Addressing PFAS: What Wisconsin Engineers Need to Know
Per- and polyfluoroalkyl substances (PFAS) are an expansive group of man-made chemicals found in countless manufactured goods including clothing, non-stick cookware, food packaging, and more. As local governments and communities across Wisconsin become more aware of the PFAS chemicals in their water sources, more questions are asked on the effects of the chemicals on our bodies and how to effectively remove the chemical from our water.
On October 28, 2022 the ICS Group featured a webinar with manufacturing partner BioLargo. BioLargo manufactures the Aqueous Electrostatic Concentrator (AEC), an innovative technology that removes PFAS in water, wastewater, and is used in groundwater remediation. Our guest speaker Tonya Chandler, Director of Strategic Marketing and Business Development at BioLargo provided an hour of information on PFAS, federal and state regulations, analyzing and comparing PFAS removal technology, and an overview of the new PFAS removal technology offered from BioLargo.
Information about PFAS is changing daily. Tonya stated "To keep up with the information really gets crazy; combing through data continuously, both federally and locally. I live in La Crosse, and what is happening in the state is close to my heart."
What is PFAS?
Most engineers and wastewater operators know that PFAS is per- and polyfluoroalkyl substances. "There are also PFOA, PFOS, GENX compounds– but what we need to talk about is the long-chain vs. short-chain substances and the amount of carbon bonds that the substance has." In an article from Waste360, PFAS can vary in length between four and twelve molecules. 'Long-chain' PFAS compounds are typically defined based on having six or more carbons while 'short chain' compounds usually consist of seven carbons or less depending on the chemical make-up. There is an overlap between six to eight carbons to differentiate between long and short-chain PFAS compounds depending on the overall composition. Why do the length of carbon bonds matter in PFAS? Because the Carbon-Flourine (C-F) bond strength determines if the PFAS can be broken down, destroyed, how they affect our environment and bodies.
In this webinar, Tonya shared "The bonds we really need to look at is the polymers and non-polymers. PFOA (also known as C8) was used in manufacturing of Teflon, it’s where the long-chain carbon bonds came into the Teflon process. Long-chain bonds are more dangerous and are officially banned around globe. Unfortunately, banning of long-chains didn’t happen in United States. Our government just asked the companies to stop using them, but some continued to use them in manufacturing processes. Genx was short-chain replacement for C8 Teflon combination, PFBS was short-chain replacement for PFOS. Short-chains are known to be more mobile in soil and water. They move quickly because they are not as polar; but they don’t break down in the environment any faster. When regulators state four PFAS compounds are being looked at - it is actually six because there are two different version of PFBS and GENX."
History of PFAS
PFAS isn't a new chemical. Unfortunately, the majority of us are just hearing about it for the first time. According to Tonya's research "The first PFAS was developed by accident by 1938. When PFAS was commercialized by Dupont, the C8 was put into Teflon in 1945. That plant was built in West Virginia and six months after it was put up, female workers were taken off the production line because of known risk of birth defects. In 1951, things started heating up at the plant and 1956 they got first external report that showed PFAS chemicals built up in livers and was known to bind to blood proteins. In 1952, 3M created Scotch Guard and other products which used PFAS chemicals. In 1998, the EPA was alerted by external research how bad this (PFAS) was in the environment. In the year 2000, an article stated 3M promised to the EPA they were going to pull all of these chemicals willingly from their products, but never did anything about it."
"In 2001, Congress passed first PFAS action act and the bill still hasn’t fully passed. It is still sitting in Senate. As we all know, advisories and such have taken place. Recently, we saw the EPA has published the proposed rule for Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). CERCLA helps with cleanup efforts for chemicals and the EPA went after this approach first. Resource Conservation and Recovery Act (RCRA) will likely become active after CERCLA. In October, the EPA announced they will initiate RCRA, Appendix 8, as a hazardous constituent."
CERCLA and RCRA: What is Next for PFAS
It is good to remember that RCRA applies to active sites and CERCLA applies to non-active sites. According to Tonya's research, "These acts essentially force active sites to pay attention to how they are treating their contamination, so they don’t become a superfund site. Once PFAS is listed as hazardous constituent, there will need to be a cradle to grave solution. What this means is there will be special handling requirements, storage, treatment and disposal for the PFAS chemicals. CERCLA means polluters have to pay. If polluter cannot be identified, the super fund will pay for the clean-up. It is important to know that CERCLA is timeless and retroactive. By getting CERCLA in place, the EPA can go back to closed sites and make people clean up the contamination. For example, in the state of Florida, it doesn’t matter if you owned the site previously when the contamination occurred. The new property owner can be asked to clean up the contamination now. In April 2022, the EPA started pushing CERCLA forward and in June 2022 the health advisories came out for PFOS and PFOA."
