|
|
|
Environmental Sciences Division Publications: 2008
 |
|
This page lists publication titles, citations and abstracts produced by NERL's Environmental Sciences Division for the year 2008, organized by Publication Type. Your search has returned
34 Matching Entries.
See also Environmental Sciences Division citations with abstracts:
1999,
2000,
2001,
2002,
2003,
2004,
2005,
2006,
2007,
2008
Technical Information Manager: Chris Sibert - (702) 798-2234 or sibert.christopher@epa.gov
|
| |
|
|
|
Presented/Published |
| COMMUNICATION PRODUCT |
Collaborative Research: Streamflow, Urban Riparian Zones, Bmps, and Impervious Surfaces |
02/29/2008
|
|
|
|
JARNAGIN, S. Collaborative Research: Streamflow, Urban Riparian Zones, Bmps, and Impervious Surfaces. EPA/600/F-08/001, 2008.
|
| Abstract:
|
The U.S. EPA Landscape Ecology Branch (LEB) in Research Triangle Park, North Carolina is currently conducting collaborative landscape/stream ecology research in the Clarksburg Special Protection Area (CSPA) in Montgomery County, Maryland. The CSPA subwatersheds are on the outer edge of the exurban development shockwave expanding outward from the Washington DC metropolitan area and are outlined in yellow on the upper-left of Figure 1. The CSPA is an area of rapid development that we expect will be built out within the next five to ten years. The Montgomery County Department of Environmental Protection (DEP) has been monitoring stream biology and chemistry in the area streams for a decade and the CSPA involves the use of best management practices (BMPs) that are designed to limit the impact of development on water resources.
|
|
| ETV DOCUMENT |
Use of Radio Frequency Identification (Rfid) for Tracking Hazardous Waste Shipments Across International Borders Test/QA Plan |
03/29/2008
|
|
|
|
VARNER, K. E. Use of Radio Frequency Identification (Rfid) for Tracking Hazardous Waste Shipments Across International Borders Test/QA Plan. EPA/600/R-08/027, 2008.
|
| Abstract:
|
The Environmental Technology Verification (ETV) – Environmental and
Sustainable Technology Evaluations (ESTE) Program conducts third-party verification testing of commercially available technologies that may accomplish environmental program management goals. In this verification testing project, radio frequency identification (RFID) systems will be evaluated in a unique application of the technology for tracking hazardous waste or hazardous material (HAZMAT) shipments from generator to receiver, across international borders. A stakeholder committee of vendors, buyers, users and federal agencies guided the development of this verification project plan to ensure that testing of the RFID systems is conducted under realistic conditions. This Test and Quality Assurance Project Plan (QAPP) describes the verification
program for evaluating RFID systems to track cross-border hazardous waste shipments. The document explains the program background, the experimental design and cross-border HAZMAT shipment scenarios, selected vendor approaches for RFID systems, methods and
evaluation criteria for testing vendors’ RFID systems, project quality assurance objectives, data review and management, health and safety, and security requirements for verification testing.
|
|
| JOURNAL |
Evaluation of Analytical Reporting Errors Generated as Described in Sw-846 Method 8261a |
04/15/2008
|
|
|
|
HIATT, M. H. Evaluation of Analytical Reporting Errors Generated as Described in Sw-846 Method 8261a. AMERICAN CHEMICAL SOCIETY. Springer-Verlag, Berlin, Germany, 13(4-5):247-254, (2008).
|
| Abstract:
|
SW-846 Method 8261A incorporates the vacuum distillation of analytes
from samples, and their recoveries are characterized by internal standards. The internal
standards measure recoveries with confidence intervals as functions of physical
properties. The frequency the calculated confidence intervals captured a known
concentration was very close to theoretical predictions. The ruggedness of the Method's
generation of confidence intervals was tested by analyzing water samples that were
altered using salt, glycerin, oil, and detergent as well as increasing sample volume size.
Quality control requirements were established for identifying when results might not be
normally distributed. There were 11,260 analyte results, of which 90.8% of the data
passed quality controls. Their distribution about true value was near theoretical values
(71.3, 95.0, and 99.2% for one, two and three sigma deviations).
|
|
| JOURNAL |
Assessing Vulnerabilities from Alternative Development Patterns |
07/03/2008
|
|
|
|
MEHAFFEY, M. H., L. WAINGER, T. G. WADE, D. YANKEE, E. R. SMITH, V. BOTT, AND R. YARBOURGH. Assessing Vulnerabilities from Alternative Development Patterns. LANDSCAPE AND URBAN PLANNING. Elsevier Science Ltd, New York, NY, 87(1):83-94, (2008).
|
| Abstract:
|
Planners in a rapidly urbanizing area must take into account trade offs between
multiple environmental issues of concern. A 15-county region centered on Charlotte, North
Carolina, is experiencing a boom in growth resulting in both air and water quality concerns. In
this paper, we examine changes to environmental and socio-economic factors across the region
between two contrasting alternative future scenarios of land use development. We compared
high and medium density growth scenarios and found that the high density scenario resulted in
improved landscape quality in most counties, as measured by a series of metrics. Those counties
not demonstrating county level differences between scenarios, Mecklenburg, NC and York, SC,
still had several watersheds within each county that were less vulnerable to habitat and water
quality impacts under the high density scenario. High density development achieved through
creation of distinct urban centers (compact centers scenario) was associated with higher
phosphorus and sediment loads in watersheds that contained the urban centers. In contrast, the
greater land consumption associated with the medium density scenario consumed nutrientgenerating
agricultural lands, resulting in lower nitrogen loading. Increased density was
estimated to generate lower expenditures for county governments, but also potentially lower
revenues if multi-unit houses are valued at current market rates, leading to overall less favorable
fiscal results with the high density scenario for all but the most urbanized county. We found that
incorporating spatial dynamics in our assessment of the region provided a way to evaluate future
patterns under different alternative growth scenarios. In addition, we found that by using two
different reporting units (e.g. regional and local), decisions on where to target development and
resources for maximizing benefits to both the economy and environment could be refined.
|
|
| JOURNAL |
Resource Managers Benefit from EPA's View of the Ozarks Landscape |
05/01/2008
|
|
|
|
LOPEZ, R. D., M. S. NASH, D. T. HEGGEM, AND D. W. EBERT. Resource Managers Benefit from EPA's View of the Ozarks Landscape. EM: AIR AND WASTE MANAGEMENT ASSOCIATIONS MAGAZINE FOR ENVIRONMENTAL MANAGERS. Air & Waste Management Association, Pittsburgh, PA, 58(5):20-21, (2008).
|
| Abstract:
|
The words “promise, praise, and problems” are frequently used to describe recent industry and population growth in the Ozark Mountains region (see, for example, Kirkpatrick, S. No Turning Back Now; Ozarks Magazine, 2007). The arrival of new jobs to the area has led to a doubling of the population to nearly 700,000 in the past 20 years. Though residents have enjoyed financial benefits from business expansion, there is increasing concern that this growth is jeopardizing the quality of life, including the availability of clean water. Many residents in the area believe that urbanization, loss of wilderness, increased traffic, and a strained infrastructure caused by economic development
have had a negative impact on water quality. Citizens, regulators, and resource managers alike recognize the need for watershed protection efforts to prevent adverse effects on human health and to preserve ecosystem benefits in the Ozarks.
|
|
| JOURNAL |
Metal Release from Bottom Sediments of Ocoee Lake No. 3, a Primary Catchment Area for the Ducktown Mining District |
04/30/2008
|
|
|
|
Lee, G., G. Faure, J. Bigham, AND D. J. WILLIAMS. Metal Release from Bottom Sediments of Ocoee Lake No. 3, a Primary Catchment Area for the Ducktown Mining District. JOURNAL OF ENVIRONMENTAL QUALITY. American Society of Agronomy, 37:344-352, (2008).
|
| Abstract:
|
Ocoee Lake No. 3 is the first reservoir receiving suspended
sediments contaminated with trace metals discharged by acid
mine effluents from the Ducktown Mining District, Tennessee.
