized for sewage disposal could become disease incubators and wildlife death traps. This result would be unfortunate because the backlash would likely negate the potentially beneficial aspects of the use of sewage wastewater for the creation of new wetlands and have a severe impact on progress being made towards evaluation of the compatibility of wildlife and sewage effluents.

Book chapter↗
USGS2016

Identify potential lock treatment options to prevent movement of aquatic invasive species through the Chicago Area Waterways System (CAWS)

Introduction The Illinois River is a primary tributary of the Mississippi River, connecting with the Mississippi at Grafton, Illinois. The headwaters of the river are at the confluence of the Des Plaines and Kankakee Rivers in eastern Grundy County, Illinois. Approximately 273 miles long, it runs through the heart of Illinois and is the connection between the Mississippi River and Lake Michigan in the Great Lakes basin. Because of this connection, there is concern about the potential for introduced aquatic species in one basin to migrate through this connection into the other basin. A prime example of this are the Asian carps, which were introduced into commercial fishing ponds in Arkansas in the 1970s and, following escape, are now making their way up the Mississippi, Illinois, and Missouri Rivers. Options are being investigated to minimize or prevent non-native aquatic species from invading either basin through the Illinois River connection and eventually having detrimental impacts on the basin into which they migrate. The Illinois River has a series of locks and dams that are used to facilitate the navigation of commercial and recreational shipping from Chicago to Beardstown, Illinois. One option under consideration is to develop a lock treatment process that stops aquatic invasive species from entering (and moving through) the Chicago Area Waterway System (CAWS), while at the same time not unduly impeding the movement of barges and other boat traffic between Lake Michigan and the Mississippi River. The purpose this report was to evaluate the feasibility of using chemical and (or) physical treatments to determine if a sufficiently efficacious option could be used to prevent aquatic invasive species from being transported through the locks. Approximately 30 chemical and physical control options were evaluated on the basis of nine factors ranging from viability for use on a large scale, rapid lethality, human health effects, and potential damage to lock structures and vessel hulls. Compatibility of the various options was also evaluated to assess the possibility that options could be combined to enhance efficacy. Engineering requirements were not considered as part of this evaluation. The available information suggests that hot water at 43 °C and ozone are the most feasible options.

Chicago Area Waterway System↗
USGS2008

Framework for Evaluating Water Quality of the New England Crystalline Rock Aquifers

Little information exists on regional ground-water-quality patterns for the New England crystalline rock aquifers (NECRA). A systematic approach to facilitate regional evaluation is needed for several reasons. First, the NECRA are vulnerable to anthropogenic and natural contaminants such as methyl tert-butyl ether (MTBE), arsenic, and radon gas. Second, the physical characteristics of the aquifers, termed 'intrinsic susceptibility', can lead to variable and degraded water quality. A framework approach for characterizing the aquifer region into areas of similar hydrogeology is described in this report and is based on hypothesized relevant physical features and chemical conditions (collectively termed 'variables') that affect regional patterns of ground-water quality. A framework for comparison of water quality across the NECRA consists of a group of spatial variables related to aquifer properties, hydrologic conditions, and contaminant sources. These spatial variables are grouped under four general categories (features) that can be mapped across the aquifers: (1) geologic, (2) hydrophysiographic, (3) land-use land-cover, and (4) geochemical. On a regional scale, these variables represent indicators of natural and anthropogenic sources of contaminants, as well as generalized physical and chemical characteristics of the aquifer system that influence ground-water chemistry and flow. These variables can be used in varying combinations (depending on the contaminant) to categorize the aquifer into areas of similar hydrogeologic characteristics to evaluate variation in regional water quality through statistical testing.

Open-File Report↗
USGS2011

Groundwater quality of southeastern Wyoming

Groundwater is an important resource for domestic, municipal, stock, and irrigation uses in southeastern Wyoming. Thirty-seven percent of water used in the tri-County area, which includes Laramie, Platte, and Goshen Counties, is from groundwater. Most groundwater use in the tri-County area is withdrawn from three primary aquifer groups: Quaternary-age unconsolidated-deposit aquifers, Tertiary-age units of the High Plains aquifer system, and Upper Cretaceous bedrock aquifers (Lance Formation and Fox Hills Sandstone). Authors include selected physical properties and chemicals found in water samples, describe sources and importance, and report maximum levels established by the U.S. Environmental Protection Agency. They also show concentration ranges for selected physical properties and chemicals in samples collected from the three primary aquifer groups in the tri-County area.

