This is a pretty comprehensive listing of old Pure Water Occasional issues.  Email issues going back to mid-2006 are listed in the table in reverse chronological order, beginning with the most recent. We haven’t counted them, but there are a bunch.  New issues are added periodically to the top of the list.

The Occasional is the offspring of the original Pure Water Gazette which began as a mail-out paper newsletter in 1986. The paper Gazette, discontinued in 1997, morphed into an online publication which started emailing some of its content as the Occasional sometime in the early 2000s.  The Gazette has existed since then as an online publication with “occasional” email issues.

Below the table, you will find duplicate listing of issues that are archived on the old Pure Water Occasional website.  This list, which mainly covers 2009 to 2013, contains broad subject headings.

You can sign up to receive new Pure Water Occasional issues by using the box on the right upper corner of this page or from the home page of the Pure Water Products website.

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Below is a list of partially indexed back Occasionals that may also be of interest.  These are archived on the Pure Water Occasional website:

Special Product-Specific Issues, 2010 to 2013

November 15, 2010. Undersink Water Filters.

December 15, 2010. Cartridge-Style Whole House Filters.

January 15, 2011. Multi-Pure Solid Carbon Block Filters.

February 15, 2011. Water Treatment with Aeration.

March 15, 2011. Pure Water Annie’s Concise Guide to Pumps.

April 15, 2011. Garden Hose Filters.

May 15, 2011. Water Filters for Emergencies.

June 15, 2011. Backwashing Water Filters.

July 15, 2011. Countertop Reverse Osmosis.

August 15, 2011. Whole House Reverse Osmosis.

September 15, 2011. Sediment Filters.

October 15, 2011. Tank-Style City Water Filters.

November 15, 2011. The Amazing Permeate Pump.

December 15, 2011. Template Assisted Crystallization (TAC).

January 15, 2012. Electro-Adhesion Filtration Technology: NanoCeram Filters.

February 15, 2012. Information About Information: How To Find Things on Our Websites.

March 15, 2012. Water Filter Cartridges. Featuring Our Recent Cartridge Page Revision.

April 15, 2012. Undersink Installation in Tight Places. Low Water Backwashing Filter.

May 15, 2012. Chloramines: Myth and Reality.

June 15, 2012. Whole House RO. San Angelo Water Treatment Dilemma.

July 15, 2012. Water Testing. Sand Trap.

August 15, 2012. Our New Water Test Page. Taking Care of A Water Well.

September 15, 2012. Ultrafiltration. Birthday of the EPA and Model 77.

October 15, 2012. Installing Undersink Filters and Reverse Osmosis Units.

November 15, 2012. Water Softeners and TAC units.

December 15, 2012. Twin Tank Water Softeners.

January 15, 2013. Standard-Sized Filter Cartridges.

February 15, 2013. Chemical Feed Pumps.

March 15, 2013. Countertop Reverse Osmosis.

General Issues, 2009 to 2013

September 2009. “Meshes and Microns: The Measurements of Water Treatment,” by Gene Franks. “Numerical water facts from B. Bee Sharper.”

October 2009. “Providing Water for Emergencies.” by Gene Franks. “Humming is Good for You,” by Hardly Waite.

November 2009. “How Much Water Should You Drink?” by Dr. Mauro Di Pascuale. “Numerical Facts about Animal Manure,” by B. Bee Sharper.

December 2009. “The New York Times Great Water Article,” by Hardly Waite. “Numerical Facts,” by B Bea Sharper.

January 2010. “What Carbon Does and What It Doesn’t,” by Gene Franks. “Numerical Facts,” by Bee B. Sharper. “Acidic Water.”

February 2010. “Fluoridation: The Good, the Bad, and the Ugly, Part I,” by C. F. “Chubb” Michaud.

March 2010. “Fluoridation: The Good, the Bad, and the Ugly, Part II,” by C. F. “Chubb” Michaud.

April 2010. NSF/ANSI. What Is It All About? by Gene Franks. Dr. Douglas on bath pharmaceuticals. B. B. Sharper. Radium.

May 2010. “The Ceiling is Up and the Floor is Down: The Alamo Engineering Handbook,” by Gene Franks. Steve Maxwell on “Why Water Should Cost More.” Iron.