Bottom sediments (0–5 cm) from the lake were sampled to
assess the potential for future adverse environmental effects
if no remediation controls or activities are implemented. The
sediments were found to include a major component (173
± 19 g kg−1) that dissolved in 6 mol L−1 HCl within 24 h.
This acid-soluble and relatively labile fraction contained high
concentrations of Fe (460 ± 40 g kg−1), Al (99 ± 11 g kg−1),
Mn (10 ± 8 g kg−1), Cu (2000 ± 700 mg kg−1), Zn (1300 ± 200
mg kg−1), and Pb (300 ± 200 mg kg−1). When the pH of water
in contact with the sediment was decreased experimentally
from 6.4 to 2.6, the concentrations of dissolved trace metals
increased by factors of 2200 for Pb, 160 for Cu, 21 for Zn, 9
for Cd, 8 for Ni, and 5 for Co. The order in which metals were
released with decreasing pH was the reverse of that reported for
pH-dependent sorption of these metals in upstream systems.
Substantial release of trace metals from the sediment was observed
even by a modest decrease of pH from 6.4 to 5.9. Therefore,
the metal-rich sediment of the lake should be considered as
potentially hazardous to bottom-dwelling aquatic species and
other organisms in the local food chain. In addition, if the
reservoir is dredged or if the dam is removed, the accumulated
sediment may have to be treated for recovery of sorbed metals.
|
|
| NON-EPA PUBLISHED PROCEEDINGS |
Historical Analysis of the Relationship of Streamflow Flashiness With Population Density, Imperviousness, and Percent Urban Land Cover in the Mid-Atlantic Region |
05/16/2008
|
|
|
|
JARNAGIN, S. Historical Analysis of the Relationship of Streamflow Flashiness With Population Density, Imperviousness, and Percent Urban Land Cover in the Mid-Atlantic Region. World Environmental & Water Resources Congress 2008, Honolulu, HI, May 12 - 16, 2008. JOURNAL OF THE HYDRAULICS DIVISON, ASCE. American Society of Civil Engineers (ASCE), Reston, VA 1-10, (2008).
|
| Abstract:
|
Historical US Census population data was used to estimate population
density for 1930-2000 and satellite imagery from circa 1973, 1992, and 2001 was used to estimate the degree of urban development and the percent imperviousness (for 1992 and 2001) for a set of 150 small
(< 130 km2) watersheds with long-term (> 20 years) USGS NWIS historical daily mean streamflow datasets in the mid-Atlantic, USA. The Richards-Baker Flashiness Index was used to calculate annual flashiness values and a seven-year-window mean stream flashiness value was calculated for each population/development estimation date. Streamflow stations that showed significant changes in historical flashiness had a higher mean population density than those that showed no change. The strength of the population-flashiness correlation increased as the spatial scale of the population estimator was reduced. Urban development and imperviousness estimators were equally effective at exploring the
relationship between stream flashiness and watershed development. Watersheds with less than 10% imperviousness and less than 20% 'urban development' displayed background levels of stream flashiness and mean flashiness increased with increasing
imperviousness and urban development density thereafter.
|
|
| PRESENTATION |
Automated Deconvolution of Composite Mass Spectra Obtained With An Open-Air Ionizations Source Based on Exact Masses and Relative Isotipic Abundances |
03/07/2008
|
|
|
|
GRANGE, A. H. AND G. SOVOCOOL. Automated Deconvolution of Composite Mass Spectra Obtained With An Open-Air Ionizations Source Based on Exact Masses and Relative Isotipic Abundances. Presented at 2008 Pittsburgh Conference, New Orleans, LA, March 01 - 07, 2008.
|
| Abstract:
|
Chemicals dispersed by accidental, deliberate, or weather-related events must be rapidly identified to assess health risks. Mass spectra from high levels of analytes obtained using rapid, open-air ionization by a Direct Analysis in Real Time (DART®) ion source often contain
precursor, oxide, adduct, and/or dimeric ions. Ion compositions must be determined and ion
correlations must be made to understand composite mass spectra and enhance confidence in
tentative identifications. These tasks are performed rapidly by an in-house Ion Correlation
Program (ICP) that considers exact masses and relative isotopic abundances measured by a JEOL
AccuTOF® time-of-flight mass spectrometer. ASCII files provided by the data system acquired
at three CID voltages are imported into the ICP. Possible precursor ions and related oxidized,
ammonium adducts, protonated dimers, and ammoniated dimers are found in the lowest CID
voltage mass spectrum. At the intermediate CID voltage, dimeric ions are fragmented, while
possible precursor ions remain and are confirmed as such. Product ions are gleaned from the
highest CID voltage spectrum. Starting with the highest-mass precursor ion, all lower-mass ions
that are not precursor ions are checked to see if they are precursor ion subunits. When multiple
compounds are present with different collections of heteroatoms, some will and some will not
correlate with each precursor ion. Examples of mass spectra deconvolution will be demonstrated
for data acquired with the DART/TOFMS.
|
|
| PRESENTATION |
Effects of the Variation of Select Sampling Parameters on Soil Vapor Concentrations |
05/22/2008
|
|
|
|
SCHUMACHER, B. A. AND J. H. ZIMMERMAN. Effects of the Variation of Select Sampling Parameters on Soil Vapor Concentrations. Presented at Remediation of Chlorinated and Recalcitrant Compounds: The Sixth International Conference, Monterey, CA, May 19 - 22, 2008.
|
| Abstract:
|
Currently soil vapor surveys are commonly used as a screening technique to delineate subsurface volatile organic compound (VOC) contaminant plumes and to provide information for vapor intrusion and contaminated site evaluations. To improve our understanding of the fate and transport of soil vapor containing VOCs, the U.S. EPA funded two research studies conducted at a site on Vandenberg Air Force Base (CA) contaminated with the chlorinated solvent TCE.
The first study evaluated the effect of variations in purge volume, sample flow rate, and sample volume during soil vapor sample collection. Sample purge volumes were varied from 1 to 4,400 system dead-space volumes. The effect of purge volume on the measured VOC concentrations was more pronounced than the effect of sample flow rate; however, this variability may not be significant in terms of site characterization. Sample flow rates were varied from 100 to 5000 cc/min with no significant effect on soil vapor concentrations. Sample volume was varied from 25 to 6,000 mL. The increase in purge volume from 25 to 1,000 mL resulted in an increase in VOC concentrations followed by a decrease in VOC concentrations in sample volumes greater than 1000 mL. The common use of the 6,000 mL sample size to decrease detection limits by EPA method TO-15 may result in artificially low sample analyte concentrations or non-detects.