Wyoming↗
USGS2020

Inventory and analysis of groundwater resources: Theodore Roosevelt National Park, North Dakota

Industrial and commercial developments in western North Dakota potentially could affect the sources of water that contribute to wells, spring flow, and seeps within Theodore Roosevelt National Park. Without basic water resources data, accurately predicting the effects of water withdrawals and water quality concerns related to industrial and commercial developments near the park would be challenging. Water resources in the park include surface water and groundwater. The Little Missouri River and its tributaries cross all three Theodore Roosevelt National Park units and are the primary surface-water features in the park. Groundwater resources include well discharges, springs, and seeps. The geology and hydrogeology of Theodore Roosevelt National Park are defined by the surrounding Williston Basin. Four aquifers are sources of groundwater to the park: unconsolidated aquifers including alluvial systems, the upper Fort Union aquifer, the lower Fort Union aquifer, and the Fox Hills-lower Hell Creek aquifer. Data used for wells, springs, seeps, and water quality in this report were compiled from the U.S. Geological Survey National Water Information System or from the North Dakota State Water Commission. An inventory of 16 wells was completed for sites within the boundaries of the park. In addition to well data, an inventory of 11 springs and seeps was completed. The groundwater-quality analysis had two objectives: (1) to characterize the groundwater chemistry in aquifers underlying the park and (2) to spatially map selected physical properties and chemical constituents of interest. Groundwater-quality data from the North Dakota State Water Commission were summarized, mapped, and used to characterize groundwater for each aquifer in the study area. Spatial concentration distribution maps were constructed for selected physical properties and chemical constituents using summary statistics and exceedances. Piper diagrams were used to classify and characterize groundwater for each aquifer. Future research to help fill data gaps in water resources information for Theodore Roosevelt National Park, including recommendations from previous studies, consists of the following: (1) evaluating the variability in discharge from springs and seeps in comparison to changes in precipitation or other recharge sources, (2) evaluating flow control measures for flowing artesian wells, (3) completing a water rights review, and (4) performing routine water-quality monitoring for wells and springs.

North Dakota↗
USGS1986

Reconnaissance of the water resources of the Hoh Indian Reservation and the Hoh River basin, Washington

Ground- and surface-water resources of the Hoh Indian Reservation and the Hoh River basin were studied from 1977 to 1980 under a cooperative agreement between the U.S. Geological Survey and the Hoh Indian Tribe. It was determined that moderate quantities of groundwater can be obtained from near-surface, river-deposited sands and gravels on the northeastern part of the reservation. Groundwater recharge (induced by pumping from a nearby oxbow lake) could supply numerous wells indefinitely with yields of 25 to 50 gallons/min. Geologic units in other areas of the reservation appear to have a low hydraulic conductivity and would yield little, if any, water to wells. At seven sites where housing construction is planned, soils were tested for infiltration rates and it was determined that soils are adequate for waste disposal in septic tanks and associated drain fields at those locations. Chalaat Creek, which flows across the reservation, provides water for salmon-rearing ponds. Except for moderately high bacteria concentrations (fecal coliform bacteria concentrations were as high as 33 colonies/100 mL), results of water quality analyses indicate no unusual or harmful concentrations of any chemical constituent or physical properties of the water that would restrict its use for most purposes. Chemical and bacteriological analyses of the Hoh River and its major tributaries downstream from the Olympic Park boundary revealed no unusual or harmful levels of constituents, with some minor exceptions. Small increases in concentrations of sodium, chloride, nitrite plus nitrate, and turbidity were measured in water samples collected from the Hoh River in a downstream direction. These increases are probably the result of natural weathering of rocks and soils in the basin. Fluvial-sediment transport of the Hoh River was 82,000 tons from March 1978 to February 1979 and 1,510,000 tons from March 1979 to February 1980. Mean annual transport was estimated to be 630 ,000 tons. About 60% of the sediment transported by the Hoh River originates from within the boundaries of the Olympic National Park, which includes about 70% of the area of the Hoh River drainage basin. (USGS)

