Water Quality InformationWritten By Actual Experts

Eric Roy, Ph.D.  |  Scientific Founder 

Today the City of Corpus Christi, TX alerted residents not to drink or bathe using tap water because a "backflow incident" had potentially contaminated the city's drinking water with Indulin AA-86, an emulsifier commonly used in the asphalt industry. As a result, we are getting a lot of questions about back-flow and Indulin AA-86 contamination from people in Corpus Christi, as well as the rest of the US.

What Is Backflow?

Backflow is a pretty simple concept. It simply means that the liquid in a plumbing line went in the opposite direction that it supposed to. In a residential setting, this happens if the pressure within the residential plumbing goes higher than the city's water pressure. This can happen if a water pump malfunctions, or if the city's water pressure unexpectedly drops (for example when a water main breaks). In an industrial setting, this typically happens as a result of operator error or when backflow devices are not installed properly.

When Is Backflow A Problem For Drinking Water?

Backflow becomes a problem when pipes used to transport drinkable water are connected to pipes that are carrying a solid, liquid, or gas that is not drinkable (also called a "cross-connection"). When backflow occurs, the non-drinkable substance flows into backwards into the potable water pipe, where it mixes with and contaminates the drinking water.

Difference between normal flow and backflow over a cross connection

What Is Indulin AA-86?

Indulin AA-86 is a trade name for an emulsifier commonly used in the asphalt industry. Because Indulin AA-86 is proprietary, the Material Safety Data Sheet (MSDS) is not required to disclose the chemical composition, so we can only look at clues. The MSDS does categorize the formulation as having fatty amine derivatives, and another MSDS for Indulin AA-86 discloses that several state regulatory agencies (including California Prop. 65) list ethyl acrylate as an ingredient. From this information, and other parts of the MSDS, we can assume that the substance as a whole is relatively insoluble in water, but because the specific formulation is disclosed, we do not know how soluble (if at all) the different components of Indulin AA-86 are.

How Did Indulin AA-86 Contamination Get Into Corpus Christi's Water?

At the time that this article was published, the details are pretty scarce. Corpus Christi estimates that between 3 and 24 gallons of Indulin AA-86 were flowed into the drinking water system, and that's about it. We'll keep you posted as more is learned.

***Update On 12/16: The disclosure that hydrochloric acid was backflowed gives us a huge clue into what happened. The presence of hydrochloric acid strongly suggests that already mixed emulsion solution, not the pure Indulin AA-86 chemical was backflowed. Indulin AA-86 is prepared in a 0.3% solution to form an emulsion. Therefore, for 24 gallons of Indulin AA-86 would be diluted with water into to 8,000 gallons, a volume that is a standard storage/mixing tank size in the industry. If I had to speculate, someone backflowed a full 8,000 gallon tank of prepared emulsion into the freshwater line that is used to fill the tank.

If this is what happened, it's a bad thing, because prepared emulsion will more readily mix with drinking water than the relatively insoluble Indulin AA-86 pure product.

What Now For Corpus Christi Residents?

As of the time of the publication, Corpus Christi is urging residents to drink, cook, and bathe with bottled water, while they learn more about the extent that the water supply has been contaminated.

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Emma Schultz, M.S.  |  Scientific Contributor

There has recently been a spate of schools testing positive for lead contamination in drinking water across the country, at dangerously high levels. Since the Flint, Michigan water crisis brought lead contamination and lead poisoning into the spotlight in 2015, there has been a push to increase water testing in schools - and rightly so. It’s not likely that high test results are new; it is unfortunately instead likely that this has been an ongoing undetected problem. EPA estimates that 90,000 public schools, as well as half a million child care facilities, are not regulated under the Safe Drinking Water Act due to utilizing a municipal water utility. While these statistics are dated (2002), they are still referenced by EPA. Since the utility is the responsible party for testing water, the school itself is not required to test, unless there are more stringent local laws or they voluntarily choose to do so. Most do not, or if they do, their results may not be reflective of normal lead levels. Water frequently stagnates in school pipes, due to nights, weekends, and summers where water usage is drastically diminished. That stagnation leads to leaching of lead in the school's water, and therefore lead accumulation, when there are lead pipes or lead-containing valves and fittings.

