Water Conditioning & Purification Magazine

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Friday, April 19th, 2002

Beckman takes R&D reigns
Professional Water Technologies, of Vista, Calif., has hired James Beckman to lead the company’s ongoing research and development efforts and technical services department. Beckman has specialized in membrane process design and RO technical support since 1968 when he started working for the ROGA division of General Atomics, which evolved to become Fluid Systems and then Koch Membrane Systems. Professional Water Technologies develops, manufactures and sells an exclusive line of powder and super-concentrated liquid RO pretreatment and membrane maintenance chemicals.

Hartung joins group as VP
Severn Trent Services, of Fort Washington, Pa., announced that Robert Hartung, P.E., has joined the company as vice president of Water Operations for the Pipeline Services group. He will be responsible for the management of potable water field testing and engineering services. Previously, Hartung was employed for 25 years by BetzDearborn, a specialty chemical and service company managing water and wastewater systems that was recently purchased by General Electric, where he was manager of the company’s North American product line. Hartung graduated from Bucknell University with a bachelor’s degree in chemical engineering. The Pipeline Services group provides water distribution system evaluations including water audits, “C” factor testing, hydraulic modeling, leak detection, hydraulic grade line analysis and flow monitoring.

ASTM appoints vice chairman
Ken Schaeffer, president of Huntington Beach, Calif.-based Carbon Resources LLC, has been named vice chairman of the ASTM (American Society for Testing Methods) committee D-28 on activated carbon. The ASTM D-28 committee writes, reviews and issues all ASTM standards regarding activated carbon media testing and specification. ASTM standards are used worldwide for activated carbon manufacturing quality control and used carbon comparison testing.

Pentair gets new salesmen
Bill Couturier has been hired by Pentair Water Treatment as residential/commercial sales manager for the southeast U.S. region. He will represent Pentair Fleck and Structural tank products to the water treatment industry. Previously, Couturier held sales management positions with Barnstead Co, of Boston, as well as owned a residential water dealership in Maryland. He has also worked with GE’s Smartwater Division. In other company news, Marcos Apodaca was appointed sales manager for Mexico representing Pentair Fleck and Structural tank products to the water treatment industry. Apodaca has been in residential and commercial water treatment for the past eight years with experience in the sales and manufacturing of pumps, pre-charged tanks, filters and their installations.

Greenback to receive award
Dr. Mick Greenback, of Pittsburgh-based Calgon Carbon Corp., will receive the International Activated Carbon Conference Hall of Fame award on Sept. 27 in Pittsburgh. At the meeting, he will provide a lecture entitled, “New Detective Tools for the Activated Carbon Industry.” Previous award recipients include Dr. Milton Manes, George Tobias, Jonathan Cooper, Dr. Amos Turk, Dr. Gordon Culp and Dr. Mietek Jaroniec.

Global changes take place
Global Water Technologies Inc., of Golden, Colo., has announced the appointments of Steven Rash as president of Global Water Technologies Inc., Chad Moller as director of finance and accounting for GWT, and Ron Bernard as senior vice president of Applied Water Technologies Inc. Rash holds a bachelor’s degree in business administration from the University of Delaware, and a master’s degree in business administration from Southern Illinois University. Moller holds a bachelor’s degree in accounting and business administration from Dakota Wesleyan University. Bernard has a bachelor’s degree in chemical engineering from the New Jersey Institute of Technology. Global Water Technologies is a water technology and services company with major installations in the areas of power, process and HVAC.

Wittliff becomes new COO
Dan Wittliff has been appointed vice president and chief operating officer of Hydroprocessing LLC, an Austin, Texas-based technology company that has developed technology for the conversion of industrial or municipal organic sludges into useful products or power. Wittliff graduated from Southern Methodist University with a bachelor’s degree in mechanical engineering and his master’s degree in business administration is from the University of Oklahoma.

