Environmental Monitoring Commons^™

Potential Aquifer Vulnerability In Regions Down-Gradient From Uranium In Situ Recovery (Isr) Sites, James A. Saunders, Bruce E. Pivetz, Nathan Voorhies, Richard T. Wilkin

United States Environmental Protection Agency: Publications

Sandstone-hosted roll-front uranium ore deposits originate when U(VI) dissolved in groundwater is reduced and precipitated as insoluble U(IV) minerals. Groundwater redox geochemistry, aqueous complexation, and solute migration are important in leaching uranium from source rocks and transporting it in low concentrations to a chemical redox interface where it is deposited in an ore zone typically containing the uranium minerals uraninite, pitchblende, and/or coffinite; various iron sulfides; native selenium; clays; and calcite. In situ recovery (ISR) of uranium ores is a process of contacting the uranium mineral deposit with leaching and oxidizing (lixiviant) fluids via injection of the lixiviant into wells …

Identification Of Putative Geographically Isolated Wetlands Of The Conterminous United States, Charles R. Lane, Ellen D'Amico

United States Environmental Protection Agency: Publications

Geographically isolated wetlands (GIWs) are wetlands completely surrounded by uplands. While common throughout the United States (U.S.), there have heretofore been no nationally available, spatially explicit estimates of GIW extent, complicating efforts to understand the myriad biogeochemical, hydrological, and habitat functions of GIWs and hampering conservation and management efforts at local, state, and national scales. We used a 10-m geospatial buffer as a proxy for hydrological or ecological connectivity of National Wetlands Inventory palustrine and lacustrine wetland systems to nationally mapped and available stream, river, and lake data. We identified over 8.3 million putative GIWs across the conterminous U.S., encompassing …

Water Consumption Estimates Of The Biodiesel Process In The Us, Qingshi Tu, Mingming Lu, Y. Jeffrey Yang, Don Scott

United States Environmental Protection Agency: Publications

As a renewable alternative to petroleum diesel, biodiesel has been widely used in the US and the world. However, its potential impact on water resources has not been much evaluated. This study investigates water consumption from the biodiesel process, which includes three stages: soybean irrigation, soybean-to-soybean oil processing, and biodiesel manufacturing, at both national and state levels. Mass-based allocation is performed and water consumption at the three stages is obtained on the basis of million gallons per year and gallon water per gallon biodiesel (gal/gal). The normalized water consumption (water intensity) of the irrigation, oil processing, and biodiesel production stages …

Quantitative Structure–Mesothelioma Potency Model Optimization For Complex Mixtures Of Elongated Particles In Rat Pleura: A Retrospective Study, Philip M. Cook, Joseph Swintek, Timothy D. Dawson, David Chapman, Mathew A. Etterson, Dale Hoff

United States Environmental Protection Agency: Publications

Cancer potencies of mineral and synthetic elongated particle mixtures, including asbestos fibers, are influenced by changes in fiber dose composition, bioavailability, and biodurability in combination with relevant cytotoxic dose-response relationships. An extensive rat intrapleural dose characterization data set with a wide variety of elongated particles physicochemical properties facilitated statistical analyses of pleural mesothelioma response data combined from several studies for evaluation of alternative dose-response models. Utilizing logistic regression of individual elongated particle dimensional variations within each test sample, four major findings emerged: (1) Mild acid leaching provides superior prediction of tumor incidence compared to samples that were not leached; (2) …

Quantitative Structure–Mesothelioma Potency Model Optimization For Complex Mixtures Of Elongated Particles In Rat Pleura: A Retrospective Study, Philip M. Cook, Joseph Swintek, Timothy D. Dawson, David Chapman, Mathew A. Etterson, Dale Hoff

United States Environmental Protection Agency: Publications

Cancer potencies of mineral and synthetic elongated particle mixtures, including asbestos fibers, are influenced by changes in fiber dose composition, bioavailability, and biodurability in combination with relevant cytotoxic dose-response relationships. An extensive rat intrapleural dose characterization data set with a wide variety of elongated particles physicochemical properties facilitated statistical analyses of pleural mesothelioma response data combined from several studies for evaluation of alternative dose-response models. Utilizing logistic regression of individual elongated particle dimensional variations within each test sample, four major findings emerged: (1) Mild acid leaching provides superior prediction of tumor incidence compared to samples that were not leached; (2) …