It is important to note that there is no such thing as a safe level of lead in drinking water. It bears repeating: no level of lead is safe, especially when it comes to children, who are most sensitive to lead poisoning. The EPA limit of 15 parts per billion, set in 1991, is much higher than EPA and CDC have admitted is safe (they agree, there is no safe level of lead). In addition, 10% of samples are legally allowed to exceed the 15 ppb threshold without resulting in any utility violations. In contrast, The American Academy of Pediatrics proposes that lead in school drinking water should not exceed 1 ppb.

Lead Contamination In Nashville, Tennessee Schools

One city that recently made headlines for lead contamination in public schools is Nashville, Tennessee. Schools were tested for lead during the summer of 2017. Examples of frighteningly high lead levels are as follows (note, these are individual tap results):

• Park Avenue Elementary: 170 ppb
• Spectrum Academy: 349 ppb
• Chadwell Elementary: 272 ppb
• Cole Elementary: 106 ppb
• Neelys Bend Elementary: 115 ppb

In addition, 11 fountains exceeded 5 ppb of lead at McMurray Middle’s annex, and 13 fountains at Hattie Cotton Elementary had greater than 5 ppb. Haywood Elementary had very high lead averages, with 26 drinking fountains testing greater than 5 ppb of lead, 9 of which were over 15 ppb.

Metro Nashville Public Schools (MNPS) reported that any tap showing lead levels above 15 ppb was subsequently disconnected, but shutting off one tap does not solve the problem. Public schools are often old, and old schools tend to have an old infrastructure, which includes lead-based plumbing. While MNPS does not state the age of their school buildings, several of the schools also made headlines this winter for being unable to heat their classrooms during a prolonged cold spell, with classroom temperatures dipping down to a frigid 46°. This aging infrastructure is putting students at risk in multiple way. Regarding lead in drinking water, MNPS has remained in the news because of a leaked recording where Executive Director of Facilities Dennis Neal plotted with staff to bypass the filtration systems on several dozen lead-filtering “filtration stations” that were installed in some of the more affluent schools (courtesy of parent donations) following the lead scare. Neal was concerned about the high cost of continuously filtering water across schools with high lead levels, and stated “People keep wanting these bottle fillers, but they are adamant about them being filtered. I’m saying we cannot support it.”

After the recording was leaked, Neal was put on administrative leave while MNPS investigated; he has since resigned. Issues remain with lead levels in schools though, and parents have every right to be concerned. MNPS District Spokesperson Michelle Michaud, in an interview with CBS This Morning, stated that filters aren’t actually needed, because the school district has reduced lead levels to under 15 ppb, and then claimed that filters can reduce the amount of lead in water no further than that. "Those filters are doing a good thing," Michaud said. "They are making the water taste better, but they are not filtering out more lead." This is in contrast to the fact sheet from one of their filtration providers, which states that lead levels will be reduced to 10 ppb or less. Hydroviv filters, in comparison, have treated water with 200 ppb of lead, reducing the lead in water to an output of 0 ppb.

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Analies Dyjak  |  Hydroviv Policy Analyst

While there’s a lot of debate on what should and shouldn’t be regulated in terms of chemical discharge by companies, we thought that it would be interesting to show how regulations are used in the real-world.  In this article, we talk about the permits that allow entities to discharge chemicals into sewers and waterways.

What Is An NPDES Permit?

The National Pollutant Discharge Elimination System (NPDES)
Permits disclose which chemicals companies are allowed to discharge into waterways, and at what concentrations. The overall goal of a NPDES permit is to provide transparency between the polluter, the federal government and the public.

Who Needs To Get An NPDES Permit?

Any company, organization of private entity that has plans to discharge pollution from a point source into a United States waterway.

How Are NPDES Permits Granted & Distributed?

