PFAS Pilots: Success Depends on Advance Planning

In 2024, maximum contaminant levels (MCLs) for six common PFAS were finalized by U.S. EPA drinking water regulations. These regulations started the clock on a five-year compliance timeline that have U.S. utilities actively procuring new or upgraded PFAS treatment systems. 
By June 2029, public water systems in the U.S. must not exceed these MCLs: 4 ppt for PFOA and PFOS, 10 ppt for PFHxS, PFNA and HFPO-DA, and a maximum Hazard Index that applies to PFAS mixtures containing two or more of PFHxS, PFNA, HFPO-DA and PFBS. Read more about the regulations here.

Why is a PFAS pilot worth the time and money?

For most facilities, technology to achieve these MCLs will be a significant investment. Piloting can reduce financial risk, save a plant millions of dollars over the life of the equipment and provide a tremendous return on investment. 

Pilots can reveal problems that occur infrequently but can still cause major headaches. PFAS pilots are especially helpful because not all technologies can remove both short-chain and long-chain PFAS equally well, and piloting can keep facilities from wasting money on the wrong technology. 

A pilot provides the most accurate prediction of media life. A bad technological match can result in frequent media changeouts (and disposal costs), which will drive up operational expenses. 

What are the essential parts of a PFAS pilot?

The key to successful piloting is advanced preparation in seven key areas. 

CONTAMINANT TARGETING
Contaminants of interest include the ones you want to treat directly and those that may influence your mitigation approach due to chemistry, emerging regulations or other factors. While your goal may be to treat regulated PFAS, testing may reveal non-regulated PFAS compounds or other contaminants that would affect the performance of a PFAS treatment system. If this happens, you will need to decide how to manage those contaminants. 
A one-time water analysis is essential but only a snapshot that may not reflect the impact of seasonal and/or cyclical fluctuations in water chemistry or operating conditions. To completely understand a plant’s specific water over time, consult your team and facility data for known occasional variations in water quality due to seasonality, nearby industrial activity, extreme weather and other aberrations. 

CHOOSING A PILOT PARTNER
Your pilot partner may be an equipment supplier, if you already know what equipment you want to pilot, or it could be a consulting engineer if you have one already or need more guidance. Some organizations have in-house piloting capabilities. Your partner will help design the pilot parameters, evaluate water quality, specify the technology and outline the process. 
Select a partner with experience in piloting and treating your target contaminant(s). For treatment of regulated PFAS, you will likely pilot a granular activated carbon (GAC) and/or ion exchange (IX) resin system, so choose a partner with competence using these technologies. 

PILOT SCOPE AND COST 
A good scope of work keeps a project on track and defines who is responsible for what activities from start to finish. Ideally written as a contract, the scope should include detailed responsibilities, budgets and timelines for the owner, engineer and equipment supplier. The scope should include small items like costs and insurance coverage for equipment delivery and return, which can surprisingly amount to significant expense. Also, be sure to define who owns the data in your final report (see below) and what rights exist for publication among the participating entities. 

PILOT PLAN
Based on the complexity of your application, a pilot plan will determine if you first need a bench test or if you can start with field-based piloting. Bench tests can be conducted onsite, at the equipment supplier’s site or at a third party site. 
Your plan should specify where, how and how often water samples will be collected to get the most representative sample of the water that will be treated by the full-scale installation. 

PROCESS CONTROL DESIGN
A PFAS pilot process control plan ensures that your pilot closely simulates a full-scale installation. Process design and oversight must be expertly managed to achieve meaningful results – another reason to use an experienced partner.  This item includes describing how you will monitor the pilot (grab samples or continual online monitoring), determining the data you want and where it will originate (such as plant data, online analyzers, third-party accredited labs and/or operator checklists), and how the data will be stored for later analysis and reporting.

HEALTH, SAFETY AND ENVIRONMENTAL CONSIDERATIONS
Onsite pilots are subject to all the same health, safety and environmental requirements as full scale installations. Determine what personal protective equipment operators will need, where treated water and treated media backwash will go and how spent media will be handled. This step also includes the storage and handling of chemicals and reagents and if there is a need for secondary containment in case of a treated water leak or chemical spill. 

DETAILED FINAL EVALUATION
The PFAS piloting partner should always deliver a final report at the conclusion of the pilot. This report should include a data-driven analysis of results with design scaling factors, considerations and assumptions, and objective recommendations on next steps for the water system. 

How long should a pilot be?

A pilot of three to six months can provide some data if time is limited. The ideal pilot length is 12-18 months or long enough to fully exhaust one lifecycle of media fill and capture a year’s worth of changes in temperature, turbidity, water quality and other factors. This reduces the risk of investing in new technology only to learn that it cannot handle an infrequent but predictable contamination spike.

Why work with De Nora?

De Nora deeply understands water treatment and how to treat PFAS, with tens of thousands of installations globally over decades of experience and particular expertise in PFAS pilots and PFAS treatment. 
De Nora pilots include:

• Dual small-scale column pilots for testing/comparing the PFAS remediation efficacy of two medias such as two IX, two GAC or one of each
• Quad small-scale column pilots for testing or comparing even more options and/or combinations
• Containerized pilots for treating up to 35gpm in lead-lag configuration or up to 70gpm in parallel operation.

De Nora’s PFAS pilot treatment offerings are tailored systems designed to help your organization reduce PFAS  for a wide range of flow and treatment needs.