Study: 270,000 tons of plastic floating in oceans

by Audrey McAvoy

A new study estimates nearly 270,000 tons of plastic is floating in the world’s oceans. That’s enough to fill more than 38,500 garbage trucks.

The plastic is broken up into more than 5 trillion pieces, said the study published Wednesday in the scientific journal PLOS ONE.

The paper is the latest in a nascent field where scientists are trying to better understand how much of the synthetic material is entering the oceans and how it’s affecting fish, seabirds and the larger marine ecosystem.

The study’s lead author is Markus Eriksen of the 5 Gyres Institute, an organization that aims to reduce plastic in the oceans.

To gather data, researchers dragged a fine mesh net at the sea surface to gather small pieces. Observers on boats counted larger items. They used computer models to calculate estimates for tracts of ocean not surveyed.

The study only measured plastic floating at the surface. Plastic on the ocean floor wasn’t included.

Bits greater than about 8 inches accounted for three-quarters of the plastic that the research estimated is in the ocean.

Kara Lavender Law of the Sea Education Association in Woods Hole, Massachusetts, who wasn’t involved in the study, said the researchers gathered data in areas where scientists currently don’t have measurements for floating plastic debris, including the Indian Ocean, the Southern Ocean near Antarctica and the South Atlantic.

In addition, the study’s estimate for tiny plastic bits less than one-fifth of an inch — about 35,540 tons — is comparable to an earlier study by researchers in Spain who used different methodology, Law said. That study estimated there was 7,000 to 35,000 tons of plastics this size floating in the ocean.

It’s encouraging that two different approaches came up with such similar answers, given how difficult it is to measure plastic in the ocean, she said.

Studying the amount of plastic in the ocean will help scientists understand how the material will affect the environment and potentially the food chain.

For example, Law said, we might eat tuna that has ingested another fish that has eaten plastic that has in turn eaten another fish with plastic. These plastics could potentially have toxic chemicals.

“Am I being poisoned by eating the fish on my plate?” she asked. “We have very little knowledge of the chain of events that could lead to that. But it’s a plausible scenario that plastic ingested at lower levels of the food web could have consequences at higher levels of the food chain.”

Source: Poughkeepsie Journal.

Pure Water Gazette Fair Use Statement

What Happens to All the Salt We Dump On the Roads?

In the U.S., road crews scatter about 137 pounds of salt per person annually to melt ice. Where does it go after that?

by Joseph Stromberg

As much of the country endures from the heavy snowfall and bitter cold that has marked the start of 2014, municipalities in 26 states will rely on a crucial tool in clearing their roads: salt.

Because the freezing point of salty water is a lower temperature than pure water, scattering some salt atop ice or snow can help accelerate the melting process, opening up the roads to traffic that much sooner. It’s estimated that more than 22 million tons of salt are scattered on the roads of the U.S. annually—about 137 pounds of salt for every American.

But all that salt has to go somewhere. After it dissolves—and is split into sodium and chloride ions—it gets carried away via runoff and deposited into both surface water (streams, lakes and rivers) and the groundwater under our feet.

Consider how easily salt can corrode your car. Unsurprisingly, it’s also a problem for the surrounding environment—so much that in 2004, Canada categorized road salt as a toxin and placed new guidelines on its use. And as more and more of the U.S. becomes urbanized and suburbanized, and as a greater number of roads criss-cross the landscape, the mounting piles of salt we dump on them may be getting to be a bigger problem than ever.

Data from long-term studies of watersheds bear this out. A group of scientists that tracked salt levels from 1952 to 1998 in the Mohawk River in Upstate New York, for instance, found that concentrations of sodium and chloride increased by 130 and 243 percent, respectively, with road salting the primary reason as the surround area became more developed. More recently, a study of a stream in southeastern New York State that was monitored from 1986 to 2005 found a similar pattern, with significant annual increases and road salting to blame for an estimated 91 percent of sodium chloride in the watershed.

