the emerging issue per- polyfluoroalkyl substances … · • fluorotelomer sulfonic acids (ftss)...

APRIL 2020 NEXT

IAN ROSS, Ph.D. ARCADIS UKGLOBAL PFAS LEAD

PER- & POLYFLUOROALKYL SUBSTANCES (PFASs) Big Picture, Challenges and Solutions

THE EMERGING ISSUE

© Arcadis 2016

Safety Moment: Foam “Disposal”

2

© Arcadis 2016 3

Property of Arcadis, all rights reserved

• PFAS News

• PFAS Chemistry, Characteristics and Analysis

• Widespread Uses

• Regulatory trends

• Firefighting Foams -Transition

• PFAS Behaviour - Fate and Transport

• Long Range Transport - Background

• PFAS point source risk management via CSMs

• Evolving treatment / Remediation strategies

• Summary

Overview

A CHANGING WORLD

In the News

2014-2018

© Arcadis 2016Detections of PFAS in drinking water has caused spiraling regulatory concern

PFAS News

© Arcadis 2016

August 14, 2020 6

Detected in ~ 2% of large public water supplies

USEPA UMCR 3, May 2016

PFASs in US Public Water Supplies

© Arcadis 2016

http://www.nytimes.com/2016/01/10/magazine/the-lawyer-who-

became-duponts-worst-nightmare.html?_r=0

http://www.nytimes.com/2016/01/10/magazine/the-lawyer-who-became-duponts-worst-nightmare.html?_r=0

© Arcadis 2016 8/14/2020 8

PFAS management requires pragmatism..

https://www.dutchnews.nl/news/2019/10/builders-pollution-protest-breaks-up-after-diggers-dump-earth-on-the-malieveld/

https://nltimes.nl/2019/10/30/construction-vehicles-heading-hague-protest-traffic-piling

https://www.dutchnews.nl/news/2019/10/ministers-aim-to-relax-pfas-

pollution-rules-after-new-limit-halts-earth-moving-work/

https://www.dutchnews.nl/news/2019/10/builders-pollution-protest-breaks-up-after-diggers-dump-earth-on-the-malieveld/

https://nltimes.nl/2019/10/30/construction-vehicles-heading-hague-protest-traffic-piling

https://www.dutchnews.nl/news/2019/10/ministers-aim-to-relax-pfas-pollution-rules-after-new-limit-halts-earth-moving-work/

PFASs PROPERTIES AND CHEMISTRY

© Arcadis 2016

Specific Characteristics of PFASs

• MobilityPFASs tend to be very mobile in the environment as they are soluble in water (unlike most other POPs).

• Extreme PersistencePFASs show no sign of biodegradation and have been termed “forever chemicals”

• SurfactantsAmphiphilic PFASs stick on surfaces / interfaces when at higher concentrations

• BioaccumulationPFASs bioaccumulate and biomagnify via interaction with proteins (not fats like other POPs)Long Chain PFASs concentrate humans via renal reabsorption, so we fail to excrete them, whilst monkeys, mice and rats etc. can excrete at much faster rates

• ToxicityThere are very low (~70 ng/L) and diminishing regulatory acceptance criteria (drinking water standards) as more is known about the toxicity of specific PFASs

August 14, 2020 10


© Arcadis 2016 August 14, 2020 11

PFAAs totally resist biodegradation – are ultra-persistent

• Perfluoroalkyl acids (PFAAs) previously termed

Perfluorinated Compounds (PFCs) generally are

the and include:

• Perfluoralkyl carboxylates (PFCAs) e.g. PFOA

• Perfluoroalkyl sulfonates (PFSAs) e.g. PFOS

• Perfluoroalkyl phosphinic acids (PFPiS);

perfluoroalkyl phosphonic acids (PFPAs)

• Perfluoroalkyl ethers e.g. GenX

• There are many PFAAs with differing chain

lengths (generally C1-C18)

Perfluoroalkyl Acids (PFAAs)


© Arcadis 2016

Polyfluorinated Compounds -Precursors

• Thousands of polyfluorinated precursors to PFAAs have been commercially synthesized for bulk products

• The common feature of the precursors is that they will biotransform to make PFAA’s as persistent “dead end” daughter products

• PFAS do not biodegrade i.e. mineralise

• Some precursors are fluorotelomers

• Some are cationic (positively charged) or zwitterionic (mixed charges) –this influences their fate and transport in the environment

• Cationic / zwitterionic PFAS tend to be less mobile than anionic PFAAs and so can potentially be retained longer in “source zones”

• Environmental fate and transport will be complex as PFAS comprise multiple chain lengths and charges

PFOA


© Arcadis 2016

Poly- and Perfluoroalkyl Substances (PFASs) (~5,000 manufactured compounds)

Perfluorinated Compounds(PFCs)

or Perfluoroalkyl Acids (PFAAs)

~25 common individual compounds, terminal

daughters i.e. “forever chemicals”

e.g. PFOS, PFOA, PFHxS, PFBA, PFHxA

Polyfluorinated

“Precursors” -Proprietary

PFASs

Thousands of individual parent

compounds, sharing common

daughters e.g. 6:2 FTS, 5:3 acid

Environmental / Higher Organism Biotransformation

More Commonly Regulated


© Arcadis 2016

Perfluoroalkyl group –confers extreme persistence

PFOA

PFOS

PFHxS


© Arcadis 2016

Aerobic Biotransformation Funnel: Conversion of Polyfluorinated Precursors to PFAAs

August 14, 2020 15

ANALYTICAL TOOLS

© Arcadis 2016

Analysis by LCMSMS via EPA Method 537 or similar

Conventional analysis will not reflect total PFAS mass

• US EPA Method 537: Analysis for selected PFAS in drinking water

• 12 PFAAs and 2 Precursors:

– PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUA, PFDoA, PFTrA, PFTeA

– PFBS, PFHxS, PFOS

– N-EtFOSAA, N-MeFOSAA

• EPA 24

– PFTeDA, PFTrDA, PFDoA, PFUdA, PFDA, PFNA, PFOA, PFHpA, PFHxA, PFPeA, PFBA

– PFDS, PFNS, PFOS, PFHpS, PFHxSK, PFPeS, PFBS

– FOSA, 8:2FTS, 6:2FTS, 4:2FTS, N-EtFOSAA, N-MeFOSAA

• Method 537 has been adapted with more analytes to other media

• Up to 65 individual analytes (laboratory dependent)

• Groundwater with PFAS LODs ranging as low as 0.09 ng/L

• Availability of standards and other factors limit the number of PFAS that can be measured with a single method

• Thousands of precursors and their transient metabolites makes synthesis of a comprehensive set of standards unrealistic


© Arcadis 2016

Other PFAS Analytical Methods

MethodDemonstrated

Matrices

PFAS

Specific?

