While reducing pumping at specific wells with the highest measurements of the chemical solvent lowered levels of 1,4-dioxane going into Lake Mary homes to what is considered “safe” by both the EPA and the Florida Department of Health (DOH), former public works director, Bruce Paster, was concerned for the future. What if the levels of 1,4-dioxane increased again, and suddenly, residents and public health officials demanded a comprehensive solution for the 3 million gallons of drinking water pumping into the city daily?
For Lake Mary residents, the city blamed the companies liable for the crisis. The chemical plume originated at the Siemans-Stromberg hazardous waste site at 400 Rinehart Road, Seminole County, which, according to DOH paperwork, used chlorinated solvents until the early 1980s. Over the years, three companies were associated with the site—General Dynamics, MONI Holdings, and Siemens—all required to collectively pay for Lake Mary’s new water treatment plant.
This agreement gave Lake Mary a unique opportunity, according to Public Works Director Danielle Koury. Unlike most municipal water utilities forced to find the most practical solution at the lowest affordable cost, Lake Mary made a deal with the three responsible companies to create the best possible water treatment system that money could buy. The cost was roughly $40 million, according to Ms. Koury.
Instead of only using granulated activated carbon (GAC) to filter its groundwater contaminants—which is essentially high-grade charcoal—Lake Mary adopted an approach known as “advanced oxidation,” which completely “destroys” 1,4-dioxane by ripping the molecules to shreds, leaving no byproduct whatsoever, according to Ms. Koury.
She said the solution is ideal because “We are essentially destroying the chemical, not just removing it from the water that you’re drinking. So, like with reverse osmosis and carbon filters, the chemical is being absorbed into either a membrane or that carbon. What do you do with the membrane or the leftover? You’re removing the chemical; what do you do with the waste that is still present?”
Advanced oxidation combines the power of strong ultraviolet lights with the corrosive powers of hydrogen peroxide to create what’s known as a hydroxyl radical, a molecule with the capability of tearing apart certain chemicals and rendering them inert, such as 1,4-dioxane. The UV lights are similar to the ones used in air sanitation products but much stronger. While store-bought hydrogen peroxide’s strength is only 3 percent, the peroxide used by Lake Mary is 50 percent and nearly 17 times stronger.
For 1,4-dioxane, public health officials nationwide are facing similar issues to Lake Mary. The solvent was found in shallow groundwater in Waterworks Park in Ann Arbor, Michigan, in 2016 after it migrated from a plume that originated at the former Gelman Sciences property. While the chemical’s levels were not high enough to result in vapor exposure from running water indoors, some public health officials feared ramifications of long-term exposure to the solvent.
Officials found 1,4-dioxane in Pittsboro, North Carolina’s drinking water in 2021. Initial tests confirmed that levels of 1,4-dioxane were more than double the amount considered to be safe, according to officials. The town stopped drawing as much water from Haw River, which had high measurements of the chemical, in hopes that it would reduce the 1,4-dioxane to a safe threshold. Despite those attempts, the amount of 1,4-dioxane in the town’s water was slightly higher than what the EPA deems safe.
Lake Mary’s solution to its 1,4-dioxane groundwater contamination is comprehensive and advanced and could potentially destroy other common chemical contaminants such as vinyl chloride, according to Ms. Koury. However, every chemical exposed to advanced oxidation would need to be studied extensively first. And that will depend on every municipality’s water source, she said.
Ms. Koury pointed out the issue of different contaminants coming from water sources that could be adjacent. Other wells could contain bromide, which turns into a highly dangerous chemical known as bromate when exposed to advanced oxidation.
Dr. Steven J. Duranceau, Professor of Environmental Engineering at the University of Central Florida and Director of the Environmental Systems Engineering Institute, echoed these concerns. According to Dr. Duranceau, advanced oxidation not only presents issues when groundwater contains bromide but is not the only solution for removing 1,4-dioxane specifically.
He co-authored a paper on using a “nanofiltration membrane process” to remove the solvent from exposed groundwater, akin to a super-dense filter with a tiny micron count. However, according to Dr. Duranceau, GAC is also effective at removing 1,4-dioxane; it is not as comprehensive as advanced oxidation because there is waste when replacing the carbon that filters the chemical.
Many residents expressed frustrations with Lake Mary, even though Dr. Duranceau emphasizes that chemicals like 1,4-dioxane were previously unregulated by the EPA.
“If it was me that found out, I'd be thankful that Lake Mary went ahead above and beyond to protect their citizens through the public water system. You know, kudos to them for going and making an organization help them deal with a contamination issue that wasn’t even regulated,” he said.
Creating Safe Drinking Water
“You’re talking about a complex natural water system that has one or more contaminants in it because of industrialization,” Dr. Duranceau said.Sometimes, officials trace those contaminants to leaking gasoline tanks underneath old gas stations, which can release a chemical known as TCE into the surrounding groundwater. While water treatment plants can remove TCE through aeration techniques, just one ounce of gasoline is required to contaminate millions of gallons of water, according to Dr. Duranceau.
He said that water wells in Florida also test positive for chemicals like benzene and xylene. Some chemicals found in wells are regulated at low levels, and others are not. All regulated chemicals in drinking water are defined by the Safe Drinking Water Act.
“The drinking water laws, the United States Environmental Protection Agency’s Safe Drinking Water Act is the most complex, comprehensive legislation ever enacted by any society, in the history of the world, to protect people’s exposure in a public system to an involuntary exposure to contaminants in the water system,” Dr. Duranceau said.
For many municipalities faced with chemical contaminants in their groundwater, using activated carbon (GAC) is typically enough, as long as the carbon media is replaced as needed, Dr. Duranceau said. However, he noted a past public health crisis in Hawaii when countless residents bought GAC systems for their homes to rid their water of chlorine, which is an essential disinfectant in most public water systems.