Because it’s transported more easily than sodium, chloride is the greater concern, and in total, an estimated 40 percent of the country’s urban streams have chloride levels that exceed safe guidelines for aquatic life, largely because of road salt. 

This chloride can occasionally impact human water use, mostly because some penetrates into the groundwater we tap for drinking purposes. Water utilities most frequently report complaints of salty drinking water during the winter, when chloride concentrations are likely to exceed 250 parts per million (ppm), our tastebuds’ threshold for detecting it. This is an especially big issue for people on salt restrictive diets. Overall, though, road salt-laced drinking water isn’t a widespread problem: A 2009 USGS study found that fewer than 2 percent of the drinking wells sampled had chloride levels that surpassed federal standards.

Road salt pollution is generally a bigger issue for the surrounding environment and the organisms that live in it. It’s estimated that chloride concentrations above 800 ppm are harmful to most freshwater aquatic organisms—because these high levels interfere with how animals regulate the uptake of salt into their bodies—and for short periods after a snow melt, wetlands nearby highways can surpass these levels. A range of studies has found that chloride from road salt can negatively impact the survival rates of crustaceans, amphibians such as salamanders and frogs, fish, plants and other organisms. There’s even some evidence that it could hasten invasions of non-native plant species—in one marsh by the Massachusetts Turnpike, a study found that it aided the spread of salt-tolerant invasives.

On a broader scale, elevated salt concentrations can reduce water circulation in lakes and ponds (because salt affects water’s density), preventing oxygen from reaching bottom layers of water. It can also interfere with a body of water’s natural chemistry, reducing the overall nutrient load. On a smaller scale, highly concentrated road salt can dehydrate and kill trees and plants growing next to roadways, creating desert conditions because the plants have so much more difficulty absorbing water. In some cases, dried salt crystals can attract deer and moose to busy roads, increasing their chance of becoming roadkill.

How can we avoid killing trees and making roadkill of deer while de-icing the roads? Recently, in some areas, transportation departments have begun pursuing strategies to reduce salt use. Salting before a storm, instead of after, can prevent snow and ice from binding to the asphalt, making the post-storm cleanup a little bit easier and allowing road crews to use less salt overall. Mixing the salt with slight amounts of water allows it to spread more, and blending in sand or gravel lets it to stick more easily and improve traction for cars.

Elsewhere, municipalities are trying out alternate de-icing compounds. Over the past few years, beet juice, sugarcane molasses and cheese brine, among other substances, have been mixed in with salt to reduce the overall chloride load on the environment. These don’t eliminate the need for conventional salt, but they could play a role in cutting down just how much we dump on the roads.

Source: Smithsonian.com

Whole House Reverse Osmosis

by Gene Franks

A residential whole house reverse osmosis unit consists of more than just the reverse osmosis unit itself.  Usually, some pretreatment will be needed, a  storage tank is required, and the water will then have to be post-treated and pumped into the home.

The Reverse Osmosis Unit

There are many excellent residential whole house reverse osmosis units on the market. They are usually classified according to the number of gallons per day of “permeate” (finished water)  they are rated to produce.  GPD ratings are purely theoretical: the actual production depends on the nature and conditions of the treated water. TDS (total dissolved solids), for example, affects production rates considerably, as does water temperature.  When furnished a detailed water analysis for the water to be processed,  RO manufacturers will usually perform an analysis called a ROSA test that gives a fairly accurate prediction of the actual production and the quality of the finished product.

Axeon AT Series RO Unit.  Units in this series produce in the 500 to 1000 gallon-per-day range. When you get the unit, it has been run and tested–it’s ready to install and use.

