Phytoforensics: Applications in Vapor Intrusion Assessment PDF Download

Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Phytoforensics: Applications in Vapor Intrusion Assessment PDF full book. Access full book title Phytoforensics: Applications in Vapor Intrusion Assessment by Jordan Lee Wilson. Download full books in PDF and EPUB format.

Phytoforensics: Applications in Vapor Intrusion Assessment

Phytoforensics: Applications in Vapor Intrusion Assessment PDF Author: Jordan Lee Wilson
Publisher:
ISBN:
Category :
Languages : en
Pages : 128

Book Description
"Vapor intrusion (VI) occurs when contaminants in the vapor phase migrate in the shallow subsurface and enter buildings through cracks, seams, and gaps and has been recognized as a serious human-health threat as occupants are exposed to potentially harmful concentrations over long periods of time. The VI pathway has recently (2017) been identified as a primary exposure pathway and implemented into the Hazard Ranking System for inclusion on the Nation Priorities List. However, assessing VI and human exposure is not simple and current methods are time-, cost-, and labor-intensive; intrusive; and temporally and spatially variability. Trees are ideal candidates for environmental biomonitors because they are ubiquitous, active samplers of vapor and groundwater and because they are thought to sample over large spatial and temporal scales, effectively averaging variability. Sampling trees is noninvasive and does not require the construction of sampling ports in homes, increasing the likelihood of obtaining property access and VI data. Tree samples are representative of the shallow subsurface with a footprint similar to a residential building. Directional tree sampling can also be used to elucidate shallow subsurface contamination from a single tree, and tree sampling is shown to be correlated with VI samples, especially when environmental samples are averaged over months and years. However, non-uniform distributions of tree-core samples likely resulted in large interpolation error in areas where trees are sparse. Although these findings demonstrate that tree sampling can augment traditional VI assessment methods, tree sampling is best applied as a screening tool because of the many parameters, and their associate uncertainties, that control mass transfer of contaminants in the subsurface and entry into plants and the built environment"--Abstract, page iv.

Phytoforensics: Applications in Vapor Intrusion Assessment

Phytoforensics: Applications in Vapor Intrusion Assessment PDF Author: Jordan Lee Wilson
Publisher:
ISBN:
Category :
Languages : en
Pages : 128

Book Description
"Vapor intrusion (VI) occurs when contaminants in the vapor phase migrate in the shallow subsurface and enter buildings through cracks, seams, and gaps and has been recognized as a serious human-health threat as occupants are exposed to potentially harmful concentrations over long periods of time. The VI pathway has recently (2017) been identified as a primary exposure pathway and implemented into the Hazard Ranking System for inclusion on the Nation Priorities List. However, assessing VI and human exposure is not simple and current methods are time-, cost-, and labor-intensive; intrusive; and temporally and spatially variability. Trees are ideal candidates for environmental biomonitors because they are ubiquitous, active samplers of vapor and groundwater and because they are thought to sample over large spatial and temporal scales, effectively averaging variability. Sampling trees is noninvasive and does not require the construction of sampling ports in homes, increasing the likelihood of obtaining property access and VI data. Tree samples are representative of the shallow subsurface with a footprint similar to a residential building. Directional tree sampling can also be used to elucidate shallow subsurface contamination from a single tree, and tree sampling is shown to be correlated with VI samples, especially when environmental samples are averaged over months and years. However, non-uniform distributions of tree-core samples likely resulted in large interpolation error in areas where trees are sparse. Although these findings demonstrate that tree sampling can augment traditional VI assessment methods, tree sampling is best applied as a screening tool because of the many parameters, and their associate uncertainties, that control mass transfer of contaminants in the subsurface and entry into plants and the built environment"--Abstract, page iv.

Vapor Intrusion Simulations and Risk Assessments

Vapor Intrusion Simulations and Risk Assessments PDF Author: Yijun Yao
Publisher: Springer Nature
ISBN: 9811927006
Category : Science
Languages : en
Pages : 133

Book Description
This book introduces key concepts in modeling and risk assessments of vapor intrusion, a process by which the subsurface volatile contaminants migrate into the building of concern. Soil vapor intrusion is the major exposure pathway for building occupants to chemicals from the subsurface, and its risk assessments determine the criteria of volatile contaminants in soil/groundwater in brownfield redevelopment. The chapters feature the recent advances in vapor intrusion studies and practices, including analytical and numerical modeling of vapor intrusion, statistical findings of United States Environmental Protection Agency’s Vapor Intrusion Database and Petroleum Vapor Intrusion Databases, the challenges of preferential pathways, and the application of building pressure cycling methods, and field practices of vapor intrusion risk assessments at developed contaminated sites and in brownfield redevelopment. This volume also summarizes the advantages and limits of current applications in vapor intrusion risk assessment, laying the groundwork for future research of better understanding in risk characterization of soil vapor intrusion using models. Written by experts in this field, Vapor Intrusion Simulations and Risk Assessments will serve as an invaluable reference for researchers, regulators, and practitioners, who are interested in perceiving the basic knowledge and current advances in risk assessments of soil vapor intrusion.

