A soil and groundwater management plan was developed in support of a large scale infrastructure facilities upgrade project at an active air force base, 19 Wing/Canadian Forces Base Comox in Lazo, British Columbia. Impacts of per- and polyfluoroalkyl substance (PFAS) and other contaminates of concern in 37 utility sections, totaling 12 kilometers, were the primary focus of this study. Soil and groundwater management plans prioritized the reuse of soils on site and obviated the need to incur costly disposal off-island. The findings of the soil and groundwater investigations were presented in a manner which enabled ease of decision-making by on-the-ground personnel, for the efficient and cost-effective management of groundwater and relocation and reuse of suspect soils. Project design relied heavily upon the implementation of GIS-based figures during the planning stage and resulted in efficiencies during later stages of the project. The project team was able to adapt to changing project needs in response to an evolving understanding of the risks associated with PFAS-impacted media and included the addition of groundwater sampling for PFAS. Investigations were carried out within the active airfield, between runways and taxiways, firing ranges and restricted areas, and required logistical considerations of air traffic schedules and limits of approach to active runways and other controlled surfaces. Over the course of the project, several project management and project coordination strategies were applied and adapted, and a thorough understanding of the project needs and careful project planning contributed to a successful outcome. Overall, flexibility and adaptability were critical in the development of a final product that enables effective soil and groundwater handling decision-making by future construction teams.

Stephanie Kimmerle, Geologist, Dillon Consulting Limited
Stephanie Kimmerle is a professional geoscientist registered with Engineers and Geoscientists BC with five years of experience in the industry and four years with Dillon Consulting Limited. She has contributed in various roles to staged and phased environmental assessments and remediation programs for municipal, provincial and federal government clients. She has acted as coordinator for petroleum-industry remediations and long-term monitoring programs in Ontario and BC and is currently working on several large-scale geochemical and hydrogeological studies for the BC mining sector. She holds a M.Sc. in Earth and Environmental Science (McMaster University), with a focus on sedimentary geology and subsurface fluid flow and brings technical knowledge of surficial and bedrock geological systems, and hydrogeological considerations including soil properties and their influence on groundwater flow and contaminant transport.

Between September 2018 and March 2019, SNC-Lavalin Inc. was tasked to complete a detailed site investigation (DSI) to delineate previously identified hydrocarbon, polycyclic aromatic hydrocarbons (PAH), metals, and per- and polyflouroalkyl substances (PFAS) contamination in soil, sediment, groundwater, and surface water at the firefighting training area (FFTA) of Canadian Forces Base (CFB) Comox, Lazo, BC. The objective of the work was to delineate PFAS and other contaminants of concern (COC) to facilitate remediation planning and risk assessment activities.

The FFTA at CFB Comox operated from the late 1960s until circa 2009. Fire training exercises were conducted on a gravel-surfaced area surrounded by a gravel ring-road, which drained to a retention pond. Training exercises utilized aqueous film forming foam (AFFF) containing long-chain PFAS until approximately 2005. Fire training with water only has occurred until 2017. Three additional areas of environmental concern (AEC) at the FFTA included storage and use of hydrocarbons, waste oil and wastewater. Environmental investigations have been carried out at the FFTA since 2002, with PFAS first tested in samples from the FFTA in 2014. Dry summer conditions and wet saturated winter conditions observed at the FFTA increase the risk of surface water runoff and the potential for off-site migration.

In this presentation, we will review and discuss the findings of the DSI and outline the development of a conceptual site model that employed a surface drainage model developed using light detection and ranging (LiDAR) data. Project challenges and learnings will be discussed, including methodologies, precautions, and QA/QC measures particular to investigation of PFAS.

Doug McMillan, Senior Project Manager, SNC-Lavalin Inc.
Doug McMillan is a Senior Project Manager with SNC-Lavalin Inc. with over 19 years of experience in contaminated site assessment and remediation projects in Western Canada. Over the last nine years Doug has managed and executed a wide range or projects for federal and regional government clients. Doug has extensive experience working on a variety of sites including military bases, having implemented numerous projects addressing contamination in soil, groundwater, soil vapour, surface water, and sediment at upland, intertidal, and marine locations. Doug has coordinated large teams of professionals to provide integrated environmental and infrastructure services including contaminated site assessment, risk assessment, geotechnical services, terrestrial and marine biological surveys, wastewater management and air quality studies.

Various remedial technologies are emerging for per- and polyfluoroalkylated substances (PFAS). However, reviews and bench scale testing are ongoing to verify application of these remedial technologies for either total destruction or containment to reduce risks for both human health and ecological receptors. Development of site-specific remedial strategies and incorporation of new remedial technologies into remediation planning becomes increasingly difficult at active military bases. The selection of strategies and technologies for the remediation of firefighting training area (FFTA) at Canadian Forces Base (CFB) Comox considered various factors including: location of PFAS contamination and volumes of impacted soil; available space at the Base and review of offsite locations for treatment or storage of the contaminated soil; consultations with stakeholders for their requirements and operational/development plans for both short-term and long term; regulatory requirements at both the provincial and federal levels; municipal bylaws and local public needs; status of currently known remedial technologies that could be applicable for use onsite; and, review of offsite permitted facilities for disposal as an alternative. Development of a remedial plan required an optimal solution that was cost effective, met the requirements of the stakeholders and regulators in addition to reducing both the short-term and long-term liability for Canada. This presentation provides an overview of the challenges associated with developing the remedial plan for implementation at CFB Comox.

Vijay Kallur, Senior Engineer, Arcadis Canada Inc.
Vijay Kallur is a Senior Engineer with Arcadis Canada Inc. and manages multiple roles in the Pacific Region including client development, client program management, technical and business management. He holds a graduate degree in geotechnical and environmental engineering from the University of Saskatchewan, with over 29 years of multi-disciplinary experience in environmental, civil, geotechnical and construction management. He is one of the senior members of the Contaminated Sites Approved Professionals Society in British Columbia. Vijay has worked in various sectors assisting clients as an advisor for regulatory compliance and providing expertise and leadership in strategic environmental risk management for large environmental programs, spill response, infrastructure and development, industrial and high-risk sites.