The second study evaluated the correlation of temporal and shallow soil gas concentrations (4' to 17' bgs) variations over a six week period. Over 11,000 analyses were completed from thirteen sampling points by an automated analytical system. An on-site mobile weather station collected meteorological data during the sampling period. Analyte concentrations varied less than 20% during the sampling period resulting in no correlation for this set of data. No precipitation events occurred during this study.
|
|
| PRESENTATION |
Temporal Geophysical Investigations of the Ft-2-Plume at the Wurtsmith Air Force Base, Oscoda, Michigan |
04/10/2008
|
|
|
|
Vukenkeng, C., E. Atekwana, E. Atekwana, AND D. D. WERKEMA. Temporal Geophysical Investigations of the Ft-2-Plume at the Wurtsmith Air Force Base, Oscoda, Michigan. Presented at Symposium on the Application of Geophysics to Environmental and Engineering Problems, Philadelphia, PA, April 06 - 10, 2008.
|
| Abstract:
|
The decommissioned Wurtsmith Air Force Base former Fire Training Cell (FT-02) facility has been the focus of several geophysical investigations. After several decades of fire training exercises, significant amounts of hydrocarbons and some solvents seeped into the subsurface contaminating the vadose and saturated zones in the source
area. Groundwater geochemistry studies defined a contaminant plume that was approximately 125 m wide and > 300 m long. The boundary of the plume was further defined by using GPR, SP, and resistivity techniques. The source of the geophysical anomalies was attributed to biogeochemical modifications of the contaminated zone resulting from intrinsic bioremediation. In 2007, another integrated geophysical study of the site was conducted. GPR, SP, and electrical resistivity surveys were conducted with expectations of achieving similar results as the past investigations. However, there was a marked decrease in
geophysical response from all of our geophysical techniques. The GPR anomaly has migrated deeper into the subsurface, the positive SP response was significantly attenuated, and the conductive resistivity anomaly has been replaced by background resistivity values.
We attribute the attenuation of the observed geophysical anomalies to ongoing soil vapor extraction initiated in 2001. Significant removal of the contaminant mass by the vapor extraction system altered the subsurface biogeochemical conditions and these changes were documented by the 2007 geophysical data and geochemical data. The results of this study show that the attenuation of the contaminant plume is detectable with
both geophysical and geochemical methods.
|
|
| PRESENTATION |
Landscape Influences on Lake Chemisty of Small Dimictic Lakes in the Human Dominated Southern Wisconsin Landscape |
04/10/2008
|
|
|
|
ALLEN, P. Landscape Influences on Lake Chemisty of Small Dimictic Lakes in the Human Dominated Southern Wisconsin Landscape. Presented at IALE Conference, mADISON, WI, April 06 - 10, 2008.
|
| Abstract:
|
Changes in landscape heterogeneity, historic landcover change, and human disturbance regimes are governed by complex interrelated landscape processes that modify lake water quality through the addition of nutrients, sediment, anthropogenic chemicals, and changes in major ion concentrations. Current knowledge of how landscapes influence water resources comes primarily from stream studies. This study
contributes to the small but growing body of research on the landscape ecology of lakes. Twelve lakes, similar in most respects except for surrounding landuse and landscape position, were sampled over a two year period for water quality proxies of nutrient enrichment and productivity; erosion and sedimentation; solutes, and anthropogenic chemicals. Nonmetric multidimensional scaling was used to evaluate
how lakes varied across gradients of water and sediment chemistry and lake morphometry. Correlation and multiple regression analyses tested our assumptions (based on previous stream studies) about correlations between landuse and land cover; heterogeneity, and water quality proxies. Differences in chemistry among lakes were most correlated with lake depth which is related to landscape position and governed by geomorphology. These data show that in general, high proportions of forests and wetlands were correlated with desirable water quality characteristics (i.e. reduced sedimentation, nutrients and dissolved solids). Agriculture was positively correlated with nutrient enrichment and
productivity, erosion and sedimentation, increased solute concentrations, and atrazine. High landscape interspersion and increased edge densities were also correlated with increased solute concentrations. Decreased shape complexity of the patches (area weighted mean shape index) was positively correlated with reduced water quality and
agriculture. Water quality predictions based on landuse and landscape metrics were more often confirmed at larger (watershed) spatial scales. The affect of landscape position is a significant factor in interpreting impacts on lakes particularly at local scales and should be considered in future work. Results of this study suggest that landscape management goals for lake protection should include minimizing agriculture in riparian areas. Additionally, an increase in forest and wetland buffers at smaller (catchment and riparian) spatial scales,
and an increase in forest connectivity at watershed scales should enhance the natural cleansing functions of both forests and wetlands and improve or maintain lake water quality.
|
|
| PRESENTATION |
The Use of Modis Ndvi Data for Characterizing Cropland Across the Great Lakes Basin |
07/11/2008
|
|
|
|
LUNETTA, R. S. AND Y. Shao. The Use of Modis Ndvi Data for Characterizing Cropland Across the Great Lakes Basin. Presented at International Geoscience and REmotre Sensing Symposium, Boston, MA, July 07 - 11, 2008.
|
| Abstract:
|
The Moderate Resolution Imaging Spectroradiometer (MODIS) provides new opportunities for characterizing land-cover (LC) to support monitoring and assessment studies at watershed, regional and global scales. This research evaluated the potential for using the MODIS Normalized Difference Vegetation Index (NDVI) 16-day composite
250 m product (MOD13Q) time-series data to develop a cropland mask and identify four major crop types (corn, soybean, hay, and wheat), throughout the entire 480,000 km2 Great Lakes Basin (GLB). The objective of this research was to evaluate the impacts of
scale on the performance time-trajectory analytical approaches for LC classifications.
MODIS-NDVI data were first acquired from the USGS EROS Data Center for calendar year 2002 and subsequently preprocessed (anomalous data removed and replaces with estimated values), to provide a high quality uninterrupted data stream to support multi-temporal (phenology-based) analysis. LC classifications were then performed for the entire GLB (n=1) and for individual GLB ecoregions (n=11). For the
GLB scale analysis, training samples of agricultural and non-agricultural land were collected across the entire area to support a single regional scale classification. In the latter approach (ecoregion-stratified), the GLB was first stratified into 11 ecoregions and both the training sample collections and classifications were conducted on an individual
basis for each ecological unit. Landsat panchromatic imageries from 2000−2002 were used as the primary reference datasets for identifying training samples. Also, a variety of image classification algorithms were examined, including (i) supervised statistical classification, (ii) principle component analysis, and (iii) non-parametric techniques such
as neural networks and decision tree. A validation of 2002 NDVI-derived crop mask was conducted using both a pixelwise and county-aggregated approaches. For the pixel-wise accuracy assessment, testing sites were generated using a stratified random sample approach. The testing sites were visually interpreted from Landsat panchromatic images. Addition, the agricultural pixels
derived from NDVI image were aggregated to the county level and compared to statistics from the National Agricultural Statistics Service (NASS). The pixel-level and countylevel comparisons provided a multi-level accuracy assessment. The crop mask with the
highest accuracy was used as a baseline dataset for subsequent classification of individual crop types. The agricultural lands were classified into five major crop types (corn, hay, soybean, wheat, and other) using three classification algorithms; which were evaluated
using the county level agricultural statistics to perform an accuracy assessment.
The results from this research indicated that the ecoregion-stratified approach generated superior crop mask compare to the GLB-wide classification. The stratification of the study area reduced the confusions between agricultural and non-agricultural pixels with regard to temporal and/or phenological information. Also, the accuracy assessments
results indicated that both neural network and decision tree classifiers performed better than a statistical maximum likelihood classifier. The primary reason was that neural networks and decision tree made no assumptions about the input data distribution and they are also less sensitive to the correlations among input features. Due to the lack of
reference data, no pixel-wise accuracy assessment was conducted for individual crop identification (i.e., corn, hay, soybean, and wheat), however, the accuracies of crop acreage estimates at county level were acceptable compare to the NASS agricultural statistics.
|
|
| PRESENTATION |
Spatial Patterns of Airborne Pesticides in the Alpine Habitate of a Declining California Amphibian, the Mountain Yellow-Legged Frog |
01/11/2008
|
|
|
|
BRADFORD, D. F., K. Stanley, L. McConnell, N. G. TALLENT-HALSELL, S. Simonich, AND R. Knapp. Spatial Patterns of Airborne Pesticides in the Alpine Habitate of a Declining California Amphibian, the Mountain Yellow-Legged Frog. Presented at California-Nevada Amphibian Populations Task Force Conference, San Diego, CA, January 10 - 11, 2008.
