The HEER office webinar series was launched in 2015 to provide training to State, County and Federal Agencies along with the environmental consultant community to develop a shared understanding of the latest scientific, technical, and policy development affecting cleanups in Hawai'i. Audio PowerPoint recordings of some webinars are posted to the HEER Office HEER Office YouTube Channel. Links to specific webinar recordings are also provided below.

If you would like to be included in future webinar and HEER office guidance update notifications then please contact Roger Brewer with the HEER office at roger.brewer@doh.hawaii.gov. We keep emails at a minimum and will not pass your address on to outside parties.

July 16, 2019. Fake Data? Sampling Theory and Environmental Investigations

This webinar, presented by Roger Brewer with the Hawaii Department of Health to the State Risk Assessors association, describes how “highly variable” environmental sample data are tied in part the misapplication of “discrete” sampling methods for “finite element media,” such as a group of people or cans of tuna fish, to testing of “infinite element media” such as soil, water and air. Such data can cause significant uncertainty in estimates of risk posed by contaminated media as well as uncertainty in the design and adequacy of remedial actions. The webinar introduces sampling approaches based on Gy’s sampling theory for infinite element media and uses examples for air, soil vapor, soil and sediment to demonstrate how the inherent, heterogeneous nature of contaminants in the environment can be controlled and more reliable data collected to assess risk and determine appropriate actions.

February 20, 2019. DU-MIS Overview and Risk-Based Site Characterization

This webinar by Roger Brewer with the Hawaii Department of Health provides a broad-based overview of the use of DU-MIS investigation method to characterize contaminated soil and sediment. Time Tags to skip to specific sections in the webinar are provided below. Emphasis is placed on the incorporation of risk assessment as well as remediation efficiency needs in the initial design of a site investigation. Causes behind the inability of traditional, "discrete sample" data to efficiently and reliably characterize contaminated sites are discussed.

September 20, 2018. DU-MIS for Sediments (Roger Brewer)

This webinar webinar was originally presented to sediment specialists in USEPA regional offices on September 20, 2018, The webinar discusses the use of “Decision Unit” and “Multi Increment Sample” (DU-MIS) investigation methods for characterization of contaminated sediment.

The presentation begins with a discussion of the nature and causes of “discrete” sample data unreliability. This is followed by a general discussion of DU-MIS investigation methods and a series of case studies from Hawaii that describe the use of these methods to investigate sediment under different settings.Topics discussed include the designation of Decision Units for initial site screening, ecological risk assessment and optimization of remediation as well as approaches for the collection of samples from different types of sediment and in shallow versus deep water.

PowerPoint Slides (click on presentation title to download):

DU-MIS for Sediments PPT Slides (Sept 20 2018)

August 30, 2018. DU-MIS for PCBs (Roger Brewer)

This two-part webinar was presented to USEPA PCB coordinators who work under TSCA regulations. A former Voice of America broadcasting station is used as a case study for the use of discrete vs Multi Increment sampling methods to characterize and remediate PCB-contaminated soil. The site was part of a detailed field study carried out bu HIDOH to investigate the reliability of discrete sample data. Part 1 of the webinar, held August 30, 2018, reviews the history of the site and the results of the discrete sample reliability study. The data are compared to "DU-MIS" data collected from the same area. The discrete and initial DU-MIS data were then used to design a detailed, DU-MIS based remedial action plan.

Part 2 of the study, scheduled for October 2018, will review the results of the remediation action and discuss what the consultants learned and might do differently for the next project.

Links to PowerPoint slides and a recording of the presentation posted to the HEER Office YouTube channel will be posted below as available.

August 2018. TPH Risk Case Studies (Roger Brewer)

This two-part webinar reviews the basics of the risk-based use of TPH data to investigate, remediate and manage petroleum contaminated soil and groundwater. Detailed notes and discussions are provided in the accompanying document (last updated August 2018). The case studies in large part reflect current, HIDOH guidance but were prepared with input from multiple, outside state and federal regulators as well as private consultants and experts associated with the petroleum industry. The primary authors, Roger Brewer with the HIDOH and Manivannan (Mani) Nagaiah with Langan Engineering & Environmental Services, Inc., are also active members of the Interstate Technology & Regulatory Council (ITRC) (TPH Risk work group) and acknowledge important contributions to the document from many of the ITRC team members. The HDOH Case Studies will be referenced in the ITRC TPH Risk document for examples of the site-specific use of TPH data in a variety of petroleum-release scenarios (anticipated early 2019).

Links to download the Webinar PowerPoint slides and the HIDOH TPH Risk Cast Study report are posted below. Links to recordings of the webinars posted to the HEER Office YouTube web page will be provided when ready. The final PowerPoint slides used in the webinars were posted August 29, 2018.

