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USGS2016

Social-value maps for Arapaho, Roosevelt, Medicine Bow, Routt, and White River National Forests, Colorado and Wyoming

Executive Summary The continued pressures of population growth on the life-sustaining, economic, and cultural ecosystem services provided by our national forests, particularly those located near rapidly growing urban areas, present ongoing challenges to forest managers. Achieving an effective assessment of these ecosystem services includes a proper accounting of the ecological, economic, and social values attributable to them. However, assessments of ecosystem goods and services notably lack information describing the spatial distribution and relative intensity of social values—the perceived, nonmarket values derived particularly from cultural ecosystem services. A geographic information system (GIS) tool developed to fill this need, Social Values for Ecosystem Services (SolVES; http://solves.cr.usgs.gov ), now provides the capability to generate social-value maps at a range of spatial scales. This report presents some of the methods behind SolVES, procedures needed to apply the tool, the first formal map products resulting from its application at a regional scale, and a discussion of the management implications associated with this type of information. In this study, we use SolVES to identify the location and relative intensity of social values as derived from survey responses gathered from residents living in counties adjacent to Arapaho, Roosevelt, Medicine Bow, Routt, and White River National Forests. The results, presented as a series of social-value maps, represent the first publicly available spatial data on social-value intensity for the southern Rocky Mountain region. Our analysis identified high-value areas for social values including aesthetic, biodiversity, and life sustaining within wilderness areas. Other values, like recreation, show high-value areas both within wilderness and throughout the general forest areas, which can be attributed to people using the forests for a diverse set of recreational activities. The economic social-value type was lower within wilderness areas, which was an expected outcome because of the restrictions inside wilderness areas that preclude resource extraction, development, and motorized or mechanized recreation. Providing spatially explicit social-value information collected from residents in counties adjacent to these national forests can assist in facilitating the U.S. Department of Agriculture Forest Service’s Multiple-Use Sustained-Yield Act of 1960 (16 U.S.C. 528) note and the 2012 Forest Service Planning Rule (36 CFR Part 219), which encourage public participation in planning and management. By making these maps available to the public, we hope to encourage exploration of potential uses of these data for resource management and planning.

Colorado, Wyoming↗
USGS2024

Characterization of groundwater resources near the southeastern part of Puget Sound, Washington

More than 1 million people live within the active model area (AMA) in the southeastern part of the lowlands surrounding Puget Sound, or Puget Lowland, Washington, and groundwater is the source for approximately one-half of their public, domestic, and irrigation water demands. The 887-square-mile AMA, located in King and Pierce Counties, represents the area of analysis for the conceptual hydrogeologic framework and numerical groundwater-flow models within the study area and includes the Puyallup River and Chambers-Clover Creek watersheds. To assess the potential hydrologic and anthropogenic impacts to groundwater and the connected surface-water resources, conceptual and numerical groundwater-flow models of groundwater flow were developed by the U.S. Geological Survey Washington Water Science Center in close cooperation with 18 water-resource agencies and stakeholders. This multichapter volume documents the development of the conceptual and numerical groundwater-flow models of groundwater flow. Chapters A, B, and C provide an overall introduction to the multichapter volume (Chapter A), the conceptual hydrogeologic framework (Chapter B), and the groundwater budget (Chapter C). Chapters D and E describe numerical groundwater-flow model construction and calibration (Chapter D) and the numerical groundwater-flow model results (Chapter E). Collectively, these reports present a characterization and simulation tool for groundwater resources near the southeastern part of Puget Sound, Washington.

