1,4-Dioxane has seen widespread use as a solvent stabilizer since the 1950s. The widespread use of solvents through the 1980s suggests its presence at thousands of solvent sites in the US; however, it is not always a standard compound in typical analytical suites for hazardous waste sites, so it previously was overlooked. The U.S. EPA has classified 1,4-dioxane as "likely to be carcinogenic to humans." Some states have devised health standards or regulatory guidelines for drinking water and groundwater standards; these are often sub-part per billion values. These low standards present challenges for analysis, characterization, and remediation of 1,4-dioxane. The ITRC team created multiple tools and documents that provide information to assist all interested stakeholders in understanding this contaminate and for making informed, educated decisions.

The 1,4-Dioxane: Science, Characterization & Analysis, and Remediation training is a series of six (6) modules. The six individual modules will be presented together live, and then archived on the ITRC 1,4-Dioxane training webpage for on demand listening.

The modular 1,4-Dioxane training series provides an overview of 1,4-dioxane and presenting six sections from the ITRC guidance document (1,4d-1, 2021):

• History of Use and Potential Sources (Sect 1)
• Regulatory Framework (Sect 2)
• Fate and Transport (Sect 3)
• Sampling and Analysis (Sect 4)
• Toxicity and Risk Assessment (Sect 5)
• Remediation and Treatment Technologies (Sect 6)

• The history of 1,4-dioxane manufacturing and usage and the potential sources of releases of 1,4-dioxane to the environment.
• Primary state and U.S. federal regulatory programs of relevance to 1,4-dioxane
• Key physical/chemical properties, and fate and transport processes that are relevant for 1,4-dioxane
• Benefits and limitations of the available analytical methods
• Risk drivers for human health and how ecological risk compares
• How/when/why different treatment technologies are appropriate

Presenters:

Heather Barbare, P.E. CHMM, Colorado Department of Public Health and Environment (heather.barbare@state.co.us)
Introduction
Heather Barbare is an engineer with the Colorado Department of Public Health and Environment. Heather has worked for the CDPHE since 2015 and manages solid waste permitting projects. Prior to her work for the CDPHE, from 2014 to 2015, Heather worked for a local government managing solid waste projects and as an environmental planner. From 2005 to 2014, Heather worked as an environmental consultant specializing in remediation and environmental compliance. Heather earned a bachelor's degree in chemistry from the Colorado School of Mines and a master's of engineering degree from the University of Wisconsin - Madison. Heather is a professional engineer and a Certified Hazardous Materials Manager.

Gladys A. Liehr, PhD, CSM, Florida Department of Health (gladys.liehr@flhealth.gov)
Introduction
Gladys A. Liehr is the program lead for the Hazardous Waste Site Health Risk Assessment team within the Bureau of Environmental Health, Florida Department of Health. She is a biologist and risk assessor with over 14 years of experience. From a marine ecologist working on the Everglades Restoration project, to a regulator working for the Florida Department of Environmental Protection, and now working to protect, promote and improve the health of all people in Florida, she has conducted complex risk analysis, drafted guidance documents and health consultation, established standard operating procedures, and conducted numerous training, talks, and public availability sessions. Gladys has been involved with ITRC since 2016 and has been a member of multiple teams. She has been a co-leader for ITRC's 1,4-dioxane team and is ITRC's Point of Contact for the State for Florida. Gladys earned a Doctorate in Science from the University of Rostock, Germany in 2006.

William H. DiGuiseppi, Jacobs Solution (bill.diguiseppi@jacobs.com)
History of Use and Potential Sources & Regulatory Framework
Bill DiGuiseppi is a 30+ year experienced Principal Hydrogeologist with Jacobs in their Denver office. Bill is an expert in the history, occurrence and remediation of 1,4-dioxane and PFAS, and leads Jacobs Emerging Contaminants Community of Practice. Bill co-authored the definitive book on 1,4-dioxane with Tom Mohr, Janet Anderson, and Jim Hatton. He frequently conducts 1,4-dioxane and PFAS training for a variety of groups, including the US EPA, the US DOD, the US DOE and the Society of American Military Engineers (SAME). Bill has been actively engaged with the ITRC 1,4-Dioxane Team, as the history and use writing subgroup co-lead. Bill has also been an instructor on emerging contaminants topics for ITRC for several years. His enthusiastic support of ITRC earned him the 2018 Industry Member of the Year award. Bill is also an adjunct faculty member in the Civil and Environmental Engineering Department at the Colorado School of Mines.