December 2017. Use of ESLs and DU-MIS to Expedite Site Investigation and Remediation (Roger Brewer)

This webinar discussed the combined use of Environmental Screening Levels and Decision Unit/Multi Increment Sample methods to expedite the investigation and remediation of contaminated properties. The webinar was held for USEPA Region 9 staff and visiting delegates from the China Ministry of Environment. Slides used for the presentation are posted below. Chinese translation included on slides.

November 21, 2017, EHE Webinar (Roger Brewer)

PowerPoint slides and link to recorded presentation for Roger Brewer's webinar on Environmental Hazard Evaluation (EALs/ESLs) are posted below.

November 13, 2017, TPH Forensics Workshop (Ileana Rhodes)

PowerPoint slides for Ileana Rhodes’ seminar on TPH Forensics are posted below. Ileana Rhodes gave an introduction to forensic analysis of petroleum related contamination. Discussions included how to read and understand TPH chromatograms and how to distinguish petrogenic from pyrogenic PAHs. Site examples complemented the discussion. Ileana explained the Texas Method of analyzing TPH and included an example.The HEER Office is considering a recommendation for use of the Texas laboratory method for TPH in Hawaii.

November 15, 2017, Multi Increment Samples - Laboratory Processing (Diane Anderson)

This webinar presents an overview of laboratory processing of Multi Increment soil and sediment samples. The webinar was presented on November 15th, 2017, by Diane Anderson APPL Laboratories.

October 2017 LNAPL Conceptual Site Models (Gary Beckett)

LNAPL scientist and industry expert G.D. Beckett from Aqui‐Ver, Inc. held a half-day workshop on LNAPL (Light‐Non‐Aqueous Phase Liquid) Conceptual Site Models (LCSMs) at the HEER Office on October 11, 2017. A pdf copy of the workshop presentations is posted below. LCSMs are the foundation for site assessment and site remediation decisions; therefore, a useful and detailed LCSM using easily available standard data or more advanced data collection for complex sites is key. Topics discussed included LNAPL distribution in the subsurface, factors that drive LNAPL distribution, and guidance on characterization and remediation. The workshop included theoretical aspects of LNAPL fate and transport in the subsurface as well as numerous field examples and practical guidance for implementation.

September 2017. Tapwater Screening Levels for TPH-Related Metabolites (Roger Brewer)

PowerPoint slides for presentation given to ITRC TPH Risk work group on the potential calculation of toxicity-based, metabolite suite-weighted screening levels for TPH-related degradation compounds in drinking water. Refer to Attachment 5 in HDOH Document "Collection and Use of Total Petroleum Hydrocarbon Data for the Risk-Based Evaluation of Petroleum Releases - Example Case Studies (August 2018)" for details.

August 2017 - Discrete Soil Sample Reliability (USEPA Incremental Sampling Committee)

Below are links to PowerPoint slides and a YouTube recording for presentation on Discrete Soil Sample Reliability give to the USEPA Incremental Sampling Committee August 3, 2017, by Roger Brewer (Hawaii Dept of Health). 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 HDOH 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 and Fact Sheet web page for links to HEER Office Technical Guidance Manual (TGM) as well as reports, presentations and published papers related to the HDOH 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.

Recorded Presentations (YouTube; click on presentation title)
1. Discrete Sample Reliability (RBrewer Aug 3, 2017)

PowerPoint Slides:

June-November 2017 - Decision Unit - Multi Increment Sample Investigation Methods Webinars

John Peard and Roger Brewer of the HEER office presented a four-part webinar series June 26-29, 2017, on the use of DU-MIS methods for the investigation of contaminated soil and sediment. The webinars review Section 3 (Systematic Planning and DU Designation), Section 4 (Sampling Theory and DU Characterization) and Section 5 (Field Implementation) of the HEER Office Technical Guidance Manual (TGM).

Recordings of the webinars are posted to the HEER Office YouTube channel (separate recordings include Chinese Subtitles). Links to the recordings are embedded in the webinar titles below:

Part 1. Systematic Planning
Part 2: Decision Unit Designation
Part 3: Decision Unit Characterization (Sampling Theory, Discrete vs Multi Increment Samples)
Part 4: Field Implementation of DU-MIS Investigation Methods
Part 5: Laboratory Processing and Testing
Part 6: Environmental Hazard Evaluation and EALs/ESL

PowerPoint presentations used in these webinars are available for download from the links below (PowerPoint slides for Part 4 Field Implementation split into two files due to large size). Try using another browser if you have trouble downloading the files. Google Chrome sometimes works better than Windows Explorer. Links to reports, PowerPoint presentations, recorded webinars and a two-part, published paper for the field study of discrete soil sample variability carried out by the HEER office in 2014-2015 are included in webinar postings dated October 7 & 15, 2015, further down this webpage.