Scientific Investigations Report↗
USGS2011

Wolf population dynamics in the U.S. Northern Rocky Mountains are affected by recruitment and human-caused mortality

Reliable analyses can help wildlife managers make good decisions, which are particularly critical for controversial decisions such as wolf (Canis lupus) harvest. Creel and Rotella (2010) recently predicted substantial population declines in Montana wolf populations due to harvest, in contrast to predictions made by Montana Fish, Wildlife and Parks (MFWP). We replicated their analyses considering only those years in which field monitoring was consistent, and we considered the effect of annual variation in recruitment on wolf population growth. Rather than assuming constant rates, we used model selection methods to evaluate and incorporate models of factors driving recruitment and human-caused mortality rates in wolf populations in the Northern Rocky Mountains. Using data from 27 area-years of intensive wolf monitoring, we show that variation in both recruitment and human-caused mortality affect annual wolf population growth rates and that human-caused mortality rates have increased with the sizes of wolf populations. We document that recruitment rates have decreased over time, and we speculate that rates have decreased with increasing population sizes and/or that the ability of current field resources to document recruitment rates has recently become less successful as the number of wolves in the region has increased. Estimates of positive wolf population growth in Montana from our top models are consistent with field observations and estimates previously made by MFWP for 2008–2010, whereas the predictions for declining wolf populations of Creel and Rotella (2010) are not. Familiarity with limitations of raw data, obtained first-hand or through consultation with scientists who collected the data, helps generate more reliable inferences and conclusions in analyses of publicly available datasets. Additionally, development of efficient monitoring methods for wolves is a pressing need, so that analyses such as ours will be possible in future years when fewer resources will be available for monitoring.

Idaho, Montana, Wyoming↗
USGS2026

Evidence of ringtail expansion into Idaho, USA

Ringtails ( Bassariscus astutus ) are widely distributed in the western United States and across much of Mexico, yet due to their relatively low densities and cryptic nature, little is known about their basic ecology even where they are common. Recent public sightings suggest ringtails may have expanded their distribution north into southern Idaho, USA. Currently, ringtails remain unclassified in Idaho thus limiting resources and time available for population monitoring. We attempted to detect these small carnivores in southern Idaho during winter 2023. We deployed 49 camera traps with a combination of lures (i.e., trapping lure, fruit, and orange drink mix) in canyon habitats in southern Idaho near recent ringtail sightings. We detected ringtails nine times on six different camera traps. Although incidental ringtail observations increased in southern Idaho since the early 2000s, our detections were the first to result from a targeted survey effort. Given more than 20 years of incidental sightings and multiple detections during our survey, it appears that ringtails have expanded their range northward into southern Idaho and could be considered a resident species in the state. Further efforts to document reproduction, annual persistence, and an assessment of threats could be next steps if the state wildlife management agency deems it a priority and an appropriate use of resources.

Idaho↗
USGS2017

Implementing the 2012 North American Waterfowl Management Plan revision: Populations, habitat, and people

The North American Waterfowl Management Plan (NAWMP) has established a model for wildlife conservation planning over the last 3 decades. Management at a continental scale, leveraged funding, regional partnerships, and a strong science basis have been notable features. Periodic updates to the NAWMP occurred since implementation in 1986; however, a fundamental revision was accomplished in 2012 after extensive stakeholder engagement. An explicit fundamental goal for waterfowl conservation supporters was added in 2012, complementing existing goals for sustainable populations and sufficient habitat found in previous updates. We present a synopsis of progress toward implementation of the 2012 NAWMP and challenge the waterfowl management community to continue with meaningful steps toward achieving NAWMP goals. Adding goals and objectives for supporters increases potential relevance of NAWMP; however, it also presents a level of complexity that was not entirely anticipated. Additionally, the 2012 NAWMP recognized that traditional support from waterfowl hunters alone will not be sufficient to support waterfowl conservation in the future. Simultaneous consideration of multiple objectives, although implicit before, now is a specific focus for habitat and harvest management affecting hunters and other users of the waterfowl resource. The waterfowl management community is faced with revisiting objectives and management actions related to harvest regulations, landscape priorities, habitat conservation, and public engagement to garner broader support. These persistent management challenges are tangible and relevant candidates for greater integration. Ultimately, the structures and processes supporting waterfowl management also will need to be reconsidered.

