NHDES Submits Final Rulemaking Proposal for PFOA, PFOS, PFHxS and PFNA

News from the New Hampshire Department of Environmental Services

DATE: June 28, 2019      
CONTACT: Jim Martin, (603) 271-3710

NHDES Proposes New PFAS Drinking Water Standards
Final Rulemaking Proposal for PFOA, PFOS, PFHxS and PFNA

[CORRECTION: This press release has been updated to correct a minor error in describing a “non-transient public water system.” Non-transient public water systems are water systems serving the same 25 people more than 6 months per year.]

Concord, NH – The New Hampshire Department of Environmental Services (NHDES) has filed a final rulemaking proposal to establish Maximum Contaminant Levels (MCLs)/drinking water standards and Ambient Groundwater Quality Standards (AGQS) for four per- and polyfluoroalkyl substances (PFAS): perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), perfluorononanoic acid (PFNA) and perfluorohexanesulfonic acid (PFHxS) to ensure greater protection of public health related to the consumption of drinking water. The rulemaking proposal was filed today with the New Hampshire Joint Legislative Committee on Administrative Rules (JLCAR) for consideration at their July 18, 2019, meeting. If approved by JLCAR, the new rules are scheduled to become effective on October 1, 2019.
Using the most recent and best science available, NHDES is proposing the following drinking water standards that are protective for the most sensitive populations over a lifetime of exposure:

PFAS Final Proposed MCL and AGQS
PFOA 12 ppt
PFOS 15 ppt
PFHxS 18 ppt
PFNA 11 ppt

These MCLs are drinking water quality standards that non-transient public water systems (water systems serving the same 25 people more than 6 months per year) must comply with. An AGQS is the standard used to require remedial action and the provision of alternative drinking water at a contaminated site. It also dictates the conditions under which treated and untreated wastewater may be discharged to groundwater. Current law requires AGQSs be the same value as any MCL established by NHDES and also that they be at least as stringent as health advisories set by the U.S. Environmental Protection Agency (EPA). In 2016, NHDES adopted EPA’s health advisory for PFOA and PFOS as an AGQS at 70 parts per trillion (ppt) individually or combined.

To establish MCLs for PFOA, PFOS, PFHxS and PFNA, NHDES had to consider the extent to which the contaminants are found in New Hampshire, the ability to detect them in public water systems, the ability to remove the contaminant from drinking water, and the costs and benefits to affected parties that will result from establishing the standard, and then develop a MCL for each compound that is protective of the most sensitive population at all life stages.

Included with the final proposal, NHDES is providing a summary technical report on the development of the drinking water standards (MCLs) including an explanation of the health risk assessment for each compound and information on cost, benefit, occurrence, and ability to detect and treat these chemicals. That summary technical report can be found here: https://www.des.nh.gov/organization/commissioner/legal/rulemaking/index.htm#pdrinking

Additionally, NHDES has posted its response to public comments received during the public comment period on the initial proposal:


NHDES and NHDHHS have compiled a list of frequently asked questions and answers associated with PFAS, drinking water, and potential health impacts that can be found here: https://www4.des.state.nh.us/nh-pfas-investigation/?page_id=92

Since new drinking water standards may encourage private well owners to test their wells for the newly regulated compounds, NHDES has compiled an updated well testing fact sheet that can be found here:


Should you wish to consider or install PFAS treatment in your home or business, NHDES has compiled a fact sheet on treatment technologies for PFAS that can be found here: https://www4.des.state.nh.us/nh-pfas-investigation/?page_id=171

A discussion of the summary technical report with interested stakeholders will be conducted in the NHDES Auditorium (29 Hazen Dr. in Concord) on July 9, 2019, at 9:00 am. If you wish to attend please provide a courtesy RSVP via email to james.martin@des.nh.gov Attendees are reminded to bring a government furnished picture ID for entrance.

For additional information, please contact Jim Martin, NHDES Public Information Officer at (603) 271-3710.


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