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USGS1985

Index of ground-water quality data for Florida

The Master Water Data Index of the U.S. Geological Survey contains records and information for 13,925 ground-water quality collection sites in Florida as follows: 2,180 active and 11,559 inactive well sites, and 39 active and 147 inactive spring sites. Ground-water quality data have been and are being collected at more sites in Florida than are other types of ground- and surface-water hydrologic data. Information available from the Master Water Data Index includes location (county, hydrologic unit, and latitude-longitude); reporting agency; agency identifying number; period and frequency of record; types of data (parameter sampled); and for wells, the principal aquifer sampled and well depth. This information may be retrieved, upon request, in a variety of formats. This report contains an index of the information available, not the actual water-quality data itself. The actual data may be obtained from the reporting agency that collected and stored the data. (USGS)

Open-File Report↗
USGS1985

Selected test-well data from the MX-missile siting study, Tooele, Juab, Millard, Beaver, and Iron Counties, Utah

This report contains well data collected from 1979 to 1983 in a part of the Great Basin in western Utah (fig. 1). The area is characterized by a series of generally north-trending mountain ranges separated by alluviumfilled basins that are partially filled with sedimentary deposits eroded from the adjacent mountains and lacustrine sediments deposited by Lake Bonneville. Most of the intermountain basins are elongated in the northward direction, but some are almost equidimensional. This report was prepared as part of the Great Basin Regional AquiferSystem Analysis (RASA) program. The report is intended to make well data from the MX-missile siting study readily available to water-resource managers and the general public. It includes well data obtained in areas for which little or no such data have been published previously. Well-drilling and well-completion data were compiled by Ertec, Inc. (formerly Fugro National, Inc.) under contract with the U. S. Air Force. Those data along with aquifer test data, geophysical logs, and drillers1 or geologists1 logs were obtained from Ertec, Inc. under an agreement with the U.S. Air Force. The authors thank the officials of both Ertec, Inc. and the U.S. Air Force for their helpful cooperation. The U.S. Geological Survey obtained accurate locations of the test wells (pi. 1) and accurate water-level measurements in those wells (table 1). Chemical analyses of water samples collected from several of the test wells drilled in the Sevier Desert have been published in a report by Enright and Holmes (1982, table 5). Test drilling for the MX-missile siting study consisted of two parts, the verification phase and the water-resources phase. The verification jhase was designed to obtain information necessary for the design and construction of the MX-basing system. Numerous small diameter wells were bored with depths ranging from 92 to 205 feet. Two-inch diameter JVC casing with the bottom 20 feet perforated was installed in each borehole. The water-resources phase was designed to determine ground-water availibility and to estimate the effects of ground-water withdrawals required for the construction of the MX-basing system. Six large-diameter production test wells were drilled along with associated small-diameter observation wells. Depths ranged from 310 to 1,399 feet. Lithologic logs for selected production test wells or associated observation wells are listed in table 2. Geophysical logs and aquifer test data are available in the files of the U. S. Geological Survey, as indicated in table 1.

Utah↗
USGS1986

Hydrologic data for the south-central area, Nebraska

Hydrologic data were compiled for the South-Central hydrogeology study, which covers an area of approximately 5,600 square miles in south-central Nebraska. Data pertain to the groundwater, surface water, climate, land use, and pumpage and precipitation at water use sites in the study area. Groundwater data include water level elevations from three mass measurements of wells and water quality information from 68 water quality sampling sites. Surface water data include average annual stream flows and average October through December streamflows at U.S. Geological Survey gaging stations, canal diversions, and seepage from canals and reservoirs. Climatic data include monthly precipitation records for eight weather stations and evaporation data from four reservoirs. Land use data were compiled for agricultural land uses, by county, from 1940 through 1981. Water use site data include water levels at each of 18 sites, soil information for those sites with complete precipitation and pumpage records, and precipitation and groundwater pumpage information for each site. (USGS)