Typical GPD sizes for residential RO units are 500, 1000, 1500, and even more.  Sizing adequately is important, and over-sizing a little doesn’t hurt.  A lot more capacity than you need, however, is not good for the equipment.  RO thrives on work and it’s better for the equipment to run several hours per day than to make an occasional short run and shut off.  Consider your household needs.  Unless you have special uses like extensive irrigation, about 75 gallons per day per person is usually enough. Keep in mind, however, that you might get only 200 gallons of actual output from a 500 gallon unit and the unit might have to run virtually continuously to keep up with the demand,  so a 1000 GPD unit might be a better choice for a two-person home than a 500.  In most cases, too,  1000 costs only a bit more than 500,  and larger units are usually more efficient than small ones.

Pretreatment

Reverse osmosis can tame some very challenging water by reducing dissolved solids levels by almost 100% and removing arsenic, nitrates, and lead, and other problem contaminants, but the RO membranes themselves must be protected from contaminants like iron, hardness, manganese, turbidity, silica, and chlorine.  Pretreatment can require an iron filter, a water softener, sediment filtration and/or chemical scale inhibitors. Pretreatment is not optional.  Although the RO unit can itself remove the calcium that causes hardness scaling, untreated hardness will eventually scale the membrane, and membrane replacement is costly. Keep that in mind when considering a whole house RO installation.  Consider, too, that iron filters and softeners have to be allowed some time to regenerate themselves when the RO unit is not running.  This can affect sizing.

Filters and/or softeners may be needed to pre-treat water for iron, hardness, sediment–anything that can damage the reverse osmosis membrane.

Post Treatment

RO water is naturally low in pH, so it often a good idea to send it through a small neutralizing filter (usually calcite) to bump the pH back into the 7 range. This protects plumbing fixtures and can make the water more aesthetically pleasing.  Also, after the water has been stored in a tank,  a small carbon postfilter will improve the taste.  Finally, an ultraviolet lamp can assure safe, bacteria-free water.  Calcite, carbon filters, and UV are all optional, but you should consider them seriously.

Delivery System

Reverse osmosis units make water slowly, so storage is necessary to assure that enough water will be on hand for domestic needs.  The standard whole house RO storage vessel is a plastic, un-pressurized (atmospheric) tank.  The RO unit produces water into the tank; when the tank is full, a float valve turns off the RO unit.  When the water level drops, the float valve restarts the RO unit to refill the tank. To send water to the home, a delivery pump is used.  Some modern pumps (Grundfos is the leading brand) require no pump tank and send a smooth surge of water to the home when a faucet is opened or an appliance asks for water.

Common tank sizes are 165, 300, 500, and 1000 gallons.  A 300 gallon tank is plenty big for most domestic RO installations.  Keep in mind that if your RO unit is a high producer, you can get by with a smaller storage tank.  Typically, RO tanks need 4 holes.  One on the side near the bottom from which water is sent to the home, one for the float valve, one for RO water to enter the tank,  and one to serve as an overflow safety device in case the float valve fails to turn off the RO unit. The last three holes are near the top of the tank.

One More Thing

Something people often fail to think about when they consider installing whole house reverse osmosis is the brine, or “waste water.”  There will normally be a lot of it. You’re almost certain to have at least as much brine to get rid of as good water to use. You probably won’t want to put it into a septic tank.  What you’re going to do with the brine is something you should work out before you purchase a whole house RO unit.

Let’s Bring Back Bottle Messaging

by Tiger Tom

Gazette Social Critic Tiger Tom Speaks Out on the Lost Art of Message-in-a-Bottle Communication

One of the great forms of human communication, putting a written message into a bottle and tossing it into a body of water,  has been on the decline in recent years and I, for one, would like to see it come back.  That message-in-a-bottle communication has been eclipsed by smoke signals, pony express, telephones, email, text-messaging and other such fads is understandable to a degree, since these methods have a few advantages.  But I feel bottle tossing has redeeming qualities that we should reconsider.

The origins of bottle messaging are obscure, the only thing certain being that the practice did not develop before the invention of bottles that were light enough to float.  Messaging with stone bottles never got popular.  The first glass bottles were produced around 1500 B.C., and it’s hard to understand how someone didn’t immediately launch a bottle message;  but it is generally believed that the first known messages in bottles were released around 310 BC by the Ancient Greek philosopher Theophrastus as part of an experiment to show that the Mediterranean Sea was formed by the inflowing  Atlantic Ocean.

