Water Conditioning & Purification Magazine

People

Saturday, July 20th, 2002

Water industry veteran, WC&P friend passes away: Stan Ziarkowski
Stanley M. Ziarkowski, of Mount Laurel, N.J., died May 3. He was 68. Ziarkowski was recently honored by Sybron Chemicals Inc., of Birmingham, N.J., as a Quarter Century Safety Club Charter member. He spent 36 years at the company. Most recently, he was vice president of the Household Ion Exchange Group. Earlier, he worked with Sybron’s Gamelen Group as laboratory chief and, in 1986, was named vice president of sales for its Ionac Group, which later became the Household Ion Exchange Group. Bayer Corp. bought Sybron in September 2000.

A well-known figure in ion exchange, “Stan” worked with many others just as well known and with roots at Sybron and its predecessor Permutit (which was the first American company to market a softening zeolite in 1913). They include ResinTech’s Mike Gottlieb; Wes McGowan, author of the WQA Glossary of Terms and a number of training manuals for the Water Quality Association; Al Preuss, president of Aldex; and Don Brodie, co-owner of Purolite; and Frank McGarvey, retired.

Said Gottlieb of Ziarkowski: “A lot of people are celebrated in death. Some shone brighter in life. Some less. His light was worth the celebration. Some people are witty, some are friendly, some are intelligent—Stan was all of those things and always charitable. There wasn’t a level he couldn’t reach (down) to or up to.”

A longtime WQA member, Ziarkowski served on the WQA Board of Directors (1992-95), the Board of Regents (1996-2002), and numerous committees and task forces, most notably science advisory, ion exchange and educational services. He received the association’s Award of Merit in 1993, Regents Award in 1997 and was named to the Hall of Fame in 1999.

He was also very active in the Eastern Water Quality Association, which he served as president (1998-99) and as a board member (15+ years). Former EWQA director Carol Russell, president of Water Treatment & Accessories, said Ziarkowski was the “dad” of the eastern chapter. Both stepped down on Sept. 11 of last year.
“In meetings, as debates would get rolling, I’d watch Stan’s face and as soon as he began to speak, everyone else would quiet down. Nobody ever talked over Stan. You listened. That’s how you learned,” she said. “I came to count on his wisdom on many occasions.”

Ziarkowski held a patent for an inert resin that’s used to separate cations from anions in a mixed bed deionization unit. His work on a wide range of water treatment issues was published in several industry publications. That includes WC&P, which he also served as a member of its Technical Review Committee (1999-2000) and its predecessor Advisory Committee (1989-90).

“Stan’s been a great friend to WC&P and has written for us for years,” said Sharon Peterson, president of Publicom Inc. “We’ll sorely miss him.”

Ziarkowski attended Penn State University, where he earned a bachelor’s degree in chemistry.
“A lot of times at industry events and meetings, he’d try to get out on Fridays because he was such a loyal Penn State fan. He went to every game he could, bar none,” Preuss said. “He was a great guy and it’s a heck of a loss for all of us. It’s a loss for the water treatment business. We all loved him.”

Surviving Stan is his wife of over 50 years, Evelyn, and their two daughters, Donna and Carol Anne, and two grandchildren, Bret and Victoria.

Condolences can be sent to Mrs. Ziarkowski at 132 Briarwood Road, Mt. Laurel, NJ 08054. Memorial contributions can be made to the American Cancer Society, 1851 Old Cuthbert Road, Cherry Hill, NJ 03034.
Additional contributions can be made in his name to the Water Quality Research Council. Contact the WQA at (630) 505-0160.


Hervey to direct new office
WEDECO Ideal Horizons has opened a new Latin America office in Buford, Ga. Eugene Hervey, sales manager for Latin America, will head up the office. Hervey is fluent in Spanish and has experience offering technical service of applications, sizing, installation and sales of WEDECO Ideal Horizons UV disinfection equipment for various industrial applications. WEDECO Ideal Horizons uses UV technology for disinfection, destruction of ozone and total organic carbon.

Horner joins Topway team
Topway Global Inc., of Brea, Calif., welcomes Jerry Horner as operations manager in charge of point-of-entry water conditioning. This new division will concentrate on residential and commercial water softeners and filters. This line of products will be in addition to the company’s point-of-use reverse osmosis and filtration equipment. Horner is a certified water specialist, level 6, and has more than 16 years of sales, service and installation experience in the water conditioning industry.

Manager tabbed at CWQA
Effective April 1, Constance Wrigley-Thomas assumed the role of program manager for the Canadian Water Quality Association (CWQA). Previously, Wrigley-Thomas was the marketing and communications manager for the Canadian Health Record Association. Other members of the CWQA include Ralph Suppa, government affairs; Lou Smith, technical consultant; Ron Courtney, bookkeeper; Isabel Brisbois, administrative assistant; and Maggie Ages, receptionist. In her new position, Wrigley-Thomas will report to the CWQA Board of Directors and will be responsible for membership, CWQA professional certification and consumer inquiries. Wrigley-Thomas succeeds Suppa, who is the president-elect of the Canadian Institute of Plumbing and Heating, the managing association of the CWQA. The association’s members are encouraged to contact Wrigley-Thomas at wrigley-thomas@cwqa.com or (416) 695-3068.

McCarthy becomes president
Black & Veatch Corp., of Kansas City, Mo., appointed Dan McCarthy as president of the company’s Water Americas Division. McCarthy will replace Jim Patton, who is retiring in August. Previously, McCarthy was senior vice president and Midwest region manager for the Americas Division. His primary areas of responsibility have been in water supply, treatment and distribution projects from planning through design and construction. He received a bachelor’s degree in civil engineering from Iowa State University and his master’s degree in civil engineering from the University of Kansas.

VP post goes to Calabria
William Calabria has been announced as vice president of the commercial division of Diamond Water Conditioning, of Hortonville, Wis. He has more than 29 years of experience in the water treatment industry.

NWRI awards annual prize
The National Water Research Institute (NWRI) announced that Harry Ridgway, Ph.D., is the recipient of the Athalie Richardson Irvine Clarke Prize for excellence in water research. NWRI established the prize in 1993 to award outstanding research scientists who have implemented better water-science research and technology. The prize, which includes a gold medallion and $50,000 award, is presented annually. For 25 years, Dr. Ridgway has pioneered significant studies on membrane technology, particularly the discovery of the crucial role that microorganisms play in purifying water and wastewater. He received a bachelor’s degree in microbiology/chemistry from California State University and a doctorate degree in marine microbiology from the University of California. He has been research director at the Orange County Water District since 1981.

Ondeo makes staff changes
Ondeo Nalco announced Mike Kahler as group vice president and president of the company’s industrial division. The industrial division includes automotive, chemical processing, global mining, primary metals, refining and petrochemicals, utilities and paper industries. Prior to his appointment, Kahler headed the company’s specialty division. Matt Knight, who formerly headed the industrial division, has assumed the position of group vice president, sales force optimization. Ondeo Nalco is a subsidiary of Ondeo, the water division of SUEZ.

Novazone appoints 2 staff
Novazone Inc., of Livermore, Calif., named Mike Borel as president and CEO. Previously, he was president and COO of Valent Corp. Meanwhile, Chris Hubbard was named the company’s regional accounts manager for the eastern United States. Novazone is involved in the design, sales and service of ozone solutions.

Ask the Expert

Saturday, July 20th, 2002

The long and short of softening

Question: Could you please explain why water treated by a softener typically will show an increase in sodium, and a decrease in chlorides, when softener salt is composed of sodium chloride? Thank you.

Larry C. Aldridge
Hartville, Ohio

Answer: A “short” answer for you might be that, in the ion exchange process, softeners/conditioners use saltsodium chloride (NaCl) or potassium chloride (KCl)—to regenerate the resins that remove contaminants from the water stream. This is done by ionic selectivity based upon the electronic charge or valence of the compounds being removed, which are “attracted to” or “regenerated off” of a resin bead. As the bead loads up with contaminants that are adsorbed or absorbed onto it, sodium or potassium is released from the bead in “exchange” for the undesirable element. Don’t forget, this is in very small quantities. When the softener is regenerated, water from a brine tank containing pellets of salt—NaCl or KCl—is flowed through the resin bed and, because of the concentration, the undesirable contaminants are “backwashed” off of the resin in exchange for the Na or K part of the salt. The chlorides also are sent to waste in the backwash water. I believe that provides the simple answer to your question, even if it’s not short. Keep in mind, the longer answer is more complicated and requires a broader understanding of water chemistry.

Reducing septic system impacts

Question: I am trying to determine which way to go: water softener or purifier of some sort.

Our problem is hard water, which is not affecting much of anything except our skin after showering, my wife’s hair and some items in the wash (despite use of Downy and other similar products). We are on a septic/leach field system so we do not want to use backflushing systems, and I am a bit concerned about use of salt in this system also (fear of killing those nifty little enzymes). I am not sure if the latter is a legitimate concern or not.

This is a small population area and providers seem to be Kinetico, Culligan and Sears. I do not really trust the sales people as they are there to sell their products only and may not even know the full story of water conditioning. So far, I have been unable to find any publications that are definitive. I’m hoping you can steer me in the right direction. Thank you.

Dennis Jones
Stevensville, Montana

Answer: Extensive studies have indicated that the brine from water softeners will not have a significant effect on septic systems. Keep in mind that watching your use of detergents, cleaners, shampoos, soaps and other items that may go into your septic tank via shower, laundry, dishwasher or garbage disposal can sharply reduce the load you put on your system. These can be significantly more damaging than softener discharge. Opt for more “natural” low-phosphate, low-chlorides products where possible—and compost waste or put it in the garbage rather than run it down the disposal. With respect to water treatment, I would suggest you try to find someone at a dealership that you feel is technically competent, and whose opinion you trust. Take a little time to get to know them. Research what they tell you. Compare and contrast. Trade journals such as WC&P, as well as the Water Quality Association (www.wqa.org), are committed to providing educational information to readers/members, and many professionals in this industry are knowledgeable and committed to providing objective and accurate information to the consumer.

