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USGS2006

Summary of Environmental Monitoring and Assessment Program (EMAP) activities in South Dakota, 2000–2004

The U.S. Environmental Protection Agency (USEPA) initiated data-collection activities for the Environmental Monitoring and Assessment Program-West (EMAP-West) in South Dakota during 2000. The objectives of the study were to develop the monitoring tools necessary to produce unbiased estimates of the ecological condition of surface waters across a large geographic area of the western United States, and to demonstrate the effectiveness of those tools in a large-scale assessment. In 2001, the U.S. Geological Survey (USGS) and the South Dakota Department of Game, Fish and Parks (GF&P) established a cooperative agreement and assumed responsibility for completing the remaining assessments for the perennial, wadable streams of the EMAP-West in the State. Stream assessment sites were divided into two broad categories-the first category of sites was randomly selected and assigned by the USEPA for South Dakota. The second category consisted of sites that were specifically selected because they appeared to have reasonable potential for representing the best available physical, chemical, and biological conditions in the State. These sites comprise the second category of assessment sites and were called 'reference' sites and were selected following a detailed evaluation process. Candidate reference site data will serve as a standard or benchmark for assessing the overall ecological condition of the randomly selected sites. During 2000, the USEPA completed 22 statewide stream assessments in South Dakota. During 2001-2003, the USGS and GF&P completed another 42 stream assessments bringing the total of randomly selected stream assessments within South Dakota to 64. In addition, 18 repeat assessments designed to meet established quality-assurance/quality-control requirements were completed at 12 of these 64 sites. During 2002-2004, the USGS in cooperation with GF&P completed stream assessments at 45 candidate reference sites. Thus, 109 sites had stream assessments completed in South Dakota for EMAP-West (2000-2004). Relatively early in the EMAP-West stream-assessment process, it became apparent that for some streams in south-central South Dakota, in-stream conditions varied considerably over relatively short distances of only a few miles. These changes appeared to be a result of geomorphic changes associated with changes in the underlying geology. For these streams, moving stream assessment sites short distances upstream or downstream had the potential to provide substantially different bioassessment data. In order to obtain a better understanding of how geology influences stream conditions, two streams located in south-central South Dakota were chosen for multiple stream sampling at sites located along their longitudinal profile at points where notable changes in geomorphology were observed. Subsequently, three sites on Bear-in-the-Lodge Creek and three sites on Black Pipe Creek were selected for multiple stream sampling using EMAP-West protocols so that more could be learned about geologic influences on stream conditions. Values for dissolved oxygen and specific conductance generally increased from upstream to downstream locations on Bear-in-the-Lodge Creek. Values for pH and water temperature generally decreased from upstream to downstream locations. Decreasing water temperature could be indicative of ground-water inflows. Values for dissolved oxygen, pH, and water temperature generally increased from upstream to downstream locations on Black Pipe Creek. The increase in temperature at the lower sites is a result of less dense riparian cover, and the warmer water also could account for the lower concentrations of dissolved oxygen found in the lower reaches of Black Pipe Creek. Values for specific conductance were more than three times greater at the lower site (1,342 microsiemens per centimeter (?S/cm)) than at the upper site (434 ?S/cm). The increase probably occurs when the stream transitions from contacting the underlying Ar

South Dakota↗

USGS2010

Relation of urbanization to stream habitat and geomorphic characteristics in nine metropolitan areas of the United States