Bottle messaging was widely used by the time of Columbus,  who tossed a bottled message addressed to Queen Isabel into the ocean when he feared his ship might not make it through a storm.  The message has not surfaced to this day.  Finding it would be a big event and the message would certainly fetch big bucks on Ebay.

In the 16th century, bottle messages were used by the English navy and others to send strategic information to government officials; these were viewed as so important that Queen Elizabeth decreed the death penalty for unauthorized un-corking of bottled messages.  Hacking of personal messages was taken seriously then as now.

One thing that held bottle messaging back in earlier times was the high cost of bottles. It wasn’t until 1903 that the first automatic glass blowing machine was invented and glass bottles became ubiquitous and cheap. Before that, bottles were expensive and only the well-off could afford bottle messaging, even when shipwrecked or otherwise in dire straits.

Who, I’m sure you’re asking, holds the record for the oldest tossed-bottle message in existence? Since Theophrastus’ and Columbus’ offerings are still out there, the record goes to Richard Platz, who on a nature trail along the German Baltic Coast wrote a message on a postcard, put it in a beer bottle, corked it, and pitched it into the Baltic. That was in 1913.  The message was found by fishermen 97 years later.   The message, which wasn’t profound or in any way important in itself, leading to no buried treasure and revealing no long-forgotten secret,  somehow survived world wars, innumerable storms, and rocks thrown by boys for a century.

Richard Platz’ message.  Posted in a beer bottle on May 17, 1913 and found by German fishermen in 2012–97 years after it was sent via the Baltic Sea.

Not all messages are without consequence.  In May 2005 eighty-eight shipwrecked migrants were rescued off the coast of Costa Rica. They had placed an SOS message in a bottle and tied it to one of the long lines of a passing fishing boat. Good thing for them that the age-old art of communication via message in a bottle is still alive.

Bottled-message Technology Is Not Dead

In case you think message-in-a-bottle technology is obsolete, consider the familiar pneumatic tube that we use every day in banks and many other venues.  The pneumatic tube is clearly nothing more than a modern-day adaptation of the old message-in-a-bottle technology.  I, Tiger Tom, declare that without the pioneering bottle tossers from Theophrastus on, the modern pneumatic tube would not have been invented and bank tellers would be delivering cash to drive-through customers on roller skates.

Advantages of Bottle Messaging

It’s clear that communication via bottle-encapsulated letters has some limitations. It’s usually pretty slow, it’s hard to target accurately, and it doesn’t work well at all in rivers unless the addressee is downstream.  Also, it is excruciatingly slow during winter in cold climates.

But it also has advantages.  The cost is low, with no transit fees and product cost if recycled paper and bottles are used. No taxes. Bottle-messaging is also very low-tech and easy to learn, with no passwords, encrypting, or software upgrades to contend with. No batteries required.  Although you can write anything you want in a bottle message, the format does not encourage stupidities like LOL  and OMG.  That’s because when you write for the bottled delivery system you are aware that your message might be read 97 years hence, so the gravity of the situation demands that the writer show a bit more class than would be expected in a texted message telling a friend that you’re waiting in line at the supermarket. The message that Richard Platz sent, for example, was eventually delivered to his granddaughter. Imagine how you’d feel if your great-grandson, not even born yet, were to get from his great grandma a silly epistle peppered with OMGs and NBDs.

Also, consider the health advantages of the message-in-a-bottle system.  Not only does it get you off your rump and away from the computer, it requires you to walk to the lake or river to post the message, then make a daily return, probably for the rest of your life, to walk the shore looking for your answer. Sending one message could turn into a life-long exercise program.

And consider environmental  advantages which include no greenhouse gas emissions and a carbon footprint of zero. The revival of bottled messaging could provide a valid reuse for the countless used catsup bottles that go to the dumps daily. Remember that reuse is better than recycling.