Texas water pioneer dies at 80; helped form TWQA in mid-1970s
Gilbert Warren Boerner, of San Antonio, passed away Feb. 19. He was 80. At the end of World War II, he went to Tufts University and earned a degree in economics. He attended the Wharton School of Business before beginning a career in the water quality improvement industry. “Gib” started in the Culligan system in Wheaton, Ill., in 1947 by working for his father-in-law, Wilbur L. Walton, who collaborated with Emmet J. Culligan and opened the first fledgling Culligan dealership (before they were known as Culligan)—W. L. Walton & Company, located in the Chicago area. Gib received top awards from Culligan International, including being named a top dealer in the United States and winning the “Culligan Silver Circle” and “Circle of Excellence” awards for all-around excellence. In 1987, the WQA honored him with the Hall of Fame Award and recognized him for his outstanding achievements in his personal and business life. Gib was instrumental in the formation of the Texas Water Quality Association in the mid-1970s along with other water conditioning pioneers including Sonny Cammack (who passed away last year) and the late Dick Grace, Jo Grace’s husband. Gib’s son, Bob Boerner, is president of Culligan Southwest. In lieu of flowers, memorial contributions may be made to the Oblate School of Theology, 285 Oblate Drive, San Antonio, TX 78216.

Ask the Expert

Friday, April 19th, 2002

Iron in my water

Question: What is the best method for removing iron from my well water? Thanks!

Sherry Stanley
Owls Head, Maine

Answer: Oftentimes, iron may appear in a soluble (dissolved) or insoluble (precipitated) state in your water. To significantly reduce the iron, you may need to chlorinate—or otherwise oxidize—the iron such that it comes out of solution and is more easily filterable. An oxidizing iron filter is very effective and a local dealer can recommend that for you. If the iron levels in your water aren’t too high, a softener will be very effective at removing iron as well. Some suggest that you shouldn’t rely on a softener as it tends to foul the ion exchange resins used to reduce unwanted constituents from your water, but others have experienced effective removal without negative side effects on waters with more than 25 ppm of iron using softeners.

If you’re looking at a water quality analysis, soluble iron—also referred to as “clear water” iron—will be represented as Fe+2 (ferrous). Insoluble iron—also referred to as “red water” iron—will be represented as Fe+3 (ferric). Because iron can combine with other elements, it also can be present in an organic complex, which can appear as colorless, yellow or brown. A more daunting problem is when iron bacteria may also be present, which can create reddish brown or yellow slime, clog plumbing and cause a nasty odor that’s fishy or oily. A rotten egg odor is generally associated with hydrogen sulfide (H2S), which can be associated with sulfate-reducing bacterias (SRBs) and is a whole other issue (see www.dnr.state.wi. us/org/water/dwg/sulferb.pdf).

For more information, see the following pages from the Wisconsin Department of Natural Resources website regarding iron and iron bacteria in drinking water:

You can also search www. wcponline.com archives by entering “iron” in the FIND box. While not every article will appear, only select ones are included online, you can ask that a copy of any article appearing in WC&P be sent to you through a simple email request that includes your address and/or fax number. No more than two articles per request, please, or there will be a small fee.

P.S. John Beauchamp’s articles “Ironing It Out (Part 1 and Part 2)” from July and August 1997 were perhaps the most comprehensive in WC&P on this subject in recent years. In discussing this item, he mentioned that he has seen iron significantly reduced with a softener up to 35 ppm and has heard of removal up to 150 ppm without negative consequences to the unit. Such performance, he admits, may be limited by water quality, particularly pH and oxygen levels. Unfortunately, our online archive only goes back through 1998. If you’d like copies of these articles, send your address or fax number and we’ll be happy to send them to you.

‘Cross into the Blue’ on the cutting edge

Question: I’m writing an article for a local Air Base (Mountain Home AFB) newspaper on water issues and was hoping you might be able to point me towards some good cutting edge information, statistics, etc. I’m floundering around the web and so far your site has been the most informative, and you appear to be the local expert!!! Thanks for your help.

Rod Russell
Boise, Idaho

Answer: Not sure what specific kind of stats you’re looking for, but there are all kinds of suggestions we could make with a more detailed request. A few market research companies may be able to help you, such as Frost & Sullivan or The McIlvaine Company, which specialize in the water treatment industry, although they may take more of a “big” water or industrial approach. Their reports generally cost a bundle, but you can find useful info in the report summaries/press releases on their websites. The Water Quality Association and International Bottled Water Association both do surveys of their industry that could prove helpful. Other than that, government websites are the best: U.S. Environmental Protection Agency (www.epa.gov/watrhome or www.epa.gov/safewater), U.S. Geological Survey (water.usgs.gov), Centers for Disease Control & Prevention (www.cdc.gov/ncidod/diseases/list_waterborne.htm). Another resource is the National Drinking Water Clearinghouse hosted by the University of West Virginia (http://www.nesc.wvu. edu/ndwc/ndwc_index. htm).