The relation of urbanization to stream habitat and geomorphic characteristics was examined collectively and individually for nine metropolitan areas of the United States?Portland, Oregon; Salt Lake City, Utah; Denver, Colorado; Dallas?Forth Worth, Texas; Milwaukee?Green Bay, Wisconsin; Birmingham, Alabama; Atlanta, Georgia; Raleigh, North Carolina; and Boston, Massachusetts. The study was part of a larger study conducted by the U.S. Geological Survey from 1999 to 2004 to examine the effects of urbanization on the physical, chemical, and biological components of stream ecosystems. The objectives of the current study were to determine how stream habitat and geomorphic characteristics relate to different aspects of urbanization across a variety of diverse environmental settings and spatial scales. A space-for-time rural-to-urban land-cover gradient approach was used. Reach-scale habitat data and geomorphic characteristic data were collected once during low flow and included indicators of potential habitat degradation such as measures of channel geometry and hydraulics, streambed substrate, low-flow reach volume (an estimate of base-flow conditions), habitat complexity, and riparian/bank conditions. Hydrologic metrics included in the analyses were those expected to be altered by increases in impervious surfaces, such as high-flow frequency and duration, flashiness, and low-flow duration. Other natural and human features, such as reach-scale channel engineering, geologic setting, and slope, were quantified to identify their possible confounding influences on habitat relations with watershed-scale urbanization indicators. Habitat and geomorphic characteristics were compared to several watershed-scale indicators of urbanization, natural landscape characteristics, and hydrologic metrics by use of correlation analyses and stepwise linear regression. Habitat and geomorphic characteristics were related to percentages of impervious surfaces only in some metropolitan areas and environmental settings. The relations between watershed-scale indicators of urbanization and stream habitat depended on physiography and climate, hydrology, pre-urban channel alterations, reach-scale slope and presence of bedrock, and amount of bank stabilization and grade control. Channels increased in size with increasing percentages of impervious surfaces in southeastern and midwestern metropolitan areas regardless of whether the pre-existing land use was forest or agriculture. The amount of enlargement depended on annual precipitation and frequency of high-flow events. The lack of a relation between channel enlargement and increasing impervious surfaces in other metropolitan areas was thought to be confounded by pre-urbanization hydrologic and channel alterations. Direct relations of channel shape and streambed substrate to urbanization were variable or lacking, probably because the type, amount, and source of sediment are dependent on the phase of urbanization. Reach-scale slope also was important for determining variations in streambed substrate and habitat complexity (percentage of riffles and runs). Urbanization-associated changes in reach-scale riparian vegetation varied geographically, partially depending on pre-existing riparian vegetation characteristics. Bank erosion increased in Milwaukee?Green Bay and Boston urban streams, and bank erosion also increased with an increase in a streamflow flashiness index. However, potential relations likely were confounded by the frequent use of channel stabilization and bank protection in urban settings. Low-flow reach volume did not decrease with increasing urbanization, but instead was related to natural landscape characteristics and possibly other unmeasured factors. The presence of intermittent bedrock in some sampled reaches likely limited some geomorphic responses to urbanization, such as channel bed erosion. Results from this study emphasize the importance of including a wide range of landscape variables at m

Scientific Investigations Report↗

USGS2011

Proceedings of the Fourth Interagency Conference on Research in the Watersheds—Observing, Studying, and Managing for Change

These proceedings contain the abstracts, manuscripts, and posters of presentations given at the Fourth Interagency Conference on Research in the Watersheds—Observing, Studying, and Managing for Change, held at the Westmark Hotel in Fairbanks, Alaska, September 26–30, 2011. The conference was jointly hosted by the Bureau of Land Management and the National Park Service. Watersheds face resource impacts driven by accelerated change related to land use, population, and climate. About every three years a conference is held to bring together watershed researchers, observers, and managers to share scientific advances and management strategies. This year, the Fourth ICRW took a wider perspective on watershed science and examined some pressing issues of watershed science and management in our largest and perhaps most vulnerable state, Alaska. The purpose of the conference was to better understand the processes driving change and help managers incorporate societal needs and scientific uncertainty in the management of natural resources. The conference echoed similar themes to the last, highlighting the challenges of managing watersheds based on available science when considerably uncertainty remains regarding the hypothesized relationships between observed environmental changes and their ultimate effects. For example, while the scientific case for anthropogenic climate change has been well presented, confirming possible cause and effect relationships between climatic change and physical and ecological impacts in highly variable, natural systems continues to represent a scientific challenge. This goal becomes even more difficult when superimposed upon a long history of natural resource and land management practices that have fundamentally changed the physical, chemical and biological processes important in maintaining naturally functioning ecosystems. Designing and implementing studies to better understand watersheds and clearly communicating the findings to decisionmakers will be the primary challenge for natural resource scientists and managers into the foreseeable future.

Scientific Investigations Report↗

USGS2012

Linking urbanization to the Biological Condition Gradient (BCG) for stream ecosystems in the Northeastern United States using a Bayesian network approach

Urban development alters important physical, chemical, and biological processes that define urban stream ecosystems. An approach was developed for quantifying the effects of these processes on aquatic biota, and then linking those effects to endpoints that can be used for environmental management. These complex, interacting systems are challenging to model from a scientific standpoint. A desirable model clearly shows the system, simulates the interactions, and ultimately predicts results of management actions. Traditional regression techniques that calculate empirical relations between pairs of environmental factors do not capture the interconnected web of multiple stressors, but urban development effects are not yet understood at the detailed scales required to make mechanistic modeling approaches feasible. Therefore, in contrast to a fully deterministic or fully statistical modeling approach, a Bayesian network model provides a hybrid approach that can be used to represent known general associations between variables while acknowledging uncertainty in predicted outcomes. It does so by quantifying an expert-elicited network of probabilistic relations between variables. Advantages of this modeling approach include (1) flexibility in accommodating many model specifications and information types; (2) efficiency in storing and manipulating complex information, and to parameterize; and (3) transparency in describing the relations using nodes and arrows and in describing uncertainties with discrete probability distributions for each variable. In realization of the aforementioned advantages, a Bayesian network model was constructed to characterize the effect of urban development on aquatic macroinvertebrate stream communities through three simultaneous, interacting ecological pathways affecting stream hydrology, habitat, and water quality across watersheds in the Northeastern United States. This model incorporates both empirical data and expert knowledge to calculate the probabilities of attaining desired aquatic ecosystem conditions under different urban stress levels, environmental conditions, and management options. Ecosystem conditions are characterized in terms of standardized Biological Condition Gradient (BCG) management endpoints. This approach to evaluating urban development-induced perturbations in watersheds integrates statistical and mechanistic perspectives, different information sources, and several ecological processes into a comprehensive description of the system that can be used to support decision making. The completed model can be used to infer which management actions would lead to the highest likelihood of desired BCG tier achievement. For example, if best management practices (BMP) were implemented in a highly urbanized watershed to reduce flashiness to medium levels and specific conductance to low levels, the stream would have a 70-percent chance of achieving BCG Tier 3 or better, relative to a 24-percent achievement likelihood for unmanaged high urban land cover. Results are reported probabilistically to account for modeling uncertainty that is inherent in sources such as natural variability and model simplification error.

