Waste Sites (waste + site)

Distribution by Scientific Domains

Kinds of Waste Sites

  • hazardous waste site


  • Selected Abstracts


    Analytical, Risk Assessment, and Remedial Implications Due to the Co-Presence of Polychlorinated Biphenyls and Terphenyls at Inactive Hazardous Waste Sites

    REMEDIATION, Issue 1 2000
    James J. Pagano
    Investigations conducted at three inactive hazardous waste sites in New York State have confirmed the co-presence of polychlorinated hiphenyls (PCBs) and polychlorinated terphenyls (PCTs) in soils, sediments, and biota. The PCTs at all three sites were positively identified as Aroclor 5432, with the most probable source being the hydraulic fluid Pydraul 312A utilized for high-temperature applications. The identification of the lower-chlorinated PCT formulations in environmental samples is problematical, since PCT Aroclors 5432 and 5442 are not chromatographically distinct from the higher-chlorinated (PCB) Aroclors 1254, 1260, 1262, and 1268 using conventional gas chromatography,electron capture detection. Results from this study indicate that U.S. Environmental Protection Agency (USEPA) approved PCB methods routinely utilized by most commercial laboratories based on Florisil adsorption column chromatography cleanup are inadequate to produce valid chromatographic separation and quantitative results with soils, sediment, and biota samples containing both PCBs and PCTs. The presence of co-eluting PCBs and PCTs precludes accurate quantitation due to significant differences in PCB/PCT electron capture detector response factors, and the potential for misidentification of PCT Aroclors as higher chlorinated PCB Aroclors. A method based on alumina column adsorption chromatography was used, allowing for the accurate identification and quantitation of PCB and PCT Aroclors. The results of this study suggest that the utilization of alumina adsorption column separation may have applicability and regulatory significance to other industrially contaminated sites which historically used Pydraul 312A. Inferences. [source]


    Preferential flow and aging of NAPL in the unsaturated soil zone of a hazardous waste site: implications for contaminant transport

    JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 1 2003
    Kai U. Totsche
    Abstract Flow of non-aqueous phase liquids (NAPL) in the unsaturated zone is thought to be driven by gravity with a dominant vertical flow direction, and lateral spreading to be limited to the gradient of the relative permeabilities. The effect of soil profile build-up, preferential flow, aging, and groundwater level fluctuations is mostly neglected. The objective of our study was to check the effects of such processes on the fate of NAPL in the unsaturated soil zone. At a hazardous waste site, we conducted a field survey of the unsaturated soil zone and monitored the groundwater for a two year period. We conducted spatially resolved and depth dependent soil sampling and analysis and the evaluation of former ram and core drilling protocols. The samples were analyzed for the 16 EPA PAH and alkanes with GC-MS and GC-FID. 13C-NMR spectroscopy was used to assess structural changes of the NAPL phase. Flow of bulk NAPL along macropores and along preferential permeability structures, like sedimentation discontinuities, are the dominant transport pathways which cause large lateral spreading beyond those expected by the relative permeability gradient. Accumulation of NAPL was found at locations with abrupt textural changes and within the zone of capillary rise. Aging of NAPL results in the depletion in soluble and volatile compounds but also in oxidation and polymerization. It increases the chemical diversity and decreases the mobility of the NAPL. Thus, NAPL flow ceases much earlier than expected from the capillary forces. As chemical transformation is restricted to the NAPL water/air interface, a skin-like thin film is formed which encapsulates and preserves the bulk NAPL from further hardening, limiting contaminant mass transfer from the NAPL to the aqueous phase. Präferenzieller Fluss und Alterung nichtwässriger flüssiger Phasen (NAPL) in der ungesättigten Bodenzone eines Altlastenstandortes: Bedeutung für den Stofftransport Bei der Abschätzung der Tiefenverlagerung von nichtwässrigen Phasen (NAPL) in der ungesättigten Bodenzone ging man bisher davon aus, dass der Fluss im Boden eine dominante vertikale Fließkomponente besitzt. Die Bedeutung bevorzugter Fließwege, des Bodenprofils und der Alterung für die Ausbreitung der NAPL wurde bisher nicht untersucht. Ziel unserer Arbeiten war es daher, die Gültigkeit der Vorstellungen zum Transport von NAPL in der ungesättigten Bodenzone zu überprüfen. Hierzu wurde die ungesättigte Bodenzone an einem ehemaligen Teerwerkstandort untersucht und ein zweijähriges Grundwassermonitoring durchgeführt. Es wurde eine tiefendifferenzierte und räumlich aufgelöste Probenahme mit Rammkernsondierungen und Linern durchgeführt, sowie Bohrprotokolle vorhandener Gutachten ausgewertet. In den Proben wurden Alkane mittels GC-FID und PAK mittels GC-MS bestimmt. NAPL wurden 13C-NMR-spektroskopisch untersucht. Der Fluss von NAPL entlang präferenzieller Fließpfade ist der dominante Prozess der Tiefenverlagerung. Dabei kommt es zu einer starken lateralen Ausbreitung von NAPL weit über den Bereich hinaus, der aufgrund der heterogenen Verteilung der relativen Permeabilitäten erwartet werden würde. Innerhalb des Bodenprofils reichern sich NAPL oberhalb der Grenzflächen mit abruptem Texturwechsel und innerhalb der kapillaren Aufstiegszone an. Alterung der NAPL führt zu einer Zunahme der chemischen Diversität und zu einer Abnahme der Mobilität. Die Tiefenverlagerung von NAPL kommt viel früher zum Erliegen als durch Viskosität und Kapillarkräfte zu erwarten wäre. Die strukturchemischen Veränderungen beschränken sich jedoch auf die Grenzfläche NAPL/Wasser bzw. NAPL/Bodenluft: Es bildet sich eine dünne, verhärtete Grenzschicht aus, die die NAPL umhüllt, die weitere Alterung verlangsamt und den Stoffaustausch zwischen NAPL und Bodenwasser bzw. der Bodenluft verringert. [source]