Global Spotlight

Friday, April 19th, 2002

CUNO Inc. reported record first quarter results for the period ending Jan. 31, 2002. Worldwide sales were $58.6 million, which remained relatively flat vs. the same period last year. Net income for the first quarter increased by 18 percent to $4.5 million from $3.8 million reported last year. 💧

Hall’s Culligan Water, of Wichita, Kan., has moved to its new location. The address is 10821 E. 26th Street North and the zip code is 67226. The phone number is (316) 267-5287 and the fax number is (316) 267-3502. 💧

Ozolutions Inc., a Toronto-based international marketer of water treatment systems, has announced establishment of a U.S. office in New York City. 💧

Household products maker Clorox Co. said quarterly net income fell 20 percent. The maker of Clorox bleach, Glad bags and Brita water filters posted net income of $51 million in the fiscal second quarter ending Dec. 31. That compares with $64 million a year ago. Sales rose 3 percent to $876 million. 💧

Advanced UV Inc., of Torrance, Calif., offers a free data sheet entitled, “A Matter of Taste: Ultraviolet Technology for Food, Beverage and Dairy Applications.” Advanced UV is a manufacturer of ultraviolet water treatment equipment. 💧

Waterlink Inc., of Columbus, Ohio, announced results for the first quarter of its 2002 fiscal year. Net sales increased 9.4 percent and were $18.4 million vs. $16.8 million in the prior year’s first quarter. 💧

Evaporator and biological wastewater treatment systems from USFilter have begun operation to treat pharmaceutical wastewaters for Albany, Ore.-based Synthetech Inc. Its contract with USFilter is worth $900,000. 💧

Noveon Inc., of Cleveland, has investigated the effects of water impurities such as flocculating/coagulating agents, natural organic compounds and biocides. The findings were published in “The Influence of Water System Impurities on the Performance of Deposit Control Polymers as Particulate Dispersants.” 💧

Golden, Colo.-based Global Water Technologies Inc., a full-service cooling water treatment company providing process cooling water, has enlisted Raymond James and Associates Inc. to provide analysis, valuation, structuring and financing of the company’s prospective acquisitions. 💧

The new principal owner of Australian Water Products, of Wagga Wagga, is Brian Hewitt following Thomas Goodman’s retirement. 💧

The Key Water & Air International Inc., of Lindsay, Neb., will provide custom-designed, automated ozone/bromine pool systems for two 270,000 gallon pools at Lincoln (Neb.) High School and a 85,000 gallon pool at the YMCA. 💧

Decanter Machine Inc., of Johnson City, Tenn., has acquired Diversified Machine Products LLC, of Roebuck, S.C. Decanter Machine is a manufacturer of industrial centrifuges for the wastewater treatment industry. 💧

Home Depot Inc. has turned to Professional Laboratories Inc., of Weston, Fla., a manufacturer of home safety test kits, to help meet consumer demand. The PRO-LAB™ brand Mold, Radon Gas and Water Quality Test Kits are now available at all 1,303 stores nationwide. 💧


NSF closes one lab, creates new mark, and works with Osmonics
NSF International said it would relocate its Sacramento, Calif., water products testing facilities to its world headquarters in Ann Arbor, Mich., to improve customer service. The relocation will mean closing the Sacramento laboratory, where much of the testing of drinking water treatment units (DWTU) had been performed. Currently, all products tested in Sacramento also require some additional testing in Ann Arbor to complete approvals needed for these products to display the NSF mark. All testing will now be performed at one location. The official closing of the Sacramento laboratories was scheduled for March 22. Employees impacted by the change are being provided severance packages, including career transition assistance and opportunities to fill open positions in Ann Arbor. Meanwhile, NSF has refocused its operations to correspond directly with the two major markets it serves—food and water. The reorganization allows NSF to meet more needs of customers in the two industries. NSF is combining its services—including product testing and certification, food safety audits, laboratory and toxicology consulting, education and regulatory—into two comprehensive food and water departments. Mark Jost, NSF’s senior vice president for Water Systems, is responsible for all services for the water sector. These include the Water Distribution Systems Program, the DWTU program, the USEPA Environmental Technology Verification Program and Environmental Research Services.