"When the EPA publishes the CERCLA rules, the last published statement provided an example of categories that will be impacted by the rules. Wastewater facilities and landfills will be required to comply with these new rules. Both wastewater facilities and landfills are looking for exemptions and the EPA is stating they are not giving exemptions; but these organizations won’t be active targets. Without something in writing from the EPA, who knows how far the exemptions would get. Every landfill may be classified as super fund site because of the amount of PFAS they already contain. With the possibility of new rule making, new recording, anybody or any business that is known to release one pound of PFAS has to report it. Any PFAS contaminated soil, carbon, all of this will be treated as hazardous substances. This means that landfills may have to test incoming products for PFAS. If you have PFOA or PFOS substances you want to dispose of, they may not be accepted in landfill anymore. When this really becomes problem is the incineration of PFOS. We are going to see limited incineration possibilities. The EPA already released another monitoring program for emissions for PFAS and there is more is coming from what I hear. This will be part of clean air act, similar to dioxane and CFC. You will probably see incineration come back around but not yet."
New EPA Health Advisories, NPDES Permitting
In recent announcements from EPA, new health advisory limits were detailed. According to the announcement the EPA was suggesting health advisory limits .0004 ppt for PFOA, 0.02 ppt for PFOS in drinking water. Tonya reiterated "These low limits are insanity. But, by setting levels low, when the EPA does safe drinking water act regulations, they will typically go to the lowest possible measurement level. On the other hand, the regulatory side needs to make sure that levels are attainable through laboratory testing."
In April, the EPA announced they were going to include PFAS testing into NPDES permitting. "They have already pushed forward the rules and the Clean Water Act is coming. If the EPA can remove PFAS from drinking water and out of wastewater, then they believe can break the cycle of PFAS in our water. Looking at new EPA Draft Method 1621, which is the "Screening Method for the Determination of Adsorbable Organic Fluorine (AOF) in Aqueous Matrices by Combustion Ion Chromatography (CIC)." If you have hospitals or other sites that have pharmaceuticals in their wastewater, that would have fluorine impacts and they will show up in organofluorine sample methods. Every sample will likely show up with PFAS.
18 states have no PFAS regulations, 11 states have advisories, 21 states have passed formal regulations
Tonya shared, "As of August 1, 2022, the new PFAS administrative rules took effect in Wisconsin for drinking water, surface water, and sets regulations for fire-fighting foam which contains PFAS. PFAS in groundwater is not included in the regulations, however Govenor Evers is pushing for groundwater rules. As of right now, the standard is 8 parts per trillion in surface waters for PFOS and 20 ppt for PFOA in surface water. The Wisconsin Department of Natural Resources (DNR) is requiring testing from all wastewater facilities to make sure they are meeting the standard for all chemicals. It is apparent that PFAS won’t take long to build up in surface water from wastewater discharge."
"Another PFAS standard in Wisconsin comes from the Department of Health Services. If the drinking water in a community receives high test results for PFAS in relation to the DHS standard, your community is required to notify the residents. Although Wisconsin does not have a definitive PFAS standard on groundwater or drinking water, your community will still have to notify residents of PFAS contamination. It gets convoluted as you go along since the standards and requirements are changing daily."
Sampling for PFAS: Tips to Keep in Mind
Remember that PFAS is found in firefighting foam, but it is also found in a lot of other items - such as waterproof clothing, cosmetics, sunscreen, personal care products, food wrappers, and pesticides. "When you talk about PFAS contamination sources and PFAS sampling, all of these things additional items come into play. Consider what happens when you wear the wrong gloves, have applied sunscreen, or any other item that could have possibly contaminated the environment can impact your sample results. PFAS sheds at small levels when you are talking parts per trillion. Simply having lotion on your hands can send your sample over the top for PFAS."
"It is good to keep in mind to not use sampling materials that contain Polytetrafluoroethylene (PTFE) or Polyvinylidene fluoride or polyvinylidene difluoride (PVDF). If you are using hosing or tubing, you need to know what they are made of and what is coating the inside of the hose. Seals and gaskets are made of polychlorotrifluoroethylene (PCTFE). Pipe lining is made of fluorinated ethylene propylene (FEP)."
