Hazard Evaluation and Emergency Response Office

This presentation is similar to other, recent presentations given by Roger Brewer and John Peard on this subject but more focused on the results and implications of the DOH field study of discrete sample variability, with a short comparison of discrete vs Multi Increment sampling methods at the end. As in all posted HEER Office webinars, the slides and presentations are not copyrighted and can be used as desired without permission from the authors. Links to related DU-MIS presentations hosted or otherwise recommended by the HEER Office are included elsewhere on this webpage.

Refer to the four-part, training series series posted in June 2017 for a detailed overview of DU-MIS investigation methods, including: 1) Systematic Planning of Site Investigations, 2) Designation of Decision Units, 3) Sampling theory and characterization of DUs (discrete vs MIS) and 4) DU-MIS field implementation. Refer to the Technical Guidance Manual and Fact Sheet web page as well as reports, presentations and published papers related to the DOH field study of discrete soil sample reliability (see also 2015 webinar postings below). The technical background and field implementation of DU-MIS investigation methods is discussed in Sections 3, 4 and 5 of the TGM.

• Discrete Sample Reliability (RBrewer Aug 3, 2017) PowerPoint Slides

The below presentation on “Large-Volume Purge (LVP)” methods for the collection of subslab vapor samples was originally give to the Hawaiʻi Association of Environmental Professionals (HAEP) by Roger Brewer of the HEER Office on June 28, 2017. The slides and recorded presentation were subsequently modified to incorporate comments and questions received during the original presentation. A discussion of LVP sampling methods will be added to Section 7 of the HEER Office Technical Guidance Manual later this year. Comments and suggestions are welcome and should be sent to [email protected]. The field report for the LVP study carried out in 2016 by the HEER Office is available for download from the link below. The report provides detailed diagrams of the equipment and methods used to collect both passive vapor samples and LVP vapor samples at the study site. Refer also to presentations on active and passive soil vapor sampling methods posted on this web page in March 2015.

• Field Study of High-Density Passive Sampler and Large-Volume Purge Methods to Characterize Subslab Vapor Plumes (HDOH 2017)
• PowerPoint Presentation

Roger Brewer of the HEER Office presented an overview of field studies of Petroleum Vapor Intrusion at the Battelle 10th International environmental remediation conference in Palm Springs, California, in May 2016. Audio recordings of the presentation (YouTube) and slides (PowerPoint) can be accessed at the link below. The recordings and presentations include additional notes and ideas from discussions with environmental professionals subsequent to the conference, including a proposed HEER field study of subslab vapor plume heterogeneity and characterization planned for later. For additional information, contact Roger Brewer at [email protected].

• PVI Facts and Fallacies PowerPoint

Roger Brewer of the HEER Office reviews the objectives, design and results of a 2014 DOH field study of the variability of contaminant concentrations within individual discrete soil samples and between co-located samples and discusses initial implications for the use of discrete soil samples in environmental investigations. He then discusses how random, small-scale variability of contaminant concentrations in discrete soil samples can lead to erroneous estimations of the extent of contamination, false “hot spots” and “cold spots” on isoconcentration maps and uncertainty in the estimate of contaminant means for use in environmental risk assessments. The presentation concludes with a review of Decision Unit and Multi Increment investigation methods and the use of DU-MIS to characterize PCB-contaminated soil under TSCA.

Review of discrete vs incremental soil sampling methodologies and the basics of sampling theory, originally presented by Roger Brewer of the HEER Office at the AGC Conference in Arlington, Virginia, on September 3, 2015. Updated September 19, 2015, to include notes on the use of Incremental Sampling for PCBs under TSCA.

• PowerPoint Presentation

Roger Brewer of the HEER Office presented an update on DOH guidance for petroleum vapor intrusion (PVI), in light of recent guidance published by the US EPA and ITRC. Similarities and discrepancies in approaches to PVI were discussed, including a review the field study of the chemistry and toxicity of petroleum vapors carried out by the HEER Office in 2013.