Total Oxidizable Precursor (TOP)

Assay

Aqueous, Soil, Human

Blood, Commercial

products

Yes

Extractable Organofluorine and

Ion Chromatography

Aqueous, Human

BloodNo

Particle Induced Gamma

Emission (PIGE) SpectroscopyCommercial products No

High Resolution Mass

SpectrometryAqueous, Solids Yes*

1806 February 2020

Total Organofluorine

Methods

© Arcadis 2016

Digest AFFF precursors and measure the hidden mass: TOP Assay

Microbes slowly make simpler PFAA’s (e.g. PFOS / PFOA) from PFAS (PFAA precursors) over 20+ years

Need to determine precursor concentrations as they will form PFAAs

Too many PFAS compounds and precursors –so very expensive analysis

Oxidative digest stoichiometrically converts PFAA precursors to PFAA’s

TOP assay indirectly measures total precursors as a result of increased PFAAs formed after oxidation vs before.


Analytical tools fail to measure the hidden PFAS precursor mass, the TOP assay solves this

© Arcadis 2016

0

5

10

15

20

ECF,2001

FT 1,2005

FT 2,2002

FT 3,2009

FT 4,2003

Co

nce

ntr

atio

n, g

/L

Pre-TOP Assay

PFOS

PFHpS

PFHxS

PFBS

PFNA

PFOA

PFHpA

PFHxA

PFPA

PFBA

Many formulations appear PFAS-free until precursors are revealed by TOP Assay

0

5

10

15

20

ECF,2001

FT 1,2005

FT 2,2002

FT 3,2009

FT 4,2003

Co

nce

ntr

atio

n, g

/L

Post-TOP Assay

PFOS

PFHpS

PFHxS

PFBS

PFNA

PFOA

PFHpA

PFHxA

PFPA

PFBA

FT: Fluorotelomer

ECF = Electrochemical Fluorination


TOP Assay Applied to AFFF Formulations

FT: Fluorotelomer

ECF = Electrochemical Fluorination

Houtz et al., 2013

PFASs Manufacturing and UsesWhere We Find Them and How They’ve Evolved


Firefighting Foams

Metal Plating

Textiles Electronics Photography Paper Coatings Paints Hydraulic Fluids

© Arcadis 2016

Manufacture of PFASs Three main methods of manufacture:

1. Electrochemical Fluorination

Used to manufacture branched and straight chain (~30% / 70%):

• perfluorosulfonates (e.g. PFOS, PFBS) and perfluorocarboxylates (e.g. PFOA)

• perfluoroalkylsulfonamides (e.g. FASAs, FASEs, FOSAAs, SAmPAP,

diSAmPAP, PFASaAm, PFASaAm)

2. Fluorotelomerisation

Used to manufacture even carbon numbered PFCA or PFPA/PFPiA precursors such as:

• Fluorotelomer alcohols (FTOHs) e.g. 6:2 FTOH,

• Fluorotelomer sulfonic acids (FTSs) e.g. 6:2 FTS, 8:2 FTS

• Fluorotelomer carboxylic acids (FTCAs) Fluorotelomer betaines (FTBs),

• Polyfluoroalkyl phosphates (PAPs) such as the diPAPs etc. etc.

3. Oligomerisation

Used to manufacture perfluoroalkylethers (PFECAs) and perfluoroalkyl ether sulfonate (PFESAs) such as: GenX hexafluoropropylene oxide dimer acid (HFPO-DA), HFPO-TA, ADONA

2206 February 2020

sulfonamido ethanol-based phosphate triester (tri-SAmPAP)

© Arcadis 2016

• Fluorosurfactant Firefighting foams for Class B (liquid hydrocarbon) fires e.g. Aqueous Film Forming Foams (AFFF), Film Forming Fluoroprotein Foams (FFFP)

• Electroplating mist suppressants

• Semiconductor manufacture

• Pesticides –Insecticides and Herbicides

• Aviation Hydraulic fluids

• Consumer Products

• Oil and water resistant finishes (paper, textiles, carpeting, cookware); Fast-food packagine

• Dyes, Polishes, Adhesives, Lubricants, Inks, Waxes

• Cleaning agents –detergents, carpet cleaners

• Shampoos and Hand creams

Multiple and Varied PFAS Uses


© Arcadis 2016

Potential Locations of PFAS Point Source Contamination

• Primary Manufacturing

• Secondary manufacturing / uses via application of PFASs to other products e.g.

o Fluoroplastics (e.g. PTFE)

o Paper Mills

o Carpet and Textile Manufacturing

o Metal Plating

o Paint Manufacturing

o Car wash/wax

o Leather tanneries

• Fire Training Sites

o Airports, Civil, Defence, Oil & Gas sites, Rail Yards, Power Plants

• Wastewater treatment plants –biosolid disposal

• Landfills


© Arcadis 2016

Next Generation PFASs

TOXICOLOGY / REGULATORY CLIMATE / PFAS DISTRIBUTION

Evolution of regulatory understanding globally and global distribution


© Arcadis 2016

Drinking Water

And Food

House dust

Indoor air

Outdoor air

Consumer products

• Fluoropolymers incl. side chain polymers

• Fluorosurfactants

• Performance chemicals

• Product residualsPrecursor

PFAA


Human Exposure to PFASs / Toxicity Long Chain Human

Bioaccumulation Half Life:

PFHxS 8.5 years

PFOS 4.2 years

PFOA 3.8 years

• PFAS bind to proteins (not to lipids / fats)

and are mainly detected in blood, liver and

kidneys

• PFOS: carcinogenity “suggestive” (US EPA,

2014). PFOA: “possibly carcinogenic”

(International Agency for Research on

Cancer, IARC, 2014)

• Study with 656 children demonstrated

elevated exposure to PFOS & PFOA are

associated with reduced humoral immune

response [1]

• Large epidemiological study of 69,000

persons found probable link between

elevated PFOA blood levels and the

following diseases: high cholesterol,

ulcerative colitis, thyroid disease, testicular

cancer, kidney cancer and preeclampsia –

C8 science panel [2]

[2] http://www.c8sciencepanel.org/

[1] Grandjean et al., JAMA 2012, 307, 391-397

© Arcadis 2016

0

200

400

600

800

1,000

1,200

1,400

1,600

EFSA,2008

EPA, 2009 2010 to2014

Denmark,2015

EPA, 2016(RfD)

RIVM,2016

Australia,2017

2018

TDI (ng/kg/body weight/d)

PFOS

PFOA

Source TDI PFOS

(ng/kg bw/day

TDI PFOA

(ng/kg bw/day)

EFSA, 2008 150 1500

EPA, 2009 80 190

Denmark, 2015 30 100

EPA, 2016 (RfD) 20 20

RIVM, 2016 - 12.5

Australia, 2017 20 160

EFSA, 2018 1.8 0.8

Tolerable Daily Intake (TDI)


© Arcadis 2016

Evolving Global Regulatory PFAS Values

29

Drinking, Surface and Ground Water (µg/l)

PFOS O=8

PFOA O=8

PFBS B=4

PFBA B=4

PFPeA/S Pe=5

PFHxA Hx=6

DENMARK(Drinking & Groundwater)