Finally,  just think how much saner our world would be if mad politicians gave up Twitter and posted their random ravings via bottles in the sea.

Common drugs affecting plant growth,  study shows

Water Woes Among Topics for 8 Governors in Vegas

by Ken Ritter

Facing dwindling water supplies, Western states are struggling to capture every drop with dam and diversion projects that some think could erode regional cooperation crucial to managing the scarce resource.

Against that backdrop, eight Western governors meeting in Las Vegas this weekend will address regional water issues, and water managers from seven states arrive next week to work on ways to ensure 40 million people in the parched Colorado River basin don’t go thirsty.

Gary Wockner, a conservationist with the Denver-based advocacy group Save the Colorado, said there’s already jostling amid the fear of empty buckets. “Everyone is trying to get the last legal drop of water,” he said.

Colorado River Water Users Association representatives deny there’s discord at their table.

“Fifteen years of drought has tightened everything. But I don’t see this as people are getting ready to fight,” said Jeff Kightlinger, general manager of the Metropolitan Water District of Southern California. That agency is dealing with a double-whammy ? drought on the Colorado River and in the Sierra Nevada and Northern California.

Nevada Gov. Brian Sandoval will host Western Governors’ Association counterparts from Colorado, Idaho, Montana, New Mexico, South Dakota, Utah and Wyoming this weekend to consider several issues, including water. Two days of drought workshops follow.

“The motto is: We save the system as a whole,” said Pat Mulroy, longtime general manager of the Southern Nevada Water Authority in Las Vegas and now a senior policy fellow with the Brookings Institution.

“If we get into, ‘I’m going to win,’ and, ‘You’re going to lose,’ there won’t be a winner,” Mulroy said.

But Wockner said Colorado, Wyoming and Utah are considering dams and diversions in the mountains to capture water they’re entitled to before it reaches the Colorado and flows to the deserts.

New Mexico has plans to divert and store water from the Gila River for cities and farms before it flows into Arizona and empties into the Colorado River near the Mexico border.

“Diversions extract water from the system,” said Jack Schmidt, professor of watershed sciences at Utah State University. He just completed three years studying the Grand Canyon for the U.S. Geological Survey. “More water use and more water retention in the upper basin means less water flowing through the Grand Canyon to the lower basin.”

Schmidt referred to the Colorado River Compact of 1922 and agreements with Mexico that promise about 16.5 million acre-feet of water annually from a river system that has historically taken in about 15 million acre-feet from rainfall and snowmelt. But that amount has diminished during almost 15 years of drought. One acre-foot of water is about enough to serve two average Las Vegas homes for a year.

“You could say that we decided how to divide the pie, but the pie is smaller than anybody thought,” Schmidt said. “With climate change, it is even smaller than that.”

In Las Vegas, which virtually relies on water from Lake Mead, officials are making plans to add a $650 million pumping facility to draw from the reservoir even if levels drop below 1,000 feet above sea level. That’s the line at which Hoover Dam’s hydroelectric turbines would be idled.

The Southern Nevada Water Authority already is drilling an $800 million tunnel to tap water from the bottom of the lake, at 860 feet above sea level.

At 900 feet ? so-called “dead pool” ? the river would end at Hoover Dam. Nothing would flow downstream.

The lake reached its high water mark in 1983 at 1,225 feet.

The Metropolitan Water District’s Kightlinger said the seven basin states ? Colorado, Utah, Wyoming and New Mexico upstream and California, Arizona and Nevada downstream ? have a history of cooperating, and they have forged several landmark agreements.

A 2012 amendment to a 70-year-old treaty between the U.S. and Mexico has the river flowing south of the border again.

Last summer, water agencies in Denver, Los Angeles, Las Vegas and Phoenix began an $11 million pilot program with the federal government to pay farmers, cities and industries to cut use of Colorado River water.