Open-File Report↗
USGS1988

Hydrologic data for urban studies in the Austin metropolitan area, Texas, 1986

The Geological Survey, in cooperation with the Texas Department of Water resources, began hydrologic studies in the Austin urban area in 1954. In cooperation with the city of Austin, the program was expanded in 1975 to include additional streamflow and rainfall-gaging stations, and the collection of surface water-quality data. In 1978, the program was expanded to include a ground-water resources study of the South Austin metropolitan area in the Balcones fault zone. The objectives of the Austin urban hydrology study are as follows: To determine, on the basis of historical data and hydrologic analyses, the magnitude and frequency of flood peaks and flood volume. To determine the effect of urban development on flood peaks and volume. To determine the variations in water quality during different seasons and flow conditions in representative watersheds with various types of urban development. To quantitatively appraise the ground-water resources of the Edwards aquifer in hydraulic circulation with Barton Springs, the effect of urbanization on the quality and quantity of recharge and discharge, and the extent of contamination in the aquifer. This report presents the basic hydrologic data collected in the Austin urban area for the 1986 water year (Oct. 1, 1985 to Sept. 30, 1986). Additional explanations of terms related to streamflow, water quality, and other hydrologic data used in this report are defined in the U.S. Geological Survey annual report Water Resources Data for Texas, TX-85-3, 1986. Analyses of "Hydrologic data for urban studies in the Austin, Texas, metropolitan area" from 1975 to 1982 are presented in a report by Veenhuis and Gannett (1986). Two analyses were made to determine the effects of urbanization on flood peaks in streams in the Austin metropolitan area. The first analysis compares flood recurrence intervals of urban drainage basins to rural drainage basins. In the second analysis, data from one drainage basin in which considerable urban development occurred during the study period, were used. The data were analyzed for changes in rainfall-runoff and flood frequency relations due to urbanization.

Open-File Report↗
USGS1989

A general method for generating bathymetric data for hydrodynamic computer models

To generate water depth data from randomly distributed bathymetric data for numerical hydrodymamic models, raw input data from field surveys, water depth data digitized from nautical charts, or a combination of the two are sorted to given an ordered data set on which a search algorithm is used to isolate data for interpolation. Water depths at locations required by hydrodynamic models are interpolated from the bathymetric data base using linear or cubic shape functions used in the finite-element method. The bathymetric database organization and preprocessing, the search algorithm used in finding the bounding points for interpolation, the mathematics of the interpolation formulae, and the features of the automatic generation of water depths at hydrodynamic model grid points are included in the analysis. This report includes documentation of two computer programs which are used to: (1) organize the input bathymetric data; and (2) to interpolate depths for hydrodynamic models. An example of computer program operation is drawn from a realistic application to the San Francisco Bay estuarine system. (Author 's abstract)

Open-File Report↗
USGS1994

Documentation of a spatial data-base management system for monitoring pesticide application in Washington

The Pesticide-Application Data-Base Management System was created as a demonstration project and was tested with data submitted to the Washington State Department of Agriculture by pesticide applicators from a small geographic area. These data were entered into the Department's relational data-base system and uploaded into the system's ARC/INFO files. Locations for pesticide applica- tions are assigned within the Public Land Survey System grids, and ARC/INFO programs in the Pesticide-Application Data-Base Management System can subdivide each survey section into sixteen idealized quarter-quarter sections for display map grids. The system provides data retrieval and geographic information system plotting capabilities from a menu of seven basic retrieval options. Additionally, ARC/INFO coverages can be created from the retrieved data when required for particular applications. The Pesticide-Application Data-Base Management System, or the general principles used in the system, could be adapted to other applica- tions or to other states.

Open-File Report↗
USGS1993

Streamflow and water-quality data for Lake Purdy and its tributaries, Jefferson and Shelby Counties, Alabama, water years 1987-91

An investigation was begun in North Carolina in 1988 to: (1) quantify nutrient, sediment, and freshwater loadings in canals that collect drainage from cropland field ditches; (2) determine the effects of tide gates and flashboard risers on these loadings and on receiving-water quality; and (3) characterize the effects of drainage on the salinity regime of a tidal creek. Data were collected in three canals in Hyde County, three canals in Beaufort County, and in Campbell Creek, which receives drainage directly from two of the Beaufort County canals. Water-control structures were placed on two of the six canals near the beginning of the investigation. Following about 2 years of data collection, control structures were placed on the remaining four canals. Hydrologic and water-quality data are presented for each of the study sites for the period of October 1990 through May 1992. Data presented in this report cover the second phase of the investigation after the installation of water-control structures in the six drainage canals. Following a description of the study sites and data-collection methods, data are presented for five of the drainage canals and Campbell Creek. Data collection was discontinued at one of the Beaufort County sites after the first phase of the investigation. The data collected include: (1) daily values of accumulated precipitation; (2) water-level statistics; (3) daily mean values of discharge in the canals; (4) biweekly water-quality measurements and sample analyses; (5) storm-event water-quality measurements and sample analyses; (6) continuous records of specific conductance in the canals; (7) vertical profiles of salinity in Campbell Creek; and (8) daily mean values of salinity at five sites in Campbell Creek.