FEDERALGERMANY

(Drinking Water)

UK(Drinking Water)

AUSTRALIA(Drinking Water)

(0.09)

THE NETHERLANDS

US EPA(Drinking Water)

VERMONT(Drinking Water)

MINNESOTA(Drinking Water)

NEW JERSEY

CANADA(Drinking Water)

PFHxS Hx=6

PFHpA Hp=7

PFOSA O=8

PFNA N=9

PFDA D=10

Gen-X C6

COMPOUND REGULATED AND CHAIN LENGTH KEY

(0.07)

ITALY(Drinking Water)

(0.07)

TEXAS-Residential(Groundwater)

0.56

(1)

0.10.06

0.1

6

10

6

.030.5

0.5

(0.1)

1

0.60.2

15

30

0.20.2

0.2

0.02

.014.013

(0.02)

0.015.035

7

3

0.56

0.29

34

71

.093.093

0.56

0.290.37

.093

0.6

.53

.023ground

drinking

0.5

drinking

drinking.01ground

0.29

SWEDEN(Drinking Water)

(0.5)(0.5)

(0.5)(0.5)

(0.5)(0.5)

5

STATE OF BADEN-WÜRTTEMBERG

(Groundwater)

0.1

European Surface Waters (PFOS) 0.00065

Australian Surface Waters (PFOS) 0.00023

(0.07)

.013

MICHIGAN(Drinking Water)

(0.07).014

CONNECTICUT(Drinking Water)

(0.07)

ALASKA(Drinking Water)

(0.07)

NEW YORK(Drinking Water)

MICHIGAN(Groundwater

Surface Water Interface0.012 PFOS

0.01

0.01

CALIFORNIA(Drinking Water)

.014

0.0510.065


0.047

0.14

NORTHCAROLINAdrinking

0.10.1

“Race to the Bottom”

Queensland 0.25

(PFASs TOP Assay)

© Arcadis 2016

POPs Listed under Stockholm Convention

Original 12 are referred to as the Dirty Dozen:

• Aldrin, chlordane, DDT (some acceptable uses exempted), dieldrin, endrin, heptachlor, hexachlorobenzene, mirex, toxaphene, polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/PCDF)

Annex A: Listed for elimination (22 chemicals)

Annex B: Restricted (2 chemicals, DDT & PFOS)

Annex C: Avoid unintentional release (6 chemicals)

PFHxS and PFOA under consideration for classification

August 14, 2020 31

© Arcadis 2016

Persistent Organic Pollutants

If chemical are “PBT”, they can be restricted under European REACH and Stockholm Convention:

• Persistent:

• Half lives > 40 days in freshwater, >120 days in soil (REACH)

• Bioaccumulative:

• Bioconcentration factor/bioaccumulation factor in fish >2000 (REACH)

• Toxic

• Human: Chronic toxicity, carcinogenic/mutagenic/reprotoxic

• Ecological: No effect concentration (NOEC) <0.01 mg/L

August 14, 2020 32

PCBs

DDT

PFOS

© Arcadis 2016

Long Chain PFAS Replacements

Replacement shorter chain PFASs pose potential larger environmental threat

• Fluorotelomers are not biodegradable they form persistent PFAAs

• Concerns regarding Fluorotelomer precursors and (C6) replacements

• Multiple intermediate PFASs (~30 PFASs) evolved as fluorotelomersbiotransform

• Evidence of bioaccumulation of intermediates in rats (5:3 acid), invertebrates (6:2 FTS) and short chain PFAA bioaccumulation in edible portion of crops

• Fluorotelomer precursors described as being 10,000 X more toxic than PFAAs they biotransform into

• Limited information regarding toxicology of intermediates and PFAAs formed

• Short chain PFAAs, very water soluble, highly mobile, difficult to remove from wastewater, recirculate around water bodies, so more likely to be detected in drinking water

• Persistence and mobility (PMT, vPvM) criteria now being used by European regulators as bioaccumulation (PBT-based regulations) described to be marginally effective to protect drinking water supplies

33

https://www.umweltbundesamt.de/sites/default/file

s/medien/421/dokumente/01_uba_eisentrager_pm

t.pdf

https://www.umweltbundesamt.de/sites/default/files/medien/421/dokumente/01_uba_eisentrager_pmt.pdf

© Arcadis 2016

August 14, 2020 34

Short chain replacement PFAS more mobile so more potential to impact drinking water

PBT Applicability?

• For drinking water quality, PBT-based regulations are only marginally

effective

• PBT aimed to protect food chain, not drinking water?

• In contrast, persistent and mobile organic compounds (PMOCs) are more of

a concern for water quality because, like PCBs, they can persist in the

environment, but they are not removed from water by sorption processes due

to their high polarity and thus excellent water solubility

• Therefore, they may end up in drinking water, posing a potential risk to

human health

• Umweltbundesamt (UBA) suggesting alternative assessment frameworks:

• PMT Persistent Mobile Toxic

• vPvM very Persistent and very Mobile as potential Substances of Very High Concern

© Arcadis 2016 35July 2016

Concerns over short chain PFAS - Overview

Persistent

• Based on read-across from long chain PFAS

• Long-range transport and findings in remote areas

Mobility and Exposure of Organisms

• Potential to contaminate drinking water resources

• Difficult to be removed from water

• Binding to proteins

• Non-negligible half-lives in organisms

• Enrichment in plants

Toxic

• No indications of ecotoxicity

• Toxicity in humans to be assessed

• Potential endocrine disruptor


Foams

36

© Arcadis 2016

• FP foams (fluoroprotein foams) used for hydrocarbon storage tank protection and marine applications.

• AFFF (aqueous film forming foams) used for aviation, marine and shallow spill fires and AR-AFFF (alcohol resistant aqueous film forming foams),

• FFFP foams (film forming fluoroprotein foams) used for aviation and shallow spill fires and AR-FFFP (alcohol resistant film forming fluoroprotein foams)

• PFAS foams contains both polyfluorinated and perfluorinated compounds

August 14, 2020 37

Class B Firefighting Foams

Timeline of AFFF addition to the DoD Qualified Products Listing (certified to MIL-F-24385 specifications).

© Arcadis 2016

PFAS Foams being Replaced

• C8 (PFOS and PFOA) generally phased-out

• C8 replaced with compounds with shorter (C6) perfluorinated chains

• C4, C6 PFAS are less bioaccumulative, but extremely persistent and more mobile in aquifer systems vs C8 - more difficult and expensive to treat in water.