June 2010. “All About Water Softeners,” Occasional Staff Article. “Gulf Oil Spill: A Hole in the World,” by Naomi Klein (Guardian). B. Bee Sharper, “On Prescription Drugs.” Hardness.

July 2010. “Raising the pH of Acidic Waters,” by Pure Water Annie. “Arsenic,” with a long cut from National Geographic News, New Products from Pure Water Products.

August 2010. “Winterize Your Lawn,” Model 77’s 21’s Birthday, Pure Water Annie on Servicing Model 77, MTBE.

September 2010. “Getting a Perspective on Water Use,” by Gene Franks. The Permeate Pump and How to Add a Permeate Pump to Your RO Unit. “Nickel.” B. B. Sharper on Groundwater Usage.

October 2010. “Air and Carbon,” by Gene Franks. Pure Water Annie on Airgap Faucet Installation. New EPA rule on dental mercury. “Chloride.” The Dead Sea. B. Bea Sharper on Billions.

November 2010. “How to Fix Leaks in Quick Connect Fittings,” by Pure Water Annie. “A Simmering Water War,” by Jim Hightower, “Is Your Faucet Making you Sick?” by Doug Linney, B. Bea Sharper on Water, “Radium and Uranium,” and Lead (contaminant of the month).

December 2010. “Probable carcinogen hexavalent chromium found in drinking water in 31 U. S. Cities,” by Lyndsey Layton. “Most of the time no one is watching most of the water for most of the contaminants, “by Hardly Waite. “How to remove Hexvalent Chromium,” and “How Static Mixers Work,” by Pure Water Annie.

January 2011. How Much Sodium Does a Softener Add to Water?, Water Treatment for Rainwater, Fluoride Allowable in City Water Lowered, UnTruth in Advertising, Pure Water Annie’s Whole House Filter Sizing Chart.

February 2011. More about Hexavalent Chromium, Ten Things You Should Know About Water, “What Carbon Does, What Carbon Doesn’t,” by Gene Franks, The Ups and Downs of Filter Cartridges (Which End Goes Up), by Pure Water Annie. B. Bea Sharper on Dams and other issues.

March 2011. Hardly Waite on National Water Security Rankings, Pure Water Annie on Finding Parts for Your Water Filter, and Introducing the Emily Reverse Osmosis Unit.

April 2011. Rain Barrels, Plastics, Introducing The Eliminator, A New Website Address. “In Praise of Tap Water.”

May 2011. UV 101 by Gene Franks, Rain Gardens, Water Content of Trees, Fiberglass Mineral Tanks.

June 2011. Sizing Water Softeners by Pure Water Annie, Meshes and Microns by Gene Franks, Swimming Pool Leaks, Saving A Cell Phone from Water.

July 2011. Sizing Water Softeners Part 2, by Pure Water Annie. Dr. Mercola on Nitrosamines, Choramine, and Shampoo Ingredients. B. B. Sharper.

August 2011. The Best Water for Coffee and Tea. Multiple Filter Designs. Tiger Tom Explains How UV Works.

September 2011. The Power and Water Nexus. Pure Water Annie explains “The Peroxide Number.”

October 2011, Pure Water Annie’s Glossary of Water Treatment Abbreviations, Chloramines and Fish, The EPA, Water and Coal.

November 2011. Pure Water Annie on Pipe Threads. Gene Franks and Hardly Waite on Christmas Gifts. The Origins of Fluoride.

December 2011. Pure Water Annie on Well Pumps. Top Water News Stories of the Year.

January 2012, Pure Water Annie on Chlorine. Arsenic. Texas Drought. Texas Water.

February 2012. Pure Water Annie on Benzene. Lake Vostok. Banning Bottled Water.

March 2012. Pure Water Annie on Copepods. B. Bea Sharper on plastic bags. Fluoride in Food.

April 2012. Pure Water Annie on Booster Pumps. B. Bea Sharper on dog manure. USA Today on Dog Excrement. New Easiest Ever Filter. Arsenic.

May 2012. Pure Water Annie on Treating Water with Sodis and Salt, Hardly Waite on “fracking” and water treatment profits, B. B. Sharper on Animal Manure.

June 2012. Pure Water Annie on In/Out Filters. New “Sand Trap.”

July 2012. Pure Water Annie Explains How Undersink Reverse Osmosis Works. The Economy RO Unit.

August 2012. Chlorine, Cholesterol, and Chickens.