In other news, NSF has introduced a new mark for manufacturers to place on their certified products. The new mark includes the circular NSF logo with the words “independently certified” and the NSF website (www.nsf.org). Manufacturers of NSF-certified consumer products such as dietary supplements, DWTUs, bottled water and residential equipment may voluntarily adopt the new consumer mark for their certified products. The “independently certified” designation lets consumers know that the manufacturer has voluntarily sought independent, third party certification of the product. Finally, NSF and Osmonics Inc., of Minnetonka, Minn., have been working together to provide a data transfer program for clients wanting to use authorized Osmonics reverse osmosis membranes within their system. Osmonics has completed all required testing at NSF to allow for a data transfer under ANSI/NSF Standard 58 and is available for use under the NSF data transfer testing protocol. The requirements include performing a Standard 58 TDS reduction test of the manufacturer’s system with the Osmonics element in it. Calculations using test results determine if the system meets the performance requirements of the data transfer procedure.

Also, in late February, NSF received a letter from the California Department of Health Services outlining their policy on website marketing of water treatment devices. In short, the department considers websites to be national marketing brochures. As a result, they must comply with the requirements of the California Device Certification Program. Simply put, if a residential water treatment device is marketed on a website on the basis of health claims and is certified in California, the claims must be consistent with its California certification. Joe Harrison, WQA’s technical director, said the ruling should have little impact on the majority of dealers. “It’s the same law and same rules,” he said. “Before you snap to a judgment, I think you have to put yourself in California’s shoes.” Harrison added that many dealers not doing business in California would be wise to include a “Not for sale in California” disclaimer on their websites. The department will routinely check manufacturers’ websites during any application process as well as other general Internet searches for residential water filter sales. Section 116840 of the California Health and Safety Code provides for the assessment of civil penalties up to $5,000 for each violation.


PCI-WEDECO lands N.J. deal
PCI-WEDECO Environmental Technologies, of West Caldwell, N.J., was selected in late February to supply an integrated ozone generation system for the Little Falls Water Treatment Plant in Totowa, N.J. The company will provide an advanced treatment technology as part of an improvement to an existing drinking water treatment plant, which will produce almost 88 million gallons per day of drinking water. Black & Veatch, of Kansas City, Mo., and Killam Associates, of Millburn, N.J., designed the new ozone system as part of a major plant upgrade.

Flouride receives mixed bag
About two-thirds (65.8 percent) of the U.S. population received fluoridated water from public water systems in 2000, up from 62 percent in the early 1990s. This, however, still falls short of federal objectives for water fluoridation, according to a report from the Centers for Disease Control and Prevention. Currently, 26 states and the District of Columbia met the goal of 75 percent of the population receiving fluoridated water. From 1992-2000, five additional states—Delaware, Maine, Missouri, Nebraska and Virginia—achieved the 75 percent objective, and Oklahoma fell just short of the objective. Overall, the percentage of the U.S. population receiving fluoridated water increased from 62 to 66 percent, an increase from 144 million to 162 million people. Several states, including California and New Jersey, didn’t meet the objective, researchers noted in the Feb. 22 issue of CDC’s Morbidity and Mortality Report. Meanwhile, the American Dental Association (ADA) reports that current water fluoride levels are damaging some children’s teeth, according to the group’s February journal and echoed by a New York-based anti-fluoridation group.  

John Guest races at Daytona
Racing in the 24-hour Daytona 500 proved to be a monumental challenge for Mike Jordan and his team as he drove the John Guest-sponsored Porsche 911 GT3R at Daytona Beach, Fla. in February. A whole host of setbacks—two broken drive shafts, problems with the clutch, brake and radiator, and four tire punctures—put heavy demands on the pit crew. During the race, the car completed 503 laps while covering almost 1,800 miles. At one stage in the race, the car was in fourth place; it finished 18th in the GT class. “Teamwork is what a 24-hour race is all about,” said Jordan. “With all the misfortunes, the fact that we finished the race at all is a minor miracle. To have the success we did is a fantastic achievement. The team proved itself at every level—pace, grit, determination and discipline.”

Osmonics launches new line; reports strong results for 2001
Minnetonka, Minn.-based Osmonics Inc. has established a Specialty Separations Equipment product line. The product line is geared toward smaller-scale industrial plants and even small garage shops, enabling them to economically enjoy the same fluid recycling benefits available to larger operations. Products in the line will help industrial manufacturers minimize chemical usage, reduce waste and improve their productivity. The line will consist of packaged fluid treatment systems, using new and existing technologies that enable companies to treat small and medium capacity flows in their processes. Gerald Gach, a 20-year veteran, will head sales, marketing and development for the product line. Meanwhile, Osmonics reported sales of $207.4 million for the year ending Dec. 31, an increase of 3.6 percent vs. sales of $200.1 million for the prior year. All three of the company’s business segments reported sales increases in the fourth quarter compared to the same period in 2000. The Process Water Group showed a 10.5 percent increase and an 8.1 percent increase was achieved in the Household Water Group. The Filtration and Separations Group reported a 2.8 percent increase. In other news, the company now offers online shopping at www.shop.osmonics.com. Prior customer transactions could only be done via phone or fax.