It is best to stay away from low-density polyethylene because certain low-density polyethylene will absorb PFAS. If the sample is not in direct contact with PFAS, it will be okay. For example: Ziploc bags are okay to use in the process (if they don’t come in contact with sample.) What you want to use for your sampling is high-density polyethylene. PFAS is known to absorb to glass so you can’t store water samples for an extended period of time. Good tips to follow when sampling for PFAS:
Use powderless nitrile gloves
Wear well laundered synthetic cotton clothing
Do not use fabric softeners because they have PFAS
Remember, PFAS migrate to air water interfaces so churning water with foam will have high concentrations in the foam and surface
Do not take water at the bottom of sample because of binding and sinking
PFAS concentrations may fluctuate in pumping cycle
Check for PFAS in water-proof notebooks, sticky notes, all of these things can affect PFAS sample
You don’t want a sample with a high result due to wrong gloves, sunscreen, anything like that you run across and contaminated sample
Choosing the Best PFAS Treatment Technology
Tonya shared her knowledge of the technologies available to treat PFAS contamination. "We all know about ion exchange, absorbent medias, membrane medias, and new technology such as oxidation reduction and others. All of these technologies that treat PFAS, engineers need to consider cost vs. efficacy." You should consider the following questions before selecting a technology:
What is the source of the water and other constituents that are in the water?
Besides considering what other constituents are in the water, you need to analyze what utilities are available to power your equipment effectively.
What resources or funding options are available for the project?
Will the technology have a biproduct?
What are the consumables? With new CERCLA and RCRA standards, you will need to look at disposing of consumables
Engineers, community leaders, and municipalities can gravitate to a known technology, but there are a number of things to consider when picking PFAS treatment technology.
"If you have more short-chain PFAS compounds than long-chains, you really need to look past the traditional technologies. Traditional PFAS removal technologies will not take short-chain PFAS compounds out very efficiently. If you are considering ion exchange technology, you need to consider total organic carbon (TOC) in the source water. Short-chain PFAS compounds go through the ion exchange media, and they are not bonding as well as the long-chain PFAS compounds to the ion exchange media. Since they are not binding, the compounds are pushed off and slough off into the effluent water. Power and utilities are another factor to consider. Super critical oxidation treatment or plasma treatment requires a lot of power. If you don’t have a power plant next to facility this may cause a problem. Companies that pilot this technology may experience great results on the scaled-down pilot level, but you need to consider what happens when you scale them up."
Tonya compared and explained PFAS technology that is available to businesses and municipalities:
Granular Activated Carbon (GAC) – contaminated water has a long contact time, but the carbon media cannot be regenerated. Because you cannot regenerate, this will make life difficult when you talk about CERCLA and RCRA. GAC is a good option for small system with small budget.
Ion Exchange – contaminated water has a shorter contact time, so it is not effective on small-chain PFAS compounds. Ion exchange also has a hard time removing PFBS and PFBA (because they are not as polar of a molecule, cannot connect to the media). Ion exchange is good for small systems or projects with a small budget. As the PFAS standard gets closer to zero, ion exchange systems are a less acceptable option. You may need to exchange the media out much faster because you cannot regenerate the media on site.
Membrane Filtration – this technology is good for facilities already using reverse osmosis (RO) systems. The membranes provide 80% to 90% removal on PFAS and can be coupled with another technology to remove the rest of the PFAS. You can also treat concentrated stream and that becomes an issue especially with wastewater. It is best to look at some of the newer technologies for wastewater plants.
New options for PFAS removal and technology are being developed, piloted and commercialized right now. "The fluorine carbon bond is the strongest in organic chemistry and it is a hard prospect for innovation. You can’t destroy it so what do we create as part of the innovation? Right now, there is a lot of the innovation being invested in electro chemical, plasma, supercritical water oxidation, and bioremediation technologies. Work is being done in Wisconsin on bioremediation with electrocuting the ground, but we are still waiting for more data to come out on this because not a lot of research has been done," commented Tonya.
Who is BioLargo and how are they innovating PFAS technology? Tonya shared, "BioLargo is a group of engineers who are known as trusted industry veterans and have compiled significant scientific research on PFAS. The BioLargo team started with a hypothesis that we wanted to remove PFAS compounds from water, so how can we accomplish this? Our team looked at existing technology, but few were going after SBIR grant with EPA. The BioLargo engineers sat down to draw up a new technology and Aqueous Electrostatic Concentrator (AEC) was born. This technology uses the polarity of PFAS against it. The engineers hypothesized if they created chambers with series of electrodes and membranes, they could remove PFAS from the water and create a concentrated stream. The main goal was to produce a stream that met the standards and figured if we engineered a system with multiple stages, then we would have potential to produce deionized water. The PFAS removal would remain a low energy process, so the cost of removal would remain affordable for the customer."