September 2012. Reverse Osmosis and Refrigerators. The New Contaminant Index. Meat and Water Consumption. B. Bea Sharper.

October 2012. Bypass Valves, Watts UV, New Green Filters, Decaffeination.

November 2012. Septic Tanks, Whole House Filters, Calcium Scaling, How Softeners Work.

December 2012. Mercury in Tuna, Rainwater Runoff (Ocean Pollution), How To Sanitize An RO Tank, Winter Swimming, B. Sharper.

January 2013. Green Water Management. Pure Water Annie on Microbe Control. Camp Lejeune’s Shameful Water Scandal.

February 2013. Hardness, Pharmaceuticals and Fish, Pure Water Annie on “Pressure, Flow Rate, and Delta P.”

March 2013. Alum, Sinkholes, pH, Multi-Pure.

“Taking a sledgehammer to the Clean Water Act”

Cleveland’s Cuyahoga River before the Clean Water Act. The Cuyahoga was so chemical-laden that it caught on fire several times.

The Trump administration will formally start the process of lifting federal Clean Water Act protections for millions of acres of wetlands and thousands of miles of streams across the U.S., undoing decades of protections against pesticide runoff, industrial waste, and other pollutants. The proposed rules, to be unveiled by the Environmental Protection Agency in December, 2018, are a victory for agricultural and real estate interests but are likely to degrade the drinking water used by tens of millions of Americans and endanger fisheries and the habitats of migratory birds and other species.

President Trump promised during his campaign to roll back the Obama-era Waters of the United States rules, an expansion of federal protections under the the Clean Water Act of 1972, but the new Trump proposals target protections dating back to the George H.W. Bush administration or earlier. The Trump rules, which will be subject to 60 days of public comment, will keep protections for larger bodies of water but remove federal safeguards for wetlands not adjacent to navigable waterways plus most seasonal streams and ponds. The newly vulnerable streams provided drinking water for as many as 1 in 3 Americans, especially in the arid West, according to scientific studies used by the Obama-era EPA. And when small streams are polluted, they feed into larger streams and lakes, affecting the quality of drinking water for the entire nation.

The Trump EPA calls that data incomplete and will argue that it is tackling an Obama-era federal power grab against rural farmers. Trump’s promise to end the Waters of the United States policy was cheered by farmers, real estate developers, golf course owners, and mining and oil firm. Environmental groups call the new proposal a disaster. “It is hard to overstate the impact of this,” Blan Holman, managing attorney at the Southern Environmental Law Center, told the Los Angeles Times. “This would be taking a sledgehammer to the Clean Water Act and rolling things back to a place we haven’t been since it was passed. It is a huge threat to water quality across the country, and especially in the West.”

Adapted from: The Week.

Reference: Trump proposes to roll back decades of water protections” from Politico.

We call this picture “Cement River in Winter Viewed from the Bolivar Street Bridge”.  It features one of the “season streams” that are no longer protected by the Waters of the United States rules. All water is connected. When you pour motor oil into the Cement River, it eventually makes its way into somone’s drinking water reservoir.

The Fourth National Climate Assessment: What It Says About Water and Climate Change

The US Government’s Fourth National Climate Assessment, issued in the fall of 2018, devotes a long chapter to the effects of climate change on the nation’s water. Below are excerpts from the chapter which highlight its  important features.

National Climate Assessment: Highlights from the Water Chapter

by Emily McBroom

Rising air and water temperatures and changes in precipitation are intensifying droughts, increasing heavy downpours, reducing snowpack, and causing declines in surface water quality, with varying impacts across regions. Future warming will add to the stress on water supplies and adversely impact the availability of water in parts of the United States.

Changes in the relative amounts and timing of snow and rainfall are leading to mismatches between water availability and needs in some regions, posing threats to, for example, the future reliability of hydropower production in the Southwest and the Northwest. Most U.S. power plants rely on a steady supply of water for cooling, and operations are expected to be affected by changes in water availability and temperature increases.

Groundwater depletion is exacerbating drought risk in many parts of the United States, particularly in the Southwest and Southern Great Plains.

Dependable and safe water supplies for U.S. Caribbean, Hawaii, and U.S.-Affiliated Pacific Island communities are threatened by drought, flooding, and saltwater contamination due to sea level rise.