Evaluation of Vapor Intrusion Pathway Assessment Through Long-term Monitoring Studies

Evaluation of Vapor Intrusion Pathway Assessment Through Long-term Monitoring Studies PDF Author: Chase Weston Holton
Publisher:
ISBN:
Category : Chlorine compounds
Languages : en
Pages : 334

Book Description
Vapor intrusion (VI) pathway assessment often involves the collection and analysis of groundwater, soil gas, and indoor air data. There is temporal variability in these data, but little is understood about the characteristics of that variability and how it influences pathway assessment decision-making. This research included the first-ever collection of a long-term high-frequency indoor air data set at a house with VI impacts overlying a dilute chlorinated solvent groundwater plume. It also included periodic synoptic snapshots of groundwater and soil gas data and high-frequency monitoring of building conditions and environmental factors. Indoor air trichloroethylene (TCE) concentrations varied over three orders-of-magnitude under natural conditions, with the highest daily VI activity during fall, winter, and spring months. These data were used to simulate outcomes from common sampling strategies, with the result being that there was a high probability (up to 100%) of false-negative decisions and poor characterization of long-term exposure. Temporal and spatial variability in subsurface data were shown to increase as the sampling point moves from source depth to ground surface, with variability of an order-of-magnitude or more for sub-slab soil gas. It was observed that indoor vapor sources can cause subsurface vapor clouds and that it can take days to weeks for soil gas plumes created by indoor sources to dissipate following indoor source removal. A long-term controlled pressure method (CPM) test was conducted to assess its utility as an alternate approach for VI pathway assessment. Indoor air concentrations were similar to maximum concentrations under natural conditions (9.3 [micro]g/m3 average vs. 13 [micro]g/m3 for 24 h TCE data) with little temporal variability. A key outcome was that there were no occurrences of false-negative results. Results suggest that CPM tests can produce worst-case exposure conditions at any time of the year. The results of these studies highlight the limitations of current VI pathway assessment approaches and demonstrate the need for robust alternate diagnostic tools, such as CPM, that lead to greater confidence in data interpretation and decision-making.

Assessment of Mitigation Systems on Vapor Intrusion

Assessment of Mitigation Systems on Vapor Intrusion PDF Author: RTI International
Publisher:
ISBN:
Category :
Languages : en
Pages :

Book Description


A Proposed Guidance for Addressing Vapor Intrusion as a Component of Superfund's Hazard Ranking System

A Proposed Guidance for Addressing Vapor Intrusion as a Component of Superfund's Hazard Ranking System PDF Author: Jeff Polubinski
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

Book Description
For decades, scientists have propounded on the risks of vapor intrusion, the process by which contaminants present in soil and groundwater migrate, via volatilization, into buildings and affect indoor air quality. After years of deliberation, the United States Environmental Protection Agency (USEPA) has now added a vapor intrusion component to the Hazard Ranking System (HRS). The USEPA uses the HRS to evaluate whether a site warrants inclusion on the agency's National Priorities List (NPL) for Superfund sites. While the inclusion of vapor intrusion on the HRS is a positive, albeit overdue, development in Superfund law, how USEPA structures and implements the vapor intrusion component into the existing HRS will determine whether this new enhancement will actually prove to be protective of human health. First, this note will examine the concept of vapor intrusion. Included in this discussion will be a description of the contaminants at play, how vapors enter buildings, where vapor intrusion sites are located, what the human health risks are and, lastly what is done to mitigate the risks that vapor intrusion presents. The note will then discuss the importance that vapor intrusion plays in the Brownfields, Superfund and the LEED-certified building discussion and why vapor intrusion is often identified as an environmental justice issue. Next, the note will discuss many of the difficulties facing vapor intrusion regulation and the roadblocks that may have inhibited the promulgation of federal regulation earlier. I will then describe the different ways states have regulated vapor intrusion by assessing two enforcement mechanisms used by states in regulating sites where vapor intrusion may be an issue. First, I will evaluate how states initially assess vapor intrusion versus how states assess other more regulated exposure pathways (such as ingestion of contaminated drinking water). If there is some sort of ranking or prioritization of sites, what weight, if any, is given to sites where vapor intrusion is an issue? Secondly, I will look at what steps states take, or require potentially responsible parties or responsible parties to take, when vapor intrusion has been identified. Lastly, based on components of state regulation, I will propose a regulatory framework for addressing vapor intrusion.

Vapor Intrusion Risk Assessment With an Innovative Mobile GC System

Vapor Intrusion Risk Assessment With an Innovative Mobile GC System PDF Author: Bernd Seelhorst
Publisher:
ISBN:
Category : Flux chamber
Languages : en
Pages : 16

Book Description
One of the dominating problems in the revitalization of brownfields in region of São Paulo City, Brazil, is the assessment and quantification of vapor intrusion scenarios that trigger frequently necessary remedial actions. With a flux chamber based investigation procedure in combination with a new developed GC-system for the detection of chlorinated volatile organic compounds (CVOCs) site specific soil vapor fluxes could be quantified. Based on the results of flux chamber experiments the effectiveness of concrete slabs could be shown to reduce the vapor flux into enclosed spaced. Moreover, the obtained vapor flux rates were used to predict resulting indoor air concentration due to vapor intrusion of CVOCs.

