How AqueoUS Vets Scaled PFAS Removal to 120+ Projects

AqueoUS Vets, the PFAS pure-play

Founded in California in 2015, AqueoUS Vets is what Mirka Wilderer, its CEO at the time of our 2025 conversation, calls a pure player: it removes PFAS and other contaminants of emerging concern from drinking water for municipalities and utilities, and it sells nothing else. The name itself is a tell, Aqua plus US for the American focus, and "Vets" for the water veterans who started it. Where most of the field carries a broad catalogue, AqueoUS Vets carries one hammer and looks for the right nails.

Now, "we only do one thing" is easy to say and hard to make pay. What makes it work is a set of four design principles Mirka walks through on the show: optimize the media for the actual contaminant on the actual site, control corrosion with the right materials, design for low head loss so you spend less energy pushing water, and make the systems easy to operate and maintain. Add it up and you get the promise that matters to a utility budget, low capital cost and low running cost, from a company that has nothing else to sell you. That is the whole pitch, and as you will see, it is also the whole reason a private-equity impact fund came knocking. what PFAS actually are and why they are so hard to remove

Ion exchange or carbon: how do you actually remove PFAS, and at what cost?

If you ask the EPA how you take PFAS out of water, you get four "best available technologies": granular activated carbon (GAC, basically a very thirsty charcoal that the molecules stick to), anion exchange (IX, a resin that swaps the contaminant for a harmless ion), reverse osmosis, and nanofiltration. AqueoUS Vets plays in the first two, carbon and ion exchange, and it stays deliberately neutral about which one a site gets.

That neutrality is pure economics. Carbon is cheaper to buy but you change it out more often. Ion-exchange resin costs more up front, but here is where it gets interesting, so let me walk the numbers. A resin bed will treat roughly ten to twenty times the volume of water that a carbon bed handles before it is spent , which means far fewer change-outs, far less downtime, and it tends to hit the very low limits more reliably. Stretch that across a plant's life and the picture is genuinely wide: independent life-cycle reviews put the running cost of PFAS treatment anywhere from about three cents to twenty-eight dollars per cubic metre of water, depending on the source water and the technology. So "which media" really comes down to a site's water and a utility's budget, which is exactly why selling both, and picking per site, is the smart commercial position.

Why does the market pay to remove PFAS, not destroy it?

Here is the contrarian core of this story, and it is an economics argument, not a chemistry one. Removing PFAS does not actually get rid of PFAS. It "just" moves them, off the water and onto spent carbon or resin that now has to be hauled away and, eventually, dealt with. The only way to truly end a PFAS molecule may be to break it, and breaking that very long carbon bond is hard, energy-hungry, and expensive. I dug into one such destruction route in my newsletter, asking whether anyone can really destroy PFAS for ten cents a gallon, and the honest answer is "not yet, not at the price the market wants." can they really destroy PFAS for ten cents a gallon

So why does almost all the money still flow to removal? Because the rule only asks for removal. A utility is told to get PFAS below a legal limit in the water it delivers, and once it has done that, it has complied. Nobody hands it a second budget to then destroy what it captured, and no operator volunteers to pay that premium when "out of the water" already satisfies the regulator. My own view, which I have laid out before, is that destruction is where this has to end up, otherwise we are just kicking the can. why I lean toward destroying PFAS, not just removing it But realistically, someone has to pay for that can to be crushed, and until a rule mandates or rewards destruction, removal is simply the rational purchase. AqueoUS Vets understood this and built for the world as it is, staying, in Mirka's words, destruction-agnostic, even concentrating PFAS with its own foam-fractionation system so that whatever destruction step does eventually arrive has less to chew on.

The 120-project track record, and the largest plant of its kind

The track record is the moat, and it is unusually concrete. AqueoUS Vets numbers its projects, and on the show Mirka puts the count plainly: they are "currently executing projects in the 120th number," and "north of 100" installed across the country, from Redding in California to Stuart in Florida to a first job in Rhode Island. The reference project that put them there is the one in Yorba Linda, where they supplied the 27 ion-exchange systems behind what the water districts call the nation's largest ion-exchange PFAS treatment plant, a facility with 22 resin vessels and a 25-MGD booster station, MGD being million gallons a day, running around 19 of them in practice. They did not own that plant, the utilities do, but they built the part that takes the PFAS out.

What makes 120-plus believable rather than a slide is the boring part, speed. Because the systems are pre-fitted at the factory before they ship, an install is measured in hours, not the weeks a built-on-site job would take, and for a utility staring down a compliance deadline, that is the difference between making it and missing it. where these treatment trains sit in the bigger picture of membranes and media

Why did Bain Capital's impact fund bet on a PFAS pure-play?