Open-File Report↗
USGS1994

Compilation of selected hydrologic data, through water year 1992, Black Hills Hydrology Study, western South Dakota

This report presents water-level, water-quailty, and springflow data that have been collected or compiled, through water year 1992, for the Black Hills Hydrology Study. This study is a long-term cooperative effort between the U.S. Geological Survey, the South Dakota Department of Environmental and Natural Resources, and the West Dakota Water Development District (which represents various local and county cooperators). Water-level data are presented for 32 observation wells and 2 cave sites in the Black Hills area of western South Dakota. The wells are part of a network of observation wells maintained by the South Dakota Department of Environment and Natural Resources and are completed in various bedrock formations that are utilized as aquifers in the Black Hills area. Both cave sites are located within outcrops of the Madison Limestone. Data presented include site descriptions, hydrographs, and tabular data. Water- quality data are presented for 12 surface-water sites and 5 ground-water sites. Data presented include field parameters, bacteria counts, and concentrations of common ions, solids, nutrients, trace elements, radiometrics, cyanide, phenols, dissolved organic carbon, and suspended sediment. Spring data are presented for 83 springs and 21 stream reaches with significant springflow components. Data presented include site information, discharge, and field water-quality parameters including temperature, specific conductance, dissolved oxygen, and pH.

Open-File Report↗
USGS1994

Global energy and water cycle experiment (GEWEX) continental-scale international project (GCIP); reference data sets CD-ROM

The data sets on this compact disc are a compilation of several geographic reference data sets of interest to the global-change research community. The data sets were chosen with input from the Global Energy and Water Cycle Experiment (GEWEX) Continental-Scale International Project (GCIP) Data Committee and the GCIP Hydrometeorology and Atmospheric Subpanels. The data sets include: locations and periods of record for stream gages, reservoir gages, and meteorological stations; a 500-meter-resolution digital elevation model; grid-node locations for the Eta numerical weather-prediction model; and digital map data sets of geology, land use, streams, large reservoirs, average annual runoff, average annual precipitation, average annual temperature, average annual heating and cooling degree days, hydrologic units, and state and county boundaries. Also included are digital index maps for LANDSAT scenes, and for the U.S. Geological Survey 1:250,000, 1:100,000, and 1:24,000-scale map series. Most of the data sets cover the conterminous United States; the digital elevation model also includes part of southern Canada. The stream and reservoir gage and meteorological station files cover all states having area within the Mississippi River Basin plus that part of the Mississippi River Basin lying within Canada. Several data-base retrievals were processed by state, therefore many sites outside the Mississippi River Basin are included.

Open-File Report↗
USGS1995

Reference manual for data base on Nevada water-rights permits

The U.S. Geological Survey and Nevada Division of Water Resources have cooperatively developed and implemented a data-base system for managing water-rights permit information for the State of Nevada. The Water-Rights Permit data base is part of an integrated system of computer data bases using the Ingres Relational Data-Base Manage-ment System, which allows efficient storage and access to water information from the State Engineer's office. The data base contains a main table, three ancillary tables, and five lookup tables, as well as a menu-driven system for entering, updating, and reporting on the data. This reference guide outlines the general functions of the system and provides a brief description of data tables and data-entry screens.

Open-File Report↗
USGS1995

Cerro Prieto geothermal field, Mexico; chemical analyses and other data for 58 samples collected in 1977-1979