Crane picks up Kavey Water
Crane Environmental, a Crane  company, has acquired Palmetto, Fla.-based Kavey Water. Kavey Water’s strengths in pre-treatment equipment for water purification complement Crane Environmental’s manufacturing of small to large reverse osmosis systems. “The synergies between the two companies are very significant,” said John Marrinucci, president and CEO of Crane Environmental. “This new relationship is beneficial to both companies by bringing two pieces of the water treatment process together to provide more complete water purification solutions for both companies’ customers.” Kavey Water will continue to operate as before. Customers with questions or concerns should contact Bill Kavey or Frank Van Horn at (800) 373-5454. With locations in Trooper, Pa., and Venice, Fla., Crane Environmental employs approximately 120 people and designs, manufactures and installs specialized water purification systems.

WQA to feature new section
A new section, bottled water, was introduced at the WQA Annual Convention and Exhibition in New Orleans, according to WQA Newsfax. This section will allow WQA members, who are interested in adding a bottled water component to their business, a chance to network with other members doing the same. Bottled water is the fastest growing category of beverage sales in the United States; case sales more than doubled between 1998 and 2000. “We would want to work with IBWA and use their resources for their expertise and contacts,” said Joe Harrison, WQA’s technical director. “Many of our member companies are getting into bottled water. They would like to get some information on bottled water issues such as labeling, regulations and other matters.” For more information, WQA members were invited to attend an educational session at the convention. In addition, the Bottled Water section’s first meeting was included as part of the Retailer/Dealer Section meeting. There’s been speculation that the WQA and IBWA may embark on a trade show together. Harrison said, “If we were to bring in bottled water, it would be an addition to what we are currently doing at the annual WQA show rather than a subtraction. It might be a longer show with different pavilions. It could happen as soon as next year if people decide they want to do it.” And what has been the reaction of WQA’s members? He replied, “The feedback has been all positive.” He added that the WQA has been in close communication with IBWA director Joe Doss on the topic.

USEPA passes microbial rule
The USEPA finalized the Long Term 1 Enhanced Surface Water Treatment Rule on Jan. 14. The purpose of the rule is to improve control of microbial pathogens, specifically the protozoan Cryptosporidium in drinking water, and address risk trade-offs with disinfection by-products. In short, the rule will force certain public water systems to meet strengthened filtration requirements. It will also require systems to calculate levels of microbial inactivation to ensure that microbial protection isn’t jeopardized if systems make changes to comply with Stage 1 Disinfectants and Disinfection By-products Rule.

Dentist equipment unclean? Report finds high bacteria
According to an August 2001 report by ABC’s 20/20, high levels of bacteria may frequently be found in dental equipment. Almost 90 percent of the water samples tested in 20/20’s investigation did not meet federal drinking water standards, and two-thirds contained oral bacteria from the saliva of previous patients. Part of the problem can be traced to stagnation. When instruments are not in use, the water sits inside the tubing. The small number of environmental bacteria naturally found in the water quickly multiply and cling to the walls of the tubing. A University of Louisville Dental School study, however, tested water from more than 60 dental offices across the nation. The report stated that organisms found in the water are environmental bacteria and generally not harmful to most people (see www.org/prof/prac/issues/topics/waterlines.html).

In other related news, Toronto dentists are playing catch-up to meet a new city requirement to stop flushing mercury into the sewer system, according to the Canadian Water Quality Association. Mercury, a nerve toxin that can cause learning disabilities in babies, makes up 50 percent of silver amalgam, the most common form of filling used by dentists. About one-third of all mercury in Canada’s sewer systems comes from dentists’ offices, about a kilogram per dentist annually. By June, they must have collection equipment that will reduce mercury dumping by 10 times the current allowable rate level of .01 milligram per liter of water.