Global Spotlight

Saturday, July 20th, 2002

Chester Paul Co., of Glendale, Calif., has published its water dealer price catalog. It offers a full line of water filtration components such as USFilter, John Guest, Omnipure, Harmsco, Hydro-Flow, Aquatec, Filmtec, Amtrol, Touch-Flo, QMP, Falcon Stainless, UV systems and accessory items. 💧

ALON USA LP and USFilter Operating Services Inc. have signed a 20-year, $76.6 million outsourcing agreement for water and wastewater services. ALON’s refinery is located in Big Springs, Texas. 💧

After 12 years of use in city and county lift stations in Australia, the Lift Station Well Washer is now available in the United States through an exclusive agreement between USFilter and Global Waste Water Answers LLC. The agreement gives USFilter the sole distribution rights of the well washer in the United States and Canada. 💧

Osmonics Inc., of Minnetonka, Minn., reported sales of $53.2 million for the first quarter ending March 31, almost equal to sales of $53.3 million for the first quarter of last year. 💧

Sandia National Laboratories has selected CH2M Hill, of Denver, as one of 17 firms to be licensed to train water utilities, consultants and others in Risk Assessment Methodology for Water Utilities. 💧

Kansas City, Mo.-based Black & Veatch was selected to lead an international stormwater research team in a $690,000 study of Best Management Practices and Sustainable Urban Drainage Systems in the United States and United Kingdom. 💧

NSF International, of Ann Arbor, Mich., released a new verification report and statement for the ETV Drinking Water Systems Center—the Pall Corporation Microza™ Microfil-tration System Module. This report is located on the NSF and USEPA websites, www.nsf. org/etv.dws or www.epa.gov/etv 💧

CUNO Inc., of Meriden, Conn., reported second quarter results for the period ending April 30. Worldwide sales were $63.1 million, up 5 percent vs. that period last year. 💧

Hughes Supply Inc., of Orlando, Fla., opened a new location in May in Fort Collins, Colo. The branch will supply water and sewer products to contractors for use in commercial, residential, infrastructure and industrial projects. With annual revenues of $3 billion, Hughes has 439 locations in 34 states and Mexico. 💧

Bohus, Sweden-based Eka Chemicals Inc. acquired a patent to a process using a hydrogen peroxide/alkali metal chlorate blend as a feed chemical for the production of chlorine dioxide. It’s used in applications that include drinking water treatment, wastewater treatment, cooling tower treatment and industrial process water treatment. 💧

Vista, Calif.-based Glacier Water Services Inc. said revenues for the quarter ending March 31 increased 14.7 percent to $15.41 million as compared to the same quarter a year ago. 💧

Long Beach, Calif.-based Aquatyzer Engineering Inc. acquired the Internet domain of Bottlingplant.com. All Internet traffic to the site will be redirected to Aquatyzer.com. Aquatyzer is an engineering design, manufacturer and distributor of water purification and bottling equipment and systems. 💧

Clearwater Station Inc., of Lampasas, Texas, was selected as the newest dealer in central Texas for Everpure water filtration products. Clearwater has water retail stores in Lampasas, Burnet and Harker Heights. 💧

Met-Pro Corp., of Harleysville, Pa., acquired Pristine Hydrochemical Inc., of Williston, N.D. Pristine sells water treatment chemicals and services to municipal water utilities. Met-Pro also reported first quarter sales of $16.2 million compared to $17.6 million for that period last year. 💧


Pentair rolls out several new products
Pentair/Structural introduced four new products at the Water Quality Association trade show in New Orleans in March. The first is a heavy duty brine tank for residential water softeners with better structural integrity and allows a greater ability for product bundling to reduce shipping costs. A new thermoplastic tank and DI exchange tank are both impact and chemical resistant, which offers a longer service life. Finally, the new Soft Flo™ water softener cabinet is specially designed for Fleck mechanical 5600 and electronic 5600SE and ProFlo valves. The appliance-style cabinet fits 8-inch, 9-inch or 10×35-inch Structural vessels and also serves as a brine tank. “It’s basically priced for the dealer who has to compete with mass retail,” said Albin Erhart, marketing communications manager for the Brookfield, Wis., company.

New Pentair/Fleck valve options include a double backwash cam that adds a second backwash cycle between the slow rinse and rapid rinse cycles on Fleck’s 5600SE, 6600 and 6700 residential down-flow valves for water softeners and filters. This extends the media lifecycle and reduces the need for prefiltration, particularly benefiting well water applications with higher suspended solid concentrations that may require additional backwashing. Fleck also introduces a 1-¼-inch brass yoke for quick connects of 1-¼-inch plumbing to the Fleck standard 2-inch center without additional plumbing, and it showcases a new stainless steel bypass.

A new valve introduced at the WQA show allows for upscale homes with larger piping, combining capabilities of Fleck and SIATA, Pentair’s European brand originating in Italy. The Siata V132SE is designed for newer home construction that uses larger amounts of water for a variety of uses, whether pool, spa, hot tub or multiple bathrooms.

For the commercial/industrial market, Pentair will introduce in August an electronic network controller for the next generation in electronic controls. Only one controller is needed for a variety of uses. “These are single, double, triple and quadruple-valve systems all built the same just programmed differently on each valve. They come pre-programmed or can be programmed on site. But they make installation much easier and you don’t necessarily need an electrician,” Erhart said.

Lastly, Pentair is now working on another new 35-gpm residential valve to be launched next year that will be one of the highest flow valves available on the market, but uses 50 percent fewer parts. It will have a backwash rate of 35 gpm and can be used for softeners and filters.

Purolite conviction on Cuba overturned
A U.S. District judge on June 3 tossed out a jury verdict against Purolite chief executive Stefan Brodie, acquitting him of charges of conspiring to trade with Cuba, the Philadelphia Daily News reported. The judge cited “insufficient evidence” as the reason for overturning the early April conviction against the co-owner of the Bala Cynwyd, Pa.-based company, which makes and sells ion exchange resins used worldwide in water treatment systems. Arguments are still being heard in an appeal of convictions against Brodie’s brother and partner, Donald Brodie and the company’s  marketing director James Sabzali, a Canadian citizen.

Sources close to the case noted, of remaining individual charges for which there were convictions (roughly half the initial charges were deemed without merit), most involve simply signing off on expense reports. For instance, half of those against Sabzali involve transactions when he lived in Canada and half involve expense reports he signed for another Canadian citizen’s travel to Cuba. This raised the ire of the Canadian government particularly since it has a law against honoring the U.S. embargo—viewed there and in Europe as an extraterritorial extension of U.S. law.

Sta-Rite makes purchase
Sta-Rite Industries, of Delavan, Wis., acquired Aermotor Pumps Inc., of Conway, Ark., in late April. Sta-Rite
purchased the company from GSW Inc., a manufacturer of durable goods and products based in Ontario, Canada. Aermotor manufactures a full line of water pumps and pump accessories for a variety of applications including potable water, agriculture and irrigation, sump drainage, sewage and effluent for the residential, industrial, commercial and mining markets. Sales last year totaled $50 million, and the company exports to more than 20 countries worldwide. Besides its main plant in Arkansas, Aermotor also has branch offices in Longwood, Fla.; Portland, Ore., and Canada. The company will become part of Sta-Rite’s Water Systems group. Sta-Rite is a worldwide manufacturer of both water pumps and water processing equipment for the water systems, irrigation, pool/spa and filtration markets.

UV system to treat NDMA
On March 11, the Orange County Water District Joint Cooperative Committee for the Groundwater Replenishment System Project recommended the use of Trojan UV equipment for the undertaking near Los Angeles. The UV equipment will form part of a larger system that will initially treat a flow rate of approximately 70 million gallons of water per day. The system will be used to greatly reduce N-nitrosedimethylamine (NDMA) as well as to ensure complete disinfection of the treated flow prior to groundwater recharge.

Farm bill helps wells
The farm bill signed into law in mid-May by President Bush includes a provision that would assist low to moderate-income Americans fund the installation or improvement of individual household water wells. The provision authorizes $10 million for grants for each year between 2003 and 2007. The grants would go to non-profit organizations to provide loans to individuals for constructing, refurbishing or servicing household water well systems. The loans would have a maximum interest rate of 1 percent with a term up to 20 years. Though it makes up a very small portion of the $31.2 billion farm bill, it’s viewed as an important step in offering a choice to rural residents to gain access to safer drinking water. The bill was endorsed by the National Ground Water Association. The full text of the household water well financing is available from the government affairs pages on NGWA’s website, www.ngwa.org/govaffairs/legis.html, or by calling (800) 551-7379.

WEDECO lands Fla. ozone deal
PCI-WEDECO, of West Caldwell, N.J., installed an ozone generation system for drinking water in a Gulf Coast municipality in Florida. The project included two Effizon ozone generation systems, each capable of producing 35,000 pounds per day (66 kilograms per hour) of ozone. The ozone system will be able to produce from 7,000 to 10,000 pounds per day (190 kg/h) at high concentration reaching 10 percent by weight, using oxygen as the feed gas to maximize performance. This system will treat 100 million gpd of water.

Haliant gets new facility
Haliant Technologies relocated its office and factory to a larger facility in Venice, Fla., on May 6. The facility represents an expansion of over 50 percent from the previous headquarters in Sarasota. “This move is really a morale and productivity booster for our employees, most of whom previously worked at Environmental Products USA and live in the Venice area,” said Ed Closuit, Haliant president. Telephone and fax numbers remain unchanged.

Osmonics plans expansion
Sensing increased demand for reverse osmosis (RO) treated bottled water, municipal water, seawater desalting and general industrial water treatment, Osmonics Inc., of Minnetonka, Minn., has planned a state-of-the-art RO membrane and spiral-wound element factory. It will encompass a 60,000-square-foot expansion of the company’s headquarters. Expansion will increase the total size of the facility by almost 20 percent, and the equipment should be fully operational by 2004. In other news, the company said its Rockford, Ill. facility completed registration of its quality system to the International Organization for Standardization (ISO) 9001 series standards for quality through TUV Rhein-land North America. This certification adds AquaMatic branded products to the extensive list of company products manufactured in ISO 9001 certified plants including valves, controls, filters and RO membranes.
Harrison visits with WRI

Water Resources International (WRI) welcomed Joe Harrison, WQA’s technical director, to its headquarters in Phoenix. Harrison was in town for the water quality technology seminar, which took place on May 16 and 17 at Gateway Community College. After touring WRI’s offices, Harrison watched the world champion Arizona Diamondbacks beat the Philadelphia Phillies, 4-2, behind Randy Johnson’s pitching performance.