This report releases the results of selected chemical analyses by the USGS of fluids collected from geothennal power production wells at the Cerro Prieto Geothennal Field, Mexico. Cerro Prieto, the world's largest producing hot-water geothennal field, is located 32 km southeast of Mexicali, Baja California. Comision Federal de Electricidad de Mexico (CFE) gave permission for, and assisted in, sample collection. Data collection and reported analyses was made by the U.S. Geological Survey. Data collected in 1977 and 1978 where published previously by Ball and Jenne (1983) which was about half the data given here. This report also includes samples collected in 1979 which were not previously released. These activities, including this data release, are supported by the U.S. Department of Energy. Analyses given in the following section were made by James W. Ball and E.A. Jenne. The data have been reviewed with the assistance of Cathy Janik, USGS, Menlo Park. Some, but not all, details from Ball and Jenne (1983) concerning collection, and preservation and analytical procedures are repeated here. Nehring and Trusdell (1977) also provide an outline of some of the issues involved in the difficult task of collecting samples from geothermal wells. The initial intent of the study was to provide basic data for use in determining how these fluids should be managed either in disposal or in reinjection. Some of the hot, corrosive brines were separated as two-phase (water and steam) samples under pressure using a coiled condenser tube submerged in an ice/water mixture (called "condensed" samples). It is not known if these were total flow samples. Other samples were collected from the brine sampling valve of the separators (called "flashed" samples). Analyses given in the following section area sorted by (1) well number, (2) date, and (3) sample type(s). Analysis was by a Spectraspan III d.c. argon plasma emission spectrometer with a Spectraject III torch (Ball and Jenne, 1983). Elements were determined in two groups using interchangeable cassettes. Group one included B, Mn, Cu, Zn, Si, Zr, Be, Mn, Sr, Ti, Ca, Fe, Ba, K, Na, Rb, and Al. Group two included As, Se, Bi, Zn, Cd, Sb, Cu, Ni, Hg, Mo, Co, Cr, Fe, V, Tl, Li, and Pb. Ball and Jenne (1983) noted that analysis of B, Ca, Mg, Ba, and Sr generally gave precise results. Movement of the plasma or grating was observed to affect sensitivity over short time periods even while the instrument was carefully standardized and optimized. Sensitivity was also a function of sample concentration. All samples at the time of analysis contained a white precipitate (perhaps colloidal silica) thus the reported concentrations may not accurately represent the concentrations present at the time of collection (Ball and Jenne, 1983). Additional details about specific elements are given in the section on "Evaluation of data" (Bliss, this volume) following the data table.

Open-File Report↗
USGS1995

Integrating multisource land use and land cover data

As part of the U.S. Geological Survey's (USGS) land use and land cover (LULC) program, the USGS in cooperation with the Environmental Systems Research Institute (ESRI) is collecting and integrating LULC data for a standard USGS 1:100,000-scale product. The LULC data collection techniques include interpreting spectrally clustered Landsat Thematic Mapper (TM) images; interpreting 1-meter resolution digital panchromatic orthophoto images; and, for comparison, aggregating locally available large-scale digital data of urban areas. The area selected is the Vancouver, WA-OR quadrangle, which has a mix of urban, rural agriculture, and forest land. Anticipated products include an integrated LULC prototype data set in a standard classification scheme referenced to the USGS digital line graph (DLG) data of the area and prototype software to develop digital LULC data sets. This project will evaluate a draft standard LULC classification system developed by the USGS for use with various source material and collection techniques. Federal, State, and local governments, and private sector groups will have an opportunity to evaluate the resulting prototype software and data sets and to provide recommendations. It is anticipated that this joint research endeavor will increase future collaboration among interested organizations, public and private, for LULC data collection using common standards and tools.

Open-File Report↗
USGS1996

Hydrologic data for the East Poplar oil field, Fort Peck Indian Reservation, Northeastern Montana

This report presents selected hydrologic data for the East Poplar oil field, located in the south-central part of the Fort Peck Indian Reservation in northeastern Montana. Data about the occurrence, quantity, and quality of ground and surface water are presented in tabular form. The tables contain records of privately owned wells (active and abandoned), monitoring wells installed by the U.S. Geological Survey and Montana Bureau of Mines and Geology, oil wells, and brine-injection wells; lithologic descriptions of drill cuttings and well-completion data from monitoring wells; data from two aquifer tests conducted in Quaternary alluvial and glacial deposits; chemical quality of ground water; and information on the quantity and chemical quality of surface water. Records of electromagnetic geophysical measurements collected throughout an area of about 20 square miles of the study area are compiled and included on a floppy disk. Illustrations in this report contain information about study area location, site- numbering system, general physical and cultural features, and construction of monitoring wells installed by the U.S. Geological Survey. plate-sized map presents additional information about privately owned wells, monitoring wells, oil wells, brine-injections wells, surface-water data-collection sites, and area of electromagnetic data collection. The data presented in this report provide a base with which to better define and interpret the occurrence, quantity, and quality of ground and surface water in the vicinity of the Poplar River Valley in the south-central part of the Fort Peck Indian Reservation. The data can be used to help delineate the occurrence of brine and saline water in Quaternary alluvial and glacial deposits in the East Poplar oil field.