Journal of Wildlife Management↗
USGS2011

U.S. Department of Energy's site screening, site selection, and initial characterization for storage of CO 2 in deep geological formations

The U.S. Department of Energy (DOE) is the lead Federal agency for the development and deployment of carbon sequestration technologies. As part of its mission to facilitate technology transfer and develop guidelines from lessons learned, DOE is developing a series of best practice manuals (BPMs) for carbon capture and storage (CCS). The "Site Screening, Site Selection, and Initial Characterization for Storage of CO 2 in Deep Geological Formations" BPM is a compilation of best practices and includes flowchart diagrams illustrating the general decision making process for Site Screening, Site Selection, and Initial Characterization. The BPM integrates the knowledge gained from various programmatic efforts, with particular emphasis on the Characterization Phase through pilot-scale CO 2 injection testing of the Validation Phase of the Regional Carbon Sequestration Partnership (RCSP) Initiative. Key geologic and surface elements that suitable candidate storage sites should possess are identified, along with example Site Screening, Site Selection, and Initial Characterization protocols for large-scale geologic storage projects located across diverse geologic and regional settings. This manual has been written as a working document, establishing a framework and methodology for proper site selection for CO 2 geologic storage. This will be useful for future CO 2 emitters, transporters, and storage providers. It will also be of use in informing local, regional, state, and national governmental agencies of best practices in proper sequestration site selection. Furthermore, it will educate the inquisitive general public on options and processes for geologic CO 2 storage. In addition to providing best practices, the manual presents a geologic storage resource and capacity classification system. The system provides a "standard" to communicate storage and capacity estimates, uncertainty and project development risk, data guidelines and analyses for adequate site characterization, and guidelines for reporting estimates within the classification based on each project's status.

Conference Paper↗
USGS2011

Coastal sedimentary research examines critical issues of national and global priority

An international conference was held recently in Honolulu, Hawaii, to examine and plan for coastal sedimentary research in the United States and globally. Participants agreed that sedimentary coastal environments constitute a critical national and global resource that suffers widespread degradation due to human impacts. Moreover, human population growth and inappropriate development in the coastal zone are escalating public asset losses due to coastal hazards and placing large numbers of communities at growing risk (Figure 1).

Hawai'i↗
USGS2014

Report of the Committee on Underground Waters, 1934–35

The annual report this year consists almost wholly of a brief summary of investigations in progress in different parts of the country. It is by no means complete, and the Chairman of the Committee will be glad to receive information in regard to investigations that have not been mentioned. The outstanding feature of the past year has been the focusing of public attention on problems of underground water, as a result of the drought-conditions, the activities of the National and State resource and planning surveys, and the creation of emergency-relief projects.

Eos, Transactions, American Geophysical Union↗
USGS2024

K-12 trade books’ representation of earthquake safety and protective actions: A content analysis

Meaningful learning resources for earthquake safety and survival have become an increasingly important topic among geoscientists, especially educators and researchers. Various members of the public, especially K-12 (ages 5–18) learners, continue to depend on scientific trade books available at their local public and school libraries for information about earthquake concepts. To our knowledge, no research has empirically examined how trade books represent earthquake safety and survival actions. In this research, we combine an iterative qualitative inductive and deductive analysis to explore the representation of earthquake safety and protective actions in 50 trade books. We categorize these actions into time-based practices related to preparedness before an earthquake, protective actions during an earthquake, and recovery after an earthquake. These trade books emphasize preparedness by means of building earthquake-resistant structures and urban planning, and efforts toward community resilience and keeping home supplies. The recommended personal protective action during an earthquake in the United States (“Drop, Cover, and Hold On”) is emphasized in the majority of the trade books, as well as other protective actions related to emotional actions and current technological automated actions such as earthquake early warning systems. Finally, the books highlight actions such as damage evaluation and support as ways to recover after an earthquake. Our findings highlight the issues between accepted earthquake safety and survival actions and the limited and/or inaccurate knowledge represented in some trade books. We provide interpretations of how presentation of limited or inaccurate information may increase confusion about appropriate protective actions. The inclusion of accepted and recommended protective actions in future trade books and the use of earthquake drills in public libraries as a supplement for trade book users may improve understanding and implementation of appropriate actions. We further demonstrate the potential of trade book contents in fostering earthquake education through library-community partnerships.