Jim Hatton, Jacobs Solution (james.hatton@jacobs.com)
History of Use and Potential Sources
James W. Hatton is a principal technologist and senior engineer in Jacob's environmental remediation group in Englewood, Colorado. Jim has over 30 years of applied engineering experience at a wide variety of sites, addressing the investigation and remediation of emerging contaminants, chlorinated volatile organic compounds, metals, and petroleum. Mr. Hatton has worked with 1,4-dioxane since 1988, beginning at polyester manufacturing plants and has spent over 30 years investigating and remediating this compound.  His efforts include understanding the fate and transport of 1,4-dioxane and its potential for degradation and in situ and ex situ treatment by oxidation, biological and adsorption technology.  Mr. Hatton supports Jacob's emerging contaminants program and is the lead remediation engineer for programs addressing 1,4-dioxane and PFAS treatment in groundwater. Mr. Hatton is a co-author of Environmental Investigation and Remediation: 1,4-Dioxane and Other Solvent Stabilizers (Second Edition). Mr. Hatton received his BS in petroleum engineering from West Virginia University in Morgantown, West Virginia.

Janet Anderson, Ph.D., DABT, GSI Environmental Inc. (jkanderson@gsi-net.com)
Regulatory Framework & Toxicology and Risk Assessment
Dr. Janet Anderson is a Principal Toxicologist with GSI Environmental Inc. with 15 years of experience providing toxicology and risk management strategies to federal agencies, private industry, and municipal clients. She also provides litigation consulting and expert services and is a Diplomate of the American Board of Toxicology. Dr. Anderson specializes in communicating the key findings from toxicology studies used to inform state and federal regulatory policy and public health decisions, and helping stakeholders understand the sometimes-disparate interpretations. She is a recognized leader in unregulated and emerging chemicals, such as per- and polyfluoroalkyl substances (PFAS), 1,4-dioxane, and 1,2,3-trichloropropane. She has developed strategies to mitigate human health risks and address environmental liability associated with unregulated and emerging chemicals for both private and public sector clients. She has extensive experience developing risk communication and risk management strategies for multi-stakeholder groups. Dr. Anderson received her Ph.D. in Molecular and Cancer Biology from the University of Cincinnati, completed a post-doctoral fellowship with the U.S. Environmental Protection Agency, and as a civilian government employee, led the U.S. Air Forces Emerging Contaminants program and advised the Department of Defense on matters related to toxicology and environmental restoration. A skilled communicator, Dr. Anderson is often an invited speaker and panelist at high-level scientific conferences, regulatory and industry meetings, law seminars, technical webinars and workshops, and community stakeholder meetings.

William H. DiGuiseppi, Jacobs Solution (bill.diguiseppi@jacobs.com)
Regulatory Framework
Bill DiGuiseppi is a 30+ year experienced Principal Hydrogeologist with Jacobs in their Denver office. Bill is an expert in the history, occurrence and remediation of 1,4-dioxane and PFAS, and leads Jacobs Emerging Contaminants Community of Practice. Bill co-authored the definitive book on 1,4-dioxane with Tom Mohr, Janet Anderson, and Jim Hatton. He frequently conducts 1,4-dioxane and PFAS training for a variety of groups, including the US EPA, the US DOD, the US DOE and the Society of American Military Engineers (SAME). Bill has been actively engaged with the ITRC 1,4-Dioxane Team, as the history and use writing subgroup co-lead. Bill has also been an instructor on emerging contaminants topics for ITRC for several years. His enthusiastic support of ITRC earned him the 2018 Industry Member of the Year award. Bill is also an adjunct faculty member in the Civil and Environmental Engineering Department at the Colorado School of Mines.

David T. Adamson, Ph.D, P.E., GSI Environmental Inc. (dtadamson@gsienv.com)
Environmental Fate, Transport and Investigation Strategies
Dr. David Adamson is a Principal Engineer at GSI Environmental Inc. in Houston, Texas with more than 20 years of environmental project experience in academic research and environmental consulting. He has extensive expertise in projects dealing with natural attenuation, high-resolution site characterization, emerging contaminants, matrix diffusion, and the development and testing of innovative monitoring and remediation technologies. He has served as a Principal Investigator or co-Principal Investigator on several DoD-sponsored research projects, including those focused on PFAS and 1,4-dioxane treatment and fate and transport. He is an active member of both the PFAS team and the 1,4-Dioxane team for ITRC, serving as the co-lead of the Training Group for the 1,4-Dioxane team as well as a contributing author for both team's guidance documents. He is a licensed Professional Engineer in Texas and serves as a Lecturer at Rice University in the Civil and Environmental Engineering Department.