Open-File Report↗
USGS1996

Bridge-Scour Data Management System user's manual

The Bridge-Scour Data Management System (BSDMS) supports preparation, compilation, and analysis of bridge-scour data. The BSDMS provides interactive storage, retrieval, selection, editing, and display of bridge-scour data sets. Bridge-scour data sets include more than 200 site and measurement attributes of the channel geometry, flow hydraulics, hydrology, sediment, geomorphic-setting, location, and bridge specifications. This user's manual provides a general overview of the structure and organization of BSDMS data sets and detailed instructions to operate the program. Attributes stored by the BSDMS are described along with an illustration of the input screen where the attribute can be entered or edited. Measured scour depths can be compared with scour depths predicted by selected published equations using the BSDMS. The selected published equations available in the computational portion of the BSDMS are described. This manual is written for BSDMS, version 2.0. The data base will facilitate: (1) developing improved estimators of scour for specific regions or conditions; (2) describing scour processes; and (3) reducing risk from scour at bridges. BSDMS is available in DOS and UNIX versions. The program was written to be portable and, therefore, can be used on multiple computer platforms. Installation procedures depend on the computer platform, and specific installation instructions are distributed with the software. Sample data files and data sets of 384 pier-scour measurements from 56 bridges in 14 States are also distributed with the software.

Open-File Report↗
USGS1996

Statistical and descriptive summaries of water-resources data for the Cannonball River basin, North Dakota and South Dakota

Existing hydrologic data and information for the Cannonball River Basin were compiled by the U.S. Geological Survey in cooperation with the Bureau of Reclamation. This report presents a summary of surface-water quality and streamflow data, ground-water quality data, ground-water level data, water-use data, and other information compiled from the U.S. Geological Survey, Bureau of Reclamation, North Dakota Game and Fish Department, North Dakota Department of Health, North Dakota Parks and Recreation Department, North Dakota State Water Commission, and Standing Rock Sioux Tribe data bases. The data are summarized statistically or descriptively, depending on the amount or nature of the data.

Open-File Report↗
USGS1997

Air temperature and precipitation data, Gulkana Glacier, Alaska, 1968-96

Daily, monthly, and annual average air temperature and precipitation-catch data were recorded at Gulkana Glacier basin, Alaska, between October 1967 and September 1996. The data set is important because it provides long-term climate information from the highest year-round climatological recording site in Alaska. The daily air temperature data set is 96 percent complete. The daily precipitation data set is 83 percent complete; precipitation data for 1993-96 are missing. Annual data summaries are calculated for each hydrologic year, October 1 through September 30, for years that have 12 months of data. Monthly precipitation-catch and average air temperature summaries are calculated for months with nine or fewer daily records missing. The average annual air temperature recorded at the site from hydrologic year 1968 through 1996 was -4.1 degrees Celsius. The coldest recorded year was 1972 with an average annual temperature of -6.7 degrees Celsius. The warmest year was 1981 with an average annual temperature of -2.6 degrees Celsius. January 1971 was the coldest month with an average temperature of -20.8 degrees Celsius. July 1989 was the warmest month with an average temperature of 8.7 degrees Celsius. January 17, 1971, was the coldest day with an average temperature of -35.0 degrees Celsius. June 15, 1969, was the warmest day with an average temperature of 16.4 degrees Celsius. The average annual precipitation catch recorded at the site from hydrologic year 1968 through 1992 was 1,020 millimeters. The highest annual precipitation catch recorded was 1,572 millimeters in 1981; the lowest was 555 millimeters in 1969. The highest recorded monthly precipitation catch was 448 millimeters in July 1981 and in several different months no precipitation was recorded. The highest daily precipitation catch was 99 millimeters on September 12, 1972, and on many different dates no precipitation was recorded. Because of low gage-catch efficiency the reported annual precipitation-catch data are estimated to represent about 62 percent of the actual annual basin precipitation. Snowfall is the dominant form of precipitation on the glacier from September through mid-June.