June 2017 - Large Volume Purge Subslab Vapor Sampling Methods

The below presentation on “Large Volume Purge (LVP)” methods for the collection of subslab vapor samples was originally give to the Hawaii Association of Environmental Professionals (HAEP) by Roger Brewer of the HDOH 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 roger.brewer@doh.hawaii.gov.

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)

August 2016 - Role of Heterogeneity in Vapor Intrusion (California EPA)

Recording of a presentation by Roger Brewer with the HEER office to California EPA that discusses flaws in the USEPA "Empirical Vapor Intrusion Database" and the use of more robust studies of building leakage to estimate vapor intrusion attenuation factors in different climate settings.

May 2016 - Battelle Conference Presentations

Roger Brewer with the HEER Office presented overviews of field studies of Petroleum Vapor Intrusion and Discrete Soil Sample Reliability at the Battelle Tenth International environmental remediation conference in Palm Springs, California, in May. Audio recordings of the presentations (YouTube) and slides (PowerPoint) can be accessed at the links 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 this summer. Contact Roger Brewer for additional information (roger.brewer@doh.hawaii.gov).

October 21, 2015 - Field Study of Discrete Soil Sample Variability and Reliability: Part 2 - Implications

Roger Brewer of the HEER office 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.

October 7, 2015 - Field Study of Discrete Soil Sample Variability and Reliability: Part 1 - Results

Roger Brewer of the HEER office reviews the objectives, design and results of a 2014, HDOH 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.

September 3, 2015 - Discrete vs Incremental Samples Explained Using Salad

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, VA, on September 3, 2015. Updated September 19, 2015, to include notes on the use of Incremental Sampling for PCBs under TSCA.

July 27, 2015 - Petroleum Vapor Intrusion: Facts, Fallacies and Implications

Roger Brewer of the HEER office presented an update on Hawaii’s guidance for petroleum vapor intrusion (PVI), in light of recent guidance published by the USEPA 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.

May 11, 2015 - Recent Developments in Groundwater Bioremediation and Vapor Mitigation Technologies

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

April 15, 2015 - Long-Term Management of Contaminated Soil and Groundwater – Iwilei District, Honolulu

The Iwilei District encompasses approximately 315 acres of land in Honolulu and includes land owned privately and by the State of Hawaii. The Hazard Evaluation and Emergency Response (HEER) Office of the Hawaii Department of Health (HDOH) 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 Hawaii 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.

Steven Mow and Jordan Nakayama (HEER Office)

February 18, 2015 - Dungeons, Dragons, Pica Houses and the Need for Alternative, Vapor Intrusion Screening Tools

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.

Download Links

PowerPoint Presentation (without audio)
Webinar with Audio on YouTube

Roger Brewer, State of Hawaii, Department of Health, Hazard Evaluation and Emergency Response Office

The presenter is a coauthor of the following paper on vapor intrusion attenuation factors recently published by HDOH staff.
Brewer, R., Nagashima, J., Rigby, M., Schmidt, M. and O'Neill, H. (2014), Estimation of Generic Subslab Attenuation Factors for Vapor Intrusion Investigations. Groundwater Monitoring & Remediation, 34: 79–92. doi: 10.1111/gwmr.12086, http://onlinelibrary.wiley.com/doi/10.1111/gwmr.12086/full

March 11, 2015 - Use of Active and Passive Soil Gas Samples to Support 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 with 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.

Download Links

Overview of VI Webinar
Roger Brewer
PowerPoint Presentation no audio
Webinar with Audio on YouTube
Active Soil Gas Sampling
Mort Schmidt
PowerPoint Presentation no audio
Webinar with Audio on YouTube
Passive Soil Gas Sampling
Harry O’Neil
PowerPoint Presentation no audio
Webinar with Audio on YouTube


Roger Brewer, State of Hawaii, Department of Health, Hazard Evaluation and Emergency Response 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.

2013 - Behavior of LNAPL and Subsurface Oil Plumes

The Behavior of Sub-Surface Oil Plumes, in the Real World . . .And some practical observations on how to manage them.

Pat Hughes, former head of the Hawaii Chevron environmental office gave a presentation in April 2013 on LNAPL mobility and related topics. This presentation was based in part on studies that were carried out in the IDPP, Honolulu Harbor area in coordination with the HEER office. The presentation is now available through the above link.