The MPCA has been working on issues related to PFAS since the early 2000s when we started addressing what were then called PFCs (perfluorinated chemicals) at four waste disposal sites in Washington County used by the 3M Company and testing ground water, surface water, and fish throughout the metro area. There have since been several periods of renewed interest and activity as we learned more about these chemicals and their potential effects on human health and the environment. For example, the Minnesota Department of Health first issued fish consumption advisories for PFCs in 2007. Later it was found that firefighting foams containing PFAS could contaminate ground water. A more recent issue is PFAS contamination at compost sites.
Throughout this period more scientific studies have shown PFAS is toxic at concentrations lower than previously known.
Current efforts by the MPCA to manage PFAS impacts in Minnesota range from working directly with landfill operators to developing water quality standards for PFAS. In addition, the Minnesota Department of Health has issued fish consumption advisories for lakes and rivers based on PFOS contamination.
Minnesota's water quality standards (WQS) have multiple classes that protect human health from pollutants in drinking water and fish tissue (aquatic consumption), and from pollutants encountered while recreating in water. These standards also protect aquatic communities.
While Minnesota does not have a statewide WQS for any PFAS, methods in rule can be used to develop site-specific water quality criteria (WQC). Site-specific WQC can support multiple regulatory programs and clean up actions. Because the methods are from an approved rule, the criteria does not need to go through rulemaking. The MPCA has and is continuing to develop WQC to support targeted actions in areas where PFAS is a concern.
Most of MPCA’s work to date on PFAS and water quality criteria or standards focuses on assessing the need to lower PFOS concentrations in fish.
MPCA is considering the need for additional WQC and, potentially, statewide WQS as necessary to protect human health and the environment from the risks of PFAS. This may include standards for PFAS sources of drinking water (Class 1 waters) or other beneficial uses such as fish consumption, recreation, and aquatic life consumption. More information about actions will be available as MPCA completes the next triennial review and develops our next WQS workplan for 2021 and beyond.
- Water-quality criteria development for PFAS
- Minnesota's triennial standards reviews
- Minnesota's Impaired Waters List
Soil quality and human health
The MPCA’s Water Quality Standards Unit also conducts risk assessments for soil and sediment. PFAS contamination in the East Metro also involves soils and as such need risk based values for decision-making. Soil reference values (SRVs) to protect human health from PFAS are found on the cleanup guidance webpage.
In many cases, PFAS is carried into the environment from facilities that do not manufacture or use significant PFAS compounds — facilities like landfills and municipal wastewater treatment facilities. MPCA is working with permit holders and other states to understand the opportunities to reduce the presence of PFAS in both landfill leachate and wastewater. MPCA has requested $1.4 million from the Legislative-Citizen Commission on Minnesota Resources (LCCMR) to better understand elevated levels of PFAS in waste streams (e.g., wastewater bio-solids, compost contact water, and landfill leachate). Research goals include:
- Analyze alternative disposal and treatment options and develop tools for managing PFAS‐contaminated waste streams.
- Evaluate and characterize PFAS concentrations in land‐applied biosolids; leaching from those wastes; and subsequent movement of PFAS into water and food.
For more information: LCCMR proposal
MPCA would like to conduct additional investigation into effluent concentrations and PFAS source identification at wastewater facilities. This effort will build on previous efforts to minimize PFAS at WWTPs, including some sampling done in the 2000s and some work done by individual facilities. MPCA would like to support municipal wastewater facilities in efforts to identify upstream sources and minimize PFAS waste streams.
MPCA is overseeing the cleanup of a number of sites that have PFAS contamination (e.g. disposal areas – 3M in the East Metro; firefighting foam – City of Bemidji, Duluth Air National Guard, plating industry - Douglas in St. Louis Park/Minneapolis). MPCA’s closed landfill program has begun investigating sites under its oversight for PFAS, to determine the extent PFAS presence and evaluate what may need to be done at the facilities where PFAS is present.
MPCA is implementing the Natural Resources Damages (NRD) settlement with 3M in the East Metro.
MPCA’s Toxics Reduction and Pollution Prevention program
MPCA’s Toxics Reduction and Pollution Prevention program are working on reduction of PFAS in firefighting foam, chrome plating, and food packaging, with related efforts in state and local government purchasing.
These activities focus on the presence of PFAS. Further work is needed to evaluate the sources and potential for reduction.
PFAS drinking water standards and sampling (MDH)
MDH is the lead on developing the state’s health based values for drinking water, which various MPCA regulator programs utilize (e.g. solid waste and Superfund). MDH has developed health based values for PFOS (15 parts per trillion - ppt), PFOA (35 ppt), PFHxS (47 ppt), PFBS (2,000 ppt), and PFBA (7,000 ppt). The federal health based guidance is 70 ppt for the combined concentrations of PFOS and PFOA. MDH’s Public Health Laboratory continually works to improve their analytical methods. MDH and MPCA also have conducted monitoring and treatment at a large number of public and private drinking water wells, most of which are in the East Metro area. Additional statewide sampling is planned for 2020-2021. More information about public water PFAS sampling is available on MDH’s website.
In 2013-2015, all city water systems serving over 10,000 people and randomly selected smaller systems were sampled as part of the EPA’s Unregulated Contaminant Monitoring Rule program. This sampling detected PFAS in Bemidji’s city water supply. MPCA and MDH have been working with Bemidji to address this. Since 2008, MDH has sampled city water wells throughout the state.