section header EN

Halifax Convention Centre, 1650 Argyle Street, Halifax, NS
June 4-5, 2019 


The “Outside-In” Approach: A New Paradigm for PFAS Site Investigation, Risk Assessment and Risk Management
Jody Berry, Tony Rodolakis, Amy Quintin
Wood
The objective of this presentation is to provide evidence that this “outside-in” risk-based approach is better suited for managing PFAS than the traditional remedial investigation/feasibility study framework.
Abstract

Background/Objectives: As a result of their widespread presence in aqueous film-forming foam (AFFF), per- and polyfluoroalkyl substances (PFAS) have entered the food chain and contaminated vast groundwater areas. PFAS are suspected to cause cancer and tumours, weaken the immune system, and affect fetal development. Yet even with the paucity of regulatory drivers there is clearly a need to investigate and remediate PFAS to protect human health and the environment, as well as to avoid future litigation costs and damage to public relations. The traditional remedial investigation/feasibility study (RI/FS) approach is to identify the source, delineate nature and extent, and then characterize risk to off-site receptors, a deliberate and prodding process. Heightened public concern and social pressure, physical and chemical characteristics that make PFAS highly mobile, and a poor understanding of fate have forced a new paradigm wherein risks are identified, and complete off-site exposure pathways are evaluated even before sources are fully characterized, i.e., an “outside-in approach.” This presentation provides evidence that the “outside-in” risk-based approach is better suited for managing PFAS than the traditional RI/FS framework.

Approach/Activities: At several sites, including in the USA and Australia, parties have taken an “outside-in” approach whereby potentially affected areas are screened for at-risk receptors, sampled, and assessed for risk. Then, the intermediate portions of the conceptual site model (CSM), such as sources, transport mechanisms, and complete exposure pathways are filled in. This approach helps to rapidly communicate risks to human health and the environment (or lack thereof) to regulators and members of the general public.

“Outside-in” Human Health Risk Assessments have used a combination of health-based standards and guidelines and site-specific concentrations of dietary items (e.g., eggs, fish, vegetables) to calculate potential risks from PFOS, PFOA, and PFHxS.

“Outside-in” Ecological Risk Assessments have relied on a patchwork of scarce but growing body of screening benchmarks protective of direct contact and food chain exposures, supplemented with site-specific tissue testing to develop BCF, BAFs, BSAFs, and BMFs to refine risk estimates.

Two case studies are presented where the “outside-in” approach was used to illustrate the benefits and risks relative to the traditional RI/FS framework. Factors evaluated include stakeholder expectations/results, schedule, costs, regulatory impact, management of uncertainties, and risks to the client.

Results/Lessons Learned: Using the “outside-in” approach, we have been able to rapidly demonstrate where there are negligible risks to human and ecological health from PFAS and identify priority areas for immediate risk management, allowing the client to rapidly satisfy public concerns and focus future efforts on source control.

Jody Berry, Senior Environmental Engineer, Wood
As Senior Environmental Engineer at Wood, Jody Berry acts as a technical specialist on sediment investigations and ecological risk assessment for various federal agencies such as Fisheries and Oceans Canada, the Department of National Defence and Transport Canada. Jody is the senior technical reviewer for PFAS investigations in terrestrial, marine, freshwater environments. He is an experienced contaminated sites risk assessor who specializes in assessing potential impacts to people, wildlife, and aquatic life and has conducted risk assessments for hundreds of Sites in Canada, Australia, and the USA. Jody has liaised with municipal, provincial and federal government agencies such as the Ministry of Environment, Health Canada and Fisheries and Oceans Canada.

Tony Rodolakis, Wood Environment & Infrastructure Solutions, Inc.
Mr. Rodolakis has 25 years of experience directing, managing and executing ecological risk assessments and other environmental quality projects.  He has performed risk assessments and impact studies following national USEPA, Environment Canada, and other internationally recognized programs across North America, South America, Australia, and the Caribbean under FCSAP, CERCLA, in under 25 US state and 8 Canadian provincial programs.  Project sites include military, , manufacturing, mining, port, and transportation infrastructure sites.  Mr. Rodolakis applies site-specific weight of evidence approaches to ecological risk assessment based on state-of-the art science to help clients eliminate negligible exposure pathways and chemicals from costly investigation, and to reduce mitigation efforts by developing risk-based clean-up goals.  Mr. Rodolakis is also happy to see the Bruins back in the Stanley Cup Finals.

 

A Programmatic Approach to Protecting Human Health and Environment from PFAS
Melissa HeltonWood
The objective of the presentation is to discuss and highlight Wood’s involvement in key protocols, tools, systems, and strategy. Challenges with identifying requirements that align with current policy and regulations were overcome in order to implement timely execution of projects and timely mitigation of exposures and risk to human health and the environment
Abstract

Background/Objectives: The US Air Force (USAF) has established a PFAS Program to address releases of per- and polyfluoroalkyl substances (PFAS) resulting from its use of aqueous film-forming foam (AFFF). Through this program, the Air Force has initiated numerous measures and response actions which include the issuance of policy memorandums and guidance, revamping its fire training facilities, revising training protocols, initiating the replacement of C8-based AFFF, executing preliminary assessments and/or site inspections (PA/SI’s) to evaluate if there is a threat to human health and the environment, conducting and sponsoring research in analytical techniques, risk assessment, and treatment technologies; and implementing mitigation measures to minimize drinking water exposures. This presentation will cover how the Air Force evaluated PFAS across the United States using a proactive and programmatic project approach focusing on four primary facets of project management: conception/initiation; definition and planning; project launch and execution; and, performance and control. Each facet was uniquely approached to accommodate the ever-changing and dynamic social, scientific and regulatory status of this emerging contaminant class. In addition, the results and lessons learned from the process will be shared.