|
| Abstract:
|
The mountain yellow-legged frog complex (Rana muscosa complex) has disappeared from most of its historic localities in the Sierra Nevada of California, and airborne pesticides from the Central Valley have been implicated as a causal agent. To determine the distributions and concentrations of pesticides in the habitat of this species, we
sampled air, sediment, and Pacific treefrog (Pseudacris regilla) tadpoles at high elevation (2754-3378 m) throughout Sequoia and Kings Canyon National Parks. Twenty-eight sites were sampled (14 dispersed areas, 2 ponds/area) twice during summer of 2005. Passive air sampling devices, which sampled air over 30-d intervals, detected only the pesticide endosulfan II frequently. In sediment and tadpoles, we found nine pesticides or their breakdown products frequently: the currently used endosulfan (I & II), endosulfan sulfate, dacthal, and chlorpyrifos, and the historically used DDE, chlordane (trans), and
nonachlor (cis & trans). Concentrations were low, a few ng/g dry mass (ppb) or less for sediment and tadpoles. Pesticide distributions showed a general decrease in concentration with distance from agricultural areas in the Central Valley (43-82 km away), but Pearson r2 values were low. A preliminary analysis of the distribution of pesticides relative to the distribution of remaining populations.
|
|
| PRESENTATION |
US Environmental Protection Agency Future Use of Goes-R in Air Quality Assessments (Invited Talk) |
01/25/2008
|
|
|
|
SZYKMAN, J., J. Al-Saadi, A. Chu, T. PACE, R. MATHUR, G. POULIOT, B. Pierce, S. Kondragunta, A. Soja, C. Kittaka, R. Scheffe, J. Fishman, AND F. DIMMICK. US Environmental Protection Agency Future Use of Goes-R in Air Quality Assessments (Invited Talk). Presented at 5th GOES-R User Conference AMS, New Orleans, LA, January 25, 2008.
|
| Abstract:
|
There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact Field.
|
|
| PRESENTATION |
3D Air Quality and the Clean Air Interstate Rule: Lagrangian Sampling of Cmaq Model Results to Aid Regional Pollution Accountability Metrics. |
01/24/2008
|
|
|
|
Fairlie, D., J. SZYKMAN, B. R. Pierce, A. Gilliland, J. Engel-Cox, S. Weber, C. Kittaka, J. Al-Saadi, R. SCHEFFE, F. DIMMICK, AND J. TIKVART. 3D Air Quality and the Clean Air Interstate Rule: Lagrangian Sampling of Cmaq Model Results to Aid Regional Pollution Accountability Metrics. Presented at American Meteorological Society 88th Annual Meeting, New Orleans, LA, January 20 - 24, 2008.
|
| Abstract:
|
Presentation materials. If further information is requested, please refer to the bibliographic citation and contact the person listed under Principlal Investigator
|
|
| PRESENTATION |
Application of Satellite Aerosol Optical Depth and Airborne Lidar Data for Monitoring Fine Particulate Concentration in San Joaquin Valley, California |
01/24/2008
|
|
|
|
Al-Saadi, J., R. ROSEN, C. BOHNENKAMP, J. SZYKMAN, A. Chu, J. Hair, R. Ferrare, C. Hostetler, G. Arcemont, A. Kaduwela, C. Kittaka, AND J. Lewis. Application of Satellite Aerosol Optical Depth and Airborne Lidar Data for Monitoring Fine Particulate Concentration in San Joaquin Valley, California. Presented at American Meteorlogical Society 88th Annual Meeting, New Orleans, LA, January 20 - 24, 2008.
|
| Abstract:
|
Presentation materials. If further information is requested, please refer to the bibliographic citation and contact the person listed under Principal Investigator.
|
|
| PRESENTATION |
Historical Analysis of the Relationship of Streamflow Flashiness With Population Density, Imperviousness, and Percent Urban Land Cover in the Mid-Atlantic Region |
05/16/2008
|
|
|
|
JARNAGIN, S. Historical Analysis of the Relationship of Streamflow Flashiness With Population Density, Imperviousness, and Percent Urban Land Cover in the Mid-Atlantic Region. Presented at World Environmental and Water Resource Congress 2008, Honolulu, HI, May 12 - 16, 2008.
|
| Abstract:
|
Methods: This study is an examination of the relationship between stream flashiness and watershed-scale estimates of percent imperviousness, degree of urban development, and population density for 150 watersheds with long-term USGS National Water Information System (NWIS) historical daily mean streamflow datasets in EPA Region 3 (R3, Mid-Atlantic USA). I used decadal Census population data from 1930-2000, proportionally allocated into 2000-era county boundaries to estimate population density. For decades after 1960, higher spatial resolution census data were used along with the LandScan 1998 dasymetric estimation of population density at a 450 m grid cell spatial resolution. Temporal land use/land cover (LULC) data: 1973 North American Landscape Characterization (NALC) data, 1992 National Land Cover Data (NLCD1992), and NLCD2001 were used to estimate a 'percent urban developed' parameter for each watershed. The NLCD2001 Imperviousness data layer and the ArcView ATtILA extension (US EPA, 2004) was used for a 2001 estimator of watershed imperviousness and both the coefficient technique of Jennings et al. (2004) and ATtILA were used to estimate 1992 watershed imperviousness. The Richards-Baker Flashiness Index (R-B Index, Baker et al., 2004) was applied to historical NWIS streamflow to calculate annual flashiness values for the period of record for each station.
Results: Historical changes in mean stream flashiness were correlated with county-scale based changes in watershed population density estimates. Streamflow stations that showed significant changes in historical flashiness had a higher mean population density than those that showed no change. The strength of the population-flashiness correlation increased as the spatial scale of the population estimator was reduced, with dasymetric LandScan data giving the best relationship. LULC and imperviousness estimators were equally effective at exploring the relationship between stream flashiness and watershed development. Urban development classes 'None' and 'Rural' were statistically the same while increasing levels of development were associated with statistically significant increases in stream flashiness. Watersheds with less than 20% 'urban' development displayed background levels of stream flashiness and mean flashiness increase with urban development density thereafter. My results support previous research that suggests low intensity development does not substantially alter streamflow. Increasing degrees of development intensity do significantly alter streamflow. One use of this dataset is to search for 'positive outliers' - where predicted stream flashiness is less than anticipated by the level of urban development. Detailed examination of these watersheds may yield examples where BMPs or patterns of development have been successful at mitigating the impact of urban development on stream hydrology.
|
|
| PRESENTATION |
Comparing Hplc-Esi-Itms and Uplc-Esi-Oa-Tof-MS in Characterizing Macrolide Antibiotics and Illicit Drugs in Complex Environmental Matrices |
06/05/2008
|
|
|
|
JONES-LEPP, T. L. Comparing Hplc-Esi-Itms and Uplc-Esi-Oa-Tof-MS in Characterizing Macrolide Antibiotics and Illicit Drugs in Complex Environmental Matrices. Presented at American Society of Mass Spectrometry, Denver, CO, June 01 - 05, 2008.
|
| Abstract:
|
Among the challenges of characterizing emerging contaminants in complex environmental matrices (e.g., biosolids, sewage, or wastewater) are the co-eluting interferences. For example, surfactants, fats, and humic acids, can be preferentially ionized instead of the analyte(s) of interest, or mask their presence. Modern analytical detection techniques such as GC- and LC-MS/MS (i.e., ion traps, triple
quadrupoles, magnetic sector, and time-of- flight mass spectrometers) can be used to deconvolute the interferences from the compounds of interest. This presentation will discuss using a Varian 500 LC-MS iontrap (MS/MS mode) as a screening tool, with follow-up confirmation using a Waters LCT UPLC-TOF for assigning accurate masses to
the emerging contaminants.
