EPA Takes Additional Water Actions as Part of Its PFAS Strategic Roadmap

Adding Five PFAS to Contaminated Site Cleanup Tables

In April 2022, the EPA published three additional water commitments as part of its PFAS Strategic Roadmap. The update includes a new method to screen for PFAS in water at the parts per billion level. The new method, Screening Method for the Determination of Adsorbable Organic Fluorine (AOF) in Aqueous Matrices by Combustion Ion Chromatography (CIC) will measure the total concentration of substances containing a carbon-fluorine bond. This draft method EPA 1621 has been successfully validated by a single laboratory. Multi-laboratory validation will be completed in the summer of 2022 and the EPA intends to publish an updated method later in 2022. Existing methods report at the parts per trillion level now for target analytes, so this new method will be used mostly for screening; Apex Companies has successfully utilized EPA 1621 as an additional screening method to determine potential PFAS mass not accounted for by the standard compound list.

In a memorandum published on April 28, 2022, the EPA also published revised guidance for addressing PFAS in National Pollutant Discharge Elimination System (NPDES) permits where EPA is the permit issuer and control authority. For applicable industrial direct dischargers, effluent must be monitored during draft EPA method 1633 and results must be reported on Discharge Monitoring Reports (DMRs). Draft method 1621 can also be used in conjunction with draft method 1633, if appropriate. Dischargers with permits must also follow best management practices (BMPs) with specific BMPs for PFAS-containing firefighting foams. These BMPs include:

1. Prohibiting the use of AFFFs in stormwater permitted activities other than for actual firefighting;
2. Eliminating PFOA- and PFOS-containing AFFF; and
3. Requiring immediate cleanup in all situations where AFFFs have been used, including diversions and other measures that prevent discharges via storm sewer systems.

Finally, as part of the April 2022 PFAS Strategic Roadmap update, EPA is also developing national recommended ambient water quality criteria for PFOA and PFOS. They have published draft criteria (chronic criteria include 94,000 ng/L PFOA and 8,400 ng/L PFOS over a 4-day average and not to exceed more than once in three years). The draft criteria also include fish tissue recommendations to protect aquatic life from bioaccumulation. Following the comment period, the EPA intends to issue final PFOA and PFOS recommended criteria.

More recently, on May 18, 2022, EPA added five PFAS (PFOA, PFOS, HFPO-DA [GenX], PFNA and PFHxS) to the Contaminated Site Cleanup Tables or Regional Screening Levels (RSL) Generic Tables. The new tables can be downloaded in PDF or XLS format. The EPA selected levels using the most updated information from the Agency for Toxic Substances and Disease Registry (ASTDR) 2021 toxicological profiles and final peer reviewed EPA toxicity values.

RSLs are used to identify sites that may require further investigation and Regional Removal Management Levels are used to support EPA’s decision for removal action under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). This update also includes several chemicals with new toxicity values that have been added based on ATSDR updates and several with toxicity changes based on EPA Office of Water updates. The EPA is also working on updating health advisory levels for PFOA and PFOS and to develop a proposed PFAS National Drinking Water Regulation for publication in fall 2022.

EPA Regional Screening Levels (TR=1E-06, THQ=1.0)
Per- and Polyfluoroalkyl Substances (PFAS)	Resident Soil (mg/kg)	Industrial Soil (mg/kg)	Tapwater (ng/L)	Protection of Groundwater SSL (mg/kg)
~Hexafluoropropylene oxide dimer acid (HFPO-DA)	0.23	3.5	60	–
~Perfluorobutanesulfonic acid (PFBS)	19	250	6000	0.0019
~Perfluorohexanesulfonic acid (PFHxS)	1.3	16	390	0.00017
~Perfluorononanoic acid (PFNA)	0.19	2.5	59	0.00025
~Perfluorooctanesulfonic acid (PFOS)	0.13	1.6	40	0.000038
~Perfluorooctanoic acid (PFOA)	0.19	2.5	60	0.00091

EPA Regional Management Levels (TR=1E-04, THQ=3.0)
Per- and Polyfluoroalkyl Substances (PFAS)	Resident Soil (mg/kg)	Industrial Soil (mg/kg)	Tapwater (ng/L)
~Hexafluoropropylene oxide dimer acid (HFPO-DA)	0.70	11	180
~Perfluorobutanesulfonic acid (PFBS)	57	740	18000
~Perfluorohexanesulfonic acid (PFHxS)	3.8	49	1200
~Perfluorononanoic acid (PFNA)	0.57	7.4	180
~Perfluorooctanesulfonic acid (PFOS)	0.38	4.9	120
~Perfluorooctanoic acid (PFOA)	0.57	7.4	180

EPA Draft Recommended Freshwater Aquatic Life Water Quality Criteria for PFOA and PFOS
Criteria Component	Acute Water Column (CMC)1	Chronic Water Column (CCC)2	Invertebrate Whole‑Body	Fish Whole-Body	Fish Muscle
PFOA Magnitude	49 mg/L	0.094 mg/L	1.11 mg/kg ww	6.10 mg/kg ww	0.125 mg/kg ww
PFOS Magnitude	3.0 mg/L	0.0084 mg/L	0.937 mg/kg ww	6.75 mg/kg ww	2.91 mg/kg ww
Duration	1-hour average	4-day average	Instantaneous3
Frequency	Not to be exceeded more than once in three years, on average	Not to be exceeded more than once in three years, on average	Not to be exceeded more than once in ten years, on average

Source: https://www.epa.gov/system/files/documents/2022-04/pfoa-pfos-draft-factsheet-2022.pdf

mg/kg = Milligrams per kilogram (parts per million). ng/L = Nanograms per liter (parts per trillion). mg/L = Milligrams per liter (parts per million).

Keep following our blog for important updates as we continue to follow the EPA’s and state actions on PFAS.

¹ Criterion Maximum Concentration.
² Criterion Continuous Concentration.
³ Tissue data provide instantaneous point measurements that reflect integrative accumulation of PFOA or PFOS over time and space in aquatic life population(s) at a given site.