Aging and deteriorating water infrastructure, typically designed for past environmental conditions, compounds the climate risk faced by society. Water management strategies that account for changing climate conditions can help reduce present and future risks to water security, but implementation of such practices remains limited.

Changes in Water Quantity and Quality

Changes in climate and hydrology have direct and cascading effects on water quality. Anticipated effects include warming water temperatures in all U.S. regions, which affect ecosystem health, and locally variable changes in precipitation and runoff, which affect pollutant transport into and within water bodies.

These changes pose challenges related to the cost and implications of water treatment, and they present a risk to water supplies, public health, and aquatic ecosystems.

Increases in high flow events can increase the delivery of sediment, nutrients, and microbial pathogens to streams, lakes, and estuaries; decreases in low flow volume (such as in the summer) and during periods of drought can impact aquatic life through exposure to high water temperatures and reduced dissolved oxygen.

The risk of harmful algal blooms could increase due to an expanded seasonal window of warm water temperatures and the potential for episodic increases in nutrient loading.

In coastal areas, saltwater intrusion into coastal rivers and aquifers can be exacerbated by sea level rise (or relative sea level rise related to vertical land movement), storm surges, and altered freshwater runoff. Saltwater intrusion could threaten drinking water supplies, infrastructure, and coastal and estuarine ecosystems).

Indirect impacts on water quality are also possible in response to an increased frequency of forest pest/disease outbreaks, wildfire, and other terrestrial ecosystem changes; land-use changes (for example, agricultural and urban) and water management infrastructure also interact with climate change to impact water quality.

Deteriorating Water Infrastructure at Risk

Capital improvement needs for public water systems (which provide safe drinking water) have been estimated at $384 billion for projects necessary from 2011 through 2030. Similarly, capital investment needs for publicly owned wastewater conveyance and treatment facilities, combined sewer overflow correction, and storm water management to address water quality or water quality-related public health problems have been estimated at $271 billion over a 20-year period. To date, however, there is no comprehensive assessment of the climate-related vulnerability of U.S. water infrastructure, and climate risks to existing infrastructure systems remain unquantified.

Compound extremes, such as terrestrial flooding and ocean flooding occuring at the same time, can also increase the risk of cascading infrastructure failure since some infrastructure systems rely on others, and the failure of one system can lead to the failure of interconnected systems, such as water–energy infrastructure.

Water Management in a Changing Future

Paleoclimate analyses and climate projections suggest persistent droughts and wet periods over the continental United States that are longer, cover more area, and are more intense than what was experienced in the 20th century.

The challenge is both scientific, in terms of developing and evaluating these approaches, and institutional–political, in terms of updating the regulatory, legal and institutional structures that constrain innovation in water management, planning, and infrastructure design.

Source: The Fourth National Climate Assessment: Chapter Three.

What Carbon Treats and What It Doesn’t

Filter carbon is the most widely used treatment for water problems, the most commonly used filter medium.  It works for a broad range of applications, but as the chart below shows, it doesn’t do everything. The comments are generalizations. Some carbons work better for specific applications.

Filter carbon can be made from a variety of raw materials, processed in a variety of ways, and delivered in a variety of formats.

carbon pores illustration

How Caffeine Is Stripped from Coffee by Use of the Chemical-Free Water Method

Caffeine is in the coffee bean for a reason.  It’s a natural alkaloid that serves the coffee plant as a pesticide.  It paralyzes bugs that invade the plant and also gives off a bitter flavor as a warning of its toxic nature.

Caffeine is water soluble, as are most of the other ingredients of the bean that give coffee its flavor.

The art of decaffeination,  therefore, consists of stripping the caffeine from the coffee bean while leaving behind the desirable ingredients that provide the coffee taste and aroma.

Several methods are used to remove caffeine from coffee.  Many involve chemicals, but others rely almost entirely on water.  The water methods are definitely the more desirable.  The so-called Swiss Method is considered the standard of excellence.  Here’s how the process is described:

The green, or unroasted coffee is fully submerged in filtered water that has been heated, in order to extract all the soluble material from the beans. The water solution is then filtered through carbon to separate the caffeine compounds from any of the aromatics that also came out during the extraction, and the coffee beans are then placed in an immersion tank with the caffeine-free solution, allowing them to reabsorb everything but the jitters.

World standards differ on the definition of “decaffeinated coffee,”  some allowing 97% caffeine reduction, but the highest  standards require elimination of  as much as 99.9% of the alkaloid content of coffee in order to display the decaffeinated label.