Monica Heintz, Arcadis (monica.heintz@arcadis.com)
Environmental Fate, Transport and Investigation Strategies
Dr. Monica Heintz is a Principal Geoscientist at Arcadis U.S., Inc. in Denver, Colorado. She has more than 15 years of experience in academic research and environmental consulting. Dr. Heintz works at the nexus of groundwater hydrogeology, geochemistry, and microbiology. She has extensive project experience developing and refining conceptual site models and designing, implementing, and evaluating monitored natural attenuation programs for a variety of constituents and in a variety of environmental contexts. Dr. Heintz is a subject matter expert in microbial biodegradation and environmental molecular diagnostic tools.

Jennifer Jevnisek, Minnesota Pollution Control Agency (jennifer.jevnisek@state.mn.us)
Environmental Fate, Transport and Investigation Strategies
Jennifer Jevnisek is an Environmental Specialist for the Minnesota Pollution Control Agency's Superfund program. She is a project manager and technical analyst with 15 years of environmental project experience. Jennifer's current specializations include guidance development, high-resolution site characterization, and data visualization. She has previously acted as a contributor and section leader for ITRC's 1,4-Dioxane and Advanced Site Characterization Tools teams, and is an active member of ITRC's Environmental Data Management  team. Jennifer earned bachelor's degrees in geology and geophysics from the University of Minnesota, Twin Cities in 2006 and an undergraduate certificate in geographic information science from the University of West Florida in 2011.

Elizabeth Denly (edenly@trccompanies.com)
Elizabeth Denly is based out of Lowell, Massachusetts and is a Technical Director at TRC and the Program Director for TRC's PFAS Group. She is a chemist with 30 years of consulting experience encompassing field and laboratory analyses and audits, quality assurance/quality control, data validation, and consulting for regulatory agencies. Elizabeth is currently focusing on PFAS, specifically the nomenclature, chemistry, sampling procedures, QA/QC, and laboratory analytical methodologies, and has a significant role in educating clients, attorneys, and regulators about PFAS. She has been a leader in ITRC's PFAS Team and received the ITRC's Industry Member of the Year Award in 2017 for her work on this team. Elizabeth earned a bachelor's degree in chemistry from the University of New Hampshire in 1987 and is also a certified manager of quality/organizational excellence (CMQ/OE) by the American Society of Quality.

Charles Neslund, Eurofins (charlesneslund@eurofinsus.com)
Sampling and Analysis
Charles (Chuck) Neslund is the Scientific Officer for Eurofins Lancaster Laboratories Environmental, LLC. And PFAS Practice Leader for Eurofins Environment Testing US. Chuck has worked in environmental analytical chemistry for over 36 years and works out of the Lancaster, PA location. He is a subject matter expert in HRMS analysis and PFAS analysis. He is responsible for identifying and framing trends in analytical testing and equipment. Chuck initiates new methodology and directs research and development. He has a B.S. in Chemistry from the University of Pittsburgh (1982) and two years of graduate study credits in Organic Chemistry from the University of Pittsburgh (1982-1984). He is a member of the American Chemical Society (ACS), Chromatography Forum of Delaware Valley (CFDV), Air & Waste Management Association (AWMA), Society of Environmental Toxicology and Chemistry (SETAC), and Sediment Management Workgroup (SMWG).

Bryce Stearns, Eurofins (bryce.stearns@eurofinset.com)
Sampling and Analysis

Janet Anderson, Ph.D., DABT, GSI Environmental Inc. (jkanderson@gsi-net.com)
Toxicology and Risk Assessment
Dr. Janet Anderson is a Principal Toxicologist with GSI Environmental Inc. with 15 years of experience providing toxicology and risk management strategies to federal agencies, private industry, and municipal clients. She also provides litigation consulting and expert services and is a Diplomate of the American Board of Toxicology. Dr. Anderson specializes in communicating the key findings from toxicology studies used to inform state and federal regulatory policy and public health decisions, and helping stakeholders understand the sometimes-disparate interpretations. She is a recognized leader in unregulated and emerging chemicals, such as per- and polyfluoroalkyl substances (PFAS), 1,4-dioxane, and 1,2,3-trichloropropane. She has developed strategies to mitigate human health risks and address environmental liability associated with unregulated and emerging chemicals for both private and public sector clients. She has extensive experience developing risk communication and risk management strategies for multi-stakeholder groups. Dr. Anderson received her Ph.D. in Molecular and Cancer Biology from the University of Cincinnati, completed a post-doctoral fellowship with the U.S. Environmental Protection Agency, and as a civilian government employee, led the U.S. Air Forces Emerging Contaminants program and advised the Department of Defense on matters related to toxicology and environmental restoration. A skilled communicator, Dr. Anderson is often an invited speaker and panelist at high-level scientific conferences, regulatory and industry meetings, law seminars, technical webinars and workshops, and community stakeholder meetings.