• Solutions for characterizing all PFAS species important to cover current and future risks / liabilities

• Regulations addressing multiple chain length PFAS (long and short) are evolving globally – PFHxA ban coming

• Fluorine free (F3) foams contain no persistent pollutants

• F3 foams pass ICAO tests with highest ratings for extinguishment times and burn-back resistance and are widely available as replacements to AFFF

• Lastfire Independent Large Scale Storage Tank Test Program Results 2018: “It is not possible to state, for example, that all C6 foams demonstrate better performance than all FF foams and vice versa”


AFFF

FFFP

FP

AR-AFFF

AR-FFF

© Arcadis 2016

July 2016 39

Breakdown products of the C6 FT Foam: multiple intermediates to eventually form short-chain PFCAs

C6 Fluorotelomer Foam

Source: Weiner et.al. 2013

Stable Intermediate

Precursor

© Arcadis 2016

US Regulatory Heat Map

40

Proposition 65 (Safe Drinking Water and Toxic Enforcement Act)

Three routes of exposure: Occupational, Consumer, Environmental

Bounty hunter provision (¼ and ¾)

2018: Listing of PFOA as developmental toxicant

2019: Discharge prohibition comes into effect

Regulations Relevant to PFAS Containing Foam (AFFF, FFFP, FP) Usage

California

Kentucky

Washington

2018: Ban on training with PFAS foams

2019: Duty of manufacturers to inform users

2020: Ban on sale of PFAS firefighting foams

2024: Permitted exemptions expire (i.e. tank storage)

Updated March 12th 2020

Arizona Virginia

Georgia

2019: HB458 ruling restrict the use of firefighting foams containing PFAS for training and testing

while allowing continued use for real world fires

2020: Ban on uncontained release of PFAS foams, unless it’s an emergency

2019: Restrictions on the use of firefighting foams containing PFAS for

training and testing while allowing continued use for real world fires2019: Prohibiting discharge or other testing or training uses of PFAS-

containing class B firefighting foam carves out usage "required by law

or federal regulation"

https://chemicalwatch.com/78075/expert-focus-us-states-outpace-epa-on-pfas-firefighting-foam-laws#overlay-strip

https://chemicalwatch.com/83098/michigan-house-passes-bills-on-pfass-in-firefighting-foam

https://chemicalwatch.com/92626/wisconsin-to-restrict-pfas-containing-firefighting-foams

https://chemicalwatch.com/86978/new-york-state-to-restrict-firefighting-foams-containing-pfass#overlay-strip

Colorado

2019: Law prohibits the use of class B firefighting foam that

contains PFAS for training purposes, and violations may

result in imposition of a civil penalty

Limits the sale of PFAS firefighting foam, and requires

manufacturers to notify their customers of this law.

Addresses PPE by requiring PPE manufacturers to disclose

whether their product contains PFAS

Minnesota

2019: Law prohibits class B firefighting foam containing PFAS chemicals for testing or training, unless required by federal law, but excludes from

this ban use of AFFF in emergency firefighting and fire prevention activities

Any release of class B firefighting foam containing PFAS must be reported within 24 hours.

Prohibited PFAS-containing flame-retardants in residential products, like furniture, mattresses, textiles and window coverings

Also addresses products that contain organohalogen flame retardant compounds as a group

Michigan

2019: Bill HB 4390 would ban the use of PFAS-containing foam during firefighting training,

beginning on 31 December 2023. And until that date, firefighters would need to be

instructed in the proper use, handling and storage of the foams, as well as on containment

and proper disposal.

Bill HB 4391 outlines the "best health practices" for using, handling and storing the foam,

including decontamination of a firefighter’s body and equipment.

Bill HB 4389 would require that fire departments submit a written report to the State within

48 hours of using an AFFF

Wisconsin

2020: Law bans the use of firefighting foams with intentionally added per- and polyfluoroalkyl

substances (PFASs) for training purposes. The foams will be allowed for use in emergency

firefighting and testing purposes, although testing facilities must implement "appropriate containment,

treatment, and disposal or storage measures to prevent discharges of the foam to the environment."

[email protected]

New York

2019: Law bans the use of PFAS-containing class B firefighting foams for training

purposes, and will prohibit their manufacture, sale or distribution two years later. Certain

exemptions, such as when the products’ use is required by federal law, or to fight fires at

oil refineries or chemical plants.

https://chemicalwatch.com/78075/expert-focus-us-states-outpace-epa-on-pfas-firefighting-foam-laws#overlay-strip

https://chemicalwatch.com/83098/michigan-house-passes-bills-on-pfass-in-firefighting-foam

https://chemicalwatch.com/92626/wisconsin-to-restrict-pfas-containing-firefighting-foams

https://chemicalwatch.com/86978/new-york-state-to-restrict-firefighting-foams-containing-pfass#overlay-strip

mailto:[email protected]

© Arcadis 2016

Regulation of PFHxA• EU proposal to limit the use of PFHxA related substances

(precursors) – December 2019;

• Rationale:

• “Fulfils the P-criterion and vP-criterion”

• “Mobility and long range transport potential” and “unpredictable and irreversible adverse effects on the environment or human health over time”

• Exemptions (5 years) are in place for certain uses:

• Hard chrome plating;

• Photographic coatings;

• Firefighting foams – Emergency use only

• There is no exemption for testing (unless all releases contained) or training with fire fighting foams.

• Exemptions (12 year) are in place for Class B firefighting foams used to protect storage tanks with a surface area above 500m2

• Military users exempted – Requirement that during training foam contained and disposed of safely

• The EU considers the restriction practical as it is affordable, implementable, and manageable

© Arcadis 2016

www.lastfire.org.uk

Research Work – Rational Progression - more than 200 tests

Small scale

Simulated tank fire

Critical application rates

Spill fire

Critical application rates

Larger scale

“Real life” Application

NFPA rates

Phases have included

Different foams

Different nozzles

Different application methods

Different rates

Different fuels (including crude)

Different preburns

Fresh/Salt water

Longer flow

“Real life” Application

NFPA ratesSubsurface tests

Hybrid Medium

Expansion

Self expanding

foamVapour

suppression

Further obstructed spill

fire testing

© Arcadis 2016

Royal Danish Airforce in action using F3 foams

43

Performance of F3 Foams - Defence

“My experience is that fluorine free foam works flawlessly. We have used it in two major incidents, and we are using it for training purposes”

“When it comes to the extinguishing capability of the

fluorine free foam, there are, from my point of view, no

difference compared to the old AFFF foam containing

PFAS. It works exactly as good as the old stuff.”

“Put you self in the place of a crewmember trapped in a

fuselage engulfed in flames. Ask yourself a question;

would I trust the fluorine free foam? I would.”

https://www.linkedin.com/pulse/high-flow-fluorine-free-foam-lars-andersen/

Lars Andersen, Fire Chief, Royal Danish Airforce:

https://www.linkedin.com/pulse/how-fluorine-free-foam-does-work-practice-lars-andersen/

Experienced End User Perspective –F3 Foams work flawlessly

https://www.linkedin.com/pulse/high-flow-fluorine-free-foam-lars-andersen/

https://www.linkedin.com/pulse/how-fluorine-free-foam-does-work-practice-lars-andersen/

© Arcadis 2016 44

Use of F3 Foams – Oil & Gas

Oil & Gas Sector Complete Conversion to F3

Equinor (formerly Statoil) major Scandinavian

petrochemical company switched completely to

fluorine-free firefighting (F3) foam from 2013

for both its onshore and offshore (North Sea)

operations,

after having carried out extensive testing and due

diligence on alternatives to AFFF before changing

over.