The goal is to prop up Lake Mead, which stood Friday at 1,084 feet above sea level ? just 9 feet above the crucial 1,075 level that would trigger cuts to Arizona, Nevada and California.

The federal Bureau of Reclamation this week projected a better than 50 percent chance that it will declare such a shortage in January 2017.

The Central Arizona Project would face the first cutbacks, and farmers would be hit hardest, agency chief David Modeer said.

“Hoping for snowpack is not sufficient to solve this,” Modeer said. “It’s going to take cooperation and sacrifice among all of us to stave off disaster in the river.”

Source: ABC News.

Pure Water Gazette Fair Use Statement

Avoid Amazon’s “Cyber Monday,” and buy local

by Jim Hightower

It’s “Cyber Monday” – get out there and buy stuff!

But you don’t actually have to go anywhere, for this gimmicky shop-shop-shop day lures us to consume without leaving home, or even getting out of bed. Concocted by Amazon, the online marketing monopolist, Cyber Monday is a knock-off of Black Friday – just another ploy by Amazon CEO Jeff Bezos to siphon sales from real stores.

Seems innocent enough, but behind Amazon’s online convenience and discounted prices is a predatory business model based on exploitation of workers, bullying of suppliers, dodging of taxes, and use of crude anti-competitive force against America’s Main Street businesses. A clue into Amazon’s ethics came when Bezos instructed his staff to get ever-cheaper prices from small-business suppliers by stalking them “the way a cheetah would pursue a sickly gazelle.”

Jeff Crandall, who owns Old Town Bike Shop in Colorado Springs, is one who’s under attack. He offers fair prices, provides good jobs, pays rent and taxes, lives in and supports the community. But he has noticed that more and more shoppers come in to try out bikes and get advice, yet not buy anything. Instead, their smartphones scan the barcode of the bike they want, then they go online to purchase it from Amazon – cheaper than Crandall’s wholesale price. You see, the Cheetah is a mulitibillion-dollar a year beast that can sell that bike at a loss, then make up the loss on sales of the thousands of other products it peddles.

This amounts to corporate murder of small business – and, yes, it’s illegal, but Amazon is doing it every day in practically every community. So, on this Cyber Monday, let’s pledge to buy from local businesses that support our communities. For information, go to American Independent Business Alliance: www.amiba.net.

Source: “Amazon’s ruthless practices are crushing Main Street–and threatening the vitality of our communities,” www.hightowerlowdwon.org, September 2014.

Radon In Water:  How it gets there and How to Get Rid of It

 Radon is one of the more perplexing and misunderstood issues in home water treatment.  The material below is excerpted from several sources, especially from an excellent Penn State University Extension services publication.

Radon is a colorless, tasteless, odorless, radioactive gas. It is formed from the decay of radium in soil, rock, and water and can be found worldwide.

The radon in the air in your home generally comes from two sources: the soil or the water supply.  It escapes from the earth’s crust through cracks and crevices in bedrock, and either seeps through foundation cracks or through poorly sealed areas into basements and homes, or it dissolves in the groundwater. Radon can be trapped in buildings where it can increase to dangerous levels. Radon entering your home’s air supply through the soil is typically a much larger risk than the amount of radon   In general, radon is of much greater danger when it enters through the soil than when it enters via the water supply.

Radon can be inhaled from the air or ingested from water. Inhalation of radon increases the chances of lung cancer and this risk is much larger than the risk of stomach cancer from swallowing water with a high radon concentration. Generally, ingested waterborne radon is not a major cause for concern. The extent of the effects and the risk estimates involved are difficult to determine. According to the EPA’s 2003 Assessment of Risks from Radon in Homes, radon is estimated to cause about 21,000 lung cancer deaths per year. The National Research Council’s report, Risk Assessment of Radon in Drinking Water, estimates that radon in drinking water causes about 160 cancer deaths per year due to inhalation and 20 stomach cancer deaths per year due to ingestion.