Water-Resources Investigations Report↗
USGS1969

Geology and regional metamorphism of some high-grade cordierite gneisses, Front Range, Colorado

Cordierite is common in regional metamorphic gneisses of Precambrian age in the central part of the Front Range. It occurs in discontinuous stratigraphic units that are structurally a minor component, except locally, of the thick succession of biotite gneisses that comprise the widespread Idaho Springs Formation. The rocks have mineral assemblages, that are characteristic of the sillimanite grade of metamorphism. The cordierite occurs in three principal rock types: (1) potassic feldspar-bearing cordierite-garnet-sillimanite-biotite gneiss, (2) cordierite-biotite gneiss, and (3) cordierite-gedrite-biotite gneiss; each type contains several characteristic mineral assemblages. The rock types are gradational and overlap in areal distribution, and mainly owe their diversity in mineralogy to differences in bulk chemical composition. The field relations are consistent with an interpretation that the diverse cordierite rocks were derived from original sedimentary rocks, largely pelitic sediments. The potassic feldspar-bearing cordierite-garnet gneisses were formed from shales that contained more MgO and FeO than the more abundant sedimentary facies that yielded sillimanitic biotite gneisses. Cordierite-gedrite-biotite gneisses contain much aluminum, iron, and magnesium and little sodium and potassium as compared to the other biotite gneisses; they have an extremely low content of minor elements. Although their chemical compositions are unlike those of known modern sediments, the cordierite-gedrite gneisses are considered also to have been derived from sedimentary rocks. The physical properties and chemical compositions of the mineral phases vary somewhat from one rock type to another. Biotite varies systematically in composition, and the changes are closely related to rock type and thus to bulk composition; the MgO/FeO ratios range from 1.7 in the more mafic cordierite-gedrite rocks to 0.49 in potassic feldspar-bearing cordierite-garnet gneisses. Cordierite is magnesium-rich and intermediate in the range of composition of all analyzed cordierites (Leake, 1960); its MgO/FeO ratio is higher in the gedrite-bearing gneisses than in the potassic feldspar-bearing gneisses. The garnets consist dominantly of the almandine and pyrope molecules, and range from 64 to 75 percent almandine and from 14 to 27 pyrope. These crystals are zoned; their rims are slightly more ferrous and less magnesian than their cores. Both monoclinic and triclinic alkali feldspars coexist in the potassic feldspar-bearing cordierite-garnet gneisses. The potassic feldspars contain from 18 to 27 weight percent NaAlSi 3 O 8 . Plagioclase (oligoclase-andesine) is uncommon in the rocks. Gedrite has an MgO/FeO ratio ranging from 1 to 1.2. Associated minor minerals include iron oxides, andalusite, spinel and its alteration product högbomite, and corundum. The mineral assemblages can be correlated imperfectly with episodes of deformation and metamorphism. Relict staurolite and associated garnet occur locally as remnants of an assemblage formed early in regional metamorphism, presumably early in the first period of deformation. The dominant assemblage biotite-cordierite-garnet-magnetite-plagioclase-potassic feldspar-quartz-sillimanite and associated assemblages having fewer phases, were formed during period one and period two deformations, the principal episodes of regional dynamothermal metamorphism in the central part of the Front Range. A minor assemblage andalusite-biotite-magnetite-plagioclase-quartz was formed later, possibly coincident with a third period of deformation, largely cataclastic in effects, which was more local than the earlier deformations and metamorphism. Phase equilibria studies of the assemblage biotite-cordierite-garnet-magnetite-plagioclase-potassic feldspar-quartz-sillimanite and associated assemblages are interpreted to indicate that the cordierite assemblages approach a state of chemical equilibrium. The scatter of points in a distribution diagram can be interpreted in terms of at least two sets of equilibrium conditions that prevailed during the major plastic deformations. Other discrepancies indicating departure from a homogeneous equilibrium can be explained as a result of mosaic equilibrium involving limited diffusion of iron and magnesium for short distances. The mineral assemblages and the compositions of the ferromagnesian minerals in the cordierite rocks of this region are dependent primarily on the bulk composition of the rocks and variations in the mineral species that comprise the rocks and, to a lesser degree, on the grade of metamorphism. Biotite and cordierite are markedly more magnesian in the more mafic cordierite-gedrite-biotite gneiss than in the potassic feldspar-bearing cordierite-garnet-sillimanite-biotite gneiss. Associated microcline gneiss and biotite-sillimanite gneiss that contains muscovite as a primary stable mineral provides a means to define the metamorphic grade in the area of study. It is concluded from analyses of the assemblages with respect to theoretical phase relations in the system SiO 2 -Al 2 O 3 -Na 2 O-K 2 O-H 2 O that at least some of the rocks in the Central City-Nederland area are above the sillimanite-potassic feldspar isograd as defined by Evans and Guidotti (1966). In rocks of appropriate composition, muscovite is a stable phase in assemblages containing potassic feldspar and sillimanite. The cordierite assemblages and associated rocks are inferred to have formed in an environment having a load pressure of 3–5 kilobars (fluid pressure equaled load pressure) and a temperature somewhat in excess of 620° C.