"What the BioLargo engineers found was not what they expected. After the first system was manufactured, the initial testing concluded that no concentrated waste stream existed. Ultimately, the engineers were not finding PFAS in the anode stream. The Aqueous Electrostatic Concentrator was able to remove 99% of PFAS with single pass through the system. Another benefit was noted with the PFAS removal. Desalination occurred as well, even with low energy consumption which resulted in a low operational cost. On average, the BioLargo Aqueous Electrostatic Concentrator costs approximately 30 cents per 1000 gallons of water. What we learned was we were ripping PFAS out of the water and it was instantaneously fusing to the membrane. Once it fused to membrane, the PFAS fused to itself. All of the PFAS stayed on the membrane, all before the membrane was spent."
You may ask how the system works? The Aqueous Electrostatic Concentrator runs an electric current through our specialized system to the membranes. Tonya commented, "In our testing, we were able to remove most of PFAS in single pass. We can run passes through the system until we get 100% removal. The Aqueous Electrostatic Concentrator system has extremely low energy requirements, no moving parts, and we are able to tailor the water on the backside. The technology can lower chloride levels, depending on how much water we blend back in to make it drinkable. The system is high capacity, at 70 ppt on PFOA, a 10,000 gpm unit would operate 3.8 million hours to take membranes to full capacity. The length of membrane life will depend on how low the PFAS level will have to go. What happens when the membranes are at full capacity? The BioLargo offers easy disposal options because we run a service exchange. We dispose of the spent membranes as service."
The Advantages and Disadvantages of the BioLargo Aqueous Electrostatic Concentrator
"We know we are new process, but we believe in what we are doing."
BioLargo is capable of doing design, construction, contract building, and maintenance on the AEC systems
Our engineers have 30 years of experience designing and working on these systems
Full, comprehensive PFAS testing program is offered through BioLargo. Multi-phase approach to ensure proof of concept and peace of mind
BioLargo offers bench scale pilot testing in their “water lab”. We ask the customer for fee to send 10 gallons of water, we run the water through the AEC system and take lab samples of water and lab samples of chambers and water coming out. We will run at first, third and fifth pass if necessary to achieve results
Once the testing is completed, the customer will receive a report of how exactly how the system will work
Once we are past the bench scale piloting, we go to onsite piloting of the AEC unit
The BioLargo AEC pilot unit runs two to three gpm in field. Onsite piloting will receive discount if you have completed the bench testing. If you pilot the AEC and decide to go to a full-scale installation, BioLargo will offer a credit
We will offer process guarantee if you go from bench testing to full scale installation. The process guarantee is that the AEC will remove PFAS as long as incoming water does not change (within certain percentage)
We offer services exchange program to make sure the AEC system keeps running as it should
We can measure PFAS removal in real time. The BioLargo team has discovered a correlation between the removal of PFAS and salts in the unit. When conductivity rises, we need to do cleaning on the system to maintain consistency.
The size of the system is similar to a GAC system, but we don’t need to be skidded
We can line walls, drop the AEC into a pit that not used anymore, stack them on top of each other to create space. Only requirement is if there is maintenance room around them, we are flexible on layout
It is good to know that the GAC removal number is single pass, no lead lag in that number
If we know the AEC system will not work for the customer, we will run the water samples through GAC and ion exchange (if that is necessary) to prove results
BioLargo team just signed their first commercial remediation project in Midwest
The AEC will work for both water and wastewater processes, as well as for groundwater remediation
This is new PFAS removal technology
We are now working on getting the information set up for the first commercial system in the field. Noted - BioLargo currently has a system in our Tennessee facility. This system has been running for long time with no issues
The Aqueous Electrostatic Concentrator still has consumable parts, and we are working on efficient removal and destruction. We want to make sure that we are destroying the PFAS effectively without creating anything worse
The operational costs are based on influence by other constituents in the water
The more salt content in the water, the more energy is needed to run the process
BioLargo does require a service contract for membrane disposal and the technology will need electricity
To learn more about the BioLargo Aqueous Electrostatic Concentrator for PFAS removal, please contact Paul Nygaard at the ICS Group. Our team would work with the BioLargo team to coordinate an in-person or virtual meeting, product demonstration or pilot. Visit www.bestpfastreatment.com to gather more information on case studies and the AEC system for PFAS removal.
Access to the full webinar can be found on the ICS Group YouTube channel. Please click here to watch the PFAS recording.