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Field spikes were prepared at 207 stream and river sites as part of the U.S. Geological Survey (USGS) National Water Quality Assessment (NAWQA) project between December, 2012, and September, 2015. At the field site, a depth-and width-integrated environmental sample was collected, and one subsample of the environmental sample was spiked with a known amount of a spike mixture. Both the spiked subsample ("spike sample") and another subsample ("environmental sample") of the original water sample were analyzed for pesticides at the USGS National Water Quality Laboratory (NWQL) by direct injection liquid chromatography with tandem mass spectrometry (LC-MS/MS), and were used to calculate the spike recovery of each analyte....
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High radium (Ra) concentrations in potable portions of the Cambrian-Ordovician (C-O) aquifer system were investigated using water-quality data and environmental tracers ( 3H, 3Hetrit, SF6 , 14C and 4Herad) of groundwater age from 80 public-supply wells (PSWs). Groundwater ages were estimated by calibration of tracers to lumped parameter models and ranged from modern (1 Myr) in the most downgradient, confined portions of the potable system. More than 80 and 40 percent of mean groundwater ages were older than 1000 and 50,000 yr, respectively. Anoxic, Fe-reducing conditions and increased mineralization develop with time in the aquifer system and mobilize Ra into solution resulting in the frequent occurrence of combined...
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The glacial aquifer system of the United States encompasses all or parts of 25 states and is the most widely used supply of drinking water in the Nation (Maupin and Barber, 2005; Maupin and Arnold, 2010). A series of seven raster data sets were derived from a database of water-well drillers' records that was compiled in partial fulfillment of the goals of the U.S. Geological Survey’s Groundwater Availability and Use assessment program (U.S. Geological Survey, 2002). They contain hydrogeologic information for areas of the U.S. that are north of the southern limit of Pleistocene glaciation, including the total thickness of glacial deposits, thickness of coarse-grained sediment within the glacial deposits, specific-capacity...
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This map layer consists of federally owned or administered lands of the United States, Puerto Rico, and the U.S. Virgin Islands. For the most part, only areas of 320 acres or more are included; some smaller areas deemed to be important or significant are also included. There may be private inholdings within the boundaries of Federal lands in this map layer. Some established Federal lands which are larger than 320 acres are not included in this map layer, because their boundaries were not available from the owning or administering agency.
Tags: Air Force, Alabama, Alaska, Arizona, Arkansas, All tags...
In this paper, we present an economic analysis of CO2-enhanced oil recovery (EOR). This technique entails injection of CO2 into mature oil fields in a manner that reduces the oil's viscosity, thereby enhancing the rate of extraction. As part of this process, significant quantities of CO2 remain sequestered in the reservoir. If CO2 emissions are regulated, oil producers using EOR should therefore be able to earn revenues from sequestration as well as from oil production. We develop a theoretical framework that analyzes the dynamic co-optimization of oil extraction and CO2 sequestration, through the producer's choice of the fraction of CO2 in the injection stream at each moment. We find that the optimal fraction of...
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This dataset provides timeseries data on water quality and quantity, as collected or computed from outside sources. The format is many tables with one row per time series observation (1 tab-delimited file per site-variable combination, 1 zip file per site). This compilation of data is intended for use in estimating or interpreting metabolism. Sites were included if they met the initial criteria of having at least 100 dissolved oxygen observations and one of the accepted NWIS site types ('ST','ST-CA','ST-DCH','ST-TS', or 'SP'). This dataset is part of a larger data release of metabolism model inputs and outputs for 356 streams and rivers across the United States (https://doi.org/10.5066/F70864KX). The complete release...
Tags: 007, 012, AK, AL, AR, All tags...
In this paper, we present an economic analysis of CO2-enhanced oil recovery (EOR). This technique entails injection of CO2 into mature oil fields in a manner that reduces the oil's viscosity, thereby enhancing the rate of extraction. As part of this process, significant quantities of CO2 remain sequestered in the reservoir. If CO2 emissions are regulated, oil producers using EOR should therefore be able to earn revenues from sequestration as well as from oil production. We develop a theoretical framework that analyzes the dynamic co-optimization of oil extraction and CO2 sequestration, through the producer's choice of the fraction of CO2 in the injection stream at each moment. We find that the optimal fraction of...
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The glacial aquifer system of the United States encompasses all or parts of 25 states and is the most widely used supply of drinking water in the Nation (Maupin and Barber, 2005; Maupin and Arnold, 2010). A series of seven raster data sets were derived from a database of water-well drillers' records that was compiled in partial fulfillment of the goals of the U.S. Geological Survey’s Groundwater Availability and Use assessment program (U.S. Geological Survey, 2002). They contain hydrogeologic information for areas of the U.S. that are north of the southern limit of Pleistocene glaciation, including the total thickness of glacial deposits, thickness of coarse-grained sediment within the glacial deposits, specific-capacity...
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This map layer shows Indian lands of the United States. For the most part, only areas of 320 acres or more are included; some smaller areas deemed to be important or significant are also included. Federally-administered lands within a reservation are included for continuity; these may or may not be considered part of the reservation and are simply described with their feature type and the administrating Federal agency. Some established Indian lands which are larger than 320 acres are not included in this map layer because their boundaries were not available from the owning or administering agency.
Tags: Alabama, Alaska, Arizona, Arkansas, BIA, All tags...
Geographic distribution data were collected based on county level occurrences (or converted from point occurrences to county level occurrences) within the five focal states (Minnesota, North Dakota, South Dakota, Nebraska & Iowa) and each U.S. state or Canadian province bordering those focal states (Wisconsin, Illinois, Missouri, Kansas, Wyoming, & Montana in the USA and Saskatchewan, Ontario & Manitoba in Canada).
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Layered GeoPDF 7.5 Minute Quadrangle Map. Layers of geospatial data include orthoimagery, roads, grids, geographic names, elevation contours, hydrography, and other selected map features.