Colorado↗
USGS2000

Regression analysis and real-time water-quality monitoring to estimate constituent concentrations, loads, and yields in the Little Arkansas River, south-central Kansas, 1995-99

Water from the Little Arkansas River is used as source water for artificial recharge to the Equus Beds aquifer, which provides water for the city of Wichita in south-central Kansas. To assess the quality of the source water, continuous in-stream water-quality monitors were installed at two U.S. Geological Survey stream-gaging stations to provide real-time measurement of specific conductance, pH, water temperature, dissolved oxygen, and turbidity in the Little Arkansas River. In addition, periodic water samples were collected manually and analyzed for selected constituents, including alkalinity, dissolved solids, total suspended solids, chloride, sulfate, atrazine, and fecal coliform bacteria. However, these periodic samples do not provide real-time data on which to base aquifer-recharge operational decisions to prevent degradation of the Equus Beds aquifer. Continuous and periodic monitoring enabled identification of seasonal trends in selected physical properties and chemical constituents and estimation of chemical mass transported in the Little Arkansas River. Identification of seasonal trends was especially important because high streamflows have a substantial effect on chemical loads and because concentration data from manually collected samples often were not available. Therefore, real-time water-quality monitoring of surrogates for the estimation of selected chemical constituents in streamflow can increase the accuracy of load and yield estimates and can decrease some manual data-collection activities. Regression equations, which were based on physical properties and analysis of water samples collected from 1995 through 1998 throughout 95 percent of the stream's flow duration, were developed to estimate alkalinity, dissolved solids, total suspended solids, chloride, sulfate, atrazine, and fecal coliform bacteria concentrations. Error was evaluated for the first year of data collection and each subsequent year, and a decrease in error was observed as the number of samples increased. Generally, 2 years of data (35 to 55 samples) collected throughout 90 to 95 percent of the stream's flow duration were sufficient to define the relation between a constituent and its surrogate(s). Relations and resulting equations were site specific. To test the regression equations developed from the first 3 years of data collection (1995-98), the equations were applied to the fourth year of data collection (1999) to calculate estimated constituent loads and the errors associated with these loads. Median relative percentage differences between measured constituent loads determined using the analysis of periodic, manual water samples and estimated constituent loads were less than 25 percent for alkalinity, dissolved solids, chloride, and sulfate. The percentage differences for total suspended solids, atrazine, and bacteria loads were more than 25 percent. Even for those constituents with large relative percentage differences between the measured and estimated loads, the estimation of constituent concentrations with regression analysis and real-time water-quality monitoring has numerous advantages over periodic manual sampling. The timely availability of bacteria and other constituent data may be important when considering recreation and the whole-body contact criteria established by the Kansas Department of Health and Environment for a specific water body. In addition, water suppliers would have timely information to use in adjusting water-treatment strategies; environmental changes could be assessed in time to prevent negative effects on fish or other aquatic life; and officials for the Equus Beds Ground-Water Recharge Demonstration project could use this information to prevent the possible degradation of the Equus Beds aquifer by choosing not to recharge when constituent concentrations in the source water are large. Constituent loads calculated from the regression equations may be useful for calculating total maximum daily loads (TMDL's), wh