    Oxidative mutagenicity of polar fractions from polycyclic aromatic hydrocarbon,contaminated soils

    ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 11 2008
    Joanna Park
    Abstract Soils at hazardous waste sites contain complex mixtures of chemicals and often are difficult to characterize in terms of risk to human and ecological health. Over time, biogeochemical processes can decrease the apparent concentrations of pollutants but also can lead to accumulation of new products for which toxicity and behavior in the environment are largely unknown. A bioassay-directed fractionation technique was used to assess the contribution of redox-active bacterial metabolites to the toxicity of soil contaminated with polycyclic aromatic hydrocarbons (PAHs). A reverse mutation assay with Escherichia coli WP2 uvrA/pKM101 (IC188) and E. coli WP2 uvrA oxyR/pKM101 (IC203) was used to screen fractions for genotoxicity. Strain IC203 carries the ,oxyR30 mutation, which prevents the expression of antioxidant proteins in response to oxidative stress and increases its reversion by compounds that generate reactive oxygen species (ROS). Polar fractions of PAH-contaminated soil extracts were mutagenic to strain IC203 but not to strain IC188, suggesting the involvement of ROS in genotoxicity. Genotoxic potencies ranged from 300 to 1,700 revertants per milligram of fraction. Catalase was able to decrease IC203 reversion, implicating the involvement of hydrogen peroxide as a key ROS. Oxidized PAH compounds, including quinones, were identified in the mutagenic fractions but were not by themselves mutagenic. Deasphalted whole extracts and recombined fractions were not mutagenic, indicating that interactions between compounds in different fractions can mitigate genotoxicity. [source]


    Verbreitung und Differenzierung der mitteleuropäischen Unterarten von Buglossoides arvensis (L.) I. M. Johnst. (Boraginaceae),