Reference:

Serious Eats Website

Pure Water Gazette:  What Kind of Water Makes the Best-Tasting Coffee

America’s Dirty Little Secret

Water Online writer Sara Jerome, in her article “Small Town, Big Water Problems,” says that in the small Louisiana community of Enterprise, the tap water is so bad that “one woman drives 20 miles each way to do her laundry in another town.” The water situation in Enterprise illustrates a festering problem in the United States: Funding for infrastructure repairs and upgrades in small communities is hard to come by.

Jerome continues:

“Years of water system neglect means that the 250-or-so residents there are left with pipes that leak more than 70 percent of their water into the ground — all because they can’t afford to fix them,” CNN reported, citing John Tiser, resident and water board president.

But Enterprise is hardly alone.

“The EPA estimates $132.3B is needed to repair small water systems in America over the next 20 years. But, in 2017, only $805.7M was allocated to these systems — about 12 percent of the amount needed,” CNN reported.

Virginia Tech Engineering Professor and water expert Marc Edwards refers to it as America’s “dirty little secret.” He explains that oftentimes towns like Enterprise are stuck with aging infrastructure that they can’t fix, leaving few options for them to deal with complaints about dirty or contaminated water. Edwards received a nearly $2M grant to uncover water issues in towns like this.

When Edwards and a scientific team tested Enterprise’s water in 2017, they found bacteria, lead and other contaminants that exceeded EPA limits.

“The whole idea is, at the end of this, to come up with a model to predict which cities are likely to have problems,” Edwards said. “Which cities are most likely to have lead pipes, and not be following the rules, and then work with communities there to figure out if they do have a problem, then build algorithms for individual homeowners to protect themselves, from sampling to filters.”

It is important to point out that while “over 92 percent of U.S. residents who receive water from community water systems are supplied by water that meets health-based standards at all times,” the U.S. EPA estimates that over $743B is needed for water infrastructure improvements.

To illustrate the extent of the water problems that plague small U. S. systems, here are more Water Online articles:

Texas Town Confronts Brown Water Coming From Taps. Residents of River Oaks, TX, are tired of drinking brown tap water.

Study Finds That Millions Of Americans Get Water From PFAS-Laced Sources. The level of perfluoroalkyl substances (PFASs) in drinking water sources exceeds federal safety limits in supplies serving millions of U.S. residents.

Authorities Target Water Operator Over Lead Crisis In Ohio. Ohio authorities filed charges against a water operator last week, alleging that he failed to alert residents about lead levels in the village of Sebring, where tainted tap water has triggered elevated lead levels in children.

18 Million People Served By Systems With Lead Violations. Public officials have often failed to step in when water systems violate the federal Lead and Copper Rule, according to a report released this week by the advocacy group Natural Resources Defense Council (NRDC) on the “extraordinary geographic scope” of lead contamination.

Are The Dangers Of Iron In Water Being Ignored? Iron in drinking water may pose more health risks than federal water regulators currently acknowledge.

Reference Source: Water Online

Pure Water Gazette Fair Use Statement

Emerging Contaminants: The NSF List

The list of possible new water contaminants is endless, since new chemicals are issued much faster than regulators can test them.

Traditionally, ANSI/NSF certification has been divided into two categories: the contaminants with known adverse health effects, like arsenic, and items like the taste and color of water, which are aesthetic issues not known to affect health.

Emerging contaminants are a new category of water quality concerns for which evidence of health effects has not yet been established due in part to the trace levels at which these compounds are currently being detected.

The newer chemicals that are being listed by regulatory agencies are seen below in the Emerging Contaminants list being tested to a new NSF standard called American National Standard NSF/ANSI 401.  You’ll see some familiar names in the list. Yes, DEET is the stuff you spray on your body to discourage mosquitos,  Ibuprofen is what you take for a headache, and Bisphenol A (aka BPA) is the ingredient in plastic bottles you’ve been trying to avoid.

Note that the allowable amount for all of  these is expressed not in parts per million, or parts per billion, but in ng/L, nanograms per liter.  One nanogram per liter is one one-millionth of one milligram per liter. Expressed differently, one nanogram per liter is the equivalent of one part per million of one part per million of the whole. When you think of it as slicing a pie into a million pieces then one of the pieces into a million pieces, that isn’t much.