Water-Resources Investigations Report↗
USGS1987

Chemical characteristics of water in the surficial aquifer system, Broward County, Florida

Water quality data was collected in 1981 and 1982 during the drilling of test holes at 27 sites throughout Broward County, Florida. Determinations were made for the following physical properties and chemical constituents: pH, alkalinity, specific conductance, major ions, selected nutrients and dissolved iron, aluminum, and manganese. Determinations for the trace elements-arsenic, barium, cadmium, chromium, lead, zinc, selenium, and mercury-were made at 14 wells. Water in the surficial aquifer system between the coastal ridge and the conservation areas is potable and usually is a calcium bicarbonate type for the first 140 ft or more below land surface. Between depths of 140 and 230 ft, groundwater generally grades into a mixed-ion water type. In some areas, diluted seawater occurs beneath the mixed water zone. Dissolved iron concentrations between the coastal ridge and the conservation areas are variable but generally exceed 1,000 micrograms/L. Beneath the conservation areas and the western edge of Broward County, groundwater in the first 100 ft below land surface generally is either a calcium bicarbonate type or a mixed-ion type. At depths between 100 and 200 ft, diluted residual seawater occurs, except along the far western edge of the county. Residual seawater is least diluted in the north. Dissolved iron concentrations generally are between 300 and 1 ,000 micrograms/L but increase to the east of the conservation areas. Other findings of the investigation include: (1) groundwater in some areas west of the coastal ridge probably would be suitable for most domestic, agricultural, and industrial uses if it were treated for carbonate hardness; (2) groundwater in much of Broward County is chemically altered by natural softening and magnesium enrichment (natural softening increases to the west and is very pronounced beneath the far western edge of the county); and (3) there is evidence of mineralized water from the conservation areas mixing with groundwater east of the levees. (Lantz-PTT)

Water-Resources Investigations Report↗
USGS2023

Use of physical blockers to control invasive red swamp crayfish in burrows

The red swamp crayfish Procambarus clarkii is native to the southeast United States but has successfully invaded nearly every continent around the world. Although physical, biological, and chemical controls are employed to reduce or eliminate populations in open-water systems, terrestrial burrows provide a potential refuge from aquatic control treatments. We conducted burrow trials to test whether two physical blocker treatments would kill P. clarkii in their burrows. Bentonite clay (a sealing agent) and expanding foam (an insulating sealant) were each applied to 37 crayfish burrows, and 36 burrows served as treatment controls (i.e., 110 total burrows). Burrows were excavated 48 hr after the application of the physical blockers to assess the status of crayfish in treated and control burrows. There was 74% mortality of crayfish in occupied burrows treated with bentonite clay, 62% in burrows treated with expanding foam, and 6% mortality in control burrows. We believe bentonite clay should continue to be field-tested; however, because expanding foam is toxic to aquatic organisms and is expected to persist in the environment, we do not believe it is a suitable physical blocker for the control of invasive crayfish in burrows. Bentonite clay applications likely will not need permits, will mitigate damage to banks and levees caused by burrowing crayfish, and can be used with other control agents such as pesticides. However, the use of physical blockers may be limited at field sites that have burrows with complex morphologies. We believe the use of bentonite clay to control invasive crayfish in terrestrial burrows will provide resource managers with an effective tool for their integrative pest management programs.

Management of Biological Invasions↗
USGS2007

Calculating background levels for ecological risk parameters in toxic harbor sediment