According to Dr. Duranceau, many residents were not replacing the carbon in their GAC systems, which led to rampant bacterial growth within their home water filtration equipment. An “itchy water” outbreak resulted that residents blamed on their municipal water utility, when in fact, it was the residents doing it to themselves, he said.
Natural disasters can complicate public water safety as well.
After the August 2023 fires in Maui, Hawaii, devastated public and private land—destroying countless homes and businesses—the heat from the flames also damaged municipal water lines. Public health officials warned residents that filters were insufficient and that there was no “way to make [the water] safe.” The fire caused pressure loss in water lines, which let toxic chemicals, metals, and bacteria seep inside. Sometimes, simple breaches to the pipes can result in waste runoff mixing with public drinking water. Flames can also melt plastic liners inside pipes, resulting in toxic fumes flowing through water lines.
National Lead Crisis
According to a study from the National Library of Medicine, health officials recognized the link between lead pipes and lead poisoning as far back as the late 1800s. Cities and towns began restricting the use of lead pipes by the 1920s. However, the lead industry, championed by the Lead Industries Association (LIA), lobbied against this pushback of lead plumbing. The LIA sent representatives to “speak with plumbers’ associations, local water authorities, architects, and federal officials.”The National Library of Medicine charged the LIA with publishing articles and books that “extolled the advantages of lead over other materials and gave practical advice on the installation and repair of lead pipes. The LIA’s activities over several decades, therefore, contributed to the present-day public health and economic cost of lead water pipes,” according to the study.
“Lead affects the nervous system in adults and children. Long-term exposure may lead to muscle weakness, kidney damage, high blood pressure, reproductive problems in both men and women, and miscarriage,” according to a Florida Department of Health fact sheet.
One of the states most affected by lead pipe poisoning is Michigan. State officials tried to save money in 2013 by redirecting the city of Flint’s water from the Detroit River to the local Flint River for the city’s 100,000 residents.
Even though the move was intended to be temporary until officials could connect to Lake Huron, residents almost immediately started complaining about the city’s water’s taste, smell, and brown color. Some experienced rashes and hair loss before a group of doctors measured increased lead levels in children’s blood and urged the city to stop drawing water from the Flint River.
Decades of chemical runoff made the Flint River’s water highly corrosive, and the lack of proper treatment of that water before it was sent through aging lead water lines beneath Flint resulted in lead leaching into the city’s drinking water, according to the NRDC.
Michigan Gov. Rick Snyder announced in 2015 that the state would spend $1 million to buy water filters and test the water in Flint public schools. The ensuing years saw Mr. Snyder distribute bottled water and filters to Flint residents while asking the Obama administration for federal aid and a major disaster declaration. While investigators unraveled the threads of blame and eventually charged several state and local officials for the disaster—and then acquitted all but one official—Michigan ended bottled water distribution in 2018 after saying the city’s tap water had improved.
While Flint residents now have access to clean drinking water, those living in Benton Harbor, Michigan, faced a similar lead crisis in 2021. The city’s water tested positive for elevated lead levels three years in a row, prompting Gov. Gretchen Whitmer to allocate millions of dollars to replace the city’s lead water lines within 18 months. An investigation by the EPA found issues so dire with the city’s water treatment facility that the regulatory body recommended the city forfeit the plant’s ownership.
Lead Pipes in Florida?
In April, the EPA released a preliminary survey of lead pipes nationwide to determine how to allocate billions in money from the Bipartisan Infrastructure Law set aside for lead pipe replacements in each state. The full survey will base allocations on the number of lead pipes a state contains.Florida was at the top with an estimated 1.16 million lead pipes. States like Michigan, Ohio, and Pennsylvania are more often associated with extensive lead pipe use. Illinois was second on the list, followed by Ohio, Pennsylvania, Texas, and New York.
Some utilities said they were just beginning their inventories of lead water lines ahead of the EPA’s October 2024 deadline, while others do not remember being surveyed by the EPA in the first place, according to the EDF.
The environmental group gave Florida a new estimate of 100,000 lead water lines instead of the EPA’s 1.16 million. This estimate would reduce the Sunshine State’s lead line infrastructure allocation from $225 million to the $28 million baseline, the EDF said.
The Florida Department of Environment Protection (FDEP) did not respond to requests for comment.
Brian Miller, spokesperson for FDEP, shared similar concerns with the EPA’s findings in a statement to the Associated Press.
Highest Quality Water at the Lowest Affordable Cost
State officials found lead in several schools’ drinking water in 2019, prompting bipartisan action from the Florida legislature. It drafted a bill to put water filters in all schools built before 1986, when the state started using other metals in its water lines.Dr. Duranceau expressed a similar sentiment—unless there are other complex factors or contaminants in a public water source, “Granular activated carbon is the best available technology for those types of contaminants.”
GACs can be used in water treatment plants and bought for homes and businesses for added filtration to tap water.
The solution to water contamination is not always the most expensive and elaborate treatment setup. Sometimes, it is as simple as changing the source of a municipality’s drinking water, which is what Lake Mary did when it stopped drawing water from a well that tested positive for 1,4-dioxane at levels far higher than any other wells in the area, according to Ms. Koury. This move is also what Flint had to do after their initial change in water sourcing resulted in a national crisis.
According to Dr. Duranceau, every community and private water source—whether it is a well for a single home, school, or business—will require a water treatment plan that reflects the specific contaminants within its water. There is no single solution that works across the board in every location.
“People don’t realize what’s involved in getting water from a water plant to your tap safely so you don’t die,” Dr. Duranceau said. “You want to produce the highest quality water at the lowest affordable cost.”