Journal of Geoscience Education↗
USGS2007

Bacteriological water quality in and around Lake Pontchartrain following Hurricanes Katrina and Rita

Following the Louisiana landfalls of Katrina on August 29 and Rita on September 24, 2005, the local population and the American public were concerned about the effects the hurricanes might have on water quality in Lake Pontchartrain. The lake is a major recreational resource for the region and an important fishery. Contamination carried by the storm surge—along with runoff and water pumped from flooded areas of New Orleans—was considered a serious threat to the water body. The USGS, in collaboration with the LDEQ, monitored the sanitary quality of water at 22 sites in and around Lake Pontchartrain, La., for 3 consecutive weeks from September 13 to 29, 2005 (fig. 1). A subsequent multipleagency survey of 30 sites within Lake Pontchartrain was undertaken by the U.S. Environmental Protection Agency (EPA), the USGS, and the National Oceanic and Atmospheric Administration during the week of October 11–14, 2005, to evaluate the effects of the hurricanes and overall levels of fecal contamination on the water quality of the lake (see Heitmuller and Perez, this volume). In addition, the EPA monitored fecal-indicator concentrations at a variety of sites in New Orleans, surrounding areas, and the Mississippi River between September 3 and October 22, 2005 (U.S. Environmental Protection Agency, 2006). This article describes fecal-indicator bacteria concentration results collected by USGS in the context of other existing data.

Louisiana↗
USGS2009

Groundwater quality data for the Tahoe-Martis study unit, 2007: Results from the California GAMA Program

Groundwater quality in the approximately 460-square-mile Tahoe–Martis study unit was investigated in June through September 2007 as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Project was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The study was designed to provide a spatially unbiased assessment of the quality of raw groundwater used for public water supplies within the Tahoe–Martis study unit (Tahoe–Martis) and to facilitate statistically consistent comparisons of groundwater quality throughout California. Samples were collected from 52 wells in El Dorado, Placer, and Nevada Counties. Forty-one of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study area (grid wells), and 11 were selected to aid in evaluation of specific water-quality issues (understanding wells). The groundwater samples were analyzed for a large number of synthetic organic constituents (volatile organic compounds [VOC], pesticides and pesticide degradates, and pharmaceutical compounds), constituents of special interest (perchlorate and N -nitrosodimethylamine [NDMA]), naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), radioactive constituents, and microbial indicators. Naturally occurring isotopes (tritium, carbon-14, strontium isotope ratio, and stable isotopes of hydrogen and oxygen of water), and dissolved noble gases also were measured to help identify the sources and ages of the sampled groundwater. In total, 240 constituents and water-quality indicators were investigated. Three types of quality-control samples (blanks, replicates, and samples for matrix spikes) each were collected at 12 percent of the wells, and the results obtained from these samples were used to evaluate the quality of the data for the groundwater samples. Field blanks rarely contained detectable concentrations of any constituent, suggesting that data for the groundwater samples were not compromised by possible contamination during sample collection, handling or analysis. Differences between replicate samples were within acceptable ranges. Matrix spike recoveries were within acceptable ranges for most compounds. This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, raw water typically is treated, disinfected, or blended with other waters to maintain water quality. Regulatory thresholds apply to water that is served to the consumer, not to raw groundwater. However, to provide some context for the results, concentrations of constituents measured in the raw groundwater were compared with regulatory and nonregulatory health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and the California Department of Public Health (CDPH), and with aesthetic and technical thresholds established by CDPH. Comparisons between data collected for this study and drinking-water thresholds are for illustrative purposes only and do not indicate of compliance or noncompliance with regulatory thresholds. The concentrations of most constituents detected in groundwater samples from the Tahoe–Martis wells were below drinking-water thresholds. Organic compounds (VOCs and pesticides) were detected in about 40 percent of the samples from grid wells, and most concentrations were less than 1/100th of regulatory and nonregulatory health-based thresholds, although the conentration of perchloroethene in one sample was above the USEPA maximum contaminant level (MCL-US). Concentrations of all trace elements and nutrients in samples from grid wells were below regulatory and nonregulatory health-based thresholds, with five exceptions. Concentrations of arsenic were above the MCL-US in 20 percent of the samples from grid wells. Gross alpha particle activity (MCL-US), boron (CDPH notification level, NL-CA), and molybdenum (USEPA lifetime health advisory, HAL-US) were each detected above thresholds in two of the samples from grid wells, and radon (proposed alternative MCL-US) was detected above the threshold in one sample from a grid well. Most of the samples from Tahoe–Martis grid wells had concentrations of major elements, total dissolved solids, and trace elements below the CDPH secondary maximum contaminant levels, nonenforceable thresholds set for aesthetic and technical concerns. Fifteen percent of the samples from grid wells contained iron, manganese, or total dissolved solids at concentrations above these levels.