Bottled water takes off
Many WQA members are contemplating adding bottled water to their businesses. In fact, the WQA convention offered a couple of bottled water seminars to dealers. Meanwhile, the U.S. market for bottled water volume and sales rose to more than 5.4 billion gallons last year—an increase of 10.6 percent over 2000, according to a recent report from Beverage Marketing Corp.  

Watts purchases Hunter
Watts Industries Inc., of North Andover, Mass., acquired Hunter Innovations Inc., of Sacramento, Calif., for $25 million. Hunter was founded in 1995 as a technology development company and has developed a diaphragm seal technology currently licensed by Watts for its backflow prevention product line, a line of automatic control valves, and advances in large backflow prevention device technology. Hunter is shifting from a technology development company to a manufacturing company, and sales during the last year were about $1.5 million. Watts designs, manufactures and sells an extensive line of valves to the backflow prevention, water regulation and control markets, with annual sales of about $575 million.

Calgon brings UV to Canada
Calgon Carbon Corp., of Pittsburgh, announced that EPCOR Water Services will operate two Sentinel UV disinfection systems under license agreements. The systems will treat 140 million gallons of water per day. Calgon Carbon has patented the low-energy ultraviolet light for the inactivation of Cryptosporidium and other pathogens in drinking water that could pose a health threat to people who ingest them. The company offers water producers a license fee to utilize the technology. One of the systems will be installed at EPCOR’s E.L. Smith Treatment Plant, Alberta, Canada. The contract is valued at $800,000. The second system will be installed at the Rosedale Water Treatment Plant, also in Edmonton, within two years. Calgon Carbon said EPCOR will market its systems throughout western Canada.

USEPA mulls over arsenic issue; compliance could be delayed
USEPA officials are considering a plan that would allow smaller water systems (serving less than 3,300 customers) to delay meeting new federal arsenic standards until 2015—even if they supply water with 200 percent of the arsenic limit. Larger systems could even put off compliance for up to eight years with drinking water containing up to 350 percent the legal limit of arsenic. The USEPA National Drinking Water Advisory Council approved the exemption plan on May 8. According to WQANewsFax, the plan would allow small systems providing water with up to 20 ppb of arsenic to delay compliance with the USEPA’s 10 ppb standard for 14 years. It would also allow larger systems providing water with up to 35 ppb until 2009 to comply. An estimated 4,100 of the nation’s 78,000 water systems currently deliver water with arsenic levels above the 10 ppb goal, the vast majority being small water systems in rural states. Many have arsenic levels that significantly exceed the standards, and they cite a lack of funds and infrastructure to clean up their supplies.

IX firm buys General Water
ACM Company Inc., of Forest Hill, Md., a sister company of ResinTech Inc., purchased the EDM business unit from General Water Corp., of Media, Pa. General Water will now devote its full resources to high purity water systems. Terms of the deal weren’t disclosed. ACM will merge the business into its ion exchange resin processing facility in Forest Hill, Md. EDM (electro-discharge-machining) is a precision metal cutting technology that uses ion exchange resin to deionize water that metal parts are bathed in during the cutting process. ACM specializes in the regeneration of ion exchange resins used for EDM, waste-water treatment and resource recovery.

UV laws could pack impact
Pending state legislation that would require UV systems to follow new disposal or labeling laws are being challenged by the industry and other groups, the WQANewsFax reported. If passed, legislation to label UV lamps containing mercury may affect manufacturers. Still, more restrictive legislation on selling and disposing of UV equipment may be enacted, which could adversely affect water equipment dealers and distributors. The measure follows similar action against computer monitor screens and cell phones. Last year, the WQA formed an ad hoc task force to address the mercury-reduction bills pending in several New England states and New York. The WQA has teamed up with other associations such as the National Electric Manufacturers Association to work toward legislation that won’t restrict members’ ability to manufacture, distribute or install UV systems.

Severn wins plant contract
The New York City Department of Environmental Protection awarded Severn Trent Services, of Fort Washington, Pa., a contract for the refurbishment of the 26th Ward wastewater treatment plant in mid-May. The contract is valued at $1.7 million and the project will be completed within one year.

Miox gets certification
Miox Corp., of Albuquerque, N.M., received certification for both its mixed-oxidant and hypochlorite on-site generators for potable water disinfection. The generators are listed under NSF Standard 61, Drinking Water System Components-Health Effects. The certification procedure included a toxicology review to ensure no contaminants were leaching into the drinking water, a factory audit to verify formulation and QA/QC records, and products testing done to NSF protocol.

International

Vivendi continues transition
France’s Vivendi Environnement SA said in late May that it agreed to acquire a 50 percent interest in a Chinese joint venture that will provide drinking water to Shanghai residents. The deal is worth $245 million. The 50-year production, distribution and management contract to provide drinking water to Shanghai’s Pudong district is the first of its kind awarded to a foreign company in China. Vivendi said the contract should generate about $920 million in revenue. In other Vivendi news, the company sold its 17 percent stake in water utility Philadelphia Suburban Corp. The move will generate about $280 million for Vivendi. Chairman Jean-Marie Messier also submitted to his board a plan to sell part of Vivendi Environnement SA to raise cash to pay down Vivendi’s towering debt and secured the board’s backing of the plan in principle. In late May, Vivendi Universal said it looked to raise $2.3 billion by selling shares in its water utility, Vivendi Environnement SA. Meanwhile, Vivendi bought United Kingdom group First Aqua Ltd., parent company of Southern Water, for $3 billion.

Cholera attacks Somalia
More than 50 Somalians died in one week in April from cholera. Dozens more are infected with the disease in both towns and surrounding villages. Around Mogadishu, cholera—an acute bacterial infection that causes severe diarrhea and kills by dehydrating the victim—has been endemic in Somalia for a decade. The country has no state water system and few health facilities.

USFilter finds work abroad
USFilter will install eight LO/PRO odor control scrubber systems and 10 chemical storage tanks for the Mafraq Water Treatment Works, of Abu Dhabi, United Arab Emirates. USFilter’s parent company, Vivendi Water, will provide the facility with several water softeners to prevent scaling and further wear and tear on existing equipment. The installation, valued at $2.7 million, is expected to be completed by early 2003. In other news, USFilter’s John Meunier Products will provide the ValCartier Canadian Air Force Base wastewater treatment plant in Quebec, Canada, with an ESCALATOR screen. The company will also retrofit the Drummondville, Quebec drinking water treatment plant with a high rate clarification process with anthracite gravity filtration units. The project is valued at $2.5 million and was scheduled for completion this month.

Safeway picks Canadian bottler
Canadian-based StonePoint Group Limited has been selected to supply Safeway Inc. with private label spring water for the Denver distribution center. The company also reported fiscal 2001 revenues of $12.04 million, an increase of 4.8 percent over revenues in 2000.

Pepsi bottles up deal
Pepsi Bottling Group Inc. acquired the biggest bottler of Pepsi drinks in Mexico from its two main owners for $1.25 billion in May. The agreement with Pepsi-Gemex SA represents the largest deal to date since becoming a public company in March 1999. Mexico is the world’s second-largest soft drink market, and PepsiCo has been seeking to strengthen its overall position there. Pepsi-Gemex, of Mexico City, is the second-largest bottler of Pepsi drinks outside the United States and owns Mexico’s largest purified water company, Electropura.

UV used for Belgium’s water
WEDECO’s Dutch subsidiary, Helmond-based WEDECO BV, was awarded its third major contract to build a UV drinking water disinfection system by the Antwerp-based water supplier, PIDPA. The drinking water will be disinfected using medium pressure UV technology. PIDPA is one of the three largest water suppliers in Belgium and supplies over 434,000 households in Antwerp. WEDECO AG Water Technology, of Germany, and parent company of PCI WEDECO Environmental Technologies Inc. and WEDECO Ideal Horizons Inc., has decided to consolidate its North American ozone and UV operations into a new single manufacturing, administration and headquarters facility in Charlotte, N.C. Meanwhile, WEDECO AG has won a major contract through its British subsidiary, WEDECO UV Systems. United Utilities, formerly North West Water, has ordered UV wastewater disinfection systems for 19 sewage treatment plants in the northwest of England. In other news, WEDECO AG reported a 113.5 percent increase in revenues in the United States from the first quarter of 2001 vs. the same quarter this year.

SUEZ looks abroad for work
French utility SUEZ SA in mid-May said it won a contract worth $303.9 million to build and operate three water treatment plants in Canada as it seeks to become North America’s biggest player in the sector. In other news, water unit Ondeo signed an agreement to supply and manage the drinking water for Chongquing, in western China. In other news, the French construction, media and telecommunications group Bouygues backed out of talks in early March to trade Saur, France’s third utility company behind SUEZ and Vivendi, to German utility E.ON for the 17.5 percent stake E.ON has in Bouyges’ mobile phone unit. Saur posted a net profit of $30 million in 2001 on sales of $2.26 billion and debt of $613 million. SUEZ saw profits up 12 percent and net income up 8 percent in 2001, but set aside nearly $123 million for potential losses in economically troubled Argentina.

Nestle scoops up company
Nestle AG’s Nestle Waters division bought Sparkling Spring Mineral Water, of Vernon Hills, Ill. Financial terms of the deal weren’t disclosed. Sparkling Spring devotes 85 percent of its business to drinking water to homes and offices, with the remainder the distribution of water at the point of sale. Last year, the company reported sales of $33 million. The deal gives Nestle Waters a 32.5 percent share of the U.S. market, with a portfolio of 15 strong regional brands.

Letters

Saturday, July 20th, 2002

Africa, Americas lose advocates for clean water

Dear Editor:
Today, May 23, is my last day with Water For People. I have been given a wonderful opportunity to pursue a career with GE Capital. Having spent nearly all of the past 12 years working in the non-profit sector, it will certainly be a change of pace; however, the opportunity was more than I could pass up. I greatly value my time spent with Water For People and have been fortunate to have crossed paths with many wonderful, bright, intelligent and giving people along the way. Thank you for your support of Water For People. Until my position is filled, you may direct any questions to Paul Sobiech at psobiech@waterfor people.org. If your question is regarding the Silent Auction, please direct it to Jody Camp at jody@waterforpeople.org, or you may call WFP at (303) 734-3495. Cheers!