|
|
| PRESENTATION |
Rapid, Automated Determination of Elemental Compositions of Ions in Mass Spectra Obtained With An Open-Air Ion Source |
06/05/2008
|
|
|
|
GRANGE, A. H. AND G. SOVOCOOL. Rapid, Automated Determination of Elemental Compositions of Ions in Mass Spectra Obtained With An Open-Air Ion Source. Presented at 56th ASMA Conference on Mass Spectromety and Allied Topics, Denver, CO, June 01 - 05, 2008.
|
| Abstract:
|
Introduction. An inexpensive autosampler employing a 3' long, 1/4"-square aluminum bar riding on N-scale model railroad flat cars provides mass spectra obtained with a DART/TOFMS for analytes absorbed on 76 cotton swab, wipe samples in 7.5 min. A field sample carrier built around the bar aids sample collection and provides the samples nearly ready for analysis. Elimination of sample extraction, clean-up, and chromatography steps provides rapid analyses and high throughput. Superfund sites, dispersive events, and clandestine drug labs could
be characterized, their remediation monitored in real-time, and their clean-up documented rapidly with high spatial resolution. For dispersion of chemicals in public places, rapid interpretation of composite mass spectra and identification of analytes is essential for assessing risks to the public and to remediators. Software that correlates product and precursor ions based on their exact masses and relative isotopic abundances (RIAs) was developed to address this need.
Method. An Ion Extraction Program (IEP) partially interprets mass spectra obtained at low, moderate, and high in-source CID voltages. Exact mass difference tests classify protonated molecules (precursor ions), precursor ion oxides, and ammoniated precursor, protonated dimer, and ammoniated dimer ions. An Input and Output Program
(IOP) provides an Ion Correlation Program (ICP) with a precursor ion and each possible product ion in succession to test for ion correlations, which require that the summed compositions for the product ion and its corresponding neutral loss provide a possible precursor ion composition. Upper elemental limits are determined from the
possible precursor ion compositions that remain after each ion correlation. The cycle is repeated using the most limiting upper elemental limits. Exact mass and RIA error limits for the precursor ion and product ions are varied to limit the number of precursor ion, product ion, and neutral loss compositions, while not overlooking lowabundance
product ions. Preliminary Data. The IEP uses exact mass difference tests to classify ions as monoisotopic precursor ions, +1 or +2 isotopic ions, +2, +4, +6, or +8 isotopic ions from ions containing halogen atoms, [M-H]+ or [M-2H]+ ions, adducted ions, or dimeric ions. Because dimeric ions fragment at the moderate CID voltage, precursor ions must
meet thresholds in both the low and moderate CID voltage spectra. Product ions are obtained from the high CID voltage spectrum. %1 RIAs and %2 RIAs were calculated for 20 and 14 of 21 precursor ions, respectively, for which abundance thresholds were met. The ICP establishes lower elemental limits for S and Cl and upper
elemental limits for Cl and Br from %2 RIAs. Considering both exact mass and RIAs and starting with error limits of ± 2 mDa and ± 20% of the RIA values, possible elemental compositions are found for the precursor ion. If none are found, the error limits are gradually increased until a composition(s) is possible. For product ions, error limits of 2 mDa and 20% and 4 mDa and 40% are used. After each ion correlation, the IOP updates a list of correlated ions and their possible compositions. The output is a text file that contains lists of the most abundant monoisotopic ions, precursor ions, adducted or dimeric ions, correlated ions and their compositions, and unique ion correlations when multiple precursor ions are found in composite mass spectra. Unique and correct ion compositions were found for 20 of 21 precursor ions from standards with masses between 95 and 415 Da when
the elements C, H, N, O, Cl, Br, F, P, and S were considered. The correct compositions for the precursor ions from three-component and seven-component mixtures were also found, when F and P were not included for the latter mixture. Novel Aspect. Automated variation of elemental limits and mass and RIA errors to determine ion compositions
and classification of ions related to precursor ions based on exact mass tests
|
|
| PRESENTATION |
Parabens and Sunscreens in the Environment: Determination By Hplc-Esi-MS/MS and Gc-MS and Calculation of Phototoxicity |
06/05/2008
|
|
|
|
ROSAL, C. G. AND L. D. BETOWSKI. Parabens and Sunscreens in the Environment: Determination By Hplc-Esi-MS/MS and Gc-MS and Calculation of Phototoxicity. Presented at 56th American Society of Mass Spectrometry, Denver, CO, June 01 - 05, 2008.
|
| Abstract:
|
Ultraviolet (UV)-absorbing chemicals are widely used in cosmetics, sunscreens, and plastics to block UV radiation from the sun. Parabens are preservatives and are used extensively in cosmetics, pharmaceuticals, and foods to prevent microbial growth and preserve a product’s integrity over time. Studies show that some sunscreens and parabens demonstrate estrogenicity and multiple hormonal activities in vitro. Because of the high consumption volume and high lipophilicity of sunscreens, these compounds have the potential to enter and persist in the environment and bioaccumulate in tissues of living organisms. This research aims to monitor and evaluate potential sources of exposure of these compounds in different environmental compartments. This poster presents method development and preliminary data.
Method:
An HPLC-ESI-MS/MS and a complementary GC-MS method were developed to determine the presence of select parabens and sunscreens in environmental samples. Development of an extraction method of these compounds from sewage biosolids is underway. Additionally, excited-state calculations were performed on these compounds to determine possible phototoxicity to evaluate those compounds that may present health risks.
Preliminary Data:
The HPLC method developed was able to separate most of the target compounds. Analysis was performed in both positive and negative modes and using MS/MS experiments in a single run using gradient elution. The selected reaction monitoring (SRM) ion (most abundant fragment ion) for each compound was produced by reducing the precursor ion to about 15% abundance relative to the most abundant ion. The GC-MS method complements the LC-MS especially for lipophilic compounds.
Excited state calculations were performed on 24 of these compounds. From previous work on polycyclic aromatic hydrocarbons, a correlation was made between excited-state energies and phototoxicity. Triplet excited-state energies between 2.0 and 2.5 eV showed phototoxicity based on experimental tests. None of the 24 compounds in this study was in this range. Only three of the compounds were under 3.0 eV. These three compounds, however, have demonstrated estrogenicity in vitro in some research, which indicates that the range from 2.5 to 3.0 eV should be watched for potential ill effects.
Novel Aspect:
Multifaceted approach for sunscreen products: theoretical methods to predict phototoxicity, LC-MS for polar compounds, and GC-MS for lipophilic compounds.
|
|
| PRESENTATION |
Pharmaceuticals as Environmental Pollutants: Issues Regarding Analysis |
05/05/2008
|
|
|
|
JONES-LEPP, T. L. Pharmaceuticals as Environmental Pollutants: Issues Regarding Analysis. Presented at American Society of Mass Spectrometry, Denver, CO, June 01 - 05, 2008.
|
| Abstract:
|
The Clean Water Act (CWA) provides the legislative mandate for the United States Environmental Protection Agency’s Water Quality Program to restore and maintain the chemical, physical, and biological integrity of the nation’s waters. Therefore, a common goal is to maintain water quality integrity and to protect aquatic systems from pollution and degradation of habitat. Over the last several years scientists
worldwide have newly identified some traditional chemicals as having biological effects. All chemicals can potentially enter the environment at some point in their lifecycle, and many will undergo structural transformation. This presentation focuses on one subset
comprising pharmaceuticals, steroids, and hormones. One of the basic questions being asked with regard to environmental exposure to pharmaceuticals is, what analytical research tools (e.g., mass spectrometric techniques) and methods are necessary to identify
trace levels of pharmaceuticals in a variety of environmental matrices--from source waters to drinking water, from sewage biosolids to fish tissue. Because of the many ways in which pharmaceuticals can enter the environment, and their diverse chemical functionalities, we cannot rely on traditional analytical techniques (e.g., LC/UV, or GC/MS) to track the source of environmental exposure. Many new analytical tools are
being investigated by scientists worldwide. For example, solid-phase extraction coupled with LC/MS/MS or UPLC-oa-TOF for pharmaceuticals, and GC/MS/MS for steroids and hormones. Other advanced mass spectrometric techniques using high resolution mass spectrometry and accurate mass software have been used for identifying unknowns.
