MCLs and Water Quality: Take Action with Your PFAS Detection Results


EPA’s Maximum Contaminant Limits (MCLs) have guided the Safe Drinking Water Act (SWDA) for nearly 50 years to maintain healthy drinking water standards across the US. These MCLs lead the way for American water utilities to manage established and previously unknown contaminants to prevent them from affecting their community and neighboring communities’ health, now and in the future. They ensure a range of pollutants, such as arsenic, e. Coli, and benzene, stay within a reasonable threshold for American drinking water to stay trustworthy and safe to consume. However, these MCLs also create a demand for new water treatment processes and standard operating procedures. And the most recent MCLs proposed by the US EPA have the potential to do the same.

Among the proposed contaminant MCLs listed, six of them are PFAS chemicals. If these six PFAS are added to the US EPA’s National Primary Drinking Water Regulations (NPDWR), water utilities nationwide will be required to monitor PFAS, include PFAS levels in Consumer Confidence Reports, and treat source water containing PFAS concentrations higher than the proposed MCLs.  

The new MCLs will likely be solidified by the end of 2023 and, if approved, will go into effect at the end of 2026. With a three-year window to meet the EPA’s new MCLs, American water utilities will be required to invest in lab testing, consider treatment process modifications, and potentially delay planned capital projects and improvements to fund these unforeseen water plant upgrades. The EPA estimates that American water utilities will need to spend $772M per year to comply with the proposed PFAS MCLs, while private entities predict the cost will be higher.

Most state health departments do not currently have MCLs for PFAS chemicals. But if the proposed EPA MCLs are approved, PFAS will become a national requirement for most American water facilities. Given the gravity of PFAS’ health effects, your facility would benefit from testing your source water for PFAS ahead of time. Even without state or national MCLs in place, big polluters can be held accountable for your water plant’s PFAS treatment.

MCLs and Water Quality Regulations

Since going into effect in 1974, the SDWA has dictated how America keeps its citizens' drinking water safe. EPA periodically modifies the Act with new MCLs to further address emerging and known contaminants. To maintain compliance, water utilities design their treatments and procedures to meet the SDWA’s MCLs.

Updated MCLs precipitate intensive construction projects that require capital, consulting engineers, and continued operations during construction. These projects are expensive, and the current inflation rate is already pushing public works budgets to their limit. In the American Water Works Association's State of The Water Industry 2023 report, 1 in 5 water utilities reported being "extremely concerned regarding their ability to comply with the PFAS health advisory."

By following federal and state MCLs, our water utilities impede the impacts of water contamination on public health. These impacts are seen over different time spans and severities and have inconsistent implications for various populations. For example, lead disproportionately affects pregnant women and young children, stunting their IQs. E. coli can cause acute abdominal pain and even kidney failure with prolonged exposure. PFAS are found to weaken immune systems and vaccine response, increase cancer risk, and elevate cholesterol levels, which is why they are being considered in the latest round of MCLs.

Most Effective PFAS Detection Methods

Monitoring and detection are the first steps to complying with the proposed PFAS MCLs. EPA lists three approved methods for utilities and private laboratories to detect 29 unique PFAS variants, including the six to be added to the NPDWR. Even in states without PFAS MCLs, forward-looking water utilities can use these methods, named Methods 533, 537.1, and 537, to clarify how the proposed MCLs could affect their water system's operations. Note that these methods sample finished drinking water and can also be used to monitor the Unregulated Contaminant Monitoring Regulations 5 (UCMR) PFAS chemicals.

EPA developed, validated, and published all three analysis methods. They require solid phase extraction and spectrometry to analyze water samples but use different reagents. Based on your lab's resources, one of these methods may be more feasible than the others. Review these methods with a lab professional to determine the most effective way to test your finished water's PFAS concentrations. While they may be new to your staff or lab, EPA’s methods provide step-by-step instructions for your utility to produce verifiable results and understand PFAS MCLs' implications on your water system.

How to Interpret PFAS Test Results

After your facility runs its chosen PFAS detection method and receives concentration results, it’s time to understand the implications. Suppose your finished water samples contain PFOA and PFOS levels over four parts per trillion (ppt) or reach a Hazard Index composite over 1 for PFNA, PFHxS, PFBS, and GenX chemicals. In that case, your facility will be responsible for removing these PFAS from your water source if the new MCLs pass. Your utility will also have to consider the MCL’s effect on consumer trust, capital planning, and funding of PFAS treatment.

However, regardless of state and federal regulations, your water utility could be entitled to contamination compensation. Employing the EPA’s approved PFAS analysis methods, facilities have grounds for pursuing litigation to recover cleanup costs from big industry polluters and using that money to pay for new treatment technologies without burdening ratepayers.

Detection without MCL Regulations

Those operating water treatment in states without PFAS MCLs may feel they have ample time or little cause for concern. While they will not be required to treat PFAS until the newest EPA MCLs are approved, consider why acting now may be advantageous.

  1. Public Opinion: Even when water providers are not required to treat PFAS, local consumers may want them to manage PFAS as awareness spreads. Proactively holding polluters responsible for the situation shows your utility takes the issue seriously, improves consumer confidence, and addresses public concerns early on.
  2. Clarity: As the new PFAS MCLs are approved, water facilities can be ahead of the curve by knowing their source water’s PFAS concentrations and appropriate treatment methods as others scramble to test, adjust their treatment trains, and find emergency funding.
  3. Time: By being proactive, your facility gains more time to find suitable PFAS compliance solutions and funding options that meet MCLs, whether State or Federal.
  4. Statute of Limitations: Facilities that want to remove PFAS contamination, regardless of location or regulations, can still sue industrial polluters to fund monitoring and water treatment upgrades. But water districts and utilities must act quickly. Depending on the state or territory, there may be a small window for your facility to receive compensation from those responsible for your water source’s PFAS contamination.

Discovering PFAS in your drinking water can be alarming. But there are routes to receiving compensation from industrial polluters regardless of state or federal MCLs. Your facility may be able to recover the cost of PFAS MCL compliance from local polluters. But the clock is ticking.

Taking Action

As water facilities face new contaminants, their MCLs, and pressures to deliver healthy, affordable drinking water, holding industrial polluters accountable can be a feasible way to meet EPA compliance and protect the health of their consumers.  

SL Environmental Law Group has a track record of fighting for water utilities dealing with contamination from big companies. By working with a firm with extensive experience in water contamination litigation, water utilities can meet PFAS MCLs without burdening their community with treatment costs.

Schedule a Free Consultation today.