Amy Douglas, Fund Raising Manager
Water For People
Denver

Amy:
Sorry to hear about your departure from WFP, but congratulations on winning your new opportunity. It’s been a joy working with you, editorially and personally. Be sure to check this issue for an article from your friend, Karen Zack at Kinetico. It’s a World Spotlight feature on her trip to Central America and a firsthand look at some of the good work you’ve been promoting in Honduras, etc. Let Paul know we’ll be happy to continue touting WFP’s efforts both in Latin America and Africa. The exposure is good for WFP as well as our readers. Good luck in all your future endeavors. Keep in touch.

Carlos David Mogollon
Executive Editor & Editorial Director
Water Conditioning & Purification Magazine/Agua Latinoamérica


Corrections: Table 2 in an article by Frank Bove (“TTHMs, TCE & PCE: Drinking Water Contaminants & Adverse Pregnancy Outcomes,” WC&P, pp. 42-47, May 2002) had a couple errors in column headings. Column 7 should have read “Cardiac defects,” column 8 should have read “Fetal deaths,” and the last column should have read “Spontaneous abortions.”

The number of employees for Erie Water Treatment Controls was incorrectly reported in the May issue (“Executive Q&A: Keeping an Eye on Erie Controls’ Kopacz,” WC&P, p. 78). The company employs 30 people—19 in the United States, 11 in Belgium. This was corrected for the online version of the column.

Cancer Risks from Radon in Drinking Water

Saturday, July 20th, 2002

By Stan Rydell

Summary: While other contaminants, such as arsenic and radium, may have been in the news more frequently in recent months, radon remains of great concern for the water treatment industry. A free software program to assess health risks is available online.


Astudy of radon risks focused on water leads to the conclusion health risks are not so much from the water we drink but more from the water we use. An estimate of radon risk to individuals or groups should consider the sources and pathways of radon in each case so radon reduction plans can be realistically decided upon. Consideration of an individual’s smoking history contributes to the total picture since smoking amplifies radon’s ability to foster lung cancer.

What makes it a health risk?
People generally don’t realize how much potential radon has to cause lung cancer. In reality, it’s far greater than the risk of stomach or other cancer from ingesting radon-bearing water. Most lung cancer victims are smokers, so smoking is assumed to be the primary cause. This may be true, or it may be instead that radon caused the cancer or played a substantial role in its development. Radon-exposed smokers have five times higher risk of lung cancer than a person who never smoked.

The National Academy of Sciences1 and the U.S. Environmental Protection Agency (USEPA) currently estimate that radon (specifically, the radon isotope 222Rn) causes about 18,000 U.S. lung cancer deaths a year, of which about 165 are attributable to water sources (plus about 20 stomach cancers from ingesting waterborne radon). And although the waterborne risk is generally smaller than other sources of radon in indoor air, it’s a greater health risk than that of other regulated drinking water contaminants.

While tobacco smoke is readily identifiable, radon is an invisible but potentially lethal gas whose many isotopes are all radioactive, making it a proven carcinogen like tobacco smoke. Colorless and odorless, radon is produced by its parent, radium, as part of the decay of uranium, an unstable element commonly found in our rocks and soil. In its continuous decay process with a half-life of 4.5 billion years (on its way to reaching a stable state as lead), uranium and its successors discard nuclear particles forming other elements. As they’re created, all these radioactive elements can be released into our water and air.

Lung cancer, the most common radon-related cancer, can be caused by electrically charged alpha particles emitted in the decay of radon. Since radon is constantly decaying, producing progeny and expelling charged particles, these progeny and their successors, which are also decaying, are in our air. When radioactive radon progeny (such as Polonium 210 or Bismuth 214) are breathed in, they tend to stick electrostatically to surfaces like lung tissue. Expelled charged particles passing through matter leave a track of excited and ionized atoms and molecules damaging living lung tissue. Then, if partially destroyed tissue cells don’t correctly repair themselves, cancer can begin.

On the other hand, breathing radon gas (like that released directly into outdoor air from rocks, soil or water) is a much smaller risk. Although radioactive, the inert gas is non-reactive chemically and doesn’t stick to surfaces. It can still enter the bloodstream, however, via the lungs. But for radon dissolved in the bloodstream to have a damaging effect, it must decay while still in the body. Alpha particles from the decay are expelled with high kinetic energy while the emitting nucleus recoils and waits to decay again and again.

Ingested or inhaled radon is known to be promptly removed from the body, and there may also be some protection against cell damage by the stomach’s mucosa as well as absorption by food contained in the digestive system, thus passing some radon and radon progeny from the body harmlessly. With a half-life of 3.82 days, inhaled radon undergoes little decay inside the body, making the risk from inhaled radon progeny about 100 times greater than the risk from inhaled radon.

The risk from our water begins when dissolved radon comes out of solution and transfers to the air. In the home, radon can be released into the air by taking a hot shower, washing clothes or running the dishwasher. Other home uses of water involving less heat, spraying, agitation or volume cause fewer problems. The bottom line is only 11 percent of the water risk comes from ingesting radon-laced water while breathing waterborne radon and its progeny accounts for 89 percent of the risk from radon in water.

Current take on radon
The view of radon in drinking water has changed greatly from the day people used “emanators” to release as high as 2 million picocuries per liter (pCi/L) of radon into their water, believing radon in hot springs had curative powers (see Radon: The Historical View). Today, the USEPA5 has proposed a maximum contaminant level (MCL) of 300 pCi/L. This level, along with an alternative limit (AMCL) of 4,000 pCi/L based on the water equivalent of outdoor air, was recommended in a pending radon rule for public water supplies. This proposed regulation, in what’s described as a multimedia approach, justifies a higher AMCL by requiring risk reduction from non-water sources equal to or greater than what would have been obtained by meeting the 300 pCi/L MCL.

Even this seemingly low level of radon isn’t without risk, which is proportional to concentration; so some level of risk exists until the concentration is zero. If someone ingests and uses water containing 300 pCi/L of radon over a period of 75 years (a risk statistic lifetime), his/her chance of developing radon-related cancer is about 1 in 5,000. At the USEPA’s proposed AMCL, the chance of developing cancer for the same water use period is about 1 in 375.

There has been a growing awareness of radon dangers by health officials, real estate personnel, water system staff and the general public, which led to a moderate level of radon testing of indoor air in the last decade. Today, home inspectors are increasingly testing for radon in indoor air as part of real estate transactions. In some regions, this includes a separate determination for waterborne radon. Radon-releasing water use events (heating, spraying, or agitation of water) in the home, however, often aren’t considered with the other risk factors.

Short-term winter radon detection tests performed in the basement when the house is closed and the heating is on generally reflect the worst case scenario. (For example, suction created by the furnace’s blower depressurizes the basement, drawing radon in through the cracks.) This greatly overestimates radon risk from indoor air since risk is proportional to the annual average radon content of the living areas, not measurable by a one-shot deal in the basement. This results in a pronounced shortfall in the number of cancer cases attributable to soil gas-derived radon when compared to the cancers predicted from this data.

Soil gas-derived risks are largely unique to a specific residence while the water-derived radon risk may be unique to a residence if the water source is a private well. Outdoor air has an average concentration of 0.4 pCi/L, which is overshadowed by the generally higher soil gas radon contribution of several pCi/L to tens of pCi/L. By contrast, water might have a few hundred pCi/L. Groundwater can contain much higher radon concentrations (occasionally millions of picocuries), especially water from bedrock wells produced from granite or other rock types containing appreciable amounts of uranium. Only small, inconsequential amounts of radon are found in surface water, where radon and other gases are able to dissipate.

While radon readily dissolves in groundwater, it can also be readily removed from water to reduce its health risks. This can be done through treatment by highly efficient aeration devices or granular activated carbon (GAC) filters.

Computerized risk assessment
Given the technical aspects and variables involved in calculating radon risks, estimating these risks by hand with any degree of validity is extremely difficult. To make this task easier and less error-prone, a computer is more effective. In one software program, the “Unified Radon Relative Risk Model” (UR3M), a user types in as few as two laboratory-determined values and selects information specific to a particular home. The program calculates the homeowner’s risks, considers cost effectiveness of possible remediation techniques, and/or compares compliance with the USEPA proposed Radon Rule for public water supplies. UR3M and CARBDOSE, a related radon risk program, are available at the USEPA’s Region 1 website.6

UR3M considers the three radon sources, three exposure pathways, specific measured values and the home-owner’s smoking history to arrive at a realistic estimate of the problem. It then presents appropriate risk reduction methods for that case, attainable risk reductions and associated initial cost factors. The result is a personalized, comprehensive assessment of health risks from radon and suggested solutions if indicated. People can then make better-informed decisions with respect to radon reduction. A screen from this program is shown on the next page.

UR3M reports its radon risk calculations with bar graphs as well as numbers for ease of communication. As shown in Figure 1, the program presents a composite picture of that person’s (or household’s) total cancer risk by unifying all air and water radon sources with the individual’s smoking history.

The program can also be used by those exploring risk reduction in multiple homes served by public water supplies by using the “General Population” smoking category, an average of smokers and non-smokers. If a public utility distributes water containing significant amounts of radon to homes that have additional residence-specific radon risks, that is of shared concern between the individual and the public sector.

Conclusion
An understanding of the nature of radon and its health risks is vital in determining what should be done about them. Risk reduction plans can best be based on a comprehensive evaluation of radon risks from all sources. Tools are available at no cost from the USEPA to individuals, water supply personnel and public health professionals for this purpose.