GE forges ahead, snags BetzDearborn; Pall buys filtration division of USFilter
In a move that could add $1 billion in annual sales, GE Specialty Materials—a unit of General Electric Co.—has acquired the water treatment services business of BetzDearborn, of Trevose, Pa., from Hercules Inc. The $1.8 billion transaction, which is subject to regulatory approval, is expected to close in the spring. BetzDearborn is a global service company providing engineered chemical treatment of water and process systems in industrial applications. It’s the second largest industrial water treatment service business in the world. Globally, the water treatment business segment is a $6-billion opportunity. BetzDearborn has offices in more than 50 countries. It has four regional centers and 25 production plants located in North America, Asia-Pacific, Europe and Latin America. GE’s acquisition also largely ends Hercules’ short association with BetzDearborn, which Hercules purchased in 1998, paying more than double the company’s stock price at the time. “GE will be more aggressive in the future,” predicted Neil Berlant, senior vice president of Wells Fargo Van Kasper, a Los Angeles-based brokerage firm.

In other acquisition news, filtration systems maker Pall Corp., of East Hills, N.Y., said in mid-February that it agreed to buy the filtration and separations business of USFilter Corp., an indirect wholly owned subsidiary of Vivendi Environ-nement. (In 1998, USFilter appointed Andrew Denver as president of the division after the company had purchased Memtec Ltd., which he founded in Australia.) The amount of the deal is $360 million. Pall, at $270 million in sales annually, makes filtration products for separation and purification of liquids and gases for the food and beverage, industrial, biotechnology and pharmaceutical industries. It expected the transaction to be completed by April. “Pall has previously been discounted as not being a player in the business—they’re a player now,” said Berlant. Vivendi Environnement said the sale was part of its strategy to divest non-core assets and focus on its core environmental and water/wastewater businesses.

In other news, Neil Desmond, vice president and general manager of USFilter/Plymouth Products, acknowledged that Plymouth is also on the sales block. Plymouth, known for its AMETEK product line and located in Sheboygan, Wis., employs 400 people. Meanwhile, Vivendi chairman Jean-Marie Messier, under pressure from Wall Street and shareholders over a $13.3 billion write-off because of acquisitions made at the market’s peak (resulting in a 2001 $11.9 billion net loss) and revised accounting rules, suggested in a March 6 Reuters article that Vivendi Environnement may be “deconsolidated.” Jim Force, USFilter corporate communications director, said that’s currently limited to Plymouth and no further plans involve the Consumer and Commercial Products Group, which includes Culligan. “Certainly, Culligan is an active part of our business model and we plan to continue investing in and growing it,” Force said.

International

Coolers turn hot across Europe; POU market gears up for boom
The first study of Europe’s burgeoning point-of-use (POU) water cooler industry reveals growth of 57 percent last year to 123,000 units across 16 countries, according to Zenith International. The United Kingdom has the largest European POU presence with a 42 percent share and the greatest number of newly installed units in 2001. France is second and Ireland is a close third and the most established market with the highest number of units per person. Rates of growth varied widely across Europe, led by Germany where the market tripled in size, and four countries where installations at least doubled—Finland, Italy, Denmark and Switzerland. Zenith forecasts that the European POU market will experience annual growth rates between 25 percent and 40 percent, reaching in excess of 450,000 units in 2006.

Danone leery of U.S. market
In a recent interview, Chairman Franck Riboud of French food group Danone said he would not jeopardize the company’s margins by competing directly with Coca-Cola Co. and PepsiCo, which are aggressively moving into the bottled water market with the Dasani and Aquafina brands, respectively. While Danone is the world’s biggest bottled water producer in terms of volume with 12.5 percent of market share, it’s also competing against Switzerland’s Nestle in the United States. Riboud said Danone isn’t interested in being a niche market player. Instead, the company has staked its fortunes in emerging markets like Mexico, China and Indonesia, which Riboud sees representing 60 percent of future worldwide growth in bottled water as opposed to the projected 10 percent for the United States. Danone’s bottled water business, excluding home and office delivery, represents between 1.5 and 2.5 percent of group operating profit. In related news, the company reported in mid-February a steeper-than-expected drop in net profit last year vs. 2000.

Danaher buys Vividor
Hach owner Danaher Corp., of Washington, D.C., has acquired Viridor Instrumentation from Pennon Group Plc, of Exeter, U.K., for approximately $135 million. Viridor is a manufacturer of analytical instruments for drinking water, wastewater, ultrapure water and other fluids, and has annual revenues of about $75 million. It operates in eight countries including the United States.