Impact Of Natural Organic Matter On Particle Behavior And Phototoxicity Of Titanium Dioxide Nanoparticles, Shibin Li, Hongbo Ma, Lindsay K. Wallis, Matthew A. Etterson, Benjamin Riley, Dale J. Hoff, Stephen A. Diamond

United States Environmental Protection Agency: Publications

Due to their inherent phototoxicity and inevitable environmental release, titanium dioxide nanoparticles (nano- TiO₂) are increasingly studied in the field of aquatic toxicology. One of the particular interests is the interactions between nano-TiO₂ and natural organic matter (NOM). In this study, a series of experiments was conducted to study the impacts of Suwannee River natural organic matter (SRNOM) on phototoxicity and particle behaviors of nano-TiO₂. For Daphnia magna, after the addition of 5 mg/L SRNOM, LC50 value decreased significantly from 1.03 (0.89–1.20) mg/L to 0.26 (0.22–0.31) mg/L. For zebrafish larvae, phototoxic LC50 values were …

Regional Scale Cropland Carbon Budgets: Evaluating A Geospatial Agricultural Modeling System Using Inventory Data, Xuesong Zhang, Roberto C. Izaurralde, David H. Manowitz, Ritvik Sahajpal, Tristram O. West, Allison M. Thomson, Min Xu, Kaiguang Zhao, Stephen D. Leduc, Jimmy R. Williams

United States Environmental Protection Agency: Publications

Accurate quantification and clear understanding of regional scale cropland carbon (C) cycling is critical for designing effective policies and management practices that can contribute toward stabilizing atmospheric CO₂ concentrations. However, extrapolating site-scale observations to regional scales represents a major challenge confronting the agricultural modeling community. This study introduces a novel geospatial agricultural modeling system (GAMS) exploring the integration of the mechanistic Environmental Policy Integrated Climate model, spatially-resolved data, surveyed management data, and supercomputing functions for cropland C budgets estimates. This modeling system creates spatiallyexplicit modeling units at a spatial resolution consistent with remotely-sensed crop identification and assigns cropping systems …

Esterification Pretreatment Of Free Fatty Acid In Biodiesel Production, From Laboratory To Industry, Ming Chai, Qingshi Tu, Jeffrey Y. Yang, Mingming Lu

United States Environmental Protection Agency: Publications

In the United States, biodiesel producers usually follow the 19.8:1 methanol-to-FFA molar ratio for free fatty acid (FFA) esterification, as suggested by the National Renewable Energy Laboratory (NREL) without optimization studies. In this paper, both laboratory studies and industrial practices of the esterification process were compared, and an optimization study of a used vegetable oil with 5% FFA was conducted. The optimal conditions of this oil, i.e., methanol-to-FFA molar ratio of 40:1, and sulfuric acid usage of 10%, fell out of the suggested range of 19.8:1. The activation energy of the esterification reaction is 20.7 kJ/mol at the optimized condition …

Bringing Resilience To Wildlife Management And Biodiversity Protection, Melinda Harm Benson, Matthew E. Hopton

United States Environmental Protection Agency: Publications

Biological diversity can be considered both temporally (Le., evolutionary time) and/or spatially and reflects the number, variety, and variability of organisms. It includes diversity within species (Le., genetic and morphological), between species (Le., alpha and beta), and among ecosystems (Le., beta and gamma). Over the past few hundred years, human activities have increased species extinction rates by as much as 1,000 times above the background rates that were typical over Earth's history (Figure 2.1) (Millennium Ecosystem Assessment 2005; but see He and Hubbell 2011). In the United States, there are approximately 1,900 species listed as threatened or endangered, with potentially …

Selecting Surrogate Endpoints For Estimating Pesticide Effects On Avian Reproductive Success, Richard S. Bennett, Matthew A. Etterson