Scientific Investigations Report↗

USGS2012

Methods to characterize environmental settings of stream and groundwater sampling sites for National Water-Quality Assessment

Characterization of natural and anthropogenic features that define the environmental settings of sampling sites for streams and groundwater, including drainage basins and groundwater study areas, is an essential component of water-quality and ecological investigations being conducted as part of the U.S. Geological Survey's National Water-Quality Assessment program. Quantitative characterization of environmental settings, combined with physical, chemical, and biological data collected at sampling sites, contributes to understanding the status of, and influences on, water-quality and ecological conditions. To support studies for the National Water-Quality Assessment program, a geographic information system (GIS) was used to develop a standard set of methods to consistently characterize the sites, drainage basins, and groundwater study areas across the nation. This report describes three methods used for characterization-simple overlay, area-weighted areal interpolation, and land-cover-weighted areal interpolation-and their appropriate applications to geographic analyses that have different objectives and data constraints. In addition, this document records the GIS thematic datasets that are used for the Program's national design and data analyses.

Scientific Investigations Report↗

USGS2016

Vulnerabilities of national parks in the American Midwest to climate and land use changes

Many national parks in the American Midwest are surrounded by agricultural or urban areas or are in highly fragmented or rapidly changing landscapes. An environmental stressor is a physical, chemical, or biological condition that affects the functioning or productivity of species or ecosystems. Climate change is just one of many stressors on park natural resources; others include urbanization, land use change, air and water pollution, and so on. Understanding and comparing the relative vulnerability of a suite of parks to projected climate and land use changes is important for region-wide planning. A vulnerability assessment of 60 units in the 13-state U.S. National Park Service Midwestern administrative region to climate and land use change used existing data from multiple sources. Assessment included three components: individual park exposure (5 metrics), sensitivity (5 metrics), and constraints to adaptive capacity (8 metrics) under 2 future climate scenarios. The three components were combined into an overall vulnerability score. Metrics were measures of existing or projected conditions within park boundaries, within 10-kilometer buffers surrounding parks, and within ecoregions that contain or intersect them. Data were normalized within the range of values for all assessed parks, resulting in high, medium, and low relative rankings for exposure, sensitivity, constraints to adaptive capacity, and overall vulnerability. Results are consistent with assessments regarding patterns and rates of climate change nationwide but provide greater detail and relative risk for Midwestern parks. Park overall relative vulnerability did not differ between climate scenarios. Rankings for exposure, sensitivity, and constraints to adaptive capacity varied geographically and indicate regional conservation planning opportunities. The most important stressors for the most vulnerable Midwestern parks are those related to sensitivity (intrinsic characteristics of the park) and constraints on adaptive capacity (characteristics of the surrounding landscape) rather than exposure to external forces, including climate change. Output will allow individual park managers to understand which metrics weigh most heavily in the overall vulnerability of their park and can be used for region-wide responses and resource allocation for adaptation efforts.

Arkansas, Illinois, Indiana, Iowa, Kansas, Michiga↗

USGS2016

Sediment oxygen demand in eastern Kansas streams, 2014 and 2015

Dissolved oxygen concentrations in streams are affected by physical, chemical, and biological factors in the water column and streambed, and are an important factor for the survival of aquatic organisms. Sediment oxygen demand (SOD) rates in Kansas streams are not well understood. During 2014 and 2015, the U.S. Geological Survey, in cooperation with the Kansas Department of Health and Environment, measured SOD at eight stream sites in eastern Kansas to quantify SOD rates and variability with respect to season, land use, and bottom-sediment characteristics. Sediment oxygen demand rates (SOD T ) ranged from 0.01 to 3.15 grams per square meter per day at the ambient temperature of the measurements. The summer mean SOD rate was 3.0-times larger than the late fall mean rate, likely because of increased biological activity at warm water temperatures. Given the substantial amount of variability in SOD rates possible within sites, heterogeneity of substrate type is an important consideration when designing SOD studies and interpreting the results. Sediment oxygen demand in eastern Kansas streams was correlated with land use and streambed-sediment characteristics, though the strength of relations varied seasonally. The small number of study sites precluded a more detailed analysis. The effect of basin land use and streambed sediment characteristics on SOD is currently (2016) not well understood, and there may be many contributing factors including basin influences on water quality that affect biogeochemical cycles and the biological communities supported by the stream.