References

  1. National Academy of Sciences-National Research Council, Risk Assessment of Radon in Drinking Water, Washington, D.C., National Academy Press, 1999b.
  2. Thomson, J.J., The Philosophical Magazine, Vol. 4, 1902.
  3. Bumstead, H.A., and L.P. Wheeler, American Journal of Science, Vol. 17, 1904.
  4. Frame, P.E., “Natural Radioactivity in Curative Devices and Spas,” Health Physics, Supplement to Vol. 62, No. 6, June 1992.
  5. USEPA, “National Primary Drinking Water Regulation; Radon; Proposed Rule,” Federal Register, Vol. 64, No. 211, Nov. 2, 1999.
  6. USEPA Region I, Boston, Mass., website: www.epa.gov/region01/eco/wrsdp.html

About the author
Dr. Stan Rydell is with the USEPA, Region I, Office of Ecosystem Protection, Radiation Unit in Boston. He holds a doctorate from Florida State University in geochemistry and radiochemistry, and was an FSU Nuclear Research Fellow at Oak Ridge Institute of Nuclear Studies, Oak Ridge National Laboratory in Tennessee. He developed the Unified Radon Relative Risk Model computer program mentioned here. He can be reached at (617) 918-1637 or email: rydell.stan@epa.gov

A Solution at the Source? Defining & Solving Manure-Borne Pathogen Transmission from Animal Feeding Operations

Saturday, July 20th, 2002

By Jeanette Thurston-Enriquez

Summary: Many water treatment dealers in rural areas may find themselves working with livestock operations, whether that’s in helping them deal with animal waste or in treating feed water with chlorine injectors to improve consumption and the general health of the animals.


The 1998 National Water Quality Inventory surveyed 32 percent of the nation’s waters and reported that 40 percent were considered impaired. Of the impaired waters, 60 percent of rivers and streams and 30 percent of lakes were identified as being negatively impacted by agricultural sources.1 Animal feeding operations (AFOs) have emerged as a major potential source of water pollution with a primary focus on excessive nutrients, especially nitrogen and phosphorus. Human pathogens present in manure, however, are also exposed to the surrounding environment and may negatively impact groundwater or surface waters that serve as drinking, recreational, shellfish harvesting and irrigation water sources.

Unfortunately, there are many gaps in our knowledge regarding survival and fate of manure-borne pathogens originating from AFOs. This information gap, in part, is driving a multi-agency effort by the U.S. Department of Agriculture (USDA) and the U.S. Environmental Protection Agency (USEPA) to develop strategies for the reduction of pathogens in manure and manure management systems. This article provides a background on AFOs, including livestock waste and management strategies, manure-borne pathogens and transmission to water, methods for determining pathogen sources, and a brief overview of the USDA-USEPA Unified National Strategy for AFOs.

Manure & management strategies
The USEPA defines AFOs as agricultural enterprises where animals are kept and raised in confined settings.1 Along with animals, large amounts of their waste—an estimated 128 billion pounds generated annually in the United States—are also present within the boundaries of the livestock operations.1 Compounding this problem, the number of U.S. livestock has increased while the number of AFOs has decreased. This intensification of the livestock industry concentrates large amounts of manure within some geographic areas.

States with the highest concentrations of one or more types of manure (cattle, swine and fowl) include Iowa, Kansas, Nebraska, Missouri, California, Colorado, North Carolina, Ohio, Texas, Pennsylvania, New York, Wyoming and South Dakota.2 In Nebraska alone, about 26 million tons of manure are generated yearly from feedlot cattle (18.5 million tons/year), dairy cattle (0.2 million tons/year) and swine (7.6 million tons/year).3 To deal with large amounts of livestock waste, AFOs utilize manure management strategies including storage in piles or lagoons, treatment to decrease nutrient and pathogen concentrations (i.e., composting), or spreading manure onto—or injection into—the soil to serve as a nutrient source for crops.

Manure-borne pathogens
Bacterial, viral and protozoan pathogens are excreted in the feces of infected animals and may pose a human health threat if they’re transported to waters common for the previously mentioned human uses. Some pathogens associated with waterborne disease that may be present in livestock manure include pathogenic Escherichia coli (including the infamous E. Coli O157:H7), Campylobacter jejuni, Salmonella species, Cryptosporidium parvum and Giardia duodenalis. All of these microorganisms cause diarrhea in infected humans, but some can be fatal in immunocompromised individuals (particularly AIDS and chemotherapy patients, the elderly and children).

Properties that can affect survival and transmission of manure-borne pathogens to water include numbers of animals infected, proximity of AFO to source waters, concentration of pathogens excreted, infectious dose (number of pathogens required to produce disease), and individual pathogen traits that allow survival when exposed to environmental conditions. Some manure-borne pathogens, for example Giardia and Cryptosporidium, are excreted in very high concentrations by young animals, while adults can excrete low numbers for extended periods of time.

For large AFOs, where many animals and their waste are kept within a limited geographic location, the low excretion of pathogens by adult livestock may lead to considerable environmental contamination, including nearby watersheds. Distance from a watershed is also important in transmission of manure-borne pathogens. The ability to be transported to a distant water source may depend on runoff events that can occur seasonally or sporadically throughout the year. It may require more than one of these events to transport the pathogen to a water source. Die off, predation or adsorption to large particles that settle out before reaching the water source can impede pathogen transport. Depending on the infectious dose, numbers ranging from 1 million down to as little as a single infectious unit can cause disease if ingested. Thus, the transport and survival of even very low numbers of some manure-borne pathogens like Campylobacter, E. coli O157:H7 and Crypto-sporidium from an AFO to surface water or groundwater can endanger public and animal health.

Manure-borne pathogens may be able to survive transport simply due to their transport “package,” or transmission method. Association with feces can help protect these pathogens from sunlight inactivation, predation and competition from other microorganisms. Further, individual traits of each pathogen may enhance its survival. For example, studies involving Salmonella species indicate that it’s able to survive up to 12 weeks in slurry-applied soil.4 Long term survival of E. coli has been demonstrated in manure and treated slurry5 and multiplication in water and sediments has also been reported.6 Campylobacter can also survive in surface water and associated sediments.7 The environmentally resistant stages of Giardia (cysts) and Cryptosporidium (oocysts) are excreted in feces, allowing these pathogens to survive harsh conditions, including chlorination applied for drinking water disinfection.

Routes of transmission
Animal manure serves as a vector for the transmission of pathogens that cause enteric illness (diarrhea, vomiting, etc.). Previous studies demonstrated fecal bacterial contamination can occur in streams nearby dairy farms and cattle pastures surface runoff from grazed pastures, springs and wells within the hydrological catchment of pastures, and subsurface runoff from manure-applied fields. Studies also demonstrated rain events can flush manure-borne bacteria through well-structured soils and contaminate shallow groundwater.8 The high numbers of pathogens excreted in AFO livestock feces, combined with the belief that manure can protect pathogens from harsh environmental conditions, increase their potential to reach human water sources by one or more pathways.

Dumping or direct deposition of animal waste into water bodies is one route that pathogens can pollute surface water. AFOs that directly discharge animal waste into waterways, however, are issued permits (by the USEPA) that require the AFO to implement national effluent guidelines. Designated uses of the wastes, water quality criteria to protect these uses and an anti-degradation policy are included in these guidelines.

Polluted runoff is probably one of the most important sources of water pollution, according to the 1998 Clean Water Action Plan (CWAP).9 Rain or other events that produce runoff from fecally contaminated sites, such as manure applied on fields, animal pens and other manure management sites, may actively transport pathogens to groundwater and surface waters critical to a variety of human uses. Irrigation water contaminated with animal manure may increase pathogen transmission to susceptible individuals (animals and humans) if the irrigated crops are minimally processed before consumption. Another potential route is the natural (wind) transportation of pathogen-containing water droplets or dust particles from waste storage areas, animal pens or effluent application through sprinkler irrigation systems (see Redefining the Source…).

Eliminating information gaps
Under the 1998 CWAP, a unified national strategy was developed between the USDA and the USEPA.9 The “USDA-EPA Unified National Strategy for Animal Feeding Operations” is designed to minimize water quality and human health impacts caused by AFOs, while sustaining U.S. livestock production. Activities developed between the USDA and USEPA include coordinated research projects, technology transfer activities, technical innovation, compliance assistance and establishment of a single point information center.

Examples of research to be carried out by microbiologists working for the scientific research branch of the USDA, Agricultural Research Service (USDA-ARS), includes determination of:

  • Methodologies for rapid and specific detection of pathogens and their sources,
  • The types and seasonality of pathogens at AFOs,
  • Pathogen survival and fate within and outside AFOs,
  • Pathogen transport from AFOs to nearby watersheds or groundwater,
  • How animal diet affects pathogen excretion, and
  • The usefulness of indicator microorganisms as surrogates for pathogen detection.

This research and other coordinated efforts will enable the scientific evaluation of the impact that AFOs have on water quality and development of strategies to reduce or eliminate pathogens and other contaminants in water. These activities also will provide invaluable information to assist regulatory authorities in protecting water quality and public health. For more information on the USDA/EPA Unified Strategy, see http://cfpub.epa.gov/npdes/home.cfm? program_id=7

Conclusion
Animal feeding operations amass large concentrations of animal waste within a confined area. Animal waste that contains nutrient overloads and human pathogens can reach water by direct deposition, runoff events or wind. Still, evidence of the transport and fate of viable and manure-borne human pathogens is lacking in scientific literature. Recognizing potential human risks from manure-borne pathogens, the USDA and USEPA developed a “Unified National Strategy for Animal Feeding Operations.” This coordinated effort will enable the scientific evaluation of the impact that AFOs have on water quality and the development of strategies to reduce or eliminate pathogens and other contaminants in water.

References

  1. USEPA, “Why does EPA want to change the NPDES regulations and effluent guidelines for CAFOs?” EPA 833-F-00-016, USEPA Office of Water, Washington, D.C., 2001.
  2. USEPA, “Environmental Assessment of Proposed Revisions to the National Pollutant Discharge Elimination System Regulation and the Effluent Guidelines for Concentrated Animal Feeding Operations,” EPA-821-B-01-001, USEPA Office of Water, Washington, D.C., 2001.
  3. Sander, J., J. Powers and B. Eghball, “Nebraska Manure Resource,” Nebraska Cooperative Extension EC95-141-B, University of Nebraska, 1995.
  4. Taylor, R.J., and M.R. Burrows, “The survival of Escherichia coli and Salmonella dublin in slurry on pasture and the infectivity of S. dublin for grazing calves,” British Veterinary Journal, 127:536-542, 1971.
  5. Kudva, I., K. Blanch and C. Hovde, “Analysis of Escherichia coli O157:H7 survival in ovine or bovine manure and manure slurry,” Applied Environmental Microbiology, 64:3166-3174, 1998.
  6. Hancock, D.D., T.E. Besser and D.H. Rice, “Ecology of Escherichia coli O157:H7 in cattle and impact of management practices,” p. 85-91, J. B. Kaper (ed.), Escherichia coli O157:H7 and Other Shiga Toxin-Producing E. coli Strains, ASM Press, Washington, D.C., 1998.
  7. Jones, K., “Campylobacters in water, sewage and the environment,” Journal of Applied Microbiology, 90:68S-79S, 2001.
  8. McMurry, S.W., M.S. Coyne and E. Perfect, “Fecal coliform transport through intact soil blocks amended with poultry manure,” Journal of Environmental Quality, 27:86-92, 1998.
  9. USDA and USEPA, “Unified National Strategy for Animal Feeding Operations,” website: www.epa.gov/npdes/pubs/finafost.htm
  10. Ong, C., W. Moorehead, A. Ross et al., “Studies of Giardia spp. and Cryptosporidium spp. in two adjacent watersheds.” Applied and Environmental Microbiology, 62: 2798-2805, 1996.
  11. Slifko, T.R., H.V. Smith and J.B. Rose, “Emerging parasite zoonoses associated with water and food,” International Journal of Parasitology, 30:1379-1393, 2000.
  12. Fayer, R., U. Morgan and S.J. Upton, “Epidemiology of Cryptosporidium: transmission, detection and identification,” International Journal of Parasitology, 30:1305-1322, 2000.