Approach/Activities: The USAF approach follows an emerging contaminant protocol coined “Identify, Respond, and Prevent” to address PFOS/PFOA contamination at all USAF installations (Active, Reserve, Air National Guard, and Base Realignment and Closure (BRAC) program). A criterion for mitigation activities in accordance with USAF policy referred to as the “3Ps” (probability, proximity, and pathway) is employed after confirmation of PFOS/PFOA above lifetime health advisory. The USAF continually re-evaluates prioritizations based on regulatory changes and stakeholder concerns using a tiered approach for contamination found in receptor drinking water and groundwater. A critical component to the success of the USAF program is a communication strategy with all stakeholders (Department of Defense (DoD), federal/state representatives, regulatory agencies, communities, contractors). This includes development of a PFOS/PFOA webpage, Public Affairs guidance and toolkit, media engagement, and community engagements/public meetings.

To identify technology solutions to PFOS/PFOA clean-up issued, the US DoD has shifted investments to focus on emerging contaminants. Research is being funded through the Strategic Environmental Research and Development Program (SERDP) and Environmental Security Technology Certification Program (ESTCP). An update on the research activities will be discussed.

Melissa Helton, Associate Project Manager, Wood Melissa Helton is an Associate Project Manager for Wood located in the Knoxville, TN office. Melissa has more than 20 years of environmental investigation and remediation experience and has extensive experience in project management for federal and private sector programs. She is the Program Manager for multiple task orders specifically awarded to address where AFFF was used or stored and PFAS were released into surface water, sediment, soil, groundwater, and drinking water. Task order activities include conducting site inspections, delineation, remedial design, wellhead treatment, and installation and operation of residential and municipal treatment systems at 22 BRAC Air Force bases and 30 active Air Force bases across the US.

Site Management Challenges – When Emerging Contaminants Reverse Your Site Closure Plans
Suzanne O’Hara, David Reynolds, Leah MacKinnon
Geosyntec Consultants International, Inc.
The objective of this presentation is to review case studies for sites where PFAS has significantly changed a site closure plan or reversed the closure designation, relate this to some of the guidance for site closure reversals base on the vapour intrusion pathway and how it relates to Canadian Federal Contaminated Sites.
Abstract

It has been said, “The only places we’re not finding PFAS are places we’re not looking” (Heidi Grether, Director, Michigan Department of Environmental Quality).

The widespread presence of per- and polyfluoroalkyl substances (PFAS) in the environment and its many possible sources make for complicated conceptual site models and difficulty in distinguishing sources of the impacts. The majority of PFAS constituents cannot be detected using commercially available analytical techniques. Progress is being made towards developing analytical techniques to improve the detection of these constituents, including recent research by the authors and academic and industry partners developing nuclear magnetic resonance (NMR)-based analytical techniques and total fluoride field screening, but it may be years before comprehensive site characterisation is achievable. However, the widespread detections of some PFAS in humans and wildlife and mounting evidence that PFAS bioaccumulate have raised concerns regarding human health and ecological risks and put pressure on the regulators to develop environmental criteria while the scientific understanding of the risks and behaviours of these compounds is still developing.

With the prevalence of PFAS detections, the current drinking water health advisory limits being set in Canada and abroad, and the anticipated future regulatory levels, there are many sites whose current remedial action plan or site closure plan will need to be re-evaluated to consider PFAS. Similar to the vapour intrusion (VI) pathway for volatile organic compounds (VOC) sites, which was often excluded from a site’s investigation and remedial process, many sites which may have achieved closure will need to be/are being re-evaluated with respect to PFAS risks.

Thousands of closed sites in the United States have been or are being re-evaluated, and reopened if necessary, in terms of the VI pathway. Ranking criteria are applied to site re-evaluations which were chosen based on site conditions that are believed to play a significant role in the VI pathway. Similar re-evaluations are expected or ongoing for potential risks from PFAS at sites which have achieved closure or are well on their way through their site closure path. PFAS detections will result in major upheavals and potential reversals of approved in situ site remedies that may not be capable of treating PFAS. The US Department of the Navy for example, has issued site guidance for their remedial project managers which includes the recommendation to consider sampling for PFAS at closed sites if the conceptual site model strongly suggests PFAS have impacted media and supports current or potential future exposure. The behaviour of the PFAS constituents in the environment can vary widely depending on the composition of the PFAS mixture, the presence of co-contaminants, etc. It is essential that knowledgeable practitioners, who fundamentally understand the limitations and challenges associated with PFAS, direct investigation and remediation efforts to achieve successful mitigation of risk at PFAS sites.

This presentation will review case studies for sites where PFAS has significantly changed a site closure plan or reversed the closure designation, relate this to some of the guidance for site closure reversals based on the VI pathway and how it relates to Canadian federal contaminated sites.

Suzanne O’Hara, Senior Hydrogeologist, Geosyntec Consultants International, Inc.
Suzanne O’Hara is a hydrogeologist with more than 20 years experience. She uses her experience to support clients through her focus on conceptual site model (CSM) development and remediation of groundwater and soil using innovative and more conventional technologies.

Her remediation expertise includes enhanced in situ bioremediation, in situ chemical oxidization and reduction, self-sustaining treatment for active remediation (STAR) thermal remediation, passive treatment using zero valent metals, and the treatment of PCBs in building materials.

Suzanne has directed, managed, or provided technical support for projects ranging from overall strategy development, site investigation, long term monitoring, monitoring and remedial design, costing and implementation, contaminant fate and transport, and CSM development.

Questions en

fb icon   Twitter icon   linkedIn icon