HOCNF – The Harmonised Offshore Chemical Notification Format used to accredit F3 foams Equinor operates 42 fields on the Norwegian Continental

Shelf (NCS) representing 80% of all production on theNCS, producing 2.5 million barrels per day oil and gas,equivalent to 50% of total production for the North Seaincluding the Norwegian sector

© Arcadis 2016

GreenScreen CertifiedTM

Independent Certification of Environmental Profiles for Firefighting Foams

• Provision of a full product inventory from foam manufacturers to

Clean Product Action under a confidentiality agreement

• Clean Product Action reviews all relevant environmental and

human health data

• Data requirements vary by certification level and include :

• GreenScreen List TranslatorTM scores and GreenScreen

Benchmark scores

• Product-level acute aquatic toxicity data for fish, aquatic

invertebrates and algae

• Ingredient-level aquatic toxicity and fate data meet USEPA

Safer choice criteria (Master criteria or Direct Release criteria)

• Restricted ingredients:

• Organohalogens, PFASs, Siloxanes, Alkyl Phenols &

Alkylphenol Ethoxylates

• Three levels of certification: Bronze, Silver and Gold

PR

AC

TIC

ALI

TIES

OF

TRA

NSI

TIO

NIN

G T

O F

LUO

RIN

E FR

EE F

OA

M C

ASE

STU

DIE

S

46

NEXTPREVIOUS

Case Study: PFAS Rebound into F3 One year after changeout of hangar to F3 using a dual water flush:• PFAS residual up to 1.6 g/L in F3 foam lines;• Fire Water Supply remains impacted

Significant rebound of PFAS into F3 Foams after two water flushes

Sampling Locations

Sum

of P

FA

S T

op A

ssay

(ug/L

)

© Arcadis 2016

Case StudiesSystem Decontamination

Cleaning agent and TOP assay Required for Effective DecontaminationAugust 14, 2020 47

0

50,000

100,000

150,000

200,000

250,000

300,000

350,000

To

tal P

FA

S (

ng

/L)

Foam Tank Cleanout – TOP Assay

0

10,000

20,000

30,000

40,000

PFOS

PF

OS

Co

nce

ntr

atio

n (

ng

/L)

Sewer Decontamination Trial

Baseline Water

Cleaning Agent

Final Water

2 1,900 970 1,000

38,000

44

Control

1st H2O

Caustic

2nd H2O

CleaningAgent

3rd H2O

Pre-TOP

Post TOP

2,480

153,000

326,000

3,840 78 3,880

Sequential Sequential

© Arcadis 2016

Foam Disposal

• Fluorinated fire fighting foam comprise a complex waste

• Dispensed fluorinated foam and foam concentrates cannotbe treated using biological waste water treatment plants i.e.

– Municipal sewage treatment

– Publically operated treatment works (POTW)

• All fluorosurfactants / PFASs in foams are non-biodegradable, PFASs are extremely persistent

• Significant challenges and costs disposing of fluorinated fire fighting foams i.e. AFFF, FP, FFFP and their AR-variations

• Incineration of liquids containing PFASs problematic in U.S.

• Confirm that fluorine free foams100% biodegradable, so are significantly easier to dispose of via conventional biological treatment methods i.e. POTW, sewage treatment

PFAS are extremely persistent, some biotransform into others but none biodegrade

persistence = non-biodegradable

non-biodegradable = not treated biologically

© Arcadis 2016

Incineration

August 14, 2020 49

• 1,000 to 1,200 ºC (1,800 – 2,200 ºF) required to completely degrade PFOS

• Expensive and energy intensive options

• Hydrogen Fluoride management essential

• Lower temperature incineration of PFASs can produce toxic intermediates (e.g. perfluoroisobutylene) or potent greenhouse gases (CF4, C2F6 etc.)

• Cement kilns also being employed, for effective high temperature destruction with Ca(OH)2 to create CaF2

• Comprehensive analysis of all gaseous emissions required for any thermal treatment

https://toxnet.nlm.nih.gov/cgi-bin/sis/search/a?dbs+hsdb:@term+@DOCNO+7708

https://toxnet.nlm.nih.gov/cgi-bin/sis/search/a?dbs+hsdb:@term+@DOCNO+7708

© Arcadis 2016

Evolving Foam Treatment Options

August 14, 2020 50

• Treatment trains required for complex wastes such as dispensed foam and concentrates

• Sonolysis using ultrasound proven at laboratory scale and being scaled up

• Ultrasound causes cavitation of bubbles with extremely high temperatures and plasma on the surfaces of the bubbles resulting in destruction of PFASs.

• Ultrasound trials progressing using AFFF foam concentrates

• Foam concentrate pretreatment prior to sonolysis essential

• Potential to receive samples of AFFF for testing

• Options to retain and store AFFF concentrates until more sustainable treatment technologies are commercially available

Fate and Transport

© Arcadis 2016

Transport Pathways

8/14/2020 52

© Arcadis 2016

Vapor Phase Transport -Mainly neutral precursors

Longer transport potential~20 days atmospheric lifetime (8:2 FtOH)

Atmospheric transformation of precursors to other PFAS by reaction with:NOx, OH•, O3, O2

Particle phase/ Aerosol transport –PFAAs and Precursors

Wet Deposition of Vapor-Phase PFAS

Dry Deposition of Particle –Associated

PFAS

Wet Deposition of Particle –Associated

PFAS

Shorter transport potential~3-5 days atmospheric lifetime (PM2.5)

PFAS Atmospheric Fate & Transport

PFOA associated with small particles (<0.14 um) and PFOS associated with larger particles (1.38 to 3.81 um) (A. Dreyer et al. Chemosphere 2015)

© Arcadis 2016

Groundwater

• PFCs detected in 26% of groundwater sites

• Detection even at “low risk” sites

Surface Water

• PFCs detected at 52% of surface water sites (drinking water abstractions)

• PFCs detected at 67% “high risk” sites

• The Environment Agency PFC monitoring (2008)

• Groundwater sampling

• Conducted at 219 sites in England and Wales (6.5% EA network)

• The majority of sites were in areas of potential sources eg. airfields

• “Low risk rural sites” comprised 5%

• Surface water sampling

• Drinking water abstractions (42 sites)

• “Higher risk sites” (39 sites) eg. effluents from sewage works

• Limits of detection were 0.1 ug/L so above the new US EPA standards at 0.07 ug/L

© Arcadis 2016

PFAS in European Surface Waters

July 2016 56


River PFOS (ng/l) Flow(m3/s)