About the author
Dr. Jeanette Thurston-Enriquez is a microbiologist with the USDA-ARS Soil and Water Conservation Research Unit and Adjunct Assistant Professor at the University of Nebraska.  Her current research projects include determining the occurrence and dissemination of manure-borne zoonotic pathogens from animal feeding operations, Cryptosporidium removal from river water during bank infiltration, and development of sensitive and rapid methods for the detection of environmentally transmitted pathogens. She can be reached at (402) 472-8935, (402) 472-0516 (fax) or email: jthursto@unlnotes.unl.edu

UV—Is the Water You’re Drinking Safe?

Saturday, July 20th, 2002

By Bruce Eccleston

Summary: With help of advanced research in the last few years, UV has elevated itself in the minds of water treatment dealers everywhere. The following article makes the case for the technology and what dealers and consumers alike might look for in an efficient system.


Is the water you’re drinking safe? Could your customers get ill if they drink the water in their homes? The proper treatment of your water supply is very important, and this shouldn’t only be for taste, color, smell or softness of their water, but also its microbiological safety.

A variety of microorganisms in the water supply can cause illness, especially for the young and elderly of our households who may have weaker immune systems. This is why disinfection of home water supplies is a very important part of the complete water treatment system. Do you or your family want to consume microbiologically unsafe water? Do your customers? Of course not. Safe drinking water and disinfection equipment can be important parts of the treatment system to provide customers with what they want. Safe drinking water is everyone’s wish. If they don’t have it at home, then they’ll buy it. Why do you think the bottled water industry has grown to a multi-billion dollar one so quickly?

In household applications, chemical treatment has been in use—whether by water utilities or well owners—for many years. With a chemical treatment process, you’re adding certain levels of a specific chemical, for example, chlorine. The water must be held in a holding or storage tank for a minimum amount of contact time to provide proper exposure time for the chemical to effectively disinfect the water. Chemicals can also add an unpleasant taste to water that’s unwanted by most individuals or home-owners. With chemical treatment, there’s also the possibility of forming by-products that can cause harmful long-term side effects. While chemical treatment for water disinfection may offer some protection, it also has many disadvantages over other processes for home water treatment .

Meanwhile, ultraviolet (UV) light has come to the forefront for disinfection applications replacing many chemical installations, or significantly reducing required chemical use. UV is a proven technology that can provide microbiologically safe water for the entire household. It’s been utilized for disinfecting water for a number of years. In fact, the federal policy statement regulating UV installations dates to 1966.1 UV treatment is what’s referred to as point-of-contact treatment. The water is disinfected as it passes by the UV lamp located in a vessel assembly.

UV dosage
The UV spectrum is located between visible light and X-rays. There are three levels of UV—UVA, UVB and UVC. The most effective wavelength for the disinfection process is in the UVC range at specifically 254 nanometers, or nm (see Table 1). UV dosage is a calculation of the total UVC intensity provided by a UV system at the rated flow. In basic terms, a UV dosage calculation is based on the amount of UVC output from the UV lamp, volume of water contained in the UV reaction chamber (or disinfection area) and retention time or flow rate. When all this information is formulated, it provides a UV system dosage calculation listed commonly as milliwatt seconds per square centimeter (mW-sec/cm2) or milliJoules per square centimeter (mJ/cm2), measurement representations that are equal to one another, i.e., 1 mW-sec/cm2 = 1 mJ/cm2.

Dosage calculations are referred to in two aspects—BOL (beginning of lamp life) and EOL (end of lamp life). BOL is the UV dosage that’s provided when the system is first installed or the UV lamp is replaced. Then there’s EOL, which is the most important calculation for a UV system. This is the system’s UVC dosage at the time of UV lamp replacement. Most UV manufacturers will rate their UV systems at an EOL UV dosage. This indicates the UV system will provide the stated minimum amount of UV dosage throughout the life of the UV lamp. If it’s unclear what the UV dosage level is on a specific brand/model, or if the dosage isn’t stated at EOL or BOL, ask your supplier or the manufacturer of the equipment to provide the UV dosage at EOL.

The UV lamp produces a radiation at 2,537 Angstrom units, or 254 nm wavelength, which is specific to the most effective wavelength for germicidal disinfection. The UV dosage is one of the most essential parts of knowing if the UV system you install will properly disinfect the water supply. Different microorganisms require different specific amounts of UV dosages to properly disinfect and provide the maximum log reduction of contaminants (see Table 2). A UV system that doesn’t provide enough UV dosage for the various possible microorganisms may not effectively disinfect the water supply.

The amount of UV dosage is very important to achieving the proper disinfection. UV dosage can typically range from 16 mJ/cm2 to 40 mJ/cm2 at 254 nm and EOL. The latest UV technology provides UV dosages at rated flow of 40 mJ/cm2 at 254 nm and EOL. The increased dosage in the system is to provide not only greater bacteria reduction but also to target various viruses and spores. Today’s advanced UV systems are designed to achieve the increased UV dosages at the rated flow and incorporate many features that provide end-users with a consumer-friendly water disinfection system. More of today’s UV systems also have ANSI/NSF Standard 55 Class A approval. One of the requirements for this certification is that UV dosages at rated flow be a minimum of 40 mJ/cm2 at 254 nm and EOL. This provides the public with assurance the system has been tested and approved by an independent third party laboratory and will work as stated by the manufacturer.

Pretreatment
Providing proper influent water quality to your UV system is very important. A UV system is very rarely a standalone treatment device. This is because transmissivity of the UV light through the water can be affected by constituents in raw water that can reduce its effectiveness through shadowing, scaling or fouling of the lamp or its quartz sleeve, discoloration of the lamp sleeve due to aging, and other effects (see Figure 1).

Monitoring the UV system
A feature provided on many of today’s advanced UV systems is monitoring of the UV lamp life. Many UV systems provide simple on/off visual and/or audible indicators of the UV lamp status. This is a good feature but doesn’t indicate if the UV lamp life has expired, only if the UV lamp is operational or not.

Today’s more sophisticated UV systems incorporate a very beneficial feature to provide a countdown of the UV lamp life remaining, which is typically rated at one year. This lamp life countdown begins at BOL and extends to EOL, as stated by the manufacturer. This ensures, when it’s time to change the UV lamp, the end-user is notified via an audible/visual alarm. Some systems even incorporate a snooze feature that allows end-users to silence the audible alarm for a given amount of time. If the UV lamp isn’t replaced in that time, they will be notified again. This notification allows them to make a scheduled appointment with the service/dealer to replace the UV lamp. Once this is done and the UV system is properly reset, it will once again begin the UV lamp life countdown.

Other features incorporated into many UV systems include monitoring of the UV intensity. This is monitored from the UV lamp through the water to the edge of the contact vessel. UV intensity is then displayed on the system. The display will be in various formats depending on system design and manufacturer. The UV monitoring feature provides important information on the status of the UV system and whether or not it’s providing an effective UV dosage for the system.

In selecting an effective UV system (see Figure 1), use of a normally closed solenoid valve should also be taken into consideration to make the unit as fail-safe as currently possible. Most UV systems provide a connection for this type of solenoid valve. Some connect into the system with a simple plug while others require electrical connections in the control panel or electrical enclosure. In either case, if such a valve is attached, the system will shut down both the valve and water flow under certain conditions. These conditions vary but typically include UV lamp failure, low UV intensity and EOL.

Conclusion
When selecting a water disinfection system, be sure to include UV as a choice. More often these days, it should be the preferred method. UV systems don’t add anything to the water and don’t create any harmful by-products that are possible with chemicals. UV systems come in many different dosage ranges, flow rates and features. Be sure you’ve reviewed all the systems available to end-users, so they can make an educated choice when selecting the UV system best suited for their homes.

Acknowledgment
The author would like to thank Jesse Rodriguez, sales and marketing vice president at WEDECO Ideal Horizons, and Brenda Dunlap, executive assistant at the company, for their assistance with this article.

References

  1. HEW, “Policy Statement on Use of the Ultraviolet Process for Disinfection of Water,” Department of Health, Education and Welfare (HEW), Public Health Service, Division of Environmental Engineering and Food Protection.
  2. Rodriguez, J., “An Introduction to UV Disinfection,” WC&P, August 1996.

About the author
Bruce Eccleston is the residential products sales manager for WEDECO Ideal Horizons, of Poultney, Vt. He has provided technical UV seminars for organizations such as the Water Quality Association, Eastern WQA and other organizations. Eccleston has over 10 years of UV technology experience including residential, commercial and industrial applications. He can be reached at (802) 287-4488, (802) 287-4486 (fax), email: beccleston@wedecouv.com or website: www.wedecouv.com

Water Stores Meet Needs of Consumers and Contractors Alike

Saturday, July 20th, 2002

By Sam Karge

In the water treatment industry, the concept of the water store has evolved in recent years. A full-service retail water store provides solutions to both consumers and business buyers for their water purity problems. While they’re not new to the industry, the number of water stores has increased steadily over the years as consumers have shown growing interest in the need for a continuous supply of high quality drinking water.