United States Environmental Protection Agency: Publications

A Markov chain nest productivity model (MCnest) has been developed for projecting the effects of a specific pesticide‐use scenario on the annual reproductive success of avian species of concern. A critical element in MCnest is the use of surrogate endpoints, defined as measured endpoints from avian toxicity tests that represent specific types of effects possible in field populations at specific phases of a nesting attempt. In this article, we discuss the attributes of surrogate endpoints and provide guidance for selecting surrogates from existing avian laboratory tests as well as other possible sources.We also discuss some of the assumptions and uncertainties …

Exposure And Effects Of Perfluoroalkyl Substances In Tree Swallows Nesting In Minnesota And Wisconsin, Usa, Christine M. Custer, Thomas W. Custer, Paul M. Dummer, Matthew A. Etterson, Wayne E. Thogmartin, Qian Wu, Kurunthachalam Kannan, Annette Trowbridge, Patrick C. Mckann

United States Environmental Protection Agency: Publications

The exposure and effects of perfluoroalkyl substances (PFASs) were studied at eight locations in Minnesota and Wisconsin between 2007 and 2011 using tree swallows (Tachycineta bicolor). Concentrations of PFASs were quantified as were reproductive success end points. The sample egg method was used wherein an egg sample is collected, and the hatching success of the remaining eggs in the nest is assessed. The association between PFAS exposure and reproductive success was assessed by site comparisons, logistic regression analysis, and multistate modeling, a technique not previously used in this context. There was a negative association between concentrations of perfluorooctane …

Exposure And Effects Of Perfluoroalkyl Substances In Tree Swallows Nesting In Minnesota And Wisconsin, Usa, Christine M. Custer, Thomas W. Custer, Paul M. Dummer, Matthew A. Etterson, Wayne E. Thogmartin, Qian Wu, Kurunthachalam Kannan, Annette Trowbridge, Patrick C. Mckann

United States Environmental Protection Agency: Publications

The exposure and effects of perfluoroalkyl substances (PFASs) were studied at eight locations in Minnesota and Wisconsin between 2007 and 2011 using tree swallows (Tachycineta bicolor). Concentrations of PFASs were quantified as were reproductive success end points. The sample egg method was used wherein an egg sample is collected, and the hatching success of the remaining eggs in the nest is assessed. The association between PFAS exposure and reproductive success was assessed by site comparisons, logistic regression analysis, and multistate modeling, a technique not previously used in this context. There was a negative association between concentrations of perfluorooctane …

Molecular Detection Of Campylobacter Spp. And Fecal Indicator Bacteria During The Northern Migration Of Sandhill Cranes (Grus Canadensis) At The Central Platte River, Jingrang Lu, Hodon Ryu, Jason R. Vogel, Jorge Santo Domingo, Nicholas J. Ashbolt

United States Environmental Protection Agency: Publications

The risk to human health of the annual sandhill crane (Grus canadensis) migration through Nebraska, which is thought to be a major source of fecal pollution of the central Platte River, is unknown. To better understand potential risks, the presence of Campylobacter species and three fecal indicator bacterial groups (Enterococcus spp., Escherichia coli, and Bacteroidetes) was assayed by PCR from crane excreta and water samples collected during their stopover at the Platte River, Nebraska, in 2010. Genus-specific PCR assays and sequence analyses identified Campylobacter jejuni as the predominant Campylobacter species in sandhill crane excreta. Campylobacter …

Quantifying The Effects Of Pesticide Exposure On Annual Reproductive Success Of Birds, Matthew A. Etterson, Richard S. Bennett

United States Environmental Protection Agency: Publications

The Markov chain nest productivity model (MCnest) was developed for quantifying the effects of specific pesticide‐use scenarios on the annual reproductive success of simulated populations of birds. Each nesting attempt is divided into a series of discrete phases (e.g., egg laying, incubation, nestling rearing), and results from avian toxicity tests are used to represent the types of effects possible in the field during each breeding phase. The expected exposure dose each day throughout the breeding season can be compared to the toxicity thresholds assigned to each breeding phase to determine whether the nest attempt is at risk. The primary output …

Hidden Markov Models For Estimating Animal Mortality From Anthropogenic Hazards, Matthew A. Etterson