Radon in water usually originates in water wells that are drilled into bedrock containing radon gas. Radon usually does not occur in significant concentrations in surface waters.

Dissolved radon in groundwater will escape into indoor air during showering, laundering, and dish washing. Estimates are that indoor air concentrations increase by approximately 1 pCi/L for every 10,000 pCi/L in water. For example, a water well containing 2,000 pCi/L of radon would be expected to contribute 0.2 pCi/L to the indoor air radon concentration. Based on the potential for cancer, the EPA suggests that indoor air should not exceed 4 picocuries per liter (pCi/L).

EPA and various states have recommended drinking water standards for radon in water ranging from 300 to 10,000 pCi/L but no standard currently exists. One study of radon present in over 900 Pennsylvania water wells found that 78% exceeded 300 pCi/L, 52% exceeded 1,000 pCi/L and 10% exceeded 5,000 pCi/L.

Since most exposure to radon is from air, testing of indoor air is the simplest method to determine the overall risk of radon in your home. Test kits for indoor air radon are inexpensive and readily available at most home supply stores.

Testing for radon in water is also inexpensive but requires special sampling and laboratory analysis techniques that measure its presence before it escapes from the sample. Test kits are available from various private testing labs

The presence of waterborne radon indicates that radon is probably also entering the house through the soil into the basement which is generally the predominant source. Therefore, treating the water without reducing other sources of incoming airborne radon probably will not eliminate the radon threat. Therefore, you should also test the air in your home for radon.

Treating Radon in Water

The main objective of water treatment is removing radon from water before the radon can become airborne. Most water treatment, therefore, focuses on “point of entry” rather than “point of use.”

Granular Activated Carbon (GAC)

One method for removing radon from water is with a granular activated carbon (GAC) unit. Although these systems come in a variety of models, types and sizes, they all follow the same principle for removal . The standard radon GAC filter is a tank-style unit that can have either a backwashing control or a simple non-backwashing head. Non-backwashing GAC units must be protected from sediment with a prefilter.  Radon filter sizing depends on the amount of radon present, service flow rates, amount of water treated, the size of the treatment bed and other factors, so each application must be considered separately and radon testing for effectiveness of the filter should be carried out regularly.

Typical setup for a GAC filter treating radon.

Various estimates suggest that GAC should only be used on water supplies with a maximum radon concentration of less than 30,000 pCi/L.  If you do decide to purchase a unit, select a filter size that matches your water use and conditions.  According to EPA, a three-cubic-foot unit can handle as much as 250 gallons of water per day and effectively reduce radon levels. Typical water use in the home ranges from 50 to 100 gallons per person per day.

A major drawback to the use of GAC filters for radon removal is the eventual buildup of radioactivity within the filter. For this reason, the GAC unit should be placed outside the home or  in an isolated part of the basement to minimize exposure. The carbon may also need to be replaced annually to reduce the hazard of accumulated radioactivity. Spent GAC filters used for radon removal may need special disposal.  Disposal of spent carbon should be in compliance with local waste disposal regulations.

GAC treatment units are frequently also installed to remove chlorine, pesticides, petroleum products, and various odors in water. In these cases, the GAC filter may unknowingly be accumulating radioactivity as it removes radon from the water. Radon should always be tested for and considered as a potential hazard with the use of GAC filters.

Aeration

EPA has listed aeration as the best available technology for removing radon from water. Home aeration units physically agitate the water to allow the dissolved radon gas to be collected and vented to the outside. With new technological advancements in home aeration, these units can have radon removal efficiencies of up to 99.9%. Standard aeration treatment units typically cost $3,000 to $5,000 including installation.  Be aware that aeration specifically for radon reduction is not the same as aeration for iron or hydrogen sulfide reduction.  While “closed tank” systems designed for iron and sulfide reduction might help with radon, they are not designed to provide the large ventilation capacity needed to assure release of radon to the atmosphere.