|
|
| PRESENTATION |
Pharmaceuticals and Personal Care Products (Ppcps) as Environmental Pollutants: An Overview of the Science |
02/07/2008
|
|
|
|
DAUGHTON, C. G. Pharmaceuticals and Personal Care Products (Ppcps) as Environmental Pollutants: An Overview of the Science. Presented at Genetic Biomarkers as Indicators for Pollution in Fish, Cairo, EGYPT, February 05 - 07, 2008.
|
| Abstract:
|
Presentation materials. If further information is requested, please refer to the bibliographic citation and contact the person listed under Principal Investigator.
|
|
| PRESENTATION |
Geometry Within Geographic Science (Spatial Analysis: GIS and Remote Sensing) |
02/13/2008
|
|
|
|
IIAMES, J. S. Geometry Within Geographic Science (Spatial Analysis: GIS and Remote Sensing). Presented at Broughton High School, Research Triangle Park, NC, February 13, 2008.
|
| Abstract:
|
Presentation materials. If further information is requested, please refer to the bibliographic citation and contact the person listed under Principal Investigator.
|
|
| PRESENTATION |
Evaluating Hydrological Response to Forecasted Land-Use Change: Scenario Testing With the Automated Geospatial Watershed Assessment Tool |
05/22/2008
|
|
|
|
KEPNER, W. G., D. J. SEMMENS, M. Hernandez, AND D. Goodrich. Evaluating Hydrological Response to Forecasted Land-Use Change: Scenario Testing With the Automated Geospatial Watershed Assessment Tool. Presented at 2008 Science Forum, Washington, DC, May 20 - 22, 2008.
|
| Abstract:
|
Studies of future management and policy options based on different
assumptions provide a mechanism to examine possible outcomes and especially their likely benefits or consequences. Planning and assessment in land and water resource management are evolving toward complex, spatially explicit regional assessments. These
problems have to be addressed with distributed models that can compute runoff and erosion at different spatial and temporal scales. The extensive data requirements and the difficult task of building input parameter files, however, have long been an obstacle to the timely and cost-effective use of such complex models by resource managers. The U.S. EPA Landscape Ecology Branch in collaboration with the USDA-ARS Southwest Watershed Research Center has developed a geographic information system (GIS) tool to facilitate this process. A GIS provides the framework within which spatially distributed data are collected and used to prepare model input files, and model results are evaluated. The Automated Geospatial Watershed Assessment (AGWA) tool uses widely available standardized spatial datasets that can be obtained via the internet at no cost to the user. The data are used to develop input parameter files for KINEROS2 and SWAT, two
watershed runoff and erosion simulation models that operate at different spatial and temporal scales. AGWA automates the process of transforming digital data into simulation model results and provides a visualization tool to help the user interpret results. Results from multiple simulations can be compared for the purpose of detecting hydrologic response to landscape or climate change. Land-use planning is facilitated by the comparison of results from simulations based on forecasted future scenarios. The utility of AGWA in joint hydrologic and ecological investigations is demonstrated for two diverse case studies in northwest Oregon (Willamette River basin) and southeastern
Arizona (San Pedro River). There are currently two versions of AGWA available: AGWA 1.5 for users with Environmental Systems Research Institute (ESRI) ArcView 3.x GIS software and AGWA 2.0 for users with ESRI ArcGIS 9.x.
|
|
| PRESENTATION |
Modeling Long-Term Dynamics of Litter Accumulation in Response to Static and Variable Hydroperiods |
07/25/2008
|
|
|
|
CHRISTENSEN, J., W. Crumpton, AND A. van der Valk. Modeling Long-Term Dynamics of Litter Accumulation in Response to Static and Variable Hydroperiods. Presented at 8th INTECOL International Wetlands Conference, Cuiaba, BRAZIL, July 20 - 25, 2008.
|
| Abstract:
|
Accumulated litter from emergent species like the cattail hybrid (Typha glauca Godr.) can influence local abiotic conditions, other biota, and ecosystem processes. Litter accumulation results from high production coupled with slow breakdown rates. Wetland managers regularly
manipulate wetland hydrology via drawdowns to increase production and extent of emergent species but it is unclear how these drawdowns influence litter dynamics. A model was developed to investigate the long-term dynamics of litter in response to multiple scenarios involving spatial extent, production, and water level manipulations. This model is the first attempt to investigate long-term litter dynamics in hydrologically variable wetlands and is needed to understand the impact of hydrological events on litter, local conditions, and biogeochemical processes. The Marsh Ecology Research Program (MERP) at Delta Marsh, Canada monitored emergent biomass and litter mass following an experimental high water and drawdown event that reset the plant community and litter levels. This model uses data and breakdown and distribution models derived from the MERP study to investigate long-term
litter dynamics. Under stable distributions, stable annual biomass (500 g/m2), and stable water levels, the litter levels off after 3-4 yrs at ~200 g/m2 at a water depth of 1-20 cm where the majority of Typha is located. These litter values are comparable with observed litter mass values taken in Delta Marsh after 20 years of stable conditions. Under increasing distribution and increasing biomass but stable water levels, such as what occurred in MERP following the high water- drawdown event, the litter levels stabilize after 12 years once extent and production stabilize. This represents a substantial lag time for the recovery of wetlands that experience extreme events and has implications for wetland restoration and creation projects. Drawdowns decrease the litter mass considerably during the year of drawdown due to higher
breakdown rates. With drawdowns every 5 or 10 years, litter levels return to pre-drawdown levels after 2-3 yrs if production and extent remain unchanged. Drawdowns every other year keep litter very low and do not allow for litter levels to stabilize. The model indicates that drawdowns can heavily influence litter accumulation of Typha spp. with significant
consequences for local conditions, nutrient budgets, and biogeochemical processes within the marsh.
|
|
| PRESENTATION |
Decision Support Tool for Evaluating Vulnerability to Hazardous Air Pollutants in the Southeast |
05/22/2008
|
|
|
|
MEHAFFEY, M. H., R. TANKERSLEY, L. MILLER, AND E. R. SMITH. Decision Support Tool for Evaluating Vulnerability to Hazardous Air Pollutants in the Southeast. Presented at 2008 Science Forum, Washington, DC, May 20 - 22, 2008.
|
| Abstract:
|
Valued ecological endpoints such as threatened and endangered species and critical habitat are often evaluated for proximate impacts such as nearby development and direct impacts such as logging. Exposure to atmospheric pollutants can exacerbate the affects
on these already vulnerable species and ecosystems. While EPA Region 4 only comprises one tenth of the United States land area, it is home to over 20% of the nation’s population and is responsible for over one third of the toxics chemicals released to the air from mid- to large size industry. Yet the southeast harbors significant populations of
threatened and endangered species, valued ecological resources such as timber, and a large portion of habitat for a variety of species. This juxtaposition of important and diverse ecosystems and large quantity of toxic releases is what makes the southeast a prime location for exposure analysis. The study utilizes a new integration technique for
spatially mapping relative toxicity to species groups across the southeastern states and presents the data via the Regional Vulnerability Environmental Decision Toolkit (ReVAEDT).