United States Environmental Protection Agency: Publications

Carcass searches are a common method for studying the risk of anthropogenic hazards to wildlife, including nontarget poisoning and collisions with anthropogenic structures. Typically, numbers of carcasses found must be corrected for scavenging rates and imperfect detection. Parameters for these processes (scavenging and detection) are often estimated using carcass distribution trials in which researchers place carcasses in the field at known times and locations. In this manuscript I develop a variety of estimators based on multi-event or hidden Markov models for use under different experimental conditions. I apply the estimators to two case studies of avian mortality, one from pesticide …

Comparison Of Pcr And Quantitative Real-Time Pcr Methods For The Characterization Of Ruminant And Cattle Fecal Pollution Sources, Meredith R. Raith, Catherine A. Kelty, John F. Griffith, Alexander Schriewer, Stefan Wuertz, Sophie Mieszkin, Michele Gourmelon, Georg H. Reischer, Andreas H. Farnleitner, Jared S. Ervin, Patricia A. Holden, Darcy L. Ebentier, Jennifer A. Jay, Dan Wang, Alexandria B. Boehm, Tiong Gim Aw, Joan B. Rose, E. Balleste, W.G. Meijer, Mano Sivaganesan, Orin C. Shanks

United States Environmental Protection Agency: Publications

The State of California has mandated the preparation of a guidance document on the application of fecal source identification methods for recreational water quality management. California contains the fifth highest population of cattle in the United States, making the inclusion of cow-associated methods a logical choice. Because the performance of these methods has been shown to change based on geography and/or local animal feeding practices, laboratory comparisons are needed to determine which assays are best suited for implementation. We describe the performance characterization of two end-point PCR assays (CF128 and CF193) and five real-time quantitative PCR (qPCR) assays (Rum2Bac, BacR, …

Fumigation Of A Laboratory-Scale Hvac System With Hydrogen Peroxide For Decontamination Following A Biological Contamination Incident, K. M. Meyer, M. W. Calfee, J. P. Wood, L. Michelsen, B. Attwood, M. Clayton, A. Touati, R. Delafield

United States Environmental Protection Agency: Publications

Aims

To evaluate hydrogen peroxide vapor (H₂O₂) for its ability to inactivate Bacillus spores within a laboratory-scale heating, ventilation and air-conditioning (HVAC) duct system.

Methods and Results

Experiments were conducted in a closed-loop duct system, constructed of either internally lined or unlined galvanized metal. Bacterial spores were aerosol-deposited onto 18-mm-diameter test material coupons and strategically placed at several locations within the duct environment. Various concentrations of H₂O₂ and exposure times were evaluated to determine the sporicidal efficacy and minimum exposure needed for decontamination. For the unlined duct, high variability was observed in the …

Seasonal Dimorphism In The Horny Bills Of Sparrows, Russell Greenberg, Matthew Etterson, Raymond M. Danner

United States Environmental Protection Agency: Publications

Bill size is often viewed as a species-specific adaptation for feeding, but it sometimes varies between sexes, suggesting that sexual selection or intersexual competition may also be important. Hypotheses to explain sexual dimorphism in avian bill size include divergence in feeding niche or thermoregulatory demands, intrasexual selection based on increased competition among males, or female preference. Birds also show seasonal changes in bill size due to shifts in the balance between growth rate and wear, which may be due to diet or endogenous rhythms in growth. Insight into the function of dimorphism can be gained using the novel approach of …

Assessing Population-Level Effects Of Zinc Exposure To Brown Trout (Salmo Trutta) In The Arkansas River At Leadville, Colorado, John Toll, Kristina Garber, David Deforest, William Brattin

United States Environmental Protection Agency: Publications

We assessed population-level risk to upper Arkansas River brown trout (Salmo trutta L.) due to juvenile exposure to Zn. During spring, individuals in the sensitive young-of-the-year life stage are exposed to elevated Zn concentrations from acid mine drainage. We built and used a simple life-history population model for the risk assessment, with survival and fecundity parameter values drawn from published data on brown trout populations located in the United States and Europe. From experimental data, we derived a toxicity model to predict mortality in brown trout fry after chronic exposure to Zn. We tested sensitivity of risk estimates to …

Nebraska - Epa Map Of Radon Zones, Us Environmental Protection Agency

United States Environmental Protection Agency: Publications

The purpose of this map is to assist National, State and local organizations to target their resources and to implement radon-resistant building codes.