Scheldt (Be, NL) 154 -

Seine (Fr) 97 80

Severn (UK) 238 33

Rhine (Ge) 32 1,170

Krka (Sl) 1,371 50

© Arcadis 2016

PFOS EQS Exceedances

8/14/2020 57

© Arcadis 2016

Subsurface Retardation of PFAS in Groundwater• Hydrophobic interaction

• Predominant sorption mechanism for long chain PFAS

• Organic rich soils retard movement of PFAS

• foc increases -> Kd increases

• Oil and other organics may also increase sorption

• Electrostatic effects

• Positively charged PFAS (i.e. some precursors) sorb to negatively charged minerals

• Anionic minerals (clays etc.) repel anionic PFASs

• Negatively charged PFAS sorb to positively charged minerals

• Under acidic pH, mineral surfaces tend to be more positively charge –promoting adsorption of PFAAs

• Electrostatic repulsion can decrease PFAS sorption

• High ionic strength dulls electrostatic repulsion; favoring adsorption

58

Subsurface Retardation of PFASs in Groundwater

Higgins & Luthy, 2006

Conceptual electrostatic effects

Conceptual repulsion


Li et al., 2018

© Arcadis 2016

0 5000 10000 15000 20000 25000 30000

5.0 - 5.5

4.0 - 4.5

3.5 - 4.0

3.0 - 3.5

2.0 - 2.5

1.0 - 1.5

0.0 -0.5

0 20000 40000 60000 80000 100000 120000

2.0-2.5mPOST TOP

2.0-2.5mPRE TOP

0.0-0.5mPOST TOP

0.0-0.5mPRE TOP

Vertical Soil Profiling with TOP Assay

PFBA PFPeA PFHxA PFHpA PFOA PFNA

PFOS

PFHxSPFHxS

PFOS

PFDS8:2 FTS 6:2 FTS

• Significantly more mass of amphiphilic PFASs in unsaturated zone vs saturated zone;

• Reduction in PFASs soil concentrations at groundwater level;• Precursors in ECF foams less mobile as cationic /

zwitterionic but biotransform to create PFHxS, PFOS,

PFPeS, PFBS not PFCAs• Soil extraction methods for PFASs targets anions so extraction of

cations/zwitterions likely gross underestimationAssessment methods for PFASs in soils evolving 06 February 2020 59

© Arcadis 2016 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Vertical Distribution of PFASs in Soils

0.01

0.1

1

10

100

1000

10000

Con

c.

(µg/k

g d

w)

Modified after Baduel et al. 2017

PFCAs (C4-10) PFSAs (C1-11) 6:2/8:2FTS

FASA (C3-8) 6:2

FTSAS

PFSaAm(C6/C8)

Vertical Distribution (fraction of the PFASs over 4 discrete depths)

0.5

1.0

1.5

2.0De

pth

(m

)

C4 C10 C1 C11 C3 C8


60August 14, 202006 February 2020 60

© Arcadis 2016

Increasing mobility of shorter perfluoroalkyl chain PFAS

C6 C4 C5 C3? C2?

C8 C7 C6 C4 C5 C3? C2?Hidden anionic mobile PFAA

precursors

Anionic precursor biotransformation

increases as aerobic conditions develop

Direction of groundwater flow

Anionic PFAA

dead end

daughters

0

0

C F S 08 17

0

00H3C 0

C 4H9

0

C8F17 S 0 0

0

00H3C 0

C 4H9

0

0

S 0C8F17

C F

0

0

S 08 17

0

0

C6F13

S 0

0

0

C8F17

0

0

S 0S 0 C8F17

0

0

S 0C8F17

0

S 0C8F17

0

0

S 0C6F13

0

C6F13

0

0

0

S 0S 0

0C6

F13

Source Zone - Hidden Cationic and Zwitterionic PrecursorsLess mobile as bound via ion exchange to negatively charged fine grain soils

(e.g. silts & clays). Precursor biotransformation is limited by the anaerobic redox

conditions created by the co-occuring hydrocarbons.F

N+

0

0H

0

00

C1H9

C F

H3C 0

0

0

S 08 17

0

0

S

N H

C 8F17

NH+

FF C

n

0

0 0H

NS

F

F C

F n0

0

H3C 00 C 4H9

0

0H

0

N+F

F

F C

F

C6F13

0

0

S 0 N

NNS

0 H

0

F

F C

F n

0

0-C5F11

0

H3C 0

0

00H3C 0

C 4H9

0 C4H9

0 0

C6F17 S 0

0

CH

CH

CH

CHCH

CH

CH

AFFF/FFFP/FP

CH 3

CH 3

CH 3

CH 3

CH 3

Hydrocarbon NAPL Short hydrocarbon plume

-300mV -200mVREDOX

ZONATION-100mV 0mV 100mV 200mV

C7C8

PFAS Source and Plume CSM


© Arcadis 2016

Long lasting sources of PFAAs

August 14, 2020 62

• The unsaturated zones continue to be a source of

PFASs to the groundwater after 18 years (FTA-1)

and 20 years (infiltration beds) of inactivity.

• Anoxic conditions may have allowed for the

observation of differential transport through the

elimination or reduction of in situ PFAA production

from precursors.

• Some precursors are quite mobile at this field site

• Results indicate that shorter chain length PFAAs are

more mobile than PFOS both vertically and

horizontally.

© Arcadis 2016

August 14, 2020 63

• There is a secondary source to the east but surficial soils have been replaced

• Prior aerobic bioremediation in western source / plume targeting hydrocarbons, in the existing source enabled biotransformation of PFAA precursors.

PFAA Generation from Precursors

Eastern source area:

• Simply looking for PFAAs and not employing the TOP

assay may obscure the actual potential for PFAS

contamination

Conclusion:

McGuire et al., 2014


>

Point Source Management:

© Arcadis 2016

Groundwater Risks to Receptors

AFFF / FFFP / FP

Fire training

Incident Response Source – Pathway – Receptor

High concentration, spill site,

route via groundwater to receptor

e.g. drinking water well

Diffuse

Ground level impacts and

ground/surface water

Landfill Leachate

Municipal / Domestic WWTP

Industry & Manufacturing

Agricultural Land

Commercial / Domestic Products

Metal Plating

Car Wash/Wax

ASTs –Fuel storage (FFFP / FP) Grasshopper effect

via widening of source zones

e.g. concentrated plume intercepts crop spray irrigation to make secondary wider source area for more dilute plume

?

?

?

