SAFF® Applications: Groundwater
SAFF® Applications: Groundwater
Since commissioning in April 2019, this SAFF unit has successfully remediated more than 100M litres (26.42M gallons), with an average concentration factor of between 1.5M to 2M times.
The groundwater solution
SAFF units have proven their ability to effectively remediate target PFAS contaminants to below detection levels at several groundwater sites. SAFF’s first commissioned project involved remediation of groundwater at a Defence site within Australia. This significant project has moved from pilot to long-term rolling contract and has become a critical source for our technology validation.
Since commissioning in April 2019, this SAFF unit has successfully remediated more than 100M litres (26.42M gallons), with no exceedances of criteria PFAS compounds, and produced 71L (18.75 gallons) of PFAS hyper concentrate ready for permanent destruction. This represents an average concentration factor of between 1.5M to 2M times.
This result has been achieved without use of ion exchange resin or GAC, instead utilising the naturally elegant SAFF process which relies on the gas water interface of a rising air bubble to provide an essentially infinite surface area for PFAS compounds to absorb to. These molecules, once bound to the air bubble, rise to the surface where they are harvested, ready for concentration and further dewatering
Why is management of PFAS in groundwater important?
There are a number of ways for PFAS impacted compounds to enter groundwater. Sources could be AFFF run off from an airport or Defence training site, industrial effluent, leachate from landfills, or discharge from a manufacturing facility which uses PFAS.
Once present in groundwater, these silent and invisible PFAS molecules become mobile over time. As plumes migrate off site and away from the point of pollution, they can potentially impact adjacent aquifers, boreholes, creeks and river systems.
Different PFAS molecules move at different rates, and the signature of a PFAS plume changes the further it is away from the source. Short chain PFAS molecules tend to migrate faster; while long chain PFAS molecules tend to remain closer to the source of the contamination. This influences the positioning of remediation techniques, with long chains typically a higher priority for remediators to recover due to their known health impacts.
SAFF® Predictability Model
Try our free SAFF® Predictability Model.
Simply input your data to predict the percentage of PFAS removal for your water chemistry.
How it Works
SAFF’s unique ability to utilise air bubbles as the PFAS adsorption medium means that the SAFF technology can achieve extremely high concentration factors and very efficient PFAS removal for a fraction of the cost of competitor technologies. Further, the ability of the technology to create miniscule waste streams means that waste disposal costs are also significantly reduced.
EPOC Enviro works with clients to locate and develop an extraction array of groundwater wells which are manifolded to a single ground water supply line to deliver water directly to the SAFF unit. The well array is positioned down gradient of the source zone in a manner which optimises the removal of sub-surface PFAS impacted groundwater.
Using no other pre-treatment other than basic bag filters to remove coarse materials, the groundwater is pumped through the SAFF system, where the PFAS is removed and concentrated into a tiny volume of hyper concentrate ready for destruction by third party destruction technology providers.
Treatment volumes using a SAFF system on groundwater would typically be in excess of 400,000L (105,820 gallons) per day and may be as high as 800,000L (211,640 gallons) per day, or 147 gallons per minute, depending on the background PFAS signature and prevailing lithology at the site.
The SAFF technology is unique in that the flow rate to the plant can vary from zero gallons per day up to the maximum, with no detriment to overall PFAS removal performance. Similarly, the PFAS concentration can vary from single digit PPT levels up to tens of thousands of PPB with minimal variation in treatment throughput, cost or efficiency.
SAFF’s unique ability to utilise air bubbles as the PFAS adsorption medium means that the SAFF technology can achieve extremely high concentration factors and very efficient PFAS removal for a fraction of the cost of competitor technologies. Further, the ability of the technology to create miniscule waste streams means that waste disposal costs are also significantly reduced.
The overall treatment process is a reliable, energy efficient, and low-cost technology with a proven capacity for the long-term removal of PFAS from groundwater sources.
SAFF40 Primary Fractionation/Stripping Results, Oct 2019 – Oct 2021
Army Aviation Centre Oakey (AACO) Groundwater (QLD, Australia)
Predictability Model (1)
Bench Scale Testing(1.4)
Percentage(4)
Table-1 Footnotes
(1) Predictability modelling means a review of historical lab reports. Bench scale testing means experiments using lab apparatus and site water.
(2) Approx. 30,000m3 feedwater treated, refer to site details.
(3) Australian & New Zealand Heads of EPA (HEPA) NEMP (2020) PFAS drinking water criteria adopted as site criteria for treatment purposes.
(4) Removal percentage (%R) is calculated by comparing treatment results to feed and trace lab LOR (1.o ng/l), 6:2-FTS (5.0 ng/l).
(5) Adsorption coefficient PFAS species in de-ionised water-air interface at pH7, Brusseau (2019).
Contact Us
Learn how EPOC Enviro can help your PFAS Remediation needs!