This map is not intended to determine if a home in a given zone should be tested for radon. Homes with elevated levels of radon have been found in all three zones.

All homes should be tested, regardless of zone designation.

Development And Evaluation Of A Quantitative Pcr Assay Targeting Sandhill Crane (Grus Canadensis) Fecal Pollution, Hodon Ryu, Jingrang Lu, Jason Vogel, Michael Elk, Felipe Chávez-Ramírez, Nicholas Ashbolt, Jorge Santo Domingo

United States Environmental Protection Agency: Publications

While the microbial water quality in the Platte River is seasonally impacted by excreta from migrating cranes, there are no methods available to study crane fecal contamination. Here we characterized microbial populations in crane feces using phylogenetic analysis of 16S rRNA gene fecal clone libraries. Using these sequences, a novel crane quantitative PCR (Crane1) assay was developed, and its applicability as a microbial source tracking (MST) assay was evaluated by determining its host specificity and detection ability in environmental waters. Bacteria from crane excreta were dominated by bacilli and proteobacteria, with a notable paucity of sequences homologous to Bacteroidetes and …

Active Pharmaceutical Ingredients And Aquatic Organisms, Christian G. Daughton, Bryan W. Brooks

United States Environmental Protection Agency: Publications

The presence of active pharmaceuticals ingredients (APIs) in aquatic systems has led in recent years to a burgeoning literature examining environmental occurrence, fate, effects, risk assessment, and treatability of these compounds. The vast preponderance of studies aimed at identifying and quantifying contaminant residues in aquatic tissues have involved the conventional and legacy pollutants. Comparatively few studies have been targeted at APIs, primarily those that are lipophilic. Although APIs have received much attention as "emerging" contaminants of concern, it is important to recognize that traditional approaches to understand and predict exposure and effects of other environmental organic contaminant classes mayor may …

Partially Acetylated Sugarcane Bagasse For Wicking Oil From Contaminated Wetlands, Seungoon Chung, Makram T. Suidan, Albert D. Venosa

United States Environmental Protection Agency: Publications

Sugarcane bagasse was partially acetylated to enhance its oil-wicking ability in saturated environments while holding moisture for hydrocarbon biodegradation. The water sorption capacity of raw bagasse was reduced fourfold after treatment, which indicated considerably increased hydrophobicity but not a limited capability to hold moisture for hydrocarbon biodegradation. Characterization results by Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), X-ray diffraction (XRD), and surface area analyzer suggested that treated bagasse exhibited enhanced hydrophobicity and surface area. Oil wicking test results indicate that treated bagasse is more effective in wicking oil from highly saturated environments than raw bagasse and suggest that application …

Time-Lapse Three-Dimensional Inversion Of Complex Conductivity Data Using An Active Time Constrained (Atc) Approach, M. Karaoulis, A. Revil, D. D. Werkema, B. J. Minsley, W. F. Woodruff, A. Kemna

United States Environmental Protection Agency: Publications

Induced polarization (more precisely the magnitude and phase of impedance of the subsurface) is measured using a network of electrodes located at the ground surface or in boreholes. This method yields important information related to the distribution of permeability and contaminants in the shallow subsurface. We propose a new time-lapse 3-D modelling and inversion algorithm to image the evolution of complex conductivity over time.We discretize the subsurface using hexahedron cells. Each cell is assigned a complex resistivity or conductivity value. Using the finite-element approach, we model the in-phase and out-of-phase (quadrature) electrical potentials on the 3-D grid, which are then …

Ddt And Other Organohalogen Pesticides In Aquatic Organisms, Nancy Beckvar, Guilherme R. Lotufo

United States Environmental Protection Agency: Publications

Organohalogen (OH) compounds are persistent hydrocarbon compounds containing a halogen group, often chlorine or bromine, that substitutes for hydrogen atoms in different positions in the hydrocarbon. They may occur naturally, but this chapter's focus is on synthetically produced compounds, mainly organochlorines, that were produced for use as pesticides. Nine OH compounds (aldrin, chlordane, dichlorodiphenyltrichloroethane [DDT], dieldrin, endrin, heptachlor, hexachlorobenzene, mirex, and toxaphene) are in the top 12 list of particularly toxic and persistent organic pollutants (POPs) identified by the Stockholm Convention treaty implemented in 2004 under the United Nations Environment Program (UNEP). More than 90 countries have signed on to …