© Arcadis 2020

Phase 1 Investigations & GIS Vulnerability Tool

66

• Phase 1 Investigations of site portfolios to enable risk ranking

• Facilitated using GIS

• ArcWeb GIS platform enables external metadata linking and analysis with widgets

• Data generated in tabular form – requires manual interpretation

© Arcadis 2016

Excessive Costs

Risk based approaches not adopted in Germany August 14, 2020 67

http://greensciencepolicy.org/wp-

content/uploads/2016/09/Rolland-Weber-PFOS-

PFAS-German-activities-Final.pdf

© Arcadis 2016

Channel Island AirportSite Setting and Drivers

Setting

• Densely populated island communities

• Surface water dominated drinking water supply

• Airport – topographical high point within water supply catchments

• Shallow water table (<0.5m bgl)

Source

• Fire fighting foam usage

Drivers

• To provide a sustainable solution which would protect drinking water sources and the wider environment in the short, medium and longer terms

August 14, 2020

68

© Arcadis 2016

Incidents & Foam Usage

11 locations were identified whereairport firefighting foam containingPFAS had been used7 of these areas were found to beimpacted with PFAS.4 locations were then prioritised andwere subject to further investigationsand remediation, including:

Fire Training AreaFire Tender IncidentFire Station Area1999 Crash Site

Interim Emergency ResponseMeasures

Sampling adjacent to fire stationrevealed elevated PFOSconcentrations entering drainageLocalised dewatering quicklyestablished to prevent ongoingmigration of PFOS

August 14, 2020

69

© Arcadis 2016

Fate & Transport Modelling – Site Specific Detailed Quantitative Risk Assessment

• Site Detailed quantitative risk assessment (DQRA) of the delineated PFOS soil and water impacts

• Modelling for alternative locations and likely volumes of PFOS impacted material that would be moved during any airport redevelopment works.

• Site specific model in order to model accurately the anticipated migration of the PFOS

August 14, 2020

70

Treatment and Restoration


© Arcadis 2016

Sta

ge o

f D

evelo

pm

en

t

Practicability

Ma

ture

Exp

eri

me

nta

l

Not Viable Feasible

*AOP/ARP: Advanced oxidation processes/advanced reduction processes

Flocculation/

Electrocoagulation

Activated Carbon

Sonolysis

Ion Exchange

Ozofractionation

Polymeric Adsorbents

Electrochemical Treatment

AOP/ARP*

Photolysis

RO/NF**

**RO/NF: Reverse Osmosis/NanofiltrationEnzymes

Adsorptive/Separation

Destruction

Incineration

In Situ Foam Fractionation


PFAS Treatment Technologies for Water

74

Optimization Research

Development Research

Plasma

Injected Activated Carbon

© Arcadis 2016

*AOP/ARP: Advanced oxidation processes/advanced reduction processes

Incineration

Soil Stabilization

Ex Situ Thermal

Soil Washing

Ball Milling

AOP/ARP*

Excavation

PFAS Treatment Technologies for Soil/Sediment


Sta

ge o

f D

evelo

pm

en

t

Practicability

Ma

ture

Exp

eri

me

nta

l

Not Viable Feasible75

Fixation/Separation

Destruction

Optimization Research

Development Research

© Arcadis 2016 August 14, 2020 77

ACTIVATED CARBON (GRANULAR OR POWDERED)Surface Water

GroundWater

Point Of Entry (POE)

Systems

• AC can effectively remove PFOA/PFOS from water (>90%); 7 to 15 empty bed contact time (EBCT).

• Reactivation viable, improves sustainability, reduce cost ~15%, may also improve removal performance.

Applicability:

Benefits:

• Manages low PFOA/PFOS concentrations; low flow rates.

• Well understood, community friendly, rapid deployment, “de facto IRM.”

• Effectiveness decreases as PFAA chain length decreases; questionable removal of precursors. May be managed with longer EBCT?

• Competition with natural organic materials (NOM)/total organic carbon (TOC).

• Perpetual for the foreseeable future until destructive technologies develop (focus on optimization).

Limitations:


© Arcadis 2016

78

• Green lines: lead vessel GAC replacement

• Orange line: lead and lag GAC replacement

• Shortest chain (PFBA) breaks through first; PFBA is not regulated currently, but may be subject to future regulation

• PFBA C/C0 >1; implies sorption/desorption or transformation?

• Routine O&M/GAC change outs controls contaminant breakthrough; large GAC vessel sizes and lower flow rate will extended GAC lifetime

Dickenson and Higgins, 2016 Property of Arcadis, all rights reserved

Activated Carbon (cont.)

© Arcadis 2016

August 14, 2020 80

ANION/ION EXCHANGE

Zaggia et al 2016;

1 mg/L PFOA for 120 hr

• AIX can effectively remove PFAAs from water with effectiveness ranging from 10% to >90%.

• Reactivation methods available, though high throughputs may justify single use.

Applicability:

• Sensitive to site-specific geochemistry; methanol/brine reactivation may be required; comparative assessment of engineered resins challenged by inconsistent data reporting in the literature.

Limitations:

Benefits:

• Engineered resins (variable functional groups on the surface of polystyrene or polyacrylic resins) enable enhanced selectivity.

• Smaller equipment footprints, lower EBCT than AC (3 min versus 7 to 15 min).

• Recent field-test data suggests enhanced AC performance with AIX polish and demonstrated greater removal of PFHpA, PFNA, PFHxS, and PFBS.


© Arcadis 2016


81

Source: Edmiston 2019

Quaternary Amines

Polymers of Quaternary Amines

Perfluoroalkyl moiety (fluorophillicity)

Engineered adsorbents may

impart greater electrostatic affinity

and enable fluorophillic adsorption

Polymeric Adsorbents

“Scaffolding”

© Arcadis 2016

HRX Well® Description

The HRX Well* is a large-diameter horizontal well installed along the groundwater flowpath that is filled with treatment media for long-term in situ mass flux/discharge control

➢Passive in-situ treatment➢Many solid-phase reactive media options ➢Efficient use of reactive media➢Treatment train approach possible➢Not limited to high-permeability aquifers

➢Can be applied in relatively deep settings➢Limited above-ground footprint➢Minimal O&M➢No ongoing energy requirements➢Pumping can enhance treatment zone size

Impacted Groundwater

“Flow-

focusing”

*Patent US20120261125A1

Treated Groundwater

Treatment Media

Time

Co

nce

ntr

ation

© Arcadis 2016


ISS Reduce leachability

of PFASs to groundwater

Pragmatic alternative

due to cost of removal;

destruction concerns?

ISS does not

destroy/remove PFAS –

risk managed with long-

term GW monitoring

Soil Stabilization (ISS; Potentially with Solidification)

85

CSMs showing PFAS

shallow, proximal to

historical releases

© Arcadis 2016

0

2,000

4,000

6,000

8,000

10,000

5% PC Control 5% Modified Clayplus 5% PC

10% ModifiedClay plus 5% PC

5% AlOH/GACplus 10% PC

10% AlOH/GACplus 15% PC

To

tal P

FA

As

Po

st-

TO

P (

ng

/L)

Monitoring Event 1 - LEAF 1315 Interval T03 DPT-1

DPT-2

DPT-3

5% wt Reagent 1 5% PC




5% PC

Non Detect

Field-Scale Post Implementation Monitoring


Non Detect

86

© Arcadis 2016 Huang and Jaffe 2019

Biological Defluorination ofPFOA/PFOS

• 23% to 50% PFOA or PFOS reductions via enhanced or pure Acidimicrobium sp. strain A6 (either NH4

+ or H2 electron donors)

• Formation of acetate with sustained DOC mass balance, suggests synergistic A6 partial defluorination and heterotrophic species mineralization (enriched A6 cultures)

• PFOS may have more detrimental influence on A6 than PFOA

0

1

2

3

4

5

0 25 50 75 100

F (

in P

FA

S)

mM

time (d)

PFOA

PFBA

PFPeA

PFHxA

PFHpA

F-

Tot F

© Arcadis 2016

Electrochemical Degradation

August 14, 2020 89

• Electrochemical cells can degrade PFAS through direct electron transfer at the surface of the anode.