Technology-based and water quality based limitations are two criteria that are considered when issuing a permit. Technology-based limitations take into consideration the technology and economic ability of the polluters to control the discharge of pollutants from their facilities. Water quality-based limitations are meant to protect the body of water that the effluent is being discharged into.
Once a permitting authority or company completes a Notice of Intent (NOI) for a NPDES permit, it becomes available to the public via the Federal Register. Often local newspapers will publish a notice of the application and provide information regarding public comments.

Where Can I Find an Existing NPDES Permit?

Existing NPDES permits can be found in the General Permit Web Inventory section of the EPA’s website. Required information to search for a NPDES permit includes either the name of a state, permit number, or permitting authority.

What Should A NPDES Permit Include?

• Information on each known contaminant must be included in a NPDES permit, whether it is regulated by the EPA or not.

• Clear, concise, and consistent units. When a regulatory agency signs off on a NPDES permit without units, they’re essentially allowing a company to discharge a contaminant at any concentration.

• Pertinent information that might affect concentration levels.

• For example seasonal variance or increased turbidity.

• A NPDES permit should also have information on monitoring such as location and frequency of sampling.

Why You Should Care About NPDES Permitting

Public participation has the ability to prolong the issuing process and can cause a company to alter their plans for dealing with chemical discharge. If you have questions regarding a NPDES permit in your area, don’t hesitate to address your concerns during the required public comment period. Be vigilant in assessing every component of the water discharge permit!

Want To Learn More About NPDES Permits And Water Policy?

Feel free to reach out to our Water Nerds through live chat or email (hello@hydroviv.com).  We're happy to help you out!

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Analies Dyjak  |  Policy Nerd

This week, Hydroviv is highlighting the six new National Priorities List (NPL) sites under the EPA Superfund program. Superfund sites are home to high levels of hazardous soil and groundwater contamination from years of improper disposal techniques. If you’d like to learn more about the ins and out of Superfund, check out our recap HERE. The next Superfund site that we’ll be discussing is located in Spring Park, Minnesota. 

Spring Park, Minnesota is home to one of the six newly designated Superfund sites. The town’s municipal well field is contaminated with several industrial solvents such as trichloroethylene (TCE), 1,2-dichloroethylene (DCE) and vinyl chloride. There are 1,673 residents in Spring Park, all of which are serviced by the same municipal well field. Two of the three municipal wells currently exceed Maximum Contaminant Levels for TCE. EPA has stated that the source of the contamination is unknown, but all contaminants are frequently used as industrial solvents.

If you live near a Superfund site and are concerned about your water, drop us an email at hello@hydroviv.com or visit hydroviv.com and use our live chat feature. Hydroviv is staffed with scientists and policy experts that can help you make sense of your water and find an effective filter, even if it isn’t one we sell.

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Updated 6/5/20 to include new information

Ernesto Esquivel-Amores and Analies Dyjak  |  Water Nerds   

On June 14th, 2017 the North Carolina Department of Environmental Quality began its investigation into a chemical called GenX. Despite just recently gaining major media attention, Per and Polyfluoroalkyl Substances (PFAS) have been a threat to public health for decades. PFAS are associated with the production of Teflon, Scotchgaurd, and other non-stick/stain resistent household products. The timeline below specifically highlights one type of PFAS called GenX, but it's important to keep in mind that there are hundreds of thousands of PFAS chemicals present in the environment. This article discusses the past, present, and future of GenX, and progress being made reduce the threat to human health and the environment.

1980

Dupont, the chemical manufacturing company began discharging Perfluorooctanoic acid (PFOA), also known as C8, into the Cape Fear River in Fayetteville, North Carolina. Dupont purchased PFOA from 3M, which is another chemical manufacturing company out of Minnesota. PFOA is an ingredient that’s used during the manufacturing of heat and water resistant products. The Fayetteville plant was and is still located on the Cape Fear River, which is the primary drinking source for Brunswick, Bladen, New Hanover, and Pender counties.

March 2002

DuPont and EPA established a temporary threshold level of 14,000 parts per trillion for PFOA. This agreement, made under the Safe Drinking Water Act, had a condition that required DuPont to pay for alternative sources of drinking water for affected users if water samples tested higher than the agreed upon threshold.