Open-File Report↗
USGS1999

Geologic and hydrologic data for the municipal solid waste landfill facility, U.S. Army Air Defense Artillery Center and Fort Bliss, El Paso County, Texas

Geologic and hydrologic data for the Municipal Solid Waste Landfill Facility on the U.S. Army Air Defense Artillery Center and Fort Bliss in El Paso County, Texas, were collected by the U.S. Geological Survey in cooperation with the U.S. Department of the Army. The 106.03-acre landfill has been in operation since January 1974. The landfill contains household refuse, Post solid wastes, bulky items, grass and tree trimmings from family housing, refuse from litter cans, construction debris, classified waste (dry), dead animals, asbestos, and empty oil cans. The depth of the filled areas is about 30 feet and the cover, consisting of locally derived material, is 2 to 3 feet thick. Geologic and hydrologic data were collected at or adjacent to the landfill during (1) drilling of 10 30- to 31-foot boreholes that were completed with gas-monitoring probes, (2) drilling of a 59-foot borehole, (3) drilling of a 355-foot borehole that was completed as a ground-water monitoring well, and (4) in situ measurements made on the landfill cover. After completion, the gas- monitoring probes were monitored on a quarterly basis (1 year total) for gases generated by the landfill. Water samples were collected from the ground-water monitoring well for chemical analysis. Data collection is divided into two elements: geologic data and hydrologic data. Geologic data include lithologic descriptions of cores and cuttings, geophysical logs, soil- gas and ambient-air analyses, and chemical analyses of soil. Hydrologic data include physical properties, total organic carbon, and pH of soil and sediment samples; soil-water chloride and soil-moisture analyses; physical properties of the landfill cover; measurements of depth to ground water; and ground-water chemical analyses. Interpretation of data is not included in this report.

Texas↗
USGS2004

Chemical Data for Detailed Studies of Irrigation Drainage in the Salton Sea Area, California, 1995?2001

The primary purpose of this report is to present all chemical data from the Salton Sea area collected by the U.S. Geological Survey between 1995 and 2001. The data were collected primarily for the Department of the Interior's National Irrigation Water Quality Program (NIWQP). The report also contains a brief summary and citation to investigations done for the NIWQP between 1992 and 1995. The NIWQP began studies in the Salton Sea area in 1986 to evaluate effects on the environment from potential toxins, especially selenium, in irrigation-induced drainage. This data report is a companion to several reports published from the earlier studies and to interpretive publications that make use of historical and recent data from this area. Data reported herein are from five collection studies. Water, bottom material, and suspended sediment collected in 1995-96 from the New River, the lower Colorado River, and the All-American Canal were analyzed for elements, semi-volatile (extractable) organic compounds, and organochlorine compounds. Sufficient suspended sediment for chemical analyses was obtained by tangential-flow filtration. A grab sample of surficial bottom sediment collected from near the deepest part of the Salton Sea in 1996 was analyzed for 44 elements and organic and inorganic carbon. High selenium concentration confirmed the effective transfer (sequestration) of selenium into the bottom sediment. Similar grab samples were collected 2 years later (1998) from 11 locations in the Salton Sea and analyzed for elements, as before, and also for nutrients, organochlorine compounds, and polycyclic aromatic hydrocarbons. Nutrients were measured in bottom water, and water-column profiles were obtained for pH, conductance, temperature, and dissolved oxygen. Element and nutrient concentrations were obtained in 1999 from cores at 2 of the above 11 sites, in the north subbasin of the Salton Sea. The most-recent study reported herein was done in 2001 and contains element data on suspended material isolated by continuous-flow centrifugation on samples collected in transects extending out from the Whitewater, the Alamo, and the New Rivers into the Salton Sea. Chemical data on suspended sediment and bottom material from tributory rivers and the Salton Sea itself show that many insoluble constituents, including selenium and DDE, are concentrated in the fine-grained, organic- and carbonate-rich bottom sediment from deep areas near the center of the Salton Sea. Data also show that selenium and arsenic are markedly enriched in seston (plankton, partially-degraded algal detritus, and mineral matter that compose suspended particulates in the lake) collected just below the water surface in the Salton Sea. This result indicates that bio-concentration in primary producers in the water column provides an important pathway whereby high selenium residues accumulate in fish and fish-eating birds at the Salton Sea.

Scientific Investigations Report↗