California, Nevada↗
USGS2009

Groundwater quality data for the northern Sacramento Valley, 2007: Results from the California GAMA Program

Groundwater quality in the approximately 1,180-square-mile Northern Sacramento Valley study unit (REDSAC) was investigated in October 2007 through January 2008 as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Project was developed in response to the Groundwater Quality Monitoring Act of 2001, and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The study was designed to provide a spatially unbiased assessment of the quality of raw groundwater used for public water supplies within REDSAC and to facilitate statistically consistent comparisons of groundwater quality throughout California. Samples were collected from 66 wells in Shasta and Tehama Counties. Forty-three of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study area (grid wells), and 23 were selected to aid in evaluation of specific water-quality issues (understanding wells). The groundwater samples were analyzed for a large number of synthetic organic constituents (volatile organic compounds [VOC], pesticides and pesticide degradates, and pharmaceutical compounds), constituents of special interest (perchlorate and N-nitrosodimethylamine [NDMA]), naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), radioactive constituents, and microbial constituents. Naturally occurring isotopes (tritium, and carbon-14, and stable isotopes of nitrogen and oxygen in nitrate, stable isotopes of hydrogen and oxygen of water), and dissolved noble gases also were measured to help identify the sources and ages of the sampled ground water. In total, over 275 constituents and field water-quality indicators were investigated. Three types of quality-control samples (blanks, replicates, and sampmatrix spikes) were collected at approximately 8 to 11 percent of the wells, and the results for these samples were used to evaluate the quality of the data obtained from the groundwater samples. Field blanks rarely contained detectable concentrations of any constituent, suggesting that contamination was not a noticeable source of bias in the data for the groundwater samples. Differences between replicate samples were within acceptable ranges for nearly all compounds, indicating acceptably low variability. Matrix-spike recoveries were within acceptable ranges for most compounds. This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, raw groundwater typically is treated, disinfected, or blended with other waters to maintain water quality. Regulatory thresholds apply to water that is served to the consumer, not to raw ground water. However, to provide some context for the results, concentrations of constituents measured in the raw groundwater were compared with regulatory and nonregulatory health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and California Department of Public Health (CDPH) and with aesthetic and technical thresholds established by CDPH. Comparisons between data collected for this study and drinking-water thresholds are for illustrative purposes only and do not indicate compliance or noncompliance with those thresholds. The concentrations of most constituents detected in groundwater samples from REDSAC were below drinking-water thresholds. Volatile organic compounds (VOC) and pesticides were detected in less than one-quarter of the samples and were generally less than a hundredth of any health-based thresholds. NDMA was detected in one grid well above the NL-CA. Concentrations of all nutrients and trace elements in samples from REDSAC wells were below the health-based thresholds except those of arsenic in three samples, which were above the USEPA maximum contaminant level (MCL-US). However, none of these wells were public-supply wells. Concentrations of all radioactive constituents were below health-based thresholds except radon-222, which was detected above the proposed MCL-US of 300 pCi/L in samples from 11 grid wells. Most of the samples from REDSAC wells had concentrations of major elements, total dissolved solids, and trace elements below the non-enforceable thresholds set for aesthetic or technical concerns. A few samples contained iron, manganese, or pH at levels above the SMCL-CA or SMCL-US thresholds.