Kansas↗

USGS2018

Hydrologic and water-quality characteristics of Caño Boquerón, Cabo Rojo, and Puerto Mosquito, Isla de Vieques, Puerto Rico, July 2015–July 2016

Coastal lagoons are common features of the Puerto Rico shoreline that provide habitat for commercial and recreational species and serve important roles in the nutrient cycle of the ecosystems. The U.S. Geological Survey, in cooperation with the Puerto Rico Environmental Quality Board, conducted a limnological study at Caño Boquerón in Cabo Rojo and at Puerto Mosquito on Isla de Vieques, Puerto Rico, to assess the principal mechanisms affecting the hydrology and water-quality characteristics of these coastal lagoons and provide baseline information to the regulatory agencies responsible for the management and conservation of these coastal waters and the preservation of their aquatic life. Field measurements and water samples were collected and processed during July 2015–July 2016 for analysis of physical, chemical, biological, and bacteriological characteristics. In addition, bathymetric surveys were made and sediment cores were collected in each lagoon to determine water volume and sediment deposition rate. Physicochemical properties assessed at Caño Boquerón indicated values were generally in compliance with Puerto Rico Environmental Quality Board standards; turbidity was occasionally slightly greater than the established standards, and dissolved oxygen concentration at bottom depths was lower than standards limits. Water transparency was evaluated through the Secchi disk method, and the average depth of disappearance was 1.0 meter (m) for Caño Boquerón and 1.9 m for Puerto Mosquito. Assessment of biological characteristics at both sites included primary productivity calculations as well as carbon production equivalents and monthly water sampling for bacteriological and nutrient analyses. For Caño Boquerón, gross plankton primary productivity averaged 3.38 grams of oxygen per cubic meter per day (gO 2 /m 3 -d); this value was computed as the sum of net phytoplankton primary productivity (0.74 gO 2 /m 3 -d) and plankton respiration (2.64 gO 2 /m 3 -d). Net community primary productivity averaged 1.44 gO 2 /m 3 -d, and the community respiration rate averaged 8.10 gO 2 /m 3 -d, which indicates that the biological community, aside from phytoplankton, acts as a net consumer rather than a net producer of biomass. In Puerto Mosquito, gross plankton primary productivity averaged 2.07 gO 2 /m 3 -d, of which 0.39 gO 2 /m 3 -d could be ascribed to net phytoplankton primary productivity, and 1.68 gO 2 /m 3 -d could be ascribed to plankton respiration. Diel studies conducted at Puerto Mosquito reflected an average net community primary productivity of 2.43 gO 2 /m 3 -d, and the average respiration rate was 6.72 gO 2 /m 3 -d. In a bathymetric survey conducted in August 2015, the water volume for the Caño Boquerón lagoon was calculated as 967,000 cubic meters (m 3 ), and the water volume at Puerto Mosquito was calculated as 1,182,200 m 3 , with an average depth of 1.5 m for Caño Boquerón and 1.8 m for Puerto Mosquito. The daily seawater exchange for Caño Boquerón and Puerto Mosquito was 13 and 5 percent of their water volumes referenced to mean sea level, respectively. A total of 20 sediment samples were processed and analyzed for cesium-137 ( 137 Cs) and lead-210 ( 210 Pb) radioisotopes. Analyses indicated that the sediment deposition rate at Caño Boquerón ranged from 0.32 to 0.36 centimeter per year, based on age dating analysis of 137 Cs and 210 Pb data; in Puerto Mosquito, the sediment deposition rate ranged from 0.26 to 0.27 centimeter per year, based on 137 Cs and 210 Pb data. Bacteriological analyses at Caño Boquerón and Puerto Mosquito indicated that fecal coliform and enterococci concentrations were below Puerto Rico Environmental Quality Board standards during the study. The highest concentrations of fecal coliform (22 colonies per 100 milliliters) and enterococci (9 colonies per 100 milliliters) at Caño Boquerón occurred in July, which coincided with the busiest season of vacation rentals near the lagoon. Bacteria concentrations were generally lower in Puerto Mosquito than in Caño Boquerón; maximum concentrations of fecal coliform and enterococci bacteria were measured in November 2015. The potential sources of contamination for Puerto Mosquito are limited, because it is within a conservation area.