This is the part that turns an engineering story into an investor one. In 2022, Bain Capital Double Impact, the firm's dedicated impact fund, took a majority stake in AqueoUS Vets. What makes that notable is not just the name on the cheque, but that, as Mirka tells it, AqueoUS Vets was the first water company, and the first manufacturing company, in that fund. The logic is clean once you say it out loud: an impact fund needs measurable good, and a company whose entire output is "litres of drinking water cleared of a regulated toxin" is about as measurable as impact gets. It also rides a capital wave that is getting harder to ignore. where water-tech capital is actually flowing

Then, in 2023, the bought company did some buying of its own. AqueoUS Vets acquired Dixie Tank, a tank manufacturer, to plant a factory on the East Coast and bring the steel into its own supply chain. For a newcomer to private equity, this is the textbook "bolt-on," a small, strategic acquisition (the tank-maker) tucked under a platform company (AqueoUS Vets) to fix a specific problem, here the lead times and shipping costs of moving big steel vessels across the country. Vertical integration, in plain terms, owning more of your own supply chain so a bottleneck cannot hold your growth hostage. I unpacked how private equity is rewiring water tech like this in a recent newsletter, because the pattern is everywhere now. the PE strategies reshaping water tech

What is the EPA PFAS limit, and what is it doing to the market?

All of this only pays because demand now has a date on it. In April 2024 the EPA finalized a national limit of 4 parts per trillion for the two best-known PFAS, PFOA and PFOS, parts per trillion being roughly a single drop in twenty Olympic pools. Every system that tests over that line suddenly needs a removal plan it did not have the year before. That is the whole market, conjured by a number.

She called it, almost to the letter. By 2026 the EPA had kept the PFOA and PFOS limits exactly where they were, at 4 parts per trillion, an MCL being the maximum contaminant level, the legal ceiling a utility's water has to stay under, while moving to rescind the limits it had set on four other PFAS and pushing the compliance deadline out two years, to 2031. A revision, not an elimination, just as she said. And notice what that limit actually mandates, getting the two compounds out of the water, full stop. It says nothing about then destroying them. Which is the whole reason the removal market is booming while the destruction market waits for a rule of its own, and why a company that does removal, cheaply and fast, is exactly the kind of company a regulation like this calls into being. the invisible threat the regulation is chasing

FAQ

What does AqueoUS Vets do?

AqueoUS Vets is a California company, founded in 2015, that removes PFAS and other contaminants of emerging concern from municipal and utility drinking water, using granular activated carbon and ion-exchange resin systems. It is a pure player, meaning PFAS-style removal is the only thing it sells.

What is the difference between ion exchange and GAC for PFAS?

Granular activated carbon (GAC) is cheaper to buy but is spent faster; ion-exchange (IX) resin costs more up front but treats roughly 10 to 20 times the volume of water before change-out and tends to hit very low limits more reliably. The right choice depends on the source water and the budget, which is why AqueoUS Vets offers both.

How much does PFAS treatment cost?

It varies widely with the water and the technology. Independent 2025 life-cycle reviews put operating costs from about 3 cents to 28 dollars per cubic metre treated, with capital costs from roughly 1 to 51 cents per cubic metre. Ion exchange costs more up front than carbon, but its longer runs between change-outs pull the whole-life cost back down.

What is the largest PFAS treatment plant in the US?

The Yorba Linda facility in California is described by its water districts as the nation's largest ion-exchange PFAS treatment plant, with 22 resin vessels and a 25-MGD booster station. AqueoUS Vets supplied the 27 ion-exchange systems; the plant is owned by the local water districts.

Who owns AqueoUS Vets?

Bain Capital Double Impact, Bain Capital's impact fund, took a majority stake in 2022. AqueoUS Vets was the fund's first water company and first manufacturing company.

What is the EPA PFAS limit?

In April 2024 the EPA set a maximum contaminant level of 4 parts per trillion for PFOA and PFOS, with monitoring by 2027 and compliance by 2029. A 2025 to 2026 reconsideration kept those two limits, moved to rescind the limits on four other PFAS, and proposed extending compliance to 2031.

Is it better to remove or destroy PFAS?

Destroying PFAS may be the only way to truly eliminate them; removal concentrates them onto spent media that still has to be managed. But destruction costs more, and current rules only require removal, so the market overwhelmingly pays for removal today. Destruction scales when a regulation mandates or rewards it.

For all the talk of compliance deadlines, the line from Mirka that stuck with me is that AqueoUS Vets actually ran a purpose exercise with a hundred-year horizon, even though today's mission is simply taking PFAS out of water. The open question was never really the chemistry, because destruction is probably where this has to end up; the real one is whether a rule will ever make someone pay for it. Until then, removal stays the rational bet, and AqueoUS Vets is built precisely for that reality, taking the problem out of the water now and staying patient about the day the destruction money finally arrives. Give the full conversation a listen below, and tell me in the comments which side of that bet you would build.

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Sources

1. EPA, "Reducing PFAS in Drinking Water with Treatment Technologies" (2024). link
2. AWWA Journal, "The Cost to Remove PFAS: A Review of US Water Treatment Plants" (May 2025). link
3. Life-cycle review of PFAS treatment technologies, ScienceDirect (2025). link
4. Yorba Linda / Orange County Water District, "Nation's Largest Ion Exchange PFAS Treatment Facility" (ACWA, Dec 2021). link
5. Bain Capital Double Impact, AqueoUS Vets portfolio. link
6. "Bain Capital-backed AqueoUS Vets buys manufacturer Dixie Tank Company" (PE Hub, 2023). link
7. EPA, PFAS National Primary Drinking Water Regulation (April 2024). link
8. EPA, "EPA Announces It Will Keep Maximum Contaminant Levels for PFOA, PFOS" + the 2026 compliance-extension proposal. link