California↗
USGS2009

Groundwater-quality data in the Madera-Chowchilla study unit, 2008: Results from the California GAMA Program

Groundwater quality in the approximately 860-square-mile Madera–Chowchilla study unit (MADCHOW) was investigated in April and May 2008 as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Project was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The study was designed to provide a spatially unbiased assessment of the quality of raw groundwater used for public water supplies within MADCHOW, and to facilitate statistically consistent comparisons of groundwater quality throughout California. Samples were collected from 35 wells in Madera, Merced, and Fresno Counties. Thirty of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study area (grid wells), and five more were selected to provide additional sampling density to aid in understanding processes affecting groundwater quality (flow-path wells). Detection summaries in the text and tables are given for grid wells only, to avoid over-representation of the water quality in areas adjacent to flow-path wells. Groundwater samples were analyzed for a large number of synthetic organic constituents (volatile organic compounds [VOCs], low-level 1,2-dibromo-3-chloropropane [DBCP] and 1,2-dibromoethane [EDB], pesticides and pesticide degradates, polar pesticides and metabolites, and pharmaceutical compounds), constituents of special interest (N-nitrosodimethylamine [NDMA], perchlorate, and low-level 1,2,3-trichloropropane [1,2,3-TCP]), naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), and radioactive constituents (uranium isotopes, and gross alpha and gross beta particle activities). Naturally occurring isotopes and geochemical tracers (stable isotopes of hydrogen, oxygen, and carbon, and activities of tritium and carbon-14), and dissolved noble gases also were measured to help identify the sources and ages of the sampled groundwater. In total, approximately 300 constituents and field water-quality indicators were investigated. Three types of quality-control samples (blanks, replicates, and samples for matrix spikes) each were collected at approximately 11 percent of the wells sampled for each analysis, and the results obtained from these samples were used to evaluate the quality of the data for the groundwater samples. Field blanks rarely contained detectable concentrations of any constituent, suggesting that data for the groundwater samples were not compromised by possible contamination during sample collection, handling or analysis. Differences between replicate samples were within acceptable ranges. Matrix spike recoveries were within acceptable ranges for most compounds. This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, raw groundwater typically is treated, disinfected, or blended with other waters to maintain water quality. Regulatory thresholds apply to water that is served to the consumer, not to raw groundwater. However, to provide some context for the results, concentrations of constituents measured in the raw groundwater were compared with regulatory and non-regulatory health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and the California Department of Public Health (CDPH), and with aesthetic and technical thresholds established by CDPH. Comparisons between data collected for this study and drinking-water thresholds are for illustrative purposes only, and are not indicative of compliance or non-compliance with regulatory thresholds. The concentrations of most constituents detected in groundwater samples from MADCHOW wells were below drinking-water thresholds. Organic compounds (VOCs and pesticides) were detected in about 40 percent of the samples from grid wells, and most concentrations were less than 1/100 of regulatory or non-regulatory health-based thresholds, although the concentrations of low-level DBCP in 10 percent and low-level EDB in 3 percent of the samples from grid wells were above the corresponding USEPA maximum contaminant levels (MCL-USs). Perchlorate was detected in 70 percent of the samples from grid wells, and most concentrations were less than one-tenth of the CDPH maximum contaminant level (MCL-CA). Low-level 1,2,3-TCP was detected in 33 percent of the samples from grid wells, and all concentrations were less than 1/1,000 of the USEPA lifetime health advisory level (HAL-US). Most concentrations of trace elements and nutrients in samples were below regulatory and non-regulatory health-based thresholds. Concentrations were above the MCL-US for nitrate in 7 percent of the samples from grid wells, for arsenic and uranium in 13 percent each of the samples from grid wells; and the concentration of vanadium was above the CDPH notification level (NL–CA) in 3 percent of the samples from grid wells. Detections of radioactive constituents were below regulatory and non-regulatory health-based thresholds in most samples. Combined activities of uranium isotopes were detected above the MCL-CA in 20 percent of the subset of 25 grid well samples analyzed, and gross alpha particle activity was detected above the MCL-US in 20 percent of the samples from the 30 total grid wells. Most of the samples from MADCHOW grid wells had concentrations of major and minor ions, total dissolved solids, and trace elements below the CDPH secondary maximum contaminant levels (SMCL-CAs), which are nonenforceable thresholds set for aesthetic and technical concerns. Twenty percent of the samples from grid wells contained specific-conductance values, or concentrations of chloride, total dissolved solids, or manganese above the respective SMCL–CAs.