Caño Boquerón, Cabo Rojo, Puerto Mosquito, Isla de↗

USGS2021

Use of dissolved oxygen monitoring to evaluate phosphorus loading in Connecticut streams, 2015–18

The Connecticut Department of Energy and Environmental Protection (CT DEEP) has developed an interim phosphorus reduction strategy to establish water-quality-based phosphorus limits in nontidal freshwaters for industrial and municipal water pollution control facilities. A recommendation in the strategy included the addition of diurnal dissolved oxygen (DO) sampling to the sampling of diatom communities collected by CT DEEP. The chemistry data coupled with biological data will help to examine the effects of phosphorus loading in streams. The U.S. Geological Survey (USGS), in cooperation with the CT DEEP and New England Interstate Water Pollution Control Commission, implemented a summer DO monitoring program from 2015 to 2018 to examine the effects of phosphorus loading in streams. Continuous DO data were collected at 18 sites in streams with varying concentrations of phosphorus throughout the State of Connecticut. Discrete water-quality nutrient data were collected by the USGS at 11 of the 18 sites. All continuous and discrete data collected from June to September for the 4 years were examined for all sites. This report documents a pattern of diurnal DO for monitoring sites across 4 years and presents estimated daily gross primary productivity (GPP), ecosystem respiration (ER), and a standardized rate coefficient for gas exchange for selected streams. Relations of phosphorus concentrations to the diurnal DO response and stream metabolism are described. Interannual variability in average annual total phosphorus (TP) concentrations and maximum daily DO concentrations were evaluated among sites in years of the study. Streams identified as impaired by CT DEEP such as Naugatuck River at Beacon Falls (USGS station 01208500), Still River at Route 7 at Brookfield Center (USGS station 01201487), and Quinnipiac River at Wallingford (USGS station 01196500) had higher TP concentrations (greater than 0.10 milligram per liter [mg/L]) throughout the study. Reference streams considered unimpaired had lower concentrations of TP (less than 0.10 mg/L). The range in daily DO concentrations remained less than 4 mg/L for most of the sites during the study except for Naugatuck River at Beacon Falls and Still River at Route 7 at Brookfield Center. Daily GPP and ER were summarized for 11 sites using the maximum likelihood estimation model of the streamMetabolizer package in the R statistical program. The models indicated that most sites had an estimated negative net primary productivity, based on the daily estimates of GPP and ER, which indicates the systems are heterotrophic and dominated by respiration. The high variation of GPP and ER reported for several sites can be affected by many physical, chemical, and biological factors, including the abundance and community composition of phytoplankton, periphyton, and macrophyte algae present. The variability in mean GPP was similar to the variability in maximum DO concentrations when plotted against annual average TP concentrations for the maximum likelihood estimation model in streamMetabolizer. The concept that phosphorus loading can affect the stream metabolism requires more detailed knowledge of stream geomorphic variables (canopy cover, stream velocity, water depth) and algal communities to help improve the scientific basis for managing phosphorus loading.

Connecticut↗

USGS2023

Hydrologic framework and characterization of the Little Colorado River alluvial aquifer near Leupp, Arizona

The Little Colorado River alluvial aquifer near Leupp, Arizona, was investigated as a possible source of irrigation water for the Leupp and Birdsprings Chapters of the Navajo Nation. The physical, chemical, and hydraulic characteristics of the alluvial aquifer were studied using geophysical surveys, installation of observation wells, water-level measurements, chemical analyses, groundwater pumping simulations, and review of previous investigations. Geophysical surveys and well borings revealed that the aquifer ranges in thickness from near 0 feet around its periphery to about 100 feet in its thickest parts. Water levels were monitored in nine alluvial wells within the study area and compared with earlier measurements collected in 1998 and 1999. Comparison of those earlier water levels with water levels collected as part of this study showed a decline of between about 5 and 12 feet has occurred in the last 23 years. The water chemistry of the aquifer was analyzed for salinity hazard, sodium-adsorption hazard, and specific-ion toxicity. The sodium-adsorption hazard and specific-ion toxicity of alluvial aquifer water were found to be low. However, the salinity hazard was high enough in most areas that it could negatively affect salt-sensitive crops. Well-field pumping scenarios conducted for this study demonstrated that using groundwater from the alluvial aquifer for irrigated agriculture is theoretically possible but may be economically challenging owing to the hydraulic properties of the aquifer.