To understand how NSF testing is done, what the chart tells you is that if they take a solution containing more or less 200 ng/L of the angina and blood pressure medicine Atenolol and put it through a filtration device, the device must reduce the Atenolol content to 30 ng/L or less to receive NSF certification.

It is noteworthy that the fairly short list of devices that have attained NSF certification for removal of Emerging Contaminants includes only carbon filtration devices, and some of these are small devices like refrigerator filters or pitcher filters. The moral is that if you drink water from a good carbon-based drinking water filter, or a reverse osmosis unit, you can safely stop worrying about being overcome by the page-long list of health problems associated with the anti-seizure drug Carbamazepine.

Source of NSF Chart.

Q

EPA: GenX Nearly As Toxic As Notorious Non-Stick Chemicals It Replaced

Agency’s Review Comes 12 Years After Industry Began Phaseout of PFAS Compounds

GenX, introduced a decade ago as a “safer” alternative for the notorious non-stick chemicals PFOA and PFOS, is nearly as toxic to people as what it replaced, says an Environmental Protection Agency study released recently.

EPA published a draft toxicity review for GenX and a related compound called PFBS, both part of the PFAS family of chemicals. Environmental Working Group’s analysis of EPA’s assessment shows that very tiny doses of GenX and PFBS could present serious health risks, including harm to prenatal development, the immune system, liver, kidney or thyroid.

“It is alarming that, 12 years after DuPont, 3M and other companies, under pressure from EPA, began phasing out PFOA and PFOS, we find that replacements like GenX are nearly as hazardous to human health,” said David Andrews, Ph.D., senior scientist at Environmental Working Group.

“EPA scientists have given us valuable new information here, but the study’s real significance is to show that the entire chemical regulatory system is broken. EPA has allowed hundreds of similar chemicals on the market without safety testing, and it’s urgent that the agency evaluate the risk Americans face from all of these chemicals combined.”

GenX is a successor to PFOA, formerly used by DuPont to make Teflon. PFOA has been linked to cancer in people and to the reduced effectiveness of childhood vaccines and other serious health problems at even the smallest doses. GenX’s chemical structure is very similar to PFOA’s, but it was not adequately tested for safety before being put on the market, in 2009. DuPont has provided test results to the EPA showing that GenX caused cancer in lab animals.

GenX is used to produce non-stick coatings on food wrappers, outdoor clothing and many other consumer goods. A 2017 report by EWG and other groups found the GenX family of chemicals in food wrapping samples from 27 different fast food chains.

“The system has it backwards: Instead of putting the burden of proof on EPA to show that chemicals like GenX are safe, the chemical industry should be responsible for testing its products for safety before they’re put on the market,” said Andrews. “This broken system has enabled DuPont and other companies to contaminate nearly everyone on Earth, including babies in the womb, with these chemicals.”

DuPont’s Deception About Health Risks From Non-Stick Chemicals
In 2001, attorney Robert Bilott sued DuPont on behalf of 50,000 people whose drinking water had been contaminated by PFOA, the carcinogenic compound used to make Teflon at the chemical company’s plant in Parkersburg, W. Va. EWG published a series of investigative reports based on secret documents uncovered in the lawsuit, revealing that DuPont knew about PFOA’s dangers for decades but didn’t tell regulators or the public. EWG filed a complaint with the EPA, which led to a record fine against DuPont. Our research also found that the entire class of non-stick, waterproof chemicals had polluted people, animals and the environment in the most remote corners of the world.

Although PFOA and some related PFAS chemicals have been phased out, they still contaminate the drinking water of an estimated 15 million Americans. The saga of PFOA pollution in Parkersburg and beyond is told in “The Devil We Know,” a documentary available on streaming services.

Source: Environmental Working Group

50 years later, Sioux Falls manages contaminated water from toxic firefighting foam

Gazette Introductory Note: We’re reprinting this piece to illustrate the widespread problem with PFAS and to show how one water supplier has chosen to deal with it. Municipal treatment of this growing chemical threat to drinking water is difficult and expensive to say the least.

Sioux Falls SD officials are grappling with well shutdowns as the extent of the city’s water contamination from decades of firefighting foam use remains unclear.