The need for water stores
Regardless of municipal water quality, many consumers choose to treat water in their homes to improve taste and provide extra protection against contaminants. While consumers want a better alternative to their existing tap water, they’re often unsure of the ways to improve household water.

“For years, consumers relied on the delivery of bottled water to their homes, since a retail setting did not exist or existed in limited capacity,” said Tom Commers, president, Commers Water of Blaine, Minn. “The water store offers consumers and contractors an easy way to purchase water treatment products firsthand, allowing them to see—and understand—the product before making a purchase.”

For consumers, the water store provides an outlet for education about water quality, and the available treatment technologies that will deliver the constant supply of pure water they desire. For contractors, they look to water stores to provide high quality components and equipment from a supplier they can trust.

These water stores have evolved beyond simple, storefront, fill-it-yourself stations that emerged in Sunbelt states in the early-’90s as an alternative to bottled water delivery and water vending machines. A few water store proprietors may have expanded their expertise to include in-home water treatment options from pour-through carafes to undersink filtration to whole house softening systems. Traditional water treatment equipment dealers, meanwhile, have expanded their own shops in the opposite direction to offer more simple water treatment solutions.

Like any other retail outlet, the water store allows consumers to browse through a variety of water treatment products at their leisure. They can ask questions, evaluate different technology options and even purchase bottled water directly from the store. For commercial or household customers looking for purification system components, they’ll find products such as carbon filters and home reverse osmosis (RO) systems and membrane elements that can be installed to treat tap water at the point-of-use or point-of-entry (POU/POE).

“Whether it’s bottled water or in-home purification systems, water stores combine the convenience of retail shopping with the advanced knowledge and high-end technology they require,” added Commers.

Consumer demand
A driving force behind the success of the water store is the consumers’ increased demand for information; more and more they insist on having all of their questions answered before they make a buying decision. They also want information from more than one source, rather than believing everything a salesperson tells them. For example, many consumers research items extensively online before taking a trip to the store to look at a product.

Along with this enhanced awareness comes an increased comfort level with traditional buying. Over the past few years, there has been a boom in the number of specialty stores targeted to specific consumer needs. This is making the water store an attractive option. Contractors, on the other hand, rely on the speed and convenience of water stores to stock products for resale and installation in homes and commercial buildings.

Either way, the goal of the water store is to match the correct product with the customer’s needs, while educating and explaining product benefits. Most water stores employ certified water specialists whose job is to educate customers about water quality concerns and how technology can be applied to remedy these problems. Better education of the end-user leads to continual growth of the industry. Consumers benefit from better water quality, and water stores benefit by staying on top of consumer preferences to help plan future product and service offerings.

Another trend inherent to today’s savvy consumers is a greater emphasis on healthy living, resulting in more careful and deliberate health-related choices. For example, the bottled water industry has seen a continued increase in sales as customers become more aware and concerned about health risks and the potential threats to their drinking water supply. With this increased interest, water stores have stepped in as a place for consumers to meet all of their water purification needs.

A win-win water solution
Cost savings is another benefit consumers gain by purchasing from a water store. While bottled water sold through grocery stores or large water retailers is convenient, many consumers want a continuous supply of pure water in their homes at an affordable price.

“Today, many homeowners have purchased—or specified from their building contractors—filtration and RO equipment instead of relying solely on bottled water,” commented Commers. “With a water store, consumers are able to get the products, service and convenience they need without the high cost associated with buying single-serving bottled water from a large general purpose retailer.”

Consider this—filling bottles with water at a water store costs about 30 cents per gallon, and in-home systems average around 10 cents per gallon. This compares to the $2-per-gallon cost of having bottled water delivered to a home or business. Whether consumers come in to refill bottles with pure water or purchase an in-home purification system, they save money.

In addition to cost savings, a visit to the water store is often more convenient than coordinating schedules to have water delivered. Even though bottles can be left outside if the consumer isn’t home, this isn’t always a viable option. In colder climates, for example, leaving bottled water outside can easily mean frozen water by the time a consumer gets home.

“In an effort to accommodate consumers, many water stores are opening outlets in high traffic areas to make themselves more accessible,” said Commers. “Now consumers can decide when they need to refill their bottles or replace a filter, and do so on their own time.”

This ultimately puts consumers in control. Visiting the store gives them the opportunity to understand the technology behind the product so they can more accurately determine what is best for their families.

Another edge the water store brings is the benefit of advanced technology in a retail setting. Many water store products now incorporate technology once used only in industrial applications. By working directly with water treatment system manufacturers, water stores are able to design systems that use innovative technology, receive detailed training on new products and ultimately gain industry expertise. In turn, the store gives manufacturers insight into consumer trends and important market data. In the end, the consumer gets high quality products and service designed to meet their specific pure water needs.

What’s next?
As consumer interest continues to drive water treatment industry growth, water stores are uniquely positioned to capitalize on this trend. Water stores are responding by offering a wider selection of water treatment products, as well as non-water related products. For example, with in-home purification systems in place, consumers are looking for special household cleaners—such as laundry detergents—that are designed to work specifically with conditioned water. In an attempt to better understand customer needs, many stores have placed more emphasis on education and marketing to draw consumers to the store. This allows them to grow their customer base while gaining insight about the consumer. By reacting to consumer needs and providing them with the necessary solutions, water stores can expand their potential product or market base.

Conclusion
Despite all of the sweeping changes in the industry, one thing is for sure—water stores have a place in the future direction of household water treatment. By catering to consumers’ water needs and looking ahead for potential changes in demand, a store can grow and succeed in times of economic uncertainty. As the market continues to evolve, the water treatment industry must be willing to change as well.

About the author
Sam Karge is a project manager for Osmonics’ Household Water Group in Milwaukee. He can be reached by email: skarge@osmonics.com

Filters Based on Bioactive Nanofibers

Saturday, July 20th, 2002

By Fred Tepper and Leonid Kaledin

Summary: A form of bioactive nano-alumina fibers attracts and retains virus and other macromolecules by electrostatic forces. These fibers have been incorporated into fibrous (“depth”) filters and were found to have up to a log 7-8 retention for virus even at flow rates several orders of magnitude greater than could be obtained using microporous membranes.


Asmall—about 2 nanometers (nm), or 0.002 microns (µm), in diameter—fiber with a high surface area of roughly 300-600 square meters per gram (m2/g) has been developed using boehmite (AlOOH) as the main component—and has exhibited some unusual filtration capabilities of the fibers.

The large number of hydroxyl (OH-) groups available on the nanofibers generates a positive charge in water solution such that it will attract and retain negatively charged particles including bacteria, virus, organic and inorganic colloids and negatively charged macromolecules. Data are presented on the adsorption capability of the fibers. Filter media has been prepared and tested for virus retention and results are presented. These data show high retention at high flow velocity—about 0.5-1 centimeters per second (cm/sec).

Processing & composition
Bioactive nanofibers are produced in kilogram quantities in three steps:

  • Sol-gel reaction
  • Filtration of sol from water
  • Heating to 200-400°C

The product is a white, free-flowing powder consisting of fibers, again, approximately 2 nm in diameter and tens to hundreds of nanometers long, collected in aggregates. X-ray diffraction shows the fibers are principally boehmite (AlOOH) with minor phases of gamma alumina and aluminum hydroxide, or Al(OH)3. The amount of Al(OH)3 decreases above 200°C as gamma alumina content increases. Beyond approximately 400°C, the principal phase is gamma alumina. The fiber shape is maintained to about 1,050°C, where the principal phase becomes alpha alumina. Figure 1 shows the surface area as a function of heat treatment. A peak in surface area is seen at around 250°C.

Dynamic testing
Our first virus test data are seen in Table 1. The test involved passing 60 milliliters (ml) of water containing 105 plaque-forming units per milliliter (PFU/ml) of virus in buffered pH 7.5 water through 25 millimeter (mm) diameter controls (using Millipore HA 0.4 mm membrane) at a flow rate of 112 ml/minute (min). We then challenged a thin bed (0.7 grams, gm) of the nanofibers that had been spread over the control with the same virus mixture. With a single filter there was sufficient scatter indicating bypass of the sorbent, so further testing was done with a pair of filters. The virus was detected as plaque-forming units using a double-layer assay with E. coli as the host. The results (see Table 1) show very high efficiency for virus retention by the nanofiber vs. the control.

Static ‘capacity’ testing
Experiments were done to determine the degree of attachment of different virus to the bioactive nanofiber. The primary purpose was to determine which of the different process variants best adsorbed virus. Bacteriophages MS-2 and PRD-1 were diluted in 150 ml of 0.02 molar imidazole/0.02M glycine buffer (pH 7.2) to give an effective concentration of approximately 8×105 PFU/ml. The nanofibers (0.5 gm) were placed into a 15-ml conical centrifuge tube containing 10 ml of the bacteriophage solution. The powder was completely dispersed by vortex mixing and was shaken on a rocking table for 15 minutes. The mixture was centrifuged at low speed (2,500 rpm) to collect the powder at the bottom of the tube and the supernatant—the usually clear liquid overlying material deposited by settling, precipitation or centrifugation—was assayed for the presence of virus. An initial and final aliquot (fraction) was taken from the buffer solution containing bacteriophage to verify that virus concentration remained constant throughout the time of the experiment. Table 2 shows that heating to 450°C had no noticeable effect on the attachment of either virus. The data also demonstrate that the fibers will clear virus from solutions to greater than log 2 in one cycle. Experiments are ongoing with respect to determining the static capacity of virus on the nanofiber.

We then prepared fibrous filter media containing modified nanofibers in conjunction with supporting fibers such as cellulose/glass fiber mixes. The tests (see Table 3) involved a solution at pH 7.5 containing approximately 107 PFU/ml virus at a flow of approximately 1 ml/sec through a 2.5-cm diameter filter. The (duplicate) data show that there is greater than 6 log (99.9999 percent) retention starting at approximately 20 weight percent (wt-%) bioactive nanofiber. It’s likely there’s increasing retention capability with loadings greater than 20 wt-%, but the virus assay technique is currently limiting. More recent data show about 8 log retention.

Testing with simulated salt water shows no reduction of virus retention, suggesting such filters may be used as a pre-filter for reverse osmosis (RO) membranes. Virus retention was also not affected when raw sewage was substituted for water in preparing the virus challenge solution.

