© Arcadis 2016 Poly and Per Fluoroalkyl Substances (PFAS): It’s in the water, now what? Joseph Quinnan, PE, PG Arcadis June 21, 2016

© Arcadis 2016 PFAS include PFOS, PFOA and approximately 6,000 fluorinated compounds AFFF contains > 200 PFAS compounds Conventional analyses by EPA Method 537 measures 14 PFAS, only two polyflorinated What are Poly and Perfluoroalkyl Substances (PFAS)? Fluorotelemer Alcohols (FTOHs) N-alkalated Fluorooctane Sulfonamides (FOSAs) N-alkalated Fluorooctane Sulfonamidoethanols (FOSEs) + many other polyfluorinated classes

© Arcadis 2016 Detected in ~ 2% of public water supplies PFOS/PFOA in PWSs 63 water utilities with PFOS and/or PFOA detections above Health Advisory Health Advisories for long term exposure to PFOS and PFOA in drinking water (May 2016): - 70 ppt combined Previous Provisional Health Advisories for short term exposure (2009) 200 ppt PFOS 400 ppt PFOA USEPA – Unregulated contaminant monitoring rule #3,UCMR

© Arcadis 2016 Trend is lower standards – parts per trillion - Scandinavia, Germany, and US Drinking Water and Groundwater values Denmark = Σ12 PFAS = µg/L, includes PFBS, PFHxS, PFOS, PFOSA, 6:2 FTS, PFB, PFPeA, PFHxA, PFHp, PFOA, PFNA, PFDA Sweden = Σ7 PFAS = µg/L, includes PFBS, PFHxS, PFOS, PFPeA, PFHxA, PFHpA, PFOA US = Σ2 PFAS = µg/L, includes PFOS, PFOA Drinking Water Criteria in µg/l in European Countries PFOSPFOAPFOSAPFBSPFBAPFPeAPFHxAPFHpAPFNAPFDA6:2 FTSPFHpSPFHxSPFPeS Denmark 1 (0.1) - - Germany The Netherlands Sweden 2 (0.09) - - (0.09)-----(0.09)- U.K Drinking Water Criteria in µg/l U.S. PFOSPFOAPFOSAPFBSPFBAPFPeAPFHxAPFHpAPFNAPFDA6:2 FTSPFHpSPFHxSPFPeS Minnesota New Jersey Vermont 0.02 U.S. EPA 3 (0.07) Canada Groundwater Criteria in µg/l in European Countries PFOSPFOAPFOSAPFBSPFBAPFPeAPFHxAPFHpAPFNAPFDA6:2 FTSPFHpSPFHxSPFPeS Denmark(0.1) - - Germany State of Bavaria State of Baden Württemberg The Netherlands Groundwater Criteria in µg/l in U.S. PFOSPFOAPFOSAPFBSPFBAPFPeAPFHxAPFHpAPFNAPFDA6:2 FTSPFHpSPFHxSPFPeS New Jersey Texas, Residential

© Arcadis 2016 PFOS AA-EQS is extremely low - parts per quadrillion Very conservative - 3 orders of magnitude lower than drinking water standards. EU Surface Water Quality Standards Directive on “Environmental Quality Standards” EQSD 2008/105/EC, daughter directive of the Water Framework Directive: Standards for priority hazardous substances. Review each 6 years. In 2013, PFOS was added as a priority hazardous substance / EQS derived by RIVM (NL). Member State Legislation: November The EQS shall be met by End of Name of substance Annual Average-EQS (µg/L) Max. Allowable Con. EQS (µg/L) EQS (µg/kg) Inland surface waters Other surface waters Inland surface waters Other surface waters Biota Perfluoro octane sulfonic acid and its derivatives (PFOS)

© Arcadis 2016 PFAS Water Treatment Dickenson and Higgins, Treatment mitigation strategies for poly- and perfluoralkyl substances, Water Research Foundation Conventional Treatment Specialized Treatment Conventional Oxidation

© Arcadis 2016 PFAS Water Treatment Conventional waste/water treatment methods at POTWs not effective for PFOS/PFOA Most common approach is Granular Activated Carbon (GAC) o Effective in removing PFOS/PFOA, however sorption is low and competition occurs (higher costs than conventional contaminants) o Increasingly less effective as PFAS chain length diminishes o Thermal incineration/regeneration is costly Ion exchange resins or polymers effective for PFOS/PFOA; less effective for shorter-chain PFAS Can be regenerated; thermal incineration of concentrated backwash Nano filtration and reverse osmosis – broad-spectrum capability, effective for shorter-chained PFAS Treatment of backwash, membrane and/or RO concentrates required Conventional Oxidation is difficult due to strength of the C-F bond and may lead to higher PFCA / PFSA levels as a result of precursor breakdown

© Arcadis RSSCTs determine GAC needs to treat PFAS -GAC requirements are site specific -PFAS mixtures -Competition from -TOC from groundwater or surface water -Other contaminants GAC - Isotherm Testing Rapid small scale column tests (RSSCTs) Example results show approximately 0.1 lbs GAC/1000 gallons of groundwater

© Arcadis 2016 Aerobic Biotransformation of Precursors Approximately 25 PFAAs – PFSAs and PFCAs Hundreds of common intermediate transformation products All polyfluorinated / PFAA precursor compounds in commerce “Dark Matter” Need for analytical methods to characterize mixtures with precursors Determine water treatment requirements Understand source behavior and restoration requirements

© Arcadis 2016 TOP Assay Total oxidizable precursors TOP Assay converts PFAA precursors to PFAA compounds Oxidation mimics decades of aerobic transformation in a few minutes. The difference in PFAA mass, determined by measuring PFAAs before and after TOP assay by EPA Method 537 corresponds to the total PFAA precursor concentration Houtz, Erika, and David L. Sedlak Oxidative conversion as a means of detecting precursors to perfluoroalkyl acids in urban runoff. Environmental Science and Technology 46:

© Arcadis 2016 Fire Training Area - Conceptual Site Model