• PowerPoint Presentation

Steve Nigro of Regenesis and Kelly Smith of Land Science Technologies were in Honolulu providing a presentation on their respective remedial technologies to DOH. This presentation focused on the science behind their technologies, best uses and a case study. The technologies discussed are Regenesis’s Plumestop and Land Science’s Geo-Seal and Retro-Coat Systems.

• PowerPoint Presentation

The Iwilei District encompasses approximately 315 acres of land in Honolulu and includes land owned privately and by the State of Hawaiʻi. The HEER Office is overseeing remediation of potentially hazardous contaminants of concern that are present in soil, groundwater, and soil gas at various locations within the Iwilei District. Widespread, shallow petroleum contamination related to past releases from tank farms and pipelines is the primary concern, but metals and pesticides are also present in some areas. The primary focus of this webinar is outreach for the HEER Office development and implementation of a programmatic Environmental Hazard Management Plan (EHMP) for the Iwilei District. This document details remedial measures and controls that are consistent with EHMPs implemented at other sites in Hawaiʻi where contamination is present. No further investigation or remedial action is required at many of these sites, provided that long-term site management requirements in the EHMP are followed.

Presenters

Steven Mow and Jordan Nakayama (HEER Office)

• PowerPoint Presentation

The presentation reviews current trends in the evaluation of vapor intrusion impacts to homes and buildings that overlie VOC-contaminated soil and groundwater. Implications for vapor intrusion guidance in Hawai’i as well as on the mainland is discussed.

Presenter: Roger Brewer, HEER Office

• PowerPoint Presentation

The presenter is a coauthor of the following paper on vapor intrusion attenuation factors recently published by DOH staff: Estimation of Generic Subslab Attenuation Factors for Vapor Intrusion Investigations

This HEER-sponsored webinar reviews current trends in the evaluation of vapor intrusion impacts to homes and buildings that overlie VOC-contaminated soil and groundwater. Roger Brewer of the HEER Office gives a brief overview of a webinar on vapor intrusion held February 18th, 2015. Martin Schmidt with Cox-Colvin, Inc., then provides an overview of active soil gas sampling methods and approaches to improve data quality for evaluation of vapor intrusion hazards. This was followed by a similar presentation on passive soil gas sampling methods by Harry O’Neill of Beacon Environmental, Inc. Topics addressed include the basics of active and passive soil gas sample collection, vapor plume heterogeneity and the use of larger numbers of samples and/or larger-volume samples to provide more reliable data for decision making. Implications for vapor intrusion guidance in Hawai’i as well as on the mainland were discussed.

• Overview of VI Webinar PowerPoint Presentation
• Active Soil Gas Sampling PowerPoint Presentation
• Passive Soil Gas Sampling PowerPoint Presentation

Presenters

Roger Brewer, HEER Office

Martin (Mort) Schmidt is currently Practice Leader for vapor intrusion for the consulting firm Cox-Colvin, & Associates in Plain City, Ohio, where he has been employed since 1997. Prior to Cox-Colvin, Mr. Schmidt served as a radon investigator for the Ohio EPA, a geologist for Geraghty and Miller (now Arcadis), and an exploration geologist for Shell International. Mort received his B.S. and M.S. degrees in Geology from the Ohio State University.

Harry O’Neill is the President of Beacon Environmental Services, which is an accredited laboratory and field sampling organization that specializes in the collection and analysis of soil gas and air samples. Mr. O’Neill has managed soil gas investigations for more than 20 years working on federal, state, and commercial projects throughout the United States, as well as internationally across six continents. Mr. O’Neill has been on the forefront of the acceptance of passive soil gas sampling technologies at the national and international level and has overseen the implementation of over a thousand soil gas surveys. He is a member of AWMA, ITRC, and ASTM, is the lead author of ASTM Standard D7758: Standard Practice for Passive Soil Gas Sampling, and has published and presented findings throughout the United States, as well as internationally.