Recommended Groundwater Standards (Cycle 11)

On November 6, 2020, DHS provided the DNR recommended groundwater standards for 22 substances.

This was the 11th time that the Department of National Resources (DNR) has requested the Department of Health Services (DHS) to develop recommended groundwater standards for the protection of public health. The table below summarizes these recommendations and additional details can be found in the letter sent to the DNR. In the coming months, DNR will begin rulemaking to adopt these recommendations.

Substance Recommended
Enforcement Standard(i)
Preventive Action Limit(i)
Chlorantraniliprole 16 mg/L 3.2 mg/L
Flumetsulam 10 mg/L 2 mg/L
Fomesafen 25 µg/L 5 µg/L
Perfluorooctane sulfonamide (FOSA) 20 ng/L(ii) 2 ng/L(ii)
Hexafluoropropylene oxide dimer acid (HPFO-DA; GenX)(iii) 300 ng/L 30 ng/L
Hexazinone 400 µg/L 40 µg/L
Metalaxyl 800 µg/L 160 µg/L
N-Ethyl perfluorooctane sulfonamidoethanol (NEtFOSE) 20 ng/L(ii) 2 ng/L(ii)
Perfluorobutanoic acid (PFBA) 10 µg/L 2 µg/L
Perfluorobutanesulfonic acid (PFBS) 450 µg/L 90 µg/L
Perfluorododecanoic acid (PFDoA) 500 ng/L 100 ng/L
Perfluorohexanoic acid (PFHxA) 150 µg/L 30 µg/L
Perfluorotetradecanoic acid (PFTeA) 10 µg/L 2 µg/L
Perfluoroundecanoic acid (PFUnA) 3 µg/L 0.6 µg/L
Saflufenacil 460 µg/L 46 µg/L
4,8-Dioxa-3H-perfluorononanoic acid (DONA) 3 µg/L 0.6 µg/L
Perfluorooctadecanoic acid (PFODA) 400 µg/L 80 µg/L
Perfluorohexanesulfonic acid (PFHxS) 40 ng/L 4 ng/L
Perfluorononanoic acid (PFNA) 30 ng/L 3 ng/L
Perfluorodecanoic acid (PFDA) 300 ng/L 60 ng/L
N-Ethyl Perfluorooctane sulfonamide (NEtFOSA) 20 ng/L(ii) 2 ng/L(ii)
N-Ethyl perfluorooctane sulfonamidoacetic acid (NEtFOSAA) 20 ng/L(ii) 2 ng/L(ii)

i The recommendations included in this table are reported as milligrams per liter (mg/L), micrograms per liter (μg/L), or nanogram per liter (ng/L). You can find more information about these units on our chemicals page.

ii DHS recommends a combined enforcement standard of 20 ng/L and combined preventive action limit of 2 ng/L for FOSA, NEtFOSE, NEtFOSA, NEtFOSAA, PFOS, and PFOA.

iii GenX is a trade name for hexafluoropropylene oxide dimer acid (HFPO-DA).

DHS did not recommend groundwater standards for some substances on the Cycle 11 list.

Due to limited health information, we were not able to recommend standards for 9-chlorohexadecafluoro-3-oxanonane-1-sulfonic acid (9Cl-PF3ONS; also known as F-53B Major); 11-chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS; also known as F-53B Minor); 4:2 Fluorotelomer sulfonic acid (4:2 FTSA); 6:2 fluorotelomer sulfonic acid (6:2 FTSA); 8:2 fluorotelomer sulfonic acid (8:2 FTSA); 10:2 Fluorotelomer sulfonic acid (10:2 FTSA); N-methyl perfluorooctane sulfonamide (NMeFOSA); N-methyl perfluorooctane sulfonamidoacetic acid (NMeFOSAA); N-methyl perfluorooctane sulfonamidoethanol (NMeFOSE); perfluorodecane sulfonic acid (PFDS); perfluoroheptanoic acid (PFHpA); perfluoropentanoic acid (PFPeA); perfluorotridecanoic acid (PFTriA); perfluoroheptanesulfonic acid (PFHpS); perfluoropentanesulfonic acid (PFPeS); perfluorododecanesulfonic acid (PFDoS); perfluorohexadecanoic acid (PFHxDA); and perfluorononane sulfonic acid (PFNS).


Our PFAS webpage has information on sources and health effects of PFAS.
The Agency for Toxic Substances and Disease Registry (ATSDR) has fact sheets on health risks of various substances.


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Last Revised: March 15, 2021