Barrie Selcoe, Jacobs (barrie.selcoe@jacobs.com)
Toxicology and Risk Assessment
Barrie Selcoe is a Principal Technologist with Jacobs in Houston, Texas. Barrie has worked at Jacobs since 2018, specializing in human health risk assessment. She is responsible for planning and overseeing human health risk-based activities at hazardous waste sites across the U.S. and internationally. She utilizes numerous federal (USEPA and Department of Defense) and state guidance documents in risk assessment projects, and is involved in all stages of site planning, investigation and reporting, cleanup level identification, and remedial action planning. She has been involved in risk assessments in 40 states and about 20 countries. She has worked on risk assessments incorporating incremental sampling and site-specific bioaccessibility studies. She has provided risk assessment services for numerous Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)/Superfund sites, Resource Conservation and Recovery Act (RCRA) facilities, state-program sites, voluntary actions, and international projects. She has prepared risk assessments for various types of sites, including industrial and commercial facilities, industrial and municipal landfills, bulk fuel terminals, rivers, U.S. Department of Defense facilities, and residential areas. Prior to Jacobs (which purchased CH2M in 2018), she worked as a human health risk assessor for 19 years with CH2M, 7 years with Philip Environmental, and 3 years with O'Brien & Gere Engineers. Since 2012, Barrie has contributed as a team member on ITRC's Risk Assessment team, Bioavailability in Contaminated Soil team, TPH Risk Evaluation at Petroleum-Contaminated Sites team, and PFAS team. She earned a bachelor's degree in microbiology from San Diego State University in San Diego, California in 1986, and a Master's of Public Health from the University of Pittsburgh Graduate School of Public Health in Pittsburgh, Pennsylvania in 1999.

Caitlin Bell, PE, Arcadis U.S., Inc. (caitlin.bell@arcadis.com)
Remediation and Treatment Technologies
Caitlin Bell, PE is based out of Seattle, Washington and is a Technical Expert and 1,4-Dioxane Lead for Arcadis North America. She is a chemical and environmental engineer with more than a decade of experience in environmental remediation and compliance. Ms. Bell focuses on treatment of soil and groundwater using ex situ and in situ techniques. Specifically, she focuses on in situ bioremediation applications for a variety of chemicals of concern, including emerging contaminants. She serves as a technical resource on topics such as molecular biology tools, bioaugmentation, and compound specific isotope analysis. Ms. Bell was a member of the ITRC Environmental Molecular Diagnostics team and is the lead author of the 2019 Emerging Contaminants Handbook.

Ted Tyler, Cardno now Stantec (ted.tyler@cardno-gs.com)
Remediation and Treatment Technologies
Ted Tyler has 28 years of experience as a project manager and engineer providing soil, groundwater, wastewater, and air quality assessment, treatment design, permitting, construction management, and operations and maintenance services. His work has entailed sites impacted by chlorinated solvents (e.g., PCE, TCE, CT, TCA, etc.); 1,4-dioxane, PFAS, gasoline, diesel and jet fuels; perchlorate; dioxins/furans; pesticides and herbicides, metals (e.g., Cr(VI)., arsenic, etc.). He is experienced in selecting and implementing the right solution for contaminated sites including the use of physical, biological, and chemical treatment technologies, and holds a U.S. Patent for an in situ bioremediation process (No. 8,580,114). He has developed column, bench, and field pilot studies to further evaluated treatment technologies prior to implementation. Mr. Tyler is a long-term member of the Interstate Technology and Regulatory Council (ITRC) and is a frequent presenter/author regarding assessment and treatment technologies at conferences such as Battelle.

Fritz Krembs, TriHydro (fkrembs@trihydro.com)
Remediation and Treatment Technologies
Fritz Krembs, PE, PG is an environmental engineer based out of Trihydro Corporation's Golden, Colorado office. He has over 17 years of experience working in environmental remediation. He has extensive experience with in-situ chemical oxidation (ISCO), in-situ bioremediation (ISB), monitored natural attenuation, phytoremediation, and other technologies. He is Trihydro's Subject Matter Expert on 1,4-dioxane. He has led technical trainings on 1,4-dioxane, ISCO, ISB, and phytoremediation for government and private clients. He is a graduate of Colorado School of Mines and serves as a guest lecturer for their graduate level in-situ remediation course.

Moderator:

Nicole Henderson, ITRC Contractor (nicole.henderson@hmenviro.com)

Webinar Slides and References:

• 1-4DX 01252022 Final (3.65MB/PDF)

Webinar Slides and References:

• 1-4DX 01252022 Final (3.65MB/PDF)

Additional Resources:

• 1,4-Dioxane Guidance Document, (14d-1, 2021)
• 1,4- Dioxane Fact Sheets
• Risk Communication Toolkit