|
|
| PRESENTATION |
Partial Least Squares (Pls) Regression for Small Sample With Collinear Predictors in Landscape Ecology |
04/24/2008
|
|
|
|
NASH, M. S. AND R. D. LOPEZ. Partial Least Squares (Pls) Regression for Small Sample With Collinear Predictors in Landscape Ecology. Presented at 25th Annual Coonference on Managing Environmental Quality System, Austin, TX, April 24 - 27, 2006.
|
| Abstract:
|
The primary objective of the U.S. Environmental Protection Agency's (EPA) Landscape Ecology research program is investigation of associations between surface water constituents and landscape metrics.
|
|
| PUBLISHED REPORT |
Interim Guidance for Developing Global Positioning System Data Collection Standard Operating Procedures and Quality Assurance Project Plans |
02/26/2008
|
|
|
|
KOHL, N. W., G. BRILIS, C. MIDDLETON, R. Strohman, N. G. TALLENT-HALSELL, T. Smith, L. M. PETTERSON, J. C. WORTHINGTON, AND A. LOWE. Interim Guidance for Developing Global Positioning System Data Collection Standard Operating Procedures and Quality Assurance Project Plans. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-08/020, 2008.
|
| Abstract:
|
The United States Environmental Protection Agency Geospatial Quality Council developed this document to harmonize the process of collecting, editing, and exporting spatial data of known quality using the Global Positioning System (GPS). Each organizational entity may adopt this document as the core of their Standard Operation Procedures (SOP) manual on GPS data collection procedures.
|
|
| PUBLISHED REPORT |
Report on the Geoelectrical Detection of Surfactant Enhanced Aquifer Remediation of Pce: Property Changes in Aqueous Solutions Due to Surfactant Treatment of Perchloroethylene: Implications to Geophysical Measurements |
03/31/2008
|
|
|
|
WERKEMA, D. D. Report on the Geoelectrical Detection of Surfactant Enhanced Aquifer Remediation of Pce: Property Changes in Aqueous Solutions Due to Surfactant Treatment of Perchloroethylene: Implications to Geophysical Measurements. U.S. Environmental Protection Agency, Washington, D.C., EPA/600/R-08/031, 2008.
|
| Abstract:
|
Select physicochemical properties of nine surfactants which are conventionally used in the remediation of perchloroethylene (PCE, a.k.a. tetrachloroethene) were evaluated with varying concentrations of PCE and indicator dyes in aqueous solutions using a response
surface quadratic design model of experiment. Stat-Ease Design Expert v7 was used to generate the experimental design and perform the analysis. Two hundred forty experiments were performed using PCE as a numerical factor (coded A) from 0 to 200 parts per million (ppm), dye type (coded B) as a 3-level categorical nominal factor, and surfactant type (coded C) as a 10-level categorical nominal factor. Five responses were measured: temperature (oC), pH, conductivity (μS/cm), dissolved oxygen (DO, mg/L), and density (g/mL). Diagnostics proved a normally distributed predictable response for all of the measured responses except pH. The result from the Box-Cox plot for transforms recommended a power transform for the conductivity response with lambda (λ) = 0.50, and for the DO response with, λ = 2.2. The overall mean of the temperature response proved to be a better predictor than the linear model. The conductivity response is best fitted with a linear model using significant coded factors B and C. The DO model
is also linear with coded factors A, B, and C significant. The model for the density response is a two factor interaction (2FI) model with significant coded factors C and AC. Some of the surfactant treatments of PCE significantly alter the conductivity, DO, and density of the aqueous solution. However, the magnitude of the density response is so
small that it does not exceed the instrument tolerance. Results for the conductivity and DO responses provide predictive models for the surfactant treatment of PCE and may be useful in determining the potential for geophysically monitoring surfactant enhanced
aquifer remediation (SEAR) of PCE. As the aqueous physical properties change due to surfactant remediation efforts, so will the properties of the subsurface pore water, all of which are influential factors in geophysical measurements. Geoelectrical methods are potentially the best suited to measure SEAR alterations in the subsurface because the conductivity of the pore fluid has the largest relative change. This research has provided
predictive models for alterations in the physicochemical properties of the pore fluid to SEAR of PCE. Future investigations should address the contribution of the solid matrix in the subsurface and the solid-fluid interaction during SEAR of PCE contamination.
|
|
| PUBLISHED REPORT |
Scout 2008 (Windows Version 1.00.00) Software Package, Including Scout 2008 (Version 1.00.00) User Guide |
03/31/2008
|
|
|
|
Singh, A., R. Maichle, N. Armbya, A. Singh, AND J. M. NOCERINO. Scout 2008 (Windows Version 1.00.00) Software Package, Including Scout 2008 (Version 1.00.00) User Guide. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-08/038, 2008.
|
| Abstract:
|
The Scout 2008 version 1.0 software package provides a wide variety of classical and robust statistical methods that are not typically available in other commercial software packages. A major part of Scout deals with classical, robust, and resistant univariate and multivariate outlier identification, and robust estimation methods that have been available
in the statistical literature over the last three decades. Outliers in a data set represent those observations which do not follow the pattern displayed by the majority (bulk) of the data. It should be pointed out that all of the outlier identification methods are meant to identify outliers in a data set typically representing a single population. Outlier identification methods are not meant to be used on clustered data sets representing
mixture data sets, especially when more than two clusters may be present in the data set. On data sets having several clusters, other methods such as cluster analysis and principal component analysis may be used. Several robust estimation and outlier identification methods that have been incorporated into Scout 2008 include: the iterative classical method, the iterative influence function (e.g., Biweight, Huber, PROP)-based M-estimates method, the multivariate trimming
(MVT) method, the least median-of-squared residuals (LMS) regression method, and the minimum covariance determinant (MCD) method. Some initial choices for the iterative estimation of location and scale are also included in Scout 2008, including the orthogonalized Kettenring and Gnanadesikan (OKG) method; the median, median absolute deviation (MAD), or interquartile range (IQR)-based methods; and the MCD
method. Scout offers classical and robust methods to estimate: the multivariate location and scale, univariate robust intervals, multiple linear regression parameters, principal components (PCs), and discriminant (Fisher, linear, and quadratic) functions (DFs). The
discriminant analysis module of Scout can perform cross validation using several methods, including leave-one-out (LOO), split samples, M-fold validation, and bootstrap methods. Below detection limit observations or nondetect (ND) data are inevitable in many environmental and chemometrics applications. Scout has several univariate graphical and inferential methods that can be used on uncensored full data sets and also on leftcensored data sets with below detection limit (DL) observations. Specifically, Scout can be used to: compute various interval estimates, perform typical univariate goodness-of-fit (GOF) tests, and perform single and two-sample hypothesis tests on uncensored data sets and left-censored data sets with nondetect observations. Classical univariate statistical inference methods (e.g., intervals and hypothesis testing) in Scout 2008 can also handle data sets with below detection limit observations. In Scout 2008, emphasis is given to graphical displays of multivariate data sets. Both two-dimensional and three-dimensional graphs can be generated using Scout. The classical and robust methods listed above are supplemented with formal multivariate classical and robust graphical displays, including the quantile-quantile (Q-Q) plots of the Mahalanobis distances (MDs), index plots of the MDs, distance-distance (D-D) plots,
scatter plots of raw data, PC scores, and DF scores with prediction or tolerance ellipsoids superimposed on the respective scatter plots. Those graphical displays can be drawn using the critical values of the MDs obtained using the exact scaled beta distribution of the MDs or an approximate chi-square distribution of the MDs. Some graphical classical and robust methods comparison tools are also available in Scout so that one can graphically compare the performances of those methods. Scout can be used to display tolerance ellipsoids or prediction ellipsoids for the various outlier identification methods on the same graph and to display robust regression lines for the various regression
methods on the same graph. Scout 2008 also offers some GOF test statistics to assess multivariate normality. Several GOF test statistics, including the multivariate kurtosis, the skewness, and the correlation
coefficient between the ordered MDs and the scaled beta (or chi-square) distribution quantiles, are displayed on a Q-Q plot of the MDs. The associated critical values of those GOF test statistics (obtained via extensive simulation experiments) are also displayed on the graphical displays of the Q-Q plots of the MDs. Two standalone software packages, ProUCL 4.00.02 and ParallAX, have also been incorporated into Scout 2008. ProUCL 4.00.02 is a statistical software package
developed to address environmental applications, whereas the ParallAX software offers graphical and classification tools to analyze multivariate data using the parallel coordinates.
