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Taking Action on PFAS in Landfill Leachate

Steve Sliver

Michigan PFAS Action Response Team

517-290-2943| SliverS@Michigan.gov

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Per-and polyfluoroalkyl substances (PFAS)

• Strong carbon-fluorine bonds

• Surfactants

• Hydrophobic(repels water) and oleophobic (repels oil, fat, grease)

• Heat resistant

• Began developing in 1940’s

• 5,000+ compounds today

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Some Common PFAS Abbreviations

• Perfluorooctanoic acid (PFOA)

• Perfluorooctane sulfonate (PFOS)

• Perfluorononanoic acid (PFNA)

• Perfluorohexane sulfonic acid (PFHxS)

• Perfluorobutane sulfonic acid (PFBS)

• GenX

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PFAS Uses

Chemicals and

PharmaceuticalsElectronicsAerospace Apparel

Building and

Construction

Aqueous Film

Forming FoamSemiconductorsOil & Gas Energy

Healthcare and

Hospitals

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Why the Concern?

• Pervasive

• Persistent

• Bioaccumulative

• Associated with adverse health effects

• Scarcity of information in scientific literature

• Incomplete regulatory structure5

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1 ppt = 1 drop in 20 Olympic pools

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Michigan PFAS Action Response Team (MPART)

• Unique multi-agency approach

• Leads coordination and cooperation among all levels of government

• Directs implementation of state’s action strategy

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MPART Response

• Protect Public Health• Standardize sampling and analytical• Study occurrence• Identify sources and source pathways• Study environmental transport and

fate• Study ecological effects• Educate• Prevent future contamination• Develop standards

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MI Standards

Surface water quality ✓ 11/12 ppt PFOS✓ 420/12,000 ppt PFOA

Groundwater cleanup✓ 70 ppt PFOA/PFOS✓ GSI per surface water quality

standardsDrinking water

✓ 70 ppt PFOA/PFOS lifetime health advisory recommendation

❑MCLs

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IPP Initiative

• Industrial pretreatment program

• Screen industrial users

– Includes landfills

• Test POTW discharge

• Test biosolids

• Reduce or eliminate PFAS

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MI Landfill Leachate Initiative

• Sampling and analytical guidance

• Relate PFAS levels to

– Age and type of waste

– Leachate management

– Operations

– Landfill design

• Partnership with industry

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March 2019 Report

• Industry-wide study for context

• 35 active MSW landfills

• PFOA and PFOS

• One data point

• Foundation for next steps

• https://www.michiganwasteandrecyclingassociation.com/

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2019 MWRA/NTH

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2019 MWRA/NTH

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2019 MWRA/NTH

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2019 MWRA/NTH

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2019 MWRA/NTH

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Going Forward on Leachate

• Workgroup

• Evaluate options

– Monitoring

– Best management practices

– Compliance schedules

– Treatment

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Leachate Treatment and Disposal

• Granular Activated Carbon (GAC)

• Reverse Osmosis (RO)

• Deep well injection

• Treatment Technology Roundtable May 10, 2019

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Sites and Corrective

Action• Sources of

groundwater contamination over 70 ppt PFOS+PFOA

• Standards enforceable under state cleanup and waste programs

• 7 landfills so far

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Mobility

• Highly mobile

• Unconventional

• Affected by organic carbon, pH, clay content

• Current models lacking

• More studies needed

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Landfill Corrective Action

• Prioritize active and closed Type II (MSW) and Type III (industrial)– History of releases

– PFAS in leachate

– Proximity to groundwater receptors

– Waste types

• Goal– Responsible parties test groundwater at all high

priority sites by the end of the year

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High Priority

• 48 sites designated high priority for PFAS sampling

– current or historic groundwater impacts

– potential drinking water receptors are proximate

– Excludes 100% Cement Kiln Dust (CKD) or Ash landfills that otherwise meet first 2 criteria

• Sampling requested at 26 sites

– Results from 4 sites are in and all have PFAS

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Medium Priority

• 43 sites designated medium priority sites for PFAS sampling

– current or historic groundwater impacts

– no potential drinking water receptors proximate to the site

– includes CKD and Ash sites

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Low Priority

• 43 sites designated low priority for PFAS sampling

– No current or historic groundwater impacts

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Going Forward on Corrective Action

• Ongoing evaluation per priorities

• Initiate corrective action process when PFAS are found in groundwater

– Initiate testing of drinking water wells downgradient

– Implement alternate water for impacted drinking water

• Integrate PFAS into groundwater monitoring

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Michigan Department of

Environment, Great Lakes, and Energywww.Michigan.gov/EGLEwww.Michigan.gov/PFASresponse