Sioux Falls currently has 19 municipal wells sitting dormant in the aftermath of innumerable gallons of toxic firefighting foam that contaminated the grounds of the city airport nearly 50 years ago, the Rapid City Journal reported. Chemicals linked to cancer and other health issues were found to have contaminated 15 municipal wells, including 10 that have concentrations above what the Environmental Protection Agency deems safe.

About 28 percent of the city’s water production from the Big Sioux aquifer is shut down.

The South Dakota Air National Guard and the Sioux Falls Fire Department both used the toxic firefighting foam for many years near the airport, which led to the contamination of the city’s drinking water. But the scope of the issue is still unknown.

“We really haven’t determined the extent of release yet,” said Capt. Jessica Bak, a public affairs officer with the Air Guard at the Sioux Falls Regional Airport.

In 2013, the city’s water purification plant found chemicals from firefighting foam, known as per and polyfluoroalkyl substances (PFAS), at levels below the EPA’s health advisory level. The level of exposure beneath the EPA’s threshold means there aren’t expected adverse health risks.

The city responded to the findings by testing all municipal wells to identify the source and shutting down every well where the chemicals were found.

City engineer Tim Stefanich, who oversees the water system, acknowledged that “there was a little bit of time between” finding the contamination, determining its source and deciding to shut off wells. But he said that there was minimal fear of an immediate health risk with the low levels of exposure.

WQRF issues RFP for study on contaminants between MCL and MCLG

by Gene Franks

When I saw the headline above I knew I was going to have to learn some new acronyms. Just last week we put up an article about the difficulty writers and readers and researchers are having with the many new abbreviated forms used for “emerging contaminants” that start with “P.”  The world is being overrun by acronyms, and the water treatment industry creates way more than its share.

WQRF, I learned, stands for the Water Quality Research Foundation, which was formerly called the Water Quality Research Council (WQRC), which was formed in 1949 to serve on behalf of the Water Quality Association (WQA) as a universally recognized, independent research organization.

Then, I learned from the Wikipedia that RFP stands for “request for proposal.”   The RFP  is a “document that solicits proposal, often made through a bidding process, by an agency or company interested in procurement of a commodity, service, or valuable asset, to potential suppliers to submit business proposals.”

I already knew what MCL and MCLG mean, but to be sure I understood them in the context of the WQRF’s RFP,  I looked them up:

MCL stands for Maximum Contaminant Level: the highest level of a contaminant that is allowed in drinking water. MCLs are set as close to the maximum contaminant level goals (MCLG) as feasible using the best available TT (Treatment Technology).

MCLG stands for  Maximum Contaminant Level Goal: the level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety.

Here’s how the project goal itself is stated in the article:

This study is the first attempt at collecting and analyzing national occurrence data between the MCL and MCLG, utilizing data that is available from state and federal databases including, but not limited to: EPA, CDC, USGS, FRDS, NCOD, and SDWIS. Of the contaminants governed by the National Primary Drinking Water Regulations, only those that have a MCLG value lower than its MCL value (including MCLG values of “zero”) will be included in this research. 

FRDS, NCOD, and SDWIS, which I didn’t understand, I decided to leave it alone. You don’t have to know everything.

In regard to the “P” word contaminants that we went to so much trouble trying to classify, this very week, the Agency for Toxic Substances and Disease Registry (ATSDR), apparently a division of the CDC (Centers for Disease Control), seeing the urgent need to get everyone on the same page so these chemicals can be talked about, issued a very helpful document called The Family Tree of Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS) for Environmental Health Professionals.  I hope you’ll read it. It keeps things simple by showing only the main PFAS family and leaving off the subfamilies. It also drops one confusing acronym, PFC, from the tree, pointing out that PFC stood for perfluorinated chemicals and also for perfluorocarbons. They do not mention that it also stands for Private First Class, which probably confused lots of people. PFC shows on the picture above as a fallen apple.

One very edifying part of the Family Tree, though, is the clarification of the singular/plural issue. I learned I’ve been making some pretty dumb statements (as have most of the people who write about PFAS).  According to the ATSDR, PFAS is plural, so you shouldn’t add an “s” to it and write PFASs, as many, including me, have done. Putting an “s” on PFAS is like saying, “My uncle has three childrens and they all wear red hatss.”

We live and learn.

The Family Tree of PFAS.

See also, Pure Water Annie’s Glossary of Common Water Treatment Abbreviations  Pure Water Annie always crosses the t’s and dots the i’s and never puts s’s on plurals.