    FEDDES REPERTORIUM, Issue 1-2 2003
    A. Clermont
    In Mitteleuropa sind zwei Unterarten des Ackersteinsamens (Buglossoidesarvensis subsp. arvensis, B. arvensis subsp. sibthorpiana) verbreitet. Die molekularbiologische Untersuchung der nucleären ITS1-Region von 55 mitteleuropäischen Belegen verdeutlicht die Eigenständigkeit der beiden Sippen. Innerhalb des 238 Basenpaare langen Markers unterscheiden sich die Unterarten durch 15 Substitutionen (6,4 %). Die Ergebnisse lassen den Schluss zu, dass die Unterarten bisher aufgrund ihrer morphologischen Plastizität oft verwechselt und Häufigkeit und Verbreitung der Subspecies sibthorpiana unterschätzt wurden. Morphologisch lassen sich die beiden Unterarten anhand folgender Merkmale unterscheiden: Buglossoides arvensis subsp. arvensis besitzt längliche Keimblätter, eine gerade Gynobasis, einen unverdickten, geraden Pedicellus sowie cremefarbene oder selten leicht rosa gefärbte Blüten. Buglossoides arvensis subsp. sibthorpiana zeichnet sich durch runde Keimblätter, eine zur Fruchtzeit leicht zur Blütenstandsachse geneigte Gynobasis, einen schiefen, verdickten Pedicellus an den unteren Früchten und blaue, rosa oder cremefarben gefärbte Blüten aus. Weiterhin unterscheiden sich die Unterarten in ihren ökologischen Ansprüchen: B. arvensis subsp. arvensis kommt nur als Ackerunkraut vor, B. arvensis subsp. sibthorpiana wächst sowohl auf Ackerstandorten als auch auf Trockenrasen, sandigen Ruderalflächen oder in trockenen, lichten Wäldern. Distribution and differentiation of the Central European subspecies of Buglossoides arvensis (L.) I.M.Johnst. (Boraginaceae) The Corn Gromwell (Buglossoides arvensis) has two Central European subspecies, B. arvensis subsp. arvensis and B. arvensis subsp. sibthorpiana. The ITS1-region of 55 European samples was amplified and sequenced and it yielded a 238 bp fragment, which consistently differed by 15 substitutions between the two subspecies. The results suggest that the two subspecies indeed represent two independent taxa and have been confused mainly because of their morphological plasticity. Because of this confusion, distribution and abundance were poorly understood. The subspecies as here re-defined can be distinguished as follows: B. arvensis subsp. arvensis has oblong cotyledons, a horizontal gynobase, an unthickened pedicel in fruit, and a cream-coloured corolla. B. arvensis subsp. sibthorpiana has circular cotyledons, an oblique gynobase, an obliquely thickened pedicel in fruit, and a light blue to (more rarely) cream-coloured corolla. The two taxa show some degree of ecological differentiation: B. arvensis subsp. arvensis is only found as a weed in winter cereals, whereas B. arvensis subsp. sibthorpiana is occasionally found as a weed in fields, but also on dry grasslands, sandy waste sites and road sides, and in dry, open forests. [source]


    A Probabilistic Method for Estimating Monitoring Point Density for Containment System Leak Detection

    GROUND WATER, Issue 4 2000
    Randall R. Ross
    The use of physical and hydraulic containment systems for the isolation of contaminated ground water and aquifer materials associated with hazardous waste sites has increased during the last decade. The existing methodologies for monitoring and evaluating leakage from hazardous waste containment systems rely primarily on limited hydraulic head data. The number of hydraulic head monitoring points available at most sites employing physical containment systems may be insufficient to identify significant leaks from the systems. A probabilistic approach for evaluating the performance of containment systems, based on estimations of apparent leakage rates, is used to introduce a methodology for determining the minimum number of monitoring points necessary to identify the hydraulic signature of leakage from a containment system. The probabilistic method is based on the principles of geometric probability. The method is demonstrated using three-dimensional ground water flow modeling results of leakage through a vertical barrier. The results indicate that the monitoring point spacing used at many hazardous waste sites likely is inadequate to detect the hydraulic signatures of all but the largest leaks. [source]


    OPTIMAL DISCOUNTING IN CONTROL PROBLEMS THAT SPAN MULTIPLE GENERATIONS

    NATURAL RESOURCE MODELING, Issue 3 2005
    FRANK CALIENDO
    ABSTRACT. The principal contribution of this paper is the linking together of separate control problems across multiple generations using the bequest motive, intergenerational altruism, rational expectations, and solution boundary conditions. We demonstrate that discounting at the market rate of interest is an endogenous characteristic of a general equilibrium, optimal control problem that spans multiple generations. Within the confines of our model, we prove that it is optimal to discount at the market rate of interest the social benefits to distant generations from immediate clean up at toxic waste sites if the current generation that bears the cleanup cost is perfectly altruistic towards future generations. Also, we show that this result holds for alternative assumptions regarding pure time preference. Moreover, the result holds regardless of whether selfish interim generations attempt to undo the provisions made for distant generations. In our distortion-free deterministic model, the evidence for intergenerational discounting at the market rate of interest is compelling. [source]


    Down syndrome in births near landfill sites

    PRENATAL DIAGNOSIS, Issue 13 2007
    Lars Jarup
    Abstract Objectives The aim of the study was to examine the risk of giving birth to a child with Down syndrome associated with residence near landfill sites in England and Wales. Methods A 2-km zone around 6289 landfill sites processing special (hazardous), non-special and unknown waste type was used to indicate exposure. Postcodes within the 2-km zone were classified as ,exposed' and people living beyond 2 km comprised the reference population. Health outcome data were Down syndrome registrations from a national registry including 21 cytogenetic laboratories in England and Wales, for the years 1989 to 1998. With a Bayesian regression model, we calculated relative risks for the population living within 2 km of landfill sites relative to the reference population, assuming a common relative risk for all landfill sites. Adjustments were made for major confounders. Results There were 4640 cases of Down syndrome within 2 km of a landfill site. We found no excess risks of Down syndrome related to landfill sites. Adjustment for socio-economic status (SES) did not influence our estimates. There were no differences in risk between hazardous waste sites and other landfill sites. Conclusion We found no excess risk of Down syndrome in populations living near landfill sites. Copyright © 2007 John Wiley & Sons, Ltd. [source]