Arizona↗

USGS1947

Present investigations of radioactive raw materials by the Geological Survey and a recommended program for future work

The Geological Survey's program of investigation of radioactive raw materials is presented herewith under present investigations, plans for future investigations, plan of operation, and cost of operation. This report was prepared at the request of the Atomic Energy Commission. Present investigations are summarized to show the scope of the present Trace Elements program, grouping individual projects into related types of investigations. Plans for future investigations on an expanded scale are outlined. These should provide sufficient data and knowledge of the occurrence and availability of uranium, thorium, and related elements, to permit a more complete evaluation of domestic resources. Reconnaissance projects are designed to discover possible new sources of uranium and thorium and to select areas and materials warranting further investigation. Typical projects leading to the estimation of reserves are the investigation of the carnotite ores of the Colorado Plateau by geologic mapping, exploratory drilling, and related research, and investigation of asphaltic sandstone in Emery County, Utah. Extensive research will be undertaken to establish the principles governing the geological and geochemical relations of uranium, thorium, and associated elements as an essential guide in appraising domestic resources. Particular emphasis will be placed on phosphatic rocks and black shales which offer ultimate resources of uranium far greater than carnotite ores. All the foregoing investigations will be accompanied by chemical, gephysical, and mineralogical research and analytical work. Under plan of operation is discussed the organization of the Trace Elements Unit, space requirements for laboratory and office, the scheduling of investigations, and other related problems. The proposed scheduling of work calls for approximately 109, 173, and 203 man years in fiscal years 1948, 1949, and 1950 respectively. Definite plans have been formulated only for the next three fiscal years, by which time it is assumed the program will reach stable proportions or can be altered as experience dictates. Under cost of operation is set forth the funds available in fiscal year 1947, the status of funds transferred from Atomic Services (14-217/80920), and funds necessary in succeeding fiscal years. The estimate for fiscal year 1948 inclues a non-recurring item of $1,025,000 for establishing adequate laboratories for chemical, physical, spectrographic and mineralogic research and analytical work. The total funds required in fiscal years 1948, 1949, and 1950 to support the proposed program will be $2,440,000, $2,161,000 and $2,198,000 respectively. The Geological survey anticipates contributing from its appropriation in fiscal years 1948, 1949 and 1950 approximately $243,000, $350,000, and $400,000 respectively; the balance of the necessary funds to be contributed by the Atomic Energy Commission in fiscal years 1948, 1949, and 1950 will be approximately $2,196,900, $1,811,000, and $1,798,000 respectively.

Trace Elements Investigations↗

USGS1957

Reconnaissance of beryl-bearing pegmatites in the Ruby Mountains, other areas in Nevada, and northwestern Mohave County, Arizona

Pegmatite occurs widely in Nevada and northwestern Arizona, but little mining has been done for such pegmatite minerals as mica, feldspar, beryl, and lepidolite. Reconnaissance for beryl-bearing pegmatite in Nevada and in part of Mohave County, Ariz., and detailed studies in the Dawley Canyon area, Elko County, Nev., have shown that beryl occurs in at least 11 districts in the region. Muscovite has been prospected or mined in the Ruby Mountains and the Virgin Mountains, Nevada, and in Mohave County, Ariz. Feldspar has been mined in the southern part of the region near Kingman, Ariz., and in Clark County, Nev. The pegmatites in the region range in age from Precambrian to late Mesozoic or Tertiary. Among the pegmatite minerals found or reported in the districts studied are beryl, chrysoberyl, scheelite, wolframite, garnet, tourmaline, fluorite, apatite, sphene, allanite, samarskite, euxenite, gadolinite, monazite, autunite, columbite-tantalite, lepidolite, molybdenite, and pyrite and other sulfide minerals. The principal beryl-bearing pegmatites examined are in the Oreana and Lakeview (Humboldt Canyon) areas, Pershing County; the Dawley Canyon area in the Ruby Mountains, Elko County, Nev.; and on the Hummingbird claims in the Virgin Mountains, Mohave County, Ariz. Beryl has also been reported in the Marietta district, Mineral County; the Sylvania district, Esmeralda County; near Crescent Peak and near Searchlight, Clark County, Nev.; and in the Painted Desert area near Hoover Dam, Mohave County, Ariz. Pegmatites are abundant in the Ruby Mountains, chiefly in the area north of the granite stock at Harrison Pass. In the Dawley Canyon area of 2.6 square miles at least 350 pegmatite dikes more than a foot thick were mapped and beryl was found in small quantities in at least 100 of these dikes. Four of these dikes exceed 20 feet in thickness, and one is 55 feet thick. A few pegmatites were also examined in the Corral Creek, Gilbert Canyon, and Hankins Canyon areas in the Ruby Mountains. The pegmatite dikes in the Dawley Canyon area intrude granite and metamorphic rocks which consist chiefly of quartzite and schist of probable Early Cambrian age. The granite is of two types: a biotite-muscovite granite that forms the main mass of the stock and muscovite granite that occurs in the metamorphic rocks near the borders of the stock. The pegmatites were emplaced chiefly along fractures in the granite and along schistosity or bedding planes in the metamorphic rocks. Many of the Dawley Canyon pegmatite dikes are zoned, having several rock units of contrasting mineralogy or grain size successively from the walls inward. Aplitic units occur either as zones or in irregular positions in the pegmatite dikes and are a distinctive feature of the Dawley Canyon pegmatites. Some of the aplitic and fine-grained pegmatite units are characterized by thin layers of garnet crystals, forming many parallel bands on outcrop surfaces. The occurrence of aplitic and pegmatitic textural varieties in the same dike presumably indicates abrupt changes in physical-chemical conditions during crystallization, such as changes in viscosity and in content of volatile constituents. Concentrations of 0.1 percent or more beryl, locally more than 1 percent, occur in certain zones or parts of zones in the Dawley Canyon pegmatites. Spectrographic analyses of 23 samples indicate that the BeO content ranges from 0.0017 to 0.003 percent in the muscovite granite, from 0.0013 to 0.039 percent in aplitic zones in pegmatite, from 0.0005 to 0.10 percent in coarse-grained pegmatite, and from less than 0.0001 to 0.0004 percent in massive quartz veins. The scheelite-beryl deposits at Oreana and in Humboldt Canyon, Pershing County., are rich in beryllium. Twelve samples from the Humboldt Canyon (Lakeview) deposit range from 0.018 to 0.11 percent BeO, but underground crosscuts have failed to intersect similar rock at depth. Beryl locally constitutes as much as 10 percent of the pegmati tic ore at Oreana. The beryl was not recovered during tungsten mining at Oreana and is now in the tailings of the mill at Toulon, Nevada, in lower percentages than the Oreana ore because of dilution by tailings from other ores milled at Toulon. Beryl has been found in numerous pegmatite dikes in the Virgin Mountains. Both beryl and chrysoberyl occur in dikes in the Hummingbird claims, north of Virgin Peak, in Mohave County, Ariz. Spectra graphic analyses of five representative samples of the principal dike on the Hummingbird claims range from 0.055 to 0.11 percent BeO.