Filtration mechanisms
The two basic mechanisms for filtration pathogens from water are via sieving and electrokinetic adhesion (adsorption, absorption, etc.). Ultrafilters and RO membranes are generally polymeric and screen particles using pores smaller than the particle. The particles accumulate on the surface rather than in the depth of the filter. The capacity of such filters suffers because they easily clog at the surface. Also, any defect in a surface pore could result in lowering of pressure drop and allow by-pass, compromising the filter.

Depth filters use fibers to create a random array of irregularly shaped pores generally larger than the particle. Thin layers of such filter media are ineffective in filtering small particles. By thickening the filter (many “unit” layers), however, a subsequent layer coincides with the larger pore of the previous layer so the average pore size declined as the depth filter is thickened. For most efficient capture, the particle and fiber diameter (and resultant surface area) should be of similar size. Depth filters generally are capable of removing approximately 85-95 percent of particles, but their use for complete sterilization (e.g., greater than 4-log removal) for virus hasn’t been achieved nor anticipated. Structurally, filters produced from the nanofibers are typical of depth filters. Their fiber diameter is much smaller than previously available fibers, though, so there’s far greater opportunity for interception and capture of small particles.

Streaming potential, which is generated in dilute solutions moving at high velocity through a filter, is useful in determining the filter’s electrostatic properties. Such measurements showed that our fibers are highly positive even in neutral water. The high density of positive charge is the result of the large population of hydroxyl groups on the surface, which are readily distributed across the fiber. Thus, capture is enhanced if the particles are negatively charged. Bacteria and their fragments exhibit negative charge due to their cell wall chemistry, and virus are also negatively charged so they are attracted to and adsorbed by the nano-alumina fibers.

Flow velocity data
One of the concerns with using fibers as small as 2 nm is the expected high pressure drop, particularly during high loading in the depth filter. A series of bioactive nanofiber filters similar to those shown in Table 3 were tested for flow properties at a pressure of 0.2 atmospheres (0.2 bar). Table 4 shows that increasing the loading of nanofibers causes an increase in pressure drop. Nevertheless, the attainable flow rates are substantially greater by about two orders of magnitude as compared to equivalent ultraporous membranes. For instance, Millipore VM (50-nm rating) and VS (25-nm rating) flow velocities are respectively 0.01 and 0.0025 cm/sec at a pressure differential of 0.7 bar. Note that the data were developed at lower 0.2-bar for pressure, so that the flow performance of filters is even more favorable. Part of the reason for the high flow capability of the nanofibers is that it’s hydrophilic, while membranes composed of cellulose esters, plastics and PTFE are generally hydrophobic—water repelling. Water can be forced through hydrophobic filters, but the pressure drop required to force it through pores smaller than 1 µm becomes prohibitively high, and the risk of uneven wetting increases. Thus, flow rates of membrane filters suitable for virus retention are generally in the range of 300-600 liters per square meter per hour (L/m2/hr). Nanofiber filters range between 10,000-20,000 L/m2/hr.

We’re currently studying retention of 30-nm latex spheres and obtaining breakthrough capacity data. These mirror results we’ve gotten with virus. These results also show substantial retention without excessive pressure drop at least to the break point of the filter. Testing is under way with E. coli and 3-µm size latex spheres.

Conclusion
The features and benefits of bioactive nanofibers can be summarized as follows:

  • High (about 7 log) virus clearance—Can be increased by thickening filter.
  • Higher flow rate—Several orders of magnitude greater than equivalent membrane filters.
  • Higher capacity for particulates.
  • Higher resistance to clogging.
  • Robust—Point defects in a depth filter are compensated by fibers randomly spaced behind such defects, while there’s no such redundancy in a membrane filter.

Suggested applications include:

  • Purification of water for residential, medical, dental and military purposes;
  • Filter sanitization of medical serums and biological fluids;
  • Filter sanitization of other pharmaceutical products;
  • Separation of macromolecules such as proteins, DNA, etc., on the basis of charge characteristics of the particles;
  • Concentration for the purpose of bio analysis;
  • Tissue engineering—Compacts of nanofiber have been shown1 to attract and retain osteoblast (bone) cells and allow their proliferation at higher rates than hydroxyapatite; or
  • As a substrate for biosynthesis.

Acknowledgment
The authors would like to thank the U.S. Department of Energy and NASA for their support in the development of these filters.

References

  1. Gutwein, L.G., F. Tepper and T.J. Webster, “Increased Osteoblast Function on Nanofibered Alumina,” Proceedings of the 26th International Conference on Advanced Ceramics and Composites, Cocoa Beach, Fla., Jan. 13-18, 2002.

About the authors
Fred Tepper and Dr. Leonid Kaledin are with Argonide Corp., of Sanford, Fla. Argonide is a manufacturer of nano-powders and Nano Ceram™ nano-alumina fibers. Introductory sales of NanoCeram filters are planned for this fall. They can be reached at (407) 322-2500, email: fred@argonide.com or website: www.argonide.com

10 Things You Should Know about Pool Chemistry and Water Testing

Saturday, July 20th, 2002

By Joe Sweazy and Drew Chuppe

Summer is the pool and spa season, so here are a few tips for you on pool and spa water chemistry:

1. Algae bloom? Check nitrate.
If an algae bloom occurs in a pool, check the nitrate level. Nitrates can get into a pool from a variety of sources, including fertilizer overspray, bird droppings, rain and well water. Unfortunately, algae love nitrates; if the nitrate level is too high, you may encounter algae blooms even though the water appears to be perfectly balanced. Keep the nitrate level below 10 parts per million (ppm); if your test strip reads above that level, you should partially drain and refill the pool.

2. Maintain a chlorine residual
Even if you’re using an ozonator or a mineral purification system, you still need to maintain a residual chlorine level. Most of the ozone in a pool will dissipate within 30 minutes. After the ozone becomes depleted, you need some residual chlorine to protect the water from any additional contaminants that may be introduced. Similarly, chlorine supplements a mineral system by oxidizing contaminants and preventing algae growth. You should maintain a minimum of 0.5 ppm free chlorine in pool water if using one of these alternate sanitizing systems.

3. Watch cyanuric acid level
Keep the cyanuric acid level in the right range to avoid chlorine loss. In outdoor pools, the sun’s ultraviolet (UV) radiation quickly breaks down chlorine. Cyanuric acid stabilizes the chlorine against effects of sunlight, acting like sunscreen for the pool. But too much cyanuric acid can reduce chlorine efficiency. It also will elevate the total dissolved solids (TDS) level, which may cause scale formation, stains or cloudy water. Use test strips frequently to keep the cyanuric acid level in the ideal range of 30-50 ppm.

4. Balance and hot tub TDS
If the water is balanced in a hot tub but you’re still having trouble, test the total dissolved solids (TDS) level. The TDS increases every time you add chemicals to the water. In hot tubs, where jets and high temperatures speed up evaporation, the TDS level builds up more rapidly. Elevated TDS can promote bacteria growth or corrosion, even when the water seems to be properly balanced. To avoid these and other problems, use a conductivity meter or TDS test strip regularly.

5. Test total, not free, bromine
In a brominated hot tub or pool, be sure you test for total bromine, not free bromine. Total bromine includes free and combined bromine (also called bromamines). Unlike chlorine, both the free and combined forms of bromine are effective sanitizers, so you need to measure them both. One word of caution—some test products measure both free chlorine and bromine. This type of test only measures free bromine, and will not give the most accurate picture of the sanitizer remaining in the water.

6. Know your sanitizer pH
Learn the pH of various sanitizers; they can help you balance the pH in the pool. For example, if you normally treat a pool with trichlor tablets (very acidic, with a pH of 2.8), then use sodium hypochlorite (pH of 13) when you shock the water. They will offset one another, helping to keep your pH in the ideal range of 7.2-7.6.

7. Know your limitations
Know the uses and limitations of your testing method. If using an OTO test kit, keep in mind that it only tests for total chlorine, whereas free chlorine is the effective sanitizer in a pool. DPD kits measure free chlorine; however, they’ll yield false positive readings for free chlorine in the presence of very high combined chlorine (chloramines) levels. This is a frequent problem when opening pools in the springtime. Finally, all liquid reagents and test strips will expire. For accurate results, use a test product with a clearly marked expiration date, and don’t use the kit or test strips beyond that date.

8. It’s OK to be shallow
You don’t have to dip your test strip 18 inches below the surface to get accurate test results. With any circulation at all, the chemical levels at the surface will be nearly identical to the levels at the bottom of the pool. The difference between 2 inches and 18 inches below the surface would be even less significant. Therefore, testing at fingertip depth is all that’s required.

9. Spring is more demanding
Chlorine demand is often significantly higher in the spring when opening pools. When a pool is closed, microorganisms that aren’t destroyed by chlorine, or some other sanitizer, will grow and multiply in the water. This is common when a pool is opened for the first time and there’s no free chlorine present. Under these conditions, you may need to add as much as 200 ppm of chlorine to re-establish a free chlorine residual.

10. Follow the directions
Whatever type of testing product you use be sure to follow the manufac-turer’s directions. Most inaccurate test results occur when individuals don’t follow directions—or follow the wrong directions. Not all manufacturers’ test strips are the same; updated versions of products may also use different test procedures. Therefore, you should never assume that the directions on one container are going to apply to another container’s strips.

About the authors
Joe Sweazy is a technical service associate for Environmental Test Systems, manufacturer of water quality and pool and spa test strips, based in Elkhart, Ind. He has published more than a dozen articles on pool and spa water chemistry and has presented numerous seminars at conferences of the National Spa and Pool Institute. Sweazy earned a bachelor’s degree in chemistry from Bethel College in Mishawaka, Ind., and is a Certified Pool and Spa Operator (CPO). He can be reached at (800) 548-4381, ext. 179, or email: jsweazy@hach.com

Drew Chuppe is the senior marketing manger for AquaChek™ Pool & Spa Test Strips at Environmental Test Systems. He and Joe Sweazy are co-authors of the AquaChek™ Dealer Training Program—a free, Internet-based training course on pool and spa water chemistry at www.aquachek.com/training. Chuppe can be contacted by email: dchuppe@hach.com

©2020 EIJ Company LLC, All Rights Reserved | tucson website design by Arizona Computer Guru