When considering installation of aeration units, other water quality issues must be taken into account, such as levels of iron, manganese and other contaminants. Water with high levels of these types of contaminants may need to be pre-treated in order to prevent clogging the aeration unit. Disinfection equipment may also be recommended since some aeration units can allow bacterial contamination into the water system.

Typical Spray Aeration System Designed  for Radon Reduction in a Private Home

There are several styles of aeration treatment units but all work on the same principle of aerating or agitating the water to allow the radon gas to escape so it can be captured and vented. Each type of unit has advantages and disadvantages. One of the more common styles is a spray aeration unit shown above. In this case, water containing radon is sprayed into a tank using a nozzle. The increased surface area of the sprayed water droplets causes the radon to come out of the water as a gas while the air blower carries the radon gas to a vent outside the home. About 50% of the radon will be removed in the initial spraying so the water must be sprayed several times to increase removal efficiencies. To keep a supply of treated water, a 100-gallon or larger holding tank must be used.

Another common aeration unit is the packed column where water moves through a thin film of inert packing material in a column. The air blower forces radon contaminated air back through the column to an outdoor vent. If the column is high enough, removal efficiencies can reach 95%.

Another type of aeration system uses a shallow tray to contact air and water. Water is sprayed into the tray, and then flows over the tray as air is sprayed up through tiny holes in the tray bottom. The system removes more than 99.9% of the radon and vents it outside the home.  Go here for illustrations of other aeration systems.

See also:  the EPA publication and a list of resources from RadonResources.com.

Main Source:  Penn State University.

Pure Water Gazette Fair Use Statement

Pollution total dumped in lake hits 3.7 billion gallons

by Chad Selwesky

The rain showers of Sunday and Monday created sewage overflows that dumped 79 million gallons into Lake St. Clair, bringing the total pollution this year from sewer systems discharged into the lake to 3.7 billion gallons.

The GWK Drain in Oakland County released 72 million gallons, and the Chapaton sewage basin in St. Clair Shores spilled another 7 million gallons. Both facilities partially treat their discharges by adding chlorine and removing solid waste before releasing them into the waterways.

Brent Avery, operations manager at Chapaton, said the situation could have been worse, as the nearby Martin retention basin and the windy weather also presented concerns.

“We filled to the brim at Martin (basin), but did not discharge” Avery said. “We did not experience a power outage, but it was sure fluctuating.”

The 2014 totals reflect the massive sewage dumping on Aug. 11-12 during the unprecedented flooding experienced across southern Oakland and Macomb counties.

During that time period, the GWK Drain, traditionally known as the Twelve Towns Drain, flushed 2.1 billion gallons of partially treated sewage and rainwater into Macomb County’s Red Run Drain at Dequindre, south of 13 Mile Road. From there, the contaminants flow through residential neighborhoods to the Clinton River and then out to Lake St. Clair.

The Chapaton system, located at 9 Mile Road and Jefferson and operated by the Macomb County Public Works Commissioner’s Office, spewed 166 million gallons when the floodwaters hit.

In addition, the amount of untreated raw sewage dumped into the waters by Macomb County communities during the flood was raised dramatically in the final numbers, from nearly 6 million gallons to 140 million gallons.

At one point earlier this fall, officials estimated that the county’s pollution total would hit 4 billion gallons by the end of the year. Sewage system officials say that the overflows are diluted by rain water and present no danger to the public. At the same time, environmental activists say the E. coli bacteria in the discharges is the main cause of the hundreds of beach closings on Lake St. Clair over the past several years.

Water tainted with E. coli can cause skin rashes, nausea, vomiting or diarrhea and it can lead to exposure to viruses.

The total number of gallons dumped into the lake this year equals the volume of 5,300 Olympic-size swimming pools.

Source: Macomb Daily.

Pure Water Gazette Fair Use Statement

No Black Friday

Pure Water Products is following its Black Friday closing policy occasioned by a shopping accident sustained during the 2012 shopping season.  Please read details. The company’s retail store in Denton, TX will reopen for business as usual on Saturday December 29.