Reference Handbook for Site-specific Assessment of Subsurface Vapor Intrusion to Indoor Air

Reference Handbook for Site-specific Assessment of Subsurface Vapor Intrusion to Indoor Air PDF Author: Todd A. McAlary
Publisher:
ISBN:
Category : Hazardous waste sites
Languages : en
Pages : 231

Book Description


Vapor Intrusion at a Site with an Alternative Pathway and a Fluctuating Groundwater Table

Vapor Intrusion at a Site with an Alternative Pathway and a Fluctuating Groundwater Table PDF Author: Yuanming Guo
Publisher:
ISBN:
Category : Indoor air pollution
Languages : en
Pages : 310

Book Description
Vapor intrusion (VI), can pose health risks to building occupants. Assessment and mitigation at VI impacted sites have been guided by a site conceptual model (SCM) in which vapors originate from subsurface sources, diffuse through soil matrix and enter into a building by gas flow across foundation cracks. Alternative VI pathways and groundwater table fluctuations are not often considered. Alternative VI pathways, involving vapor transport along sewer lines and other subsurface infrastructure, have recently been found to be significant contributors to VI impacts at some sites. This study evaluated approaches for identifying and characterizing the significance of alternative VI pathways and assessed the effectiveness of conventional mitigation at a site with an alternative VI pathway that can be manipulated to be on or off. The alternative pathway could not be identified using conventional pathway assessment procedures and can only be discovered under controlled pressure method (CPM) conditions. Measured emission rates were two orders of magnitude greater than screening model estimates and sub-foundation vertical soil gas profiles changed and were no longer consistent with the conventional VI conceptual model when the CPM test was conducted. The pipe flow VI pathway reduced the vacuum performance of the sub-slab depressurization (SSD) VI mitigation system, but the SSD system still provided sufficient protection to the house. The relationship between groundwater table fluctuations and subsurface vapor emissions and transport is examined using multi-year data from the field site, and is studied in the laboratory. In addition, a broader range of conditions is examined through use of modeling validated with the experimental data. The results indicate that fluctuating groundwater tables will lead to amplified volatile organic chemical (VOC) emissions from groundwater to soil surface relative to steady water table elevation, however, the magnitude of this amplification is less concerned when long-term water fluctuation present. No clear correlations were found between VOC emissions and water table changes at the study site where annual water table fluctuations of about 0.3 m existed. Significant VOC emission amplifications by water table fluctuation would be expected under shallow groundwater conditions according to model analysis results.

Phyto

Phyto PDF Author: Kate Kennen
Publisher: Routledge
ISBN: 1317599012
Category : Architecture
Languages : en
Pages : 378

Book Description
Winner of the 2017 CBHL Literature Award of Excellence in Landscape Design and Architecture Phyto presents the concepts of phytoremediation and phytotechnology in one comprehensive guide, illustrating when plants can be considered for the uptake, removal or mitigation of on-site pollutants. Current scientific case studies are covered, highlighting the advantages and limitations of plant-based cleanup. Typical contaminant groups found in the built environment are explained, and plant lists for mitigation of specific contaminants are included where applicable. This is the first book to address the benefits of phytotechnologies from a design point of view, taking complex scientific terms and translating the research into an easy-to-understand reference book for those involved in creating planting solutions. Typically, phytotechnology planting techniques are currently employed post-site contamination to help clean up already contaminated soil by taking advantage of the positive effects that plants can have upon harmful toxins and chemicals. This book presents a new concept to create projective planting designs with preventative phytotechnology abilities, ‘phytobuffering’ where future pollution may be expected for particular site programs. Filled with tables, photographs and detailed drawings, Kennen and Kirkwood's text guides the reader through the process of selecting plants for their aesthetic and environmental qualities, combined with their contaminant-removal benefits.

Fate and Transport of Subsurface Pollutants

Fate and Transport of Subsurface Pollutants PDF Author: Pankaj Kumar Gupta
Publisher: Springer Nature
ISBN: 9811565643
Category : Science
Languages : en
Pages : 348

Book Description
This volume offers detailed information on the behaviour of various water pollutants, and on the principles and concepts of groundwater flow and transport. It will help readers to understand and execute the planning, supervision, and review of solute transport and groundwater modeling projects. The book also discusses the role and fate of elements that have been identified as major contaminants in surface and subsurface waters, and their adverse effects on ecology and human health. The book explores this theme throughout four sections – a. Understanding Soil-Water Systems, b. Fate and Transport of Pollutants, c. Physico-Chemical Treatment of Wastewater and d. Microbial Techniques Used to Decontaminate Soil-Water Systems. Introducing readers to a range of recent advances concerning the fundamentals of subsurface water treatment, it offers a valuable guide for teachers, researchers, policymakers, and undergraduate and graduate students of hydrology, environmental microbiology, biotechnology and the environmental sciences. It also provides field engineers and industrial practitioners with essential support in the effective remediation and management of polluted sites.