California↗
USGS2009

Groundwater-quality data in the Antelope Valley study unit, 2008: Results from the California GAMA Program

Groundwater quality in the approximately 1,600 square-mile Antelope Valley study unit (ANT) was investigated from January to April 2008 as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Project was developed in response to the Groundwater Quality Monitoring Act of 2001, and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The study was designed to provide a spatially unbiased assessment of the quality of raw groundwater used for public water supplies within ANT, and to facilitate statistically consistent comparisons of groundwater quality throughout California. Samples were collected from 57 wells in Kern, Los Angeles, and San Bernardino Counties. Fifty-six of the wells were selected using a spatially distributed, randomized, grid-based method to provide statistical representation of the study area (grid wells), and one additional well was selected to aid in evaluation of specific water-quality issues (understanding well). The groundwater samples were analyzed for a large number of organic constituents (volatile organic compounds [VOCs], gasoline additives and degradates, pesticides and pesticide degradates, fumigants, and pharmaceutical compounds), constituents of special interest (perchlorate, N-nitrosodimethylamine [NDMA], and 1,2,3-trichloropropane [1,2,3-TCP]), naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), and radioactive constituents (gross alpha and gross beta radioactivity, radium isotopes, and radon-222). Naturally occurring isotopes (strontium, tritium, and carbon-14, and stable isotopes of hydrogen and oxygen in water), and dissolved noble gases also were measured to help identify the sources and ages of the sampled groundwater. In total, 239 constituents and water-quality indicators (field parameters) were investigated. Quality-control samples (blanks, replicates, and samples for matrix spikes) were collected at 12 percent of the wells, and the results for these samples were used to evaluate the quality of the data for the groundwater samples. Field blanks rarely contained detectable concentrations of any constituent, suggesting that contamination was not a noticeable source of bias in the data for the groundwater samples. Differences between replicate samples generally were within acceptable ranges, indicating acceptably low variability. Matrix spike recoveries were within acceptable ranges for most compoundsThis study did not evaluate the quality of water delivered to consumers; after withdrawal from the ground, water typically is treated, disinfected, or blended with other waters to maintain water quality. Regulatory thresholds apply to water that is served to the consumer, not to raw groundwater. However, to provide some context for the results, concentrations of constituents measured in the raw groundwater were compared with regulatory and non-regulatory health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and California Department of Public Health (CDPH) and thresholds established for aesthetic concerns (secondary maximum contaminant levels, SMCL-CA) by CDPH. Comparisons between data collected for this study and drinking-water thresholds are for illustrative purposes only, and are not indicative of compliance or non-compliance with drinking water standards. Most constituents that were detected in groundwater samples were found at concentrations below drinking-water thresholds. Volatile organic compounds (VOCs) were detected in about one-half of the samples and pesticides detected in about one-third of the samples; all detections of these constituents were below health-based thresholds. Most detections of trace elements and nutrients in samples from ANT wells were below health-based thresholds. Exceptions include: one detection of nitrite plus nitrate as nitrogen (NO 2 +NO 3 ) above the USEPA maximum contaminant level (MCL-US: 10 mg/L), five detections of arsenic above the MCL-US (6 μg/L), one detection of boron above the CDPH notification level (NL-CA: 1,000 μg/L), and two detections of vanadium above the NL-CA (50 μg/L). Most detections of radioactive constituents were below health-based thresholds. Exceptions include two detections of gross alpha radioactivity (72-hour and 30-day counts) above the MCL-US (15 pCi/L). Also, radon-222 was detected above the proposed MCL-US (300 pCi/L) in 14 grid wells and the understanding well, but no wells had detections above the proposed alternative MCL-US (4,000 pCi/L). Most of the samples from ANT wells had concentrations of major elements, total dissolved solids (TDS), and trace elements below the non-enforceable thresholds set for aesthetic concerns. Three samples contained sulfate and four samples contained total dissolved solids at concentrations above the SMCL-CA thresholds (250 mg/L and 500 mg/L, respectively). Two of the total dissolved solids detections were above the upper SMCL-CA (1,000 mg/L). Samples from four wells had field pH values above the SMCL-US (>pH 8.5). Field-measured specific conductance values were above the SMCL-CA (900 μS/cm at 25°C) at eight wells with four of these measurements above the upper SMCL-CA threshold (1,600 μS/cm at 25°C).