Offices go up in Vietnam
Black & Veatch, of Overland Park, Kan., has been awarded two contracts that will substantially increase the company’s workload in Vietnam. To accommodate the additional workload, the company has opened new project offices in Ho Chi Minh City and Hanoi. The project, consisting of the rehabilitation and extension of irrigation infrastructure in five provinces of the Mekong Delta, will increase productivity of and exclude saline water from approximately 500,000 acres of agricultural land. Under the second contract, the company is performing a feasibility study and will develop preliminary designs for environmental improvements in the Tan Hoa-Lo Gom drainage catchment of Ho Chi Minh City. Black & Veatch Corp. is a leading global engineering, construction and consulting company specializing in infrastructure development in the fields of energy, water and information.

USFilter deals with Dead Sea
The city of Karamay’s (China) new wastewater treatment plant with USFilter’s technology has been in operation since November. In February 2001, the Foreign Economic Trading Corporation of Xinjiang Petroleum Administration awarded USFilter a $3.1 million contract to supply equipment for the plant. In other news, USFilter has received a contract from Dead Sea Works Ltd. for a hot leach crystallization system capable of producing 1.3 million metric tons per year of potassium chloride. The system is scheduled for start-up early next year.

Mexico plant earns standard
Eltec, Northland Motor’s manufacturing facility located in Juarez, Mexico, has earned ISO 9001 certification, the highest level in the ISO 9000 global standards system. As a result, Eltec is the first Northland plant outside the United States to receive this distinction. (Northland’s Watertown, N.Y., facility has been certified since 1996). Eltec manufactures series universal electric motors in sizes from fractional horsepower up to 5 horsepower, as well as 3.3 shaded pole induction motors. The Eltec facility has 215 employees as well as engineering, quality, accounting, manufacturing and materials staffs. Northland is a division of Scott Fetzer Co. Northland has been in the appliance, pump, pool and spa, lawn and garden, floorcare and power tool market.

ZENON finances new plant
ZENON Environmental said it has sold $37 million of its shares to a syndicate of underwriters led by Research Capital Corp. Proceeds of the offering will be used for financing the construction of the company’s second manufacturing facility in Hungary for the development and marketing of its point-of-entry water treatment product, and the balance for general corporate purposes.

India to host major event
Science & Technology India 2002, India’s first major annual international exhibition and conference, will focus on cost-effective, innovative and user friendly technologies in the areas of environment, water, industrial automation and instrumentation. The event will take place on April 10-12 in Pragati Maidan, New Delhi, India. The show will be organized by Exhibitions India.

Vivendi posts revenue spike
French water-to-media conglomerate Vivendi Universal said in February that its revenue rose 9.7 percent to $50 billion in 2001 vs. $46.3 billion a year earlier led by the solid performance of its telecoms and environment services operations. Revenue from Vivendi Environnement, the water and waste management group in which Vivendi owns a 63 percent interest, rose 11 percent to $25.4 billion vs. $22.94 billion in 2000.

Letters

Friday, April 19th, 2002

Staying abreast of UV updates important to readers

Dear Editor:
The answer in the WC&P “Ask the Expert” Column, February 2002, p. 18 (“Distilled vs. reverse osmosis”), contains some outdated information. Regarding ultraviolet light (UV), the column acknowledges recent advances in our appreciation of UV’s effectiveness, but leaves standing the statement that protozoa (Giardia and Cryptosporidium) are “relatively resistant to UV”… This misunderstanding of UV’s inadequacy as a disinfectant of protozoa was widely held until recently. In fact, it’s only been until the last five years when researchers discovered otherwise that UV has been acknowledged as extremely effective against these parasites, even more so than against most bacterial cells. This efficacy has led the USEPA to focus on UV as a major tool for compliance with its proposed Long Term 2 Enhanced Surface Water Treatment Rule (see www.epa. gov/safewater/mdbp/lt1eswtr.html and www.epa.gov/OGWDW/lt2/lt2_ reglanguage.pdf) for control of Giardia and Cryptosporidium. Utilities around the country and in Canada are presently evaluating, designing, and installing UV systems for this very purpose. The old dogma that UV does not affect protozoa might still find its way into print here and there, but the drinking water industry has welcomed the new research that shows UV to be a by-product-free disinfectant of these problematic microbiological contaminants.

Thomas Hargy, Senior Scientist
Clancy Environmental Consultants, Inc.
St. Albans, Vt.

More than a ‘Western’ outlook

Dear Sirs:
We have the pleasure of renewing our subscription for two years. Please continue dispatching your informative, if substantially “Western”-based magazine. This is not a criticism, but as is so often the case with specialist publications, the magazine leans heavily towards Western problems, and little is mentioned as regards Africa or areas where severe water cleansing problems exist. Thank you all the same for a generally informative product.