Establishing background levels for biological parameters is necessary in assessing the ecological risks from harbor sediment contaminated with toxic chemicals. For chemicals in sediment, the term contaminated is defined as having concentrations above background and significant human health or ecological risk levels. For biological parameters, a site could be considered contaminated if levels of the parameter are either more or less than the background level, depending on the specific parameter. Biological parameters can include tissue chemical concentrations in ecological receptors, bioassay responses, bioaccumulation levels, and benthic community metrics. Chemical parameters can include sediment concentrations of a variety of potentially toxic chemicals. Indirectly, contaminated harbor sediment can impact shellfish, fish, birds, and marine mammals, and human populations. This paper summarizes the methods used to define background levels for chemical and biological parameters from a survey of ecological risk investigations of marine harbor sediment at California Navy bases. Background levels for regional biological indices used to quantify ecological risks for benthic communities are also described. Generally, background stations are positioned in relatively clean areas exhibiting the same physical and general chemical characteristics as nearby areas with contaminated harbor sediment. The number of background stations and the number of sample replicates per background station depend on the statistical design of the sediment ecological risk investigation, developed through the data quality objective (DQO) process. Biological data from the background stations can be compared to data from a contaminated site by using minimum or maximum background levels or comparative statistics. In Navy ecological risk assessments (ERA's), calculated background levels and appropriate ecological risk screening criteria are used to identify sampling stations and sites with contaminated sediments.

California↗
USGS1994

Overview of environmental and hydrogeologic conditions at Barrow, Alaska

To assist the Federal Aviation Administration (FAA) in evaluating the potential effects of environmental contamination at their facility in Barrow, Alaska, a general assessment was made of the hydrologic system is the vicinity of the installation. The City of Barrow is located approximately 16 kilometers southwest of Point Barrow, the northernmost point in Alaska, and therefore lies within the region of continuous permafrost. Migration of surface or shallow- subsurface chemical releases in this environ- ment would be largely restricted by near-surface permafrost to surface water and the upper, suprapermafrost zone of the subsurface. In the arctic climate and tundra terrain of the Barrow area, this shallow environment has a limited capacity to attenuate the effects of either physical disturbances or chemical contamination and is therefore highly susceptible to degradation. Esatkuat Lagoon, the present drink- ing water supply for the City of Barrow, is located approximately 2 kilometers from the FAA facility. This lagoon is the only practical source of drinking water available to the City of Barrow because alternative sources of water in the area are (1) frozen throughout most of the year, (2) insufficient in volume, (3) of poor quality, or (4) too costly to develop and distribute.

Open-File Report↗
USGS2006

Data Delivery and Mapping Over the Web: National Water-Quality Assessment Data Warehouse

The U.S. Geological Survey began its National Water-Quality Assessment (NAWQA) Program in 1991, systematically collecting chemical, biological, and physical water-quality data from study units (basins) across the Nation. In 1999, the NAWQA Program developed a data warehouse to better facilitate national and regional analysis of data from 36 study units started in 1991 and 1994. Data from 15 study units started in 1997 were added to the warehouse in 2001. The warehouse currently contains and links the following data: -- Chemical concentrations in water, sediment, and aquatic-organism tissues and related quality-control data from the USGS National Water Information System (NWIS), -- Biological data for stream-habitat and ecological-community data on fish, algae, and benthic invertebrates, -- Site, well, and basin information associated with thousands of descriptive variables derived from spatial analysis, like land use, soil, and population density, and -- Daily streamflow and temperature information from NWIS for selected sampling sites.

Fact Sheet↗
USGS2012

Threats and stressors to the health of the ecosystems of Lakes Mead and Mohave: Chapter 6 in A synthesis of aquatic science for management of Lakes Mead and Mohave

Ecosystem impacts from visitor activities or natural environmental change are important concerns in all units of the National Park system. Possible impacts to aquatic ecosystems at Lake Mead National Recreation Area (LMNRA) are of particular concern because of the designation of Lakes Mead and Mohave as critical habitat for the federally listed endangered razorback sucker (Xyrauchen texanus), the significance of the sport fishery, and the regional importance of its habitats to more than 90 documented species of waterbirds. Potential threats to shoreline habitats are of concern not only for their ecosystem values but also for maintaining the recreational setting. Many areas adjacent to the shorelines of Lakes Mead and Mohave are designated wilderness areas. For purposes of this document, stressors are any chemical, biological, or physical agent that has a detrimental effect on aquatic ecosystems at the organism, population, or community level. Human-made stressors at Lakes Mead and Mohave include direct effects of recreation on the lakes, like boating and fishing, as well as indirect effects of activities away from the lakes, such as growing population and increasing urbanization. Common natural environmental stressors include extended changes in climate (precipitation or temperature), or the erosion, transport, and loading of chemical constituents in rocks and sediments to aquatic environments. Human activity also can exacerbate natural stressors in a variety of ways.