October 2002

3M stopped manufacturing PFOA because the company recognized its harmful effects to human health and the environment. Later in 2002, DuPont began making the same chemical at its Fayetteville plant in North Carolina.

2005

EPA penalizes DuPont with a $10.25 million lawsuit for failing to report information about “substantial risk of injury to human health and the environment.” EPA also required DuPont to give $6.25 million to fund various environmental programs. At the same time DuPont and other PFOA manufacturers came to an agreement to “voluntarily” phase out production by 2015. 

2009

DuPont began to voluntary use GenX as a substitute for PFOA at the Fayetteville plant. DuPont claimed this substitute was a safer alternative to PFOA.

January 2009

DuPont informed EPA that they would begin manufacturing GenX at the Fayetteville plant. A few weeks later, EPA entered a separate consent order with DuPont to address dealing with the GenX chemical discharge into the water and air. DuPont was able to find a loophole in the consent order that does not apply to substances produced as the byproducts of other processes. This means that GenX could be discharged without needing to follow the terms of the consent order.

March 2009

A new consent order between EPA and DuPont under the Safe Drinking Water Act required that the threshold of PFOA levels need to be reduced from the previous threshold of 14,000 to 400 parts per trillion. This new order also stated that the company must provide alternative water sources to areas with PFOA levels exceeding the new threshold.

2012

The North Carolina DEQ approved DuPont’s wastewater discharge permit. Additionally, the North Carolina Science Advisory Board recommended setting at max limit of 1000 parts per trillion for PFOA in groundwater. Later that year, North Carolina State University scientists find GenX in the Cape Fear River for this first time.

2015

DuPont created spin off company from their division of “Performance Chemicals” called Chemours. Chemours is now in charge of manufacturing and discharging fluorinated contaminants.

2016

The team at NC State released a report detecting GenX chemical in Cape Fear water. Contamination was associated with discharge from the Chemours plant upstream of the drinking water source.The researchers found that on average there was a GenX concentration of 631 parts per trillion per liter. NC State researchers tested various filtering methods to remove GenX from the drinking water. As it turns out, GenX is a harder chemical to filter out from water then the previous chemical PFOA.

2017

North Carolina DEQ began investigating Chemours for their discharge of waste water into the Cape Fear River. Chemours then revealed that their predecessor company has been discharging various fluorinated compounds since the 1980’s and announced that it will capture, remove, and safely dispose of them rather than discharge contaminants into the river.

June 14, 2018

Today, the GenX dilemma in North Carolina remains unsolved. Community members have rallied to make the nation aware of this public health debacle. Additionally, the North Carolina house and senate are trying to pass a wonky bill that only addresses one of the several dangerous chemicals in the Cape Fear watershed. Sponsors of the North Carolina Water Safety Act have essentially created a bill that caters to polluters. While the bill aims to regulate GenX chemical contamination in water, it fails to mention all of the other fluorinated compounds. This means that Chemours will only be held accountable to address GenX contamination, while continuing to produce and allow other fluorinated chemicals to run rampant in the Cape Fear River. Our Water Nerds believe that GenX should not necessarily be the star of the show. The entire class of fluorinated compounds need to be addressed when discussing North Carolina’s water quality and the absence of a comprehensive regulation. There's a laundry list of fluorinated compounds that the NC state laboratory detected in their initial water testing. Perfluorobutanoic acid (C4), Perfluoropentanoic acid (C5), Perfluorbutane sulfonic acid (PFBS), and Perfluoro-3-methoxypropanoic acid (PFMOPrA) are just some of the fluorinated compounds that NC State detected in Cape Fear's water. GenX is easy to say and sounds intimidating, but that doesn’t necessarily make it the most dangerous fluorinated compound in Cape Fear’s water.

April 10, 2024

The US EPA has just announced drinking water standards to limit exposure to 6 types of PFAS chemicals, including an enforceable level of 10 ppt for GenX (also known as HFPO-DA).