Arizona, Nevada↗

USGS2024

Guidelines for the use of automatic samplers in collecting surface-water quality and sediment data

The importance of fluvial systems in the transport of sediment, dissolved and suspended contaminants, nutrients, and bacteria through the environment is well established. The U.S. Environmental Protection Agency (EPA) identifies sediment as the single most widespread water contaminant affecting the beneficial uses of the Nation’s rivers and streams. The evaluation of water-quality as it relates to agriculture, urbanization, highway and residential construction, mining, industrial and human wastes, and other activities requires an extensive data and sample-collection effort. This is especially the case when studying urbanized river basins, where during hydrologic events, concentration of suspended sediment and contaminants can vary rapidly and over large ranges. Where synoptic studies of watersheds are called for, sampling may be needed at many sites throughout the basin; a complicated and difficult task in some settings. Automatic pumping samplers (autosamplers) are one method for conducting intensive time-varying sampling throughout watersheds. This report presents guidelines for the use of autosamplers for collecting surface-water samples by the U.S. Geological Survey. An autosampler is an automatic, pump-based sampler that collects a prescribed volume of water from streams, lakes, reservoirs, storm drains, or other bodies of water after receiving a command from an internal or external control unit. It deposits this sample into a specified container for later analysis of physical, chemical, or biological constituents. This report provides a general background on types of autosamplers and how they work; guidance for designing, selecting, installing, servicing, and calibrating autosamplers; guidance on standardized operating procedures, and guidance on quality-assurance and quality-control efforts when using an autosampler.

Techniques and Methods↗

USGS2005

UCODE_2005 and six other computer codes for universal sensitivity analysis, calibration, and uncertainty evaluation constructed using the JUPITER API