California↗
USGS2008

Limestone - A Crucial and Versatile Industrial Mineral Commodity

Limestone, as used by the minerals industry, is any rock composed mostly of calcium carbonate (CaCO3). Although limestone is common in many parts of the United States, it is critically absent from some. Limestone is used to produce Portland cement, as aggregate in concrete and asphalt, and in an enormous array of other products, making it a truly versatile commodity. Portland cement is essential to the building industry, but despite our Nation's abundance of limestone, there have been cement shortages in recent years. These have been caused in part by a need to find new areas suitable for quarrying operations. To help manage our Nation's resources of such essential mineral commodities, the U.S. Geological Survey (USGS) provides crucial data and scientific information to industry, policymakers, and the public.

Fact Sheet↗
USGS2019

Baseline groundwater hydrology and water quality in and around Bluff, Utah

Southeastern Utah has a long history of oil and gas production. Two new hydrocarbon extraction wells have been proposed several miles northeast of the town of Bluff, Utah. In response to concern about the impacts of oil and gas extraction in the area on drinking-water quality, this study provides groundwater quality and hydrologic baseline data obtained before drilling the new hydrocarbon extraction wells. Data from future monitoring can be compared to these baseline water-quality data to identify changes in water quality. The quality of drinking water in Bluff is generally good, making changes in water quality more easily identifiable. Potential degradation of water quality from the proposed production wells could take hundreds to thousands of years to reach public-supply wells. Because of the limited water supply in this area, high-quality groundwater will continue to be an important resource into the foreseeable future.

Utah↗
USGS2020

Sediments and the sea floor of the continental shelves and coastal waters of the United States—About the usSEABED integrated sea-floor-characterization database, built with the dbSEABED processing system

Since the second half of the 20th century, there has been an increase in scientific interest, research effort, and information gathered on the geologic sedimentary character of the continental margins of the United States. Data and information from thousands of sources have increased our scientific understanding of the character of the margin surface, but rarely have those data been combined and integrated. Initially, the U.S. Geological Survey (USGS), in cooperation with the Institute of Arctic and Alpine Research at the University of Colorado Boulder, created the usSEABED database to provide surficial sea-floor-characterization data for USGS assessments of marine-based aggregates and for studies of sea-floor habitat. Since then, the USGS has continued to build up the database as a nationwide resource for many uses and applications. Previously published data derived from the usSEABED database have been released as three USGS data series publications containing data covering the U.S. Atlantic margin, the Gulf of Mexico and Caribbean regions, and the Pacific coast. An updated USGS data release unifies the three publications, incorporates additional data and sources including data from Alaska, Hawaii, and U.S. overseas territories, and provides revised output files that fix known errors and add known or inferred sampling dates. This report accompanies the data release and contains information on the methodology and products of the usSEABED database.

Open-File Report↗
USGS1988

U.S. Geological Survey ground-water studies in Nevada

Groundwater is an important natural resource in Nevada. In 1985, groundwater provided 24% of the total water withdrawn, and supplied about 40% of the State 's population. Public supply and self-supplied domestic use accounted for about 12% of the groundwater withdrawn, and self-supplied industrial and mining use was about 3%. The major issues related to groundwater in Nevada are: groundwater availability; natural and artificial groundwater recharge; underground storage of hazardous wastes; organic and inorganic trace constituents in groundwater; and geothermal groundwater systems. The U.S. Geological Survey (USGS) is actively conducting 30 hydrologic investigations in Nevada, of which 18 are related to groundwater quantity and quality. Three examples of ongoing groundwater studies by the USGS that are designed to address specific groundwater issues in Nevada are discussed: carbonate-rock aquifers in eastern and southern Nevada; groundwater quality in the Carson River basin, Nevada-California; and groundwater in Honey Lake Valley, Nevada-California. (Lantz-PTT)

Open-File Report↗