|
|
| PUBLISHED REPORT |
Localizing the Rangeland Health Method for Southeastern Arizona |
05/15/2008
|
|
|
|
Buono, J., P. Heilman, E. Carrillo, D. Robinett, AND M. S. NASH. Localizing the Rangeland Health Method for Southeastern Arizona. U.S. Environmental Protection Agency, Washington, DC, 2008.
|
| Abstract:
|
The interagency manual Interpreting Indicators of Rangeland Health, Version 4 (Technical Reference 1734-6) provides a method for making rangeland health assessments. The manual recommends that the rangeland health assessment approach be adapted to local conditions. This technical note describes the field methods and results of localizing the rangeland health method to two ecological sites in southeastern Arizona: Loamy Upland and Sandyloam Upland, both in Major Land Resource Area 41-3, Southeastern Arizona Basin and Range, Semidesert Grassland. The products of the effort are reference sheets that describe the condition of areas with little or no departure from reference conditions (the historic climax plant community) as well as
evaluation matrices that describe five departure categories for each of the 17 indicators. For a number of indicators the departures in the evaluation matrix were found to be nonlinearly related to the departure categories. Expanding this effort to document reference sheets and evaluation matrices for other ecological sites would require substantial effort, but would facilitate consistent interagency application of the Rangeland Health method.
|
|
| PUBLISHED REPORT |
Analytical Protocol (Gc/Ecnims) for Oswer's Response to Oig Report (2005-P-00022) on Toxaphene Analysis |
05/19/2008
|
|
|
|
BRUMLEY, W. C. Analytical Protocol (Gc/Ecnims) for Oswer's Response to Oig Report (2005-P-00022) on Toxaphene Analysis. 2008.
|
| Abstract:
|
The research approached the large number and complexity of the analytes as four separate groups: technical toxaphene, toxaphene congeners (eight in number), chlordane, and organochlorine pesticides. This approach was advantageous because it eliminated potential interferences among the many analytes with each other and made the analysis simpler for users. Only DDD, DDE, and DDT were found to be insensitive to NIMS. The protocol was tested on spiked soil and then subjected to a clean matrix precision test with an intra-laboratory study by three independent analyses. The approach also allows the analytes of a given group to be determined in a single monitoring window, greatly simplifying the methodology and eliminating the need to define retention windows for the monitoring of a limited number of analytes. The complex issue of separations of all congeners of toxaphene and choice of specific cleanups was left to guidance in Method 8081a and other sections of SW-846. Thus, GC/NIMS can act in a complementary fashion to GC/ECD that is already being practiced in the Region or completely replace it at the discretion of the analyst.
|
|
| PUBLISHED REPORT |
Guidelines to Assessing Regional Vulnerabilities |
07/31/2008
|
|
|
|
SMITH, E. R., M. H. MEHAFFEY, R. O'Neil, T. G. WADE, J. V. KILARU, AND L. Tran. Guidelines to Assessing Regional Vulnerabilities. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-08/078 (NTIS PB2009-100858), 2008.
|
| Abstract:
|
Decision-makers today face increasingly complex environmental problems that require integrative and innovative approaches for analyzing, modeling, and interpreting various types of information. ReVA acknowledges this need and is designed to evaluate methods and models for synthesizing diverse kinds of available information on the distribution of stressors and sensitive ecological resources. As with any study, the first and probably most important step is to establish a clear goal. For ReVA, the goal is to develop and demonstrate approaches that use existing data to evaluate current and future conditions and vulnerabilities of valued resources (native biodiversity, water quality, forest productivity, etc.) resulting from ecological drivers of change and later, management alternatives.
|
|
| SITE DOCUMENT |
Performance of the Cape Technologies Df1 Dioxin/Furan Immunoassay Kit for Soil and Sediment Samples |
02/29/2008
|
|
|
|
BILLETS, S. AND J. L. GOETZ. Performance of the Cape Technologies Df1 Dioxin/Furan Immunoassay Kit for Soil and Sediment Samples. U.S. Environmental Protection Agency, Washington, DC, EPA/540/R-08/002, 2008.
|
| Abstract:
|
A demonstration of screening technologies for determining the presence of dioxin and dioxin-like compounds in soil and sediment was conducted under the U.S. Environmental Protection Agency’s (EPA’s) Superfund Innovative Technology Evaluation Program in Saginaw, Michigan in 2004. The objectives of the demonstration included evaluating each participating technology’s accuracy, precision, sensitivity, sample throughput, tendency for matrix effects, and cost. The test also included an assessment of how well the technology’s results compared to those generated by established laboratory methods using high-resolution mass spectrometry (HRMS). The demonstration objectives were accomplished by evaluating the results generated by each technology from 209 soil, sediment, and extract samples. The test samples included performance evaluation (PE) samples (i.e., contaminant concentrations were certified or the samples were spiked with known contaminants) and environmental samples collected from 10 different sampling locations. The PE and environmental samples were distributed to the technology developers in blind, random order. One of the participants in the original SITE demonstration was CAPE Technologies, which demonstrated the use of the DF1 Dioxin/Furan Immunoassay Kit.
The developers and potential users of the technologies provided feedback after the demonstration. There was significant interest in evaluating the performance of these technologies on a site-specific basis. This would more closely represent the expected application of the technologies than was the case during the original demonstration, which targeted technology performance when challenged with a broad range of sample types. Consequently, a second test (referred to as the “site-specific study”) was conducted in which the developers were given a total of 112 samples that were segregated by site of origin. In contrast to the original demonstration, in which all sample information was unknown, environmental information for each site was provided to the developers to more closely represent the background information that would be available to contractors supporting a site-specific application. Each batch included some samples previously analyzed as part of the SITE Dioxin Demonstration and some unique samples in archive that were not used as part of the SITE Dioxin Demonstration, along with replicates and quality control (QC) samples. Only dioxin and furan concentrations were evaluated in this study. The developers were given the HRMS data from the SITE Dioxin Demonstration so that they would have the opportunity to utilize a site-specific calibration and knowledge regarding typical congener patterns at a particular site. Data analysis focused on analytical performance on a site-specific basis, and included an evaluation of comparability to the HRMS total dioxin/furan toxicity equivalents (TEQD/F) results over a range of TEQ concentrations from 10 to 12,000 picogram/gram, precision on replicate analyses, and QC sample results.
This report describes the experimental design of the site-specific study, the analytical methods used, and comparisons of the TEQD/F results from the HRMS data to those reported by CAPE Technologies. The data generated and evaluated during the site-specific study showed that the TEQ data produced by the DF1 was more comparable to the HRMS TEQD/F data than was the data reported during the original SITE demonstration. The quantitative correlation with HRMS TEQD/F was 0.94 for all the samples in the site specific study. The average percent recovery value was 122% with a range between 48% and 354%. The average relative standard deviation for the site specific study was 26%, with a range between 6% and 63%. These results show that the DF1 kit could be used as an effective screening tool to determine areas of greatest concern for cleanup at a site and could help to minimize the number of more expensive analyses needed for specific analytes, particularly considering that the cost and the time to analyze samples is significantly less than that of HRMS analyses.
|
|
|
|