Circular↗
USGS2020

Passive sampling of groundwater wells for determination of water chemistry

Introduction Passive groundwater sampling is defined as the collection of a water sample from a well without the use of purging by a pump or retrieval by a bailer (Interstate Technology and Regulatory Council [ITRC], 2006; American Society for Testing and Materials [ASTM], 2014). No purging means that advection of water is not involved in collecting the water sample from the well. Passive samplers rely on diffusion as the primary process that drives their collection of chemical constituents. Diffusion is the transport of chemicals caused by the presence of a chemical gradient. Chemicals tend to move or diffuse from areas of higher concentration to areas of lower concentration to reach an average or equilibrium concentration. Passive sampling of groundwater relies on the ambient exchange of groundwater in the formation with water in the screened or open interval of a well. In this report, the term formation is used to describe all saturated hydrogeologic units that yield water to a well. If the well opening is unclogged and free of a film of deposits from physical turbidity or chemical precipitation, then the exchange of groundwater is likely adequate, and the water in the open interval will be representative of water in the formation. In some cases, the passive sample from the well opening can be more representative of groundwater from the formation than a sample collected by pumping if pumping induces mixing of water in the open interval with stagnant casing water that has undergone chemical alteration (Harte and others, 2018). In most cases, passive sampling will better represent the ambient groundwater chemistry flowing through the open interval of a well because pumping may capture water of different chemistry from downgradient or lateral areas that would not normally pass through the well. Three basic types of passive samplers are discussed in this report. The first type of passive sampler is the equilibrium-membrane type, which includes a semi-permeable membrane through which chemicals diffuse or permeate. Permeation is simply the process of water or chemicals moving through openings in the membrane. The authors contend that permeation is dominated by diffusion for many of the passive samplers discussed in this report. Some passive equilibrium-membrane-type samplers allow most types of chemical constituents through, whereas others allow the diffusion of only selected groups of chemicals. Once the chemical constituents are inside the membrane, they are retained by the equilibration of concentrations inside the sampler with those outside the sampler. The second type of passive sampler is an equilibrium-thief type, which has no semi-permeable membrane. Chemical constituents simply move through the openings in the body of the sampler either initially through advection and dispersion or over time primarily by diffusion. Chemical constituents reach equilibrium between the water in the sampler and the water in the well and are captured in the sampler when the sampler is closed. The third type of passive sampler is an accumulation-type sampler that contains sorptive media. Selected chemical constituents are sorbed onto the media that the sampler contains for later extraction and analysis. Although passive samplers have been available for more than 15 years (from present [2020]), their use by U.S. Geological Survey (USGS) hydrologists and hydrologic technicians to monitor groundwater quality largely has been limited to selected research studies. The authors believe that this may be the result of (1) a lack of exposure of most USGS personnel to passive samplers and the uses of these samplers and (2) the lack of a USGS-approved protocol for the proper use of these samplers by USGS personnel. This report is an effort to fill those two needs. The focus of this report is on hydraulic, hydrologic, and chemical considerations in the application of passive samplers and interpretation of groundwater chemistry results obtained using passive samplers in wells. This report describes the differences between purging and passive sampling methods in groundwater and explains how and why passive samplers work. The report points out the advantages and limitations of passive samplers in general and for each particular type of passive sampler. Important considerations to be taken into account prior to the use of passive samplers are discussed, such as defining the data-quality objectives, the water-quality constituents to be sampled, sample volumes required for analysis, well construction of the sampling network, and the geologic formations that will be sampled. Potential applications of passive samplers also are discussed, such as chemical-vertical profiling of wells. A general field protocol for the deployment, recovery, and sample collection using these devices is described, and some overall guidance for the practitioner with application examples is given. Comparison methods used to evaluate results from passive sampling versus purge sampling also are discussed.