    Legal and technical defensibility of data and the Triad approach

    REMEDIATION, Issue 2 2005
    Robert Howe
    The Triad approach was developed primarily to limit decision uncertainty during cleanups at hazardous waste sites. The fundamental principles of the Triad approach include development of a site characterization model and use of emerging technologies, which can provide data at a higher density than could be affordably collected using traditional data collection methodologies, to refine the model in essentially real time. New data formats are used collaboratively with data in traditional formats to iteratively pin down the relative concentration, nature, and extent of contaminants, thus minimizing decision uncertainties. This article examines the potential admissibility as evidence in legal proceedings of data collected by technologies designed to improve the density of information that are commonly used during the course of Triad-type projects. The article explains that such criteria may vary depending on the purpose for which the evidence is to be used (e.g., as direct evidence to prove site conditions or as support for the testimony of an expert witness) and the court in which the legal proceeding would take place (e.g., federal court or state court). Admissibility in federal courts of data both as direct evidence and as support for expert witness testimony is covered. © 2005 Wiley Periodicals, Inc. [source]


    In Situ solidification,A case study at a former manufactured gas plant in Macon, Georgia

    REMEDIATION, Issue 2 2004
    Jim Oosterhoudt
    In situ solidification (ISS) is a reliable, EPA-recognized technology for the treatment of industrial and waste sites. ISS was employed at a former manufactured gas plant (MGP) site in Macon, Georgia, for the treatment of approximately 33,000 cubic yards of coal tar residues in the saturated zone soil. The site is regulated by the Georgia Environmental Protection Division (EPD) under the Hazardous Site Rehabilitation Act (HSRA) and is located approximately four blocks from downtown Macon. This article will review the technical and regulatory basis for the successful use of this technology, provide an overview of the treatability and pilot testing used to develop the design and implementation of the treatment process, and present the results of the application of ISS to an MGP site. The results of groundwater monitoring, pre and postremediation, will also be discussed. © 2004 Wiley Periodicals, Inc. [source]


    Choosing remediation and waste management options at hazardous and radioactive waste sites

    REMEDIATION, Issue 1 2002
    Michael Greenberg
    This article discusses a process for finding insights that will allow federal agencies and environmental professionals to more effectively manage contaminated sites. The process is built around what Etzioni (1968) called mixed-scanning, that is, perpetually doing both comprehensive and detailed analyses and periodically re-scanning for new circumstances that change the decision-making environment. The article offers a checklist of 127 items, which is one part of the multiple-stage scanning process. The checklist includes questions about technology; public, worker, and ecological health; economic cost and benefits; social impacts; and legal issues. While developed for a DOE high-level radioactive waste application, the decision-making framework and specific questions can be used for other large-scale remediation and management projects. © 2002 Wiley Periodicals, Inc. [source]


    Analytical, Risk Assessment, and Remedial Implications Due to the Co-Presence of Polychlorinated Biphenyls and Terphenyls at Inactive Hazardous Waste Sites

    REMEDIATION, Issue 1 2000
    James J. Pagano
    Investigations conducted at three inactive hazardous waste sites in New York State have confirmed the co-presence of polychlorinated hiphenyls (PCBs) and polychlorinated terphenyls (PCTs) in soils, sediments, and biota. The PCTs at all three sites were positively identified as Aroclor 5432, with the most probable source being the hydraulic fluid Pydraul 312A utilized for high-temperature applications. The identification of the lower-chlorinated PCT formulations in environmental samples is problematical, since PCT Aroclors 5432 and 5442 are not chromatographically distinct from the higher-chlorinated (PCB) Aroclors 1254, 1260, 1262, and 1268 using conventional gas chromatography,electron capture detection. Results from this study indicate that U.S. Environmental Protection Agency (USEPA) approved PCB methods routinely utilized by most commercial laboratories based on Florisil adsorption column chromatography cleanup are inadequate to produce valid chromatographic separation and quantitative results with soils, sediment, and biota samples containing both PCBs and PCTs. The presence of co-eluting PCBs and PCTs precludes accurate quantitation due to significant differences in PCB/PCT electron capture detector response factors, and the potential for misidentification of PCT Aroclors as higher chlorinated PCB Aroclors. A method based on alumina column adsorption chromatography was used, allowing for the accurate identification and quantitation of PCB and PCT Aroclors. The results of this study suggest that the utilization of alumina adsorption column separation may have applicability and regulatory significance to other industrially contaminated sites which historically used Pydraul 312A. Inferences. [source]