John Collins is the General Manager/COO of AquaBlok, Ltd. He is responsible for technology development, manufacturing, marketing and other day-to-day activities. AquaBlok developed, patented and manufactures a range of materials using their unique technology in the environmental remediation markets, as well as phosphorous reduction, annular sealants, pond/canal liners, and other geotechnical segments. Mr. Collins has over 25 years’ experience in engineering and environmental related businesses managing research, product development, technology licensing, capital goods manufacturing, and acquisitions. He has been with AquaBlok for twelve years and has guided the development of several products and managed multiple major remediation projects.
Lab and Field Assessment of Flow-Through Media for Reducing PFAS Migration in Surface and Groundwater
INTRODUCTION An Australian government owned airport services provider engaged an independent entity (Beca Consultants Pty Ltd) in a research and development program to identify methods for treating surface water from sites impacted with legacy contamination of per- and poly-fluorinated alkyl substances (PFAS). The goal was to assess the feasibility of a novel adsorption technology to mitigate the migration of PFAS via typical stormwater drainage systems at an airport and provide important data that could be utilized for the application to both surface water and groundwater. The product evaluated is composed of 4-7mm aggregate coated with a mixed powdered adsorbent that has been previously shown to adsorb PFAS in powder form. In this form, it was believed the media may be of suitable permeability to feasibly deploy in existing stormwater and groundwater systems with some modification. TESTING Two stages of investigation assessed both the physical and sorptive properties of the product at a lab scale. The goal of the first stage was to provide a preliminary proof of concept and inform the design subsequent scaled-up stages of the investigation. The second stage then involved the use of column tests to determine key parameters that would inform scale-up for field-scale. Testing involved the use of raw surface water collected from an airport site, containing a range of PFASs typical of legacy contamination from firefighting activities. The tests were performed in comparison to baseline runs using reagent water spiked with PFOS and PFOA. Data to be presented from the lab-scale trials include; adsorption isotherms, permeability, adsorption capacity, and breakthrough rates. FIELD-SCALE EVALUATION Data from testing was used to prepare a flow-through system configuration and design, as well as a data-driven spreadsheet that is intended to allow for a more rapid design process. The preliminary configurations, details of the design approach and data from field-scale evaluation of such systems will be presented. RESULTS AND DISCUSSION The lab trials were commenced in April 2019 and the second stage column trials are to be concluded in August 2019. A full data set from the lab trials will be presented. Plans are in place to proceed to field-scale evaluation at several sites. It is anticipated that data from these field-scale installations will be available for the presentation.