Adverse Outcome Pathways And Ecological Risk Assessment: Bridging To Population-Level Effects, Vincent J. Kramer, Matthew A. Etterson, Markus Hecker, Cheryl A. Murphy, Guritno Roesijadi, Daniel J. Spade, Julann A. Spromberg, Magnus Wang, Gerald T. Ankley

United States Environmental Protection Agency: Publications

Maintaining the viability of populations of plants and animals is a key focus for environmental regulation. Population-level responses integrate the cumulative effects of chemical stressors on individuals as those individuals interact with and are affected by their conspecifics, competitors, predators, prey, habitat, and other biotic and abiotic factors. Models of population-level effects of contaminants can integrate information from lower levels of biological organization and feed that information into higher-level community and ecosystem models. As individual-level endpoints are used to predict population responses, this requires that biological responses at lower levels of organization be translated into a form that is usable …

A New Process For Organizing Assessments Of Social, Economic, And Environmental Outcomes: Case Study Of Wildland Fire Management In The Usa, Randall Jf Bruins, Wayne R. Munns Jr., Stephen J. Botti, Steve Brink, David Cleland, Larry Kapustka, Danny Lee, Valerie Luzadis, Laura Falk Mccarthy, Naureen Rana, Douglas B. Rideout, Matt Rollins, Peter Woodbury, Mike Zupko

United States Environmental Protection Agency: Publications

Ecological risk assessments typically are organized using the processes of planning (a discussion among managers, stakeholders, and analysts to clarify ecosystem management goals and assessment scope) and problem formulation (evaluation of existing information to generate hypotheses about adverse ecological effects, select assessment endpoints, and develop an analysis plan). These processes require modification to be applicable for integrated assessments that evaluate ecosystem management alternatives in terms of their ecological, economic, and social consequences.We present 8 questions that define the steps of a new process we term integrated problem formulation (IPF), and we illustrate the use of IPF through a retrospective case …

Markov Chain Estimation Of Avian Seasonal Fecundity, Matthew A. Etterson, Richard S. Bennett, Eric L. Kershner, Jeffery W. Walk

United States Environmental Protection Agency: Publications

Avian seasonal fecundity is of interest from evolutionary, ecological, and conservation perspectives. However, direct estimation of seasonal fecundity is difficult, especially with multi-brooded birds, and models representing the renesting and quitting processes are usually required. To explore the consequences of modeling decisions on inference about avian seasonal fecundity, we generalize previous Markov chain (MC) models of avian nest success to formulate two different MC models of avian seasonal fecundity that represent two different ways to model renesting decisions and breeding cessation. We parameterize both Markov chains (regular and absorbing) for two species (Eastern Meadowlark, Sturnella magna, and Dickcissel, Spiza …

National Primary Drinking Water Regulations

United States Environmental Protection Agency: Publications

NOTES

1 Definitions

• Maximum Contaminant Level Goal (MCLG): The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety and are non-enforceable public health goals.

• Maximum Contaminant Level (MCL): The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to MCLGs as feasible using the best available treatment technology and taking cost into consideration. MCLs are enforceable standards.

• Maximum Residual Disinfectant Level Goal (MRDLG): The level of a drinking water disinfectant below which there is …

Estimating The Effects Of Detection Heterogeneity And Overdispersion On Trends Estimated From Avian Point Counts, Matthew A. Etterson, Gerald J. Niemi, Nicholas P. Danz

United States Environmental Protection Agency: Publications

Point counts are a common method for sampling avian distribution and abundance. Although methods for estimating detection probabilities are available, many analyses use raw counts and do not correct for detectability. We use a removal model of detection within an N-mixture approach to estimate abundance trends corrected for imperfect detection. We compare the corrected trend estimates to those estimated from raw counts for 16 species using 15 years of monitoring data on three national forests in the western Great Lakes, USA. We also tested the effects of overdispersion by modeling both counts and removal mixtures under three statistical distributions: …