Techniques and Methods↗
USGS2014

The future of nearshore processes research

The nearshore is the transition region between land and the continental shelf including (from onshore to offshore) coastal plains, wetlands, estuaries, coastal cliffs, dunes, beaches, surf zones (regions of wave breaking), and the inner shelf (Figure ES-1). Nearshore regions are vital to the national economy, security, commerce, and recreation. The nearshore is dynamically evolving, is often densely populated, and is under increasing threat from sea level rise, long-term erosion, extreme storms, and anthropogenic influences. Worldwide, almost one billion people live at elevations within 10 m of present sea level. Long-term erosion threatens communities, infrastructure, ecosystems, and habitat. Extreme storms can cause billions of dollars of damage. Degraded water quality impacts ecosystem and human health. Nearshore processes, the complex interactions between water, sediment, biota, and humans, must be understood and predicted to manage this often highly developed yet vulnerable nearshore environment. Over the past three decades, the understanding of nearshore processes has improved. However, societal needs are growing with increased coastal urbanization and threats of future climate change, and significant scientific challenges remain. To address these challenges, members of academia, industry, and federal agencies (USGS, USACE, NPS, NOAA, FEMA, ONR) met at the “The Past and Future of Nearshore Processes Research: Reflections on the Sallenger Years and a New Vision for the Future” workshop to develop a nearshore processes research vision where societal needs and science challenges intersect. The resulting vision is comprised of three broad research themes: Long-term coastal evolution due to natural and anthropogenic processes: As global climate change alters the rates of sea level rise and potentially storm patterns and coastal urbanization increases over the coming decades, an understanding of coastal evolution is critical. Improved knowledge of long-term morphological, ecological, and societal processes and their interactions will result in an improved ability to simulate coastal change. This will enable proactive solutions for resilient coasts and better guidance for reducing coastal vulnerability. Extreme Events: Flooding, erosion, and the subsequent recovery: Hurricane Sandy caused flooding and erosion along hundreds of miles of shoreline, flooded New York City, and impacted communities and infrastructure. Overall U.S. coastal extreme event related economic losses have increased substantially. Furthermore, climate change may cause an increase in coastal extreme events and rising sea levels could increase the occurrence of extreme events. Addressing this research theme will result in an improved understanding of the physical processes during extreme events, leading to improved models of flooding, erosion, and recovery. The resulting societal benefit will be more resilient coastal communities. The physical, biological and chemical processes impacting human and ecosystem health: Nearshore regions are used for recreation, tourism, and human habitation, and provide habitat and valuable ecosystem services. These areas must be sustained for future generations, however overall coastal water quality is declining due to microbial pathogens, fertilizers, pesticides, and heavy metal contamination, threatening ecosystem and human health. To ensure sustainable nearshore regions, predictive real-time water- and sediment-based based pollutant modeling capabilities must be developed, which requires expanding our knowledge of the physics, chemistry, and biology of the nearshore. The resulting societal benefits will include better beach safety, healthier ecosystems, and improved mitigation and regulatory policies. The scientists and engineers of the U.S. nearshore community are poised to make significant progress on these research themes, which have significant societal impact. The U.S. nearshore community, including academic, government, and industry colleagues, recommends multi-agency investment into a coordinated development of observational and modeling research infrastructure to address these themes, as discussed in the whitepaper. The observational infrastructure should include development of new sensors and methods, focused observational programs, and expanded nearshore observing systems. The modeling infrastructure should include improved process representation, better model coupling, incorporation of data assimilation techniques, and testing of real-time models. The observations will provide test beds to compare and improve models.

Report↗
USGS2015

Eelgrass habitat near Liberty Bay: Chapter 5

Seagrasses are a widespread type of marine flowering plants that grow in nearshore intertidal and subtidal zones. Seagrass beds are ecologically important because they affect physical, biological, and chemical characteristics of nearshore habitat, and they are sensitive to changes in coastal water quality (Stevenson and others, 1993; Koch, 2001; Martinez-Crego and others, 2008). Zostera marina, commonly known as eelgrass, is protected by a no-net-loss policy in Washington State where it may be used as spawning habitat by herring, a key prey species for salmon, seabirds, and marine mammals (Bargmann, 1998). Eelgrass forms broad meadows in shallow embayments or narrow fringes on open shorelines (Berry and others, 2003). Anthropogenic activities that increase turbidity, nutrient loading, and physical disturbance at the coast can result in dramatic seagrass decline (Ralph and others, 2006).

Washington↗