This report documents the computer codes UCODE_2005 and six post-processors. Together the codes can be used with existing process models to perform sensitivity analysis, data needs assessment, calibration, prediction, and uncertainty analysis. Any process model or set of models can be used; the only requirements are that models have numerical (ASCII or text only) input and output files, that the numbers in these files have sufficient significant digits, that all required models can be run from a single batch file or script, and that simulated values are continuous functions of the parameter values. Process models can include pre-processors and post-processors as well as one or more models related to the processes of interest (physical, chemical, and so on), making UCODE_2005 extremely powerful. An estimated parameter can be a quantity that appears in the input files of the process model(s), or a quantity used in an equation that produces a value that appears in the input files. In the latter situation, the equation is user-defined. UCODE_2005 can compare observations and simulated equivalents. The simulated equivalents can be any simulated value written in the process-model output files or can be calculated from simulated values with user-defined equations. The quantities can be model results, or dependent variables. For example, for ground-water models they can be heads, flows, concentrations, and so on. Prior, or direct, information on estimated parameters also can be considered. Statistics are calculated to quantify the comparison of observations and simulated equivalents, including a weighted least-squares objective function. In addition, UCODE_2005 can be used fruitfully in model calibration through its sensitivity analysis capabilities and its ability to estimate parameter values that result in the best possible fit to the observations. Parameters are estimated using nonlinear regression: a weighted least-squares objective function is minimized with respect to the parameter values using a modified Gauss-Newton method or a double-dogleg technique. Sensitivities needed for the method can be read from files produced by process models that can calculate sensitivities, such as MODFLOW-2000, or can be calculated by UCODE_2005 using a more general, but less accurate, forward- or central-difference perturbation technique. Problems resulting from inaccurate sensitivities and solutions related to the perturbation techniques are discussed in the report. Statistics are calculated and printed for use in (1) diagnosing inadequate data and identifying parameters that probably cannot be estimated; (2) evaluating estimated parameter values; and (3) evaluating how well the model represents the simulated processes. Results from UCODE_2005 and codes RESIDUAL_ANALYSIS and RESIDUAL_ANALYSIS_ADV can be used to evaluate how accurately the model represents the processes it simulates. Results from LINEAR_UNCERTAINTY can be used to quantify the uncertainty of model simulated values if the model is sufficiently linear. Results from MODEL_LINEARITY and MODEL_LINEARITY_ADV can be used to evaluate model linearity and, thereby, the accuracy of the LINEAR_UNCERTAINTY results. UCODE_2005 can also be used to calculate nonlinear confidence and predictions intervals, which quantify the uncertainty of model simulated values when the model is not linear. CORFAC_PLUS can be used to produce factors that allow intervals to account for model intrinsic nonlinearity and small-scale variations in system characteristics that are not explicitly accounted for in the model or the observation weighting. The six post-processing programs are independent of UCODE_2005 and can use the results of other programs that produce the required data-exchange files. UCODE_2005 and the other six codes are intended for use on any computer operating system. The programs consist of algorithms programmed in Fortran 90/95, which efficiently performs numerical calculations. The model runs required to obtain perturbation sensitivities can be performed using multiple processors. The programs are constructed in a modular fashion using JUPITER API conventions and modules. For example, the data-exchange files and input blocks are JUPITER API conventions and many of those used by UCODE_2005 are read or written by JUPITER API modules. UCODE-2005 includes capabilities likely to be required by many applications (programs) constructed using the JUPITER API, and can be used as a starting point for such programs.

Techniques and Methods↗

USGS2015

National Field Manual for the Collection of Water-Quality Data. U.S. Geological Survey Techniques of Water-Resources Investigations, Book 9

The mission of the Water Resources Discipline of the U.S. Geological Survey (USGS) is to provide the information and understanding needed for wise management of the Nation's water resources. Inherent in this mission is the responsibility to collect data that accurately describe the physical, chemical, and biological attributes of water systems. These data are used for environmental and resource assessments by the USGS, other government agenices and scientific organizations, and the general public. Reliable and quality-assured data are essential to the credibility and impartiality of the water-resources appraisals carried out by the USGS. The development and use of a National Field Manual is necessary to achieve consistency in the scientific methods and procedures used, to document those methods and procedures, and to maintain technical expertise. USGS field personnel use this manual to ensure that the data collected are of the quality required to fulfill our mission.

Techniques of Water-Resources Investigations↗

USGS1974

Water resources data for California, 1973; Part 2: Water quality records

Water-resources data for the 1973 water year for California include records of data for the chemical, physical, and biological characteristics of surface and ground water. These data were collected from designated sampling sites at predetermined intervals such as once daily, weekly, monthly, or less frequently, and at some sites data were recorded on punched paper tape at 15-, 30-, or 60- minute intervals. The distribution, type, and number of stations in each river or drainage basin are shown in figure 1. A few pertinent stations in bordering States are also included. These records were compiled by the Water Resources Division of the U.S. Geological Survey under the direction of Lee R. Peterson, district chief. These data represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in California.

California↗

USGS1976

Water resources data for California, water year 1975; Volume 3: Southern Central Valley Basins and The Great Basin from Walker River to Truckee River

Water-resources data for the 1975 water year for California consist of records of streamflow and contents of reservoirs at gaging stations, partial-record stations, and miscellaneous sites; records of water quality including the physical, chemical, and biological characteristics of surface and ground water; and records of water levels in selected observation wells. Records for a few pertinent streamflow and water-quality stations in bordering States are also included. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of Lee R. Peterson, district chief; Winchell Smith, assistant district chief for hydrologic data; and Leonard N. Jorgensen, chief of the basic data section. These data represent that part of the National Water Data System collected by the Geological Survey and cooperating local, State, and Federal agencies in California.

California↗

USGS1977

Water resources data for California, water year 1975; Volume 4: Northern Central Valley basins and the Great Basin from Honey Lake basin to Oregon state line

California↗