Applicability:

• Geochemical constituents may cause secondary concerns (i.e., chloride oxidized to perchlorate).

• Acidity around anode may facilitate PFOS sorption; needs further investigation. Confirmed effectiveness for sulfonates?

• Short chain PFAAs appear to be recalcitrant at low current density (<50 mA/cm2).

• Lowest demonstrate concentration >1,000 ppt

Limitations:

Benefits:

• Provides a feasible destruction mechanism for concentrated PFAS waste streams at low flow rate.

• PFAS degradation confirmed (fluorine mass balance); effective for both laboratory and real groundwater/wastewater.

• Less energy consumption than sonolysis.

0.1

1

10

100

1000

10000

0 4 8 12

[C] (m

g/L

)

Time (hr)

Cl- Cl2 ClO3- ClO4-

Gomez-Ruiz et al 2017

1

100

10,000

1,000,000

Influent 98% Power 99.7% Power

∑P

FA

S (

pp

t)

HAL = 70

1,625,000

4,22033,040

0.15 kW-hr/L

0.26 kW-hr/L


© Arcadis 2016

Sonolysis

August 14, 2020 90

• Ultrasound applied to water results in successive rarefaction/compression of microbubbles ultimately yielding cavitation with extremely high temperatures on the surfaces of the bubbles resulting in pyrolysis of PFAS.

Applicability:

Benefits:

• Can reliably destroy concentrated PFAS waste streams with literature supported fluoride mass balance.

• Opportunities to use green energy sources as technology develops (i.e., solar power).

• PFOA rate > PFOS rate. PFOS will require longer residence times and/or more energy. Effective below 10,000 ppt?

• Requires specialized equipment and skilled implementation.

• High energy consumption and low flow rates.

Limitations:

$1

$10

$100

$1,000

$10,000

$100,000

0.05 0.5 5 50 500

FLOW RATE (GPM)

ENERGY COST (USD)Assumes $0.12/kW-hr and 10 hr/d operation time

0.3 kW-hr/L


© Arcadis 2016

Sonolysis: The Effect of Pressure Wave Propagation

Pressure Wave

Distribution of liquid molecules

Bubble growth and collapse

Increasing bubble instability and eventual collapse

Compression Compression CompressionIncre

asin

g p

ressu

re

Relax RelaxSound energy applied to a liquid propagates as a

pressure wave, creating microbubbles.

The pressure wave results in successive

compression and rarefaction (elongation) of

the microbubbles.

The microbubbles become unstable and eventually collapse,

releasing energy in the form of heat (quasi-

adiabatic) up to 5,000 K.

Property of Arcadis, all rights reserved Adapted from Mason 200391

© Arcadis 2016

0

50

100

150

200

250

300

350

0

4

8

12

16

20

0 60 120 180 240

Flu

ori

ne

Co

nce

ntr

atio

n (

μM

)

PF

OS

Co

nce

ntr

atio

n (

µM

)

Treatment Time (minutes)

Initial PFOS = 17.5 μM

Fluorine in PFOS = 297.5 μM

Sonolysis – Proof of Concept Testing


*corr

ecte

d f

or

adsorp

tion

*corr

ecte

d f

or

adsorp

tion

AkHz PFOS

AkHz Fluorine

BkHz PFOS

BkHz Fluorine

CkHz PFOS

CkHz Fluorine

DkHz PFOS

DkHz Fluorine

92-94% Fluorine Release

(B to D kHz)

91-97% PFOS Reduction

(B to D kHz)

92

© Arcadis 2016

0.1

1

10

100

1000

10000

0 4 8 12

[C] (m

g/L

)

Time (hr)

Cl- Cl2 ClO3- ClO4-

Electrochemical Degradation

94

• Electrochemical cells can degrade PFAS through direct electron transfer at the surface of the anode.

Applicability:

• Geochemical constituents may cause secondary concerns (i.e., chloride oxidized to perchlorate).

• Acidity around anode may facilitate PFOS sorption; needs further investigation. Confirmed effectiveness for sulfonates?

• Short chain PFAAs appear to be recalcitrant at low current density (<50 mA/cm2).

Limitations:

Benefits:

• Provides a feasible destruction mechanism for concentrated PFAS waste streams at low flow rate.

• PFAS degradation confirmed (fluorine mass balance); effective for both laboratory and real groundwater/wastewater.

1

100

10,000

1,000,000

Influent 0.15 kW-hr/L 0.26 kW-hr/L

∑P

FA

S (

pp

t)

HAL = 70

1,625,000

4,22033,040

Property of Arcadis, all rights reserved Adapted from Gomez-Ruiz et al 2017

98% reduction 99.7%

reduction

© Arcadis 2016

Arcadis Federally Funded R&D

Chemical reactivation of

spent adsorbents (SERDP)

Polymeric adsorbents (SERDP)

Assessing PFAS ecological risk

(SERDP)

IDW Treatment with E-Beam

(SERDP)

Standard and tiered approach to characterizing PFAS at FTAs

(ESTCP)

Mobile laboratory validation (ESTCP)

Sub-micron PAC ceramic

membrane filtration (ESTCP)

Passive sampler development for PFAS (SERDP)

Biotransformation and potential mineralization (PFOS, PFOA,

PFHxS) (SERDP)

Microbially-mediated

defluorination of PFAS (SERDP)

Ex-situ soil washing for PFAS

(ESTCP)

Treatment of groundwater for

PFAS using ozofractionation

(ESTCP)

In-situ soil stabilization for PFAS source areas (BAA)

Surface water

collection pondtreatment for PFAS (BAA)

Property of Arcadis, all rights reserved 95

Completed In ProgressFollow on Funding

FundedInvited for

Full Proposal

BAA

© Arcadis 2016

Summary

• Short Chains and Ethers replacing Long Chains

• Precursors form PFAAs

• Escalating regulatory and political attention globally

• Consider porfolio assessment, evaluating use and environmental sensitivity

• Volatile PFASs with long range transport contributing to low level background concentrations

• Evaluation of exposure pathways and development of site specific CSMs essential for PFAS management

• A significant mass of PFASs in source areas can bleed PFASs to form plumes for decades

• Long term liabilities and ongoing use to manage considering ultrapersistent mobile contaminants

the emerging issue per- polyfluoroalkyl substances … · • fluorotelomer sulfonic acids (ftss)...

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