G.F. Turner, General Manager
Aquifer Ltd. Water &Power
Mombasa, Kenya

Editor’s note: Thank you very much for your continued interest in WC&P. While we are based in the United States, we’ve been proud of expanding the magazine’s focus to encompass a more global outlook—even adding “International” to the publication’s masthead with our September 2001 issue. This was four years after launching our monthly “World Spotlight” column and dedicating our September issue almost exclusively to global issues. In tabulating the number of articles that focus on topics outside the United States, we came up with a list more than eight pages long since 1997. This doesn’t include our news briefs section “International Focus.” We readily admit that articles on subjects in Africa are more difficult to arrive at, but not for lack of trying. If you or anyone else that’s a water professional or otherwise involved in improving the quality of water in Africa is interested, we would be more than happy to entertain publishing articles you would care to write. It could be a case study, general technical article or a review of any number of issues related to a particular nation’s water treatment network. Point-of-use/point-of-entry drinking water application articles are, of course, preferred. Even if you’d like to just submit small news releases about your company, your staff and your products, all submissions are welcome. It’s likely easier and more timely to fax or email them. Stay in touch.

Growth Alert: U.S. Cleans Up With Bioremediation Markets

Friday, April 19th, 2002

By Karen Rasmussen

According to several recent studies, the overall market size in the United States for hazardous materials contaminated site remediation falls between $7-to-8 billion annually. Demand for these services is mainly driven by government entities such as the U.S. Department of Energy, Department of Defense, U.S. Environmental Protection Agency (USEPA), related state agencies under the auspices of the Resources Conservation and Recovery Act (RCRA), Superfund site projects, and underground storage tank regulations. Although there are several innovative technologies available to alleviate these environmental problems, one of the fastest growing areas is bioremediation.

Description
Bioremediation is a versatile treatment process that accelerates the biological cleanup process undertaken by naturally occurring microorganisms (yeast, fungi or bacteria) to break down hazardous substances into less toxic or nontoxic substances. Microorganisms eat and digest organic substances for nutrients and energy. Certain microorganisms can digest organic substances such as fuels or solvents that are hazardous to humans. The microorganisms break down the organic contaminants into harmless products—mainly carbon dioxide and water.

Application
Biological remediation tends to be a relatively inexpensive option because it’s employed as an in situ method and doesn’t require significant labor costs or energy inputs. According to the USEPA, biodegradation is useful for many types of organic wastes and is a cost-effective, natural process. Many techniques can be conducted onsite, eliminating the need to transport hazardous materials. The applications for biodegradation heavily depend on the toxicity and initial concentrations of the contaminants, their biodegradability, properties of the contaminated soil, and the particular treatment system selected.

Contaminants targeted for biodegradation treatment are non-halogenated volatile organic chemicals (VOCs), semi-volatile organics (SVs) and fuels. The effectiveness of bioremediation is limited at sites with high concentrations of metals, highly chlorinated organics or inorganic salts because these compounds are toxic to the microorganisms. A standard application for bioremediation is the cleanup of petroleum hydrocarbons such as benzene, toluene, ethyl benzene and xylene (BTEX), and other contaminants such as methyl tertiary butyl ether (MTBE), ammonium perchlorate, trichloroethylene (TCE), tetrachloro-ethene (PCE), and many pesticides and herbicides. Biological remediaton is also useful in the treatment of mineral oil and aromatics.

Future
The biological treatment market is made up of several smaller firms that employ less than 50 people. Although there has been significant consolidation in the remediation services industry overall, manufacturers of bioremediation technology tend to be somewhat fragmented having entered the market with specific biological expertise. Since it has become essential for larger engineering and consulting firms to provide a diversified product line, bioremediation has become a part of their offerings as well.

With the significant growth of the U.S. bioremediation market, and the European bioremediation market projected at $119 million in 2003, it’s clear that there has been a greater acceptance by end-users and regulators for these technologies as their advantages become better understood. As biological treatment is one of the less expensive technologies (because, again, it’s generally in situ and involves little or no energy input), it’s expected to become more popular as time progresses. Prices are subsequently expected to become even more competitive with other technologies, thus making the cost of bioremediation one of the largest drivers for the technology’s growth.

Additionally, there are several organizations and government entities advancing the research of this technology while trying to make it more appealing to end-users. For example, the Energy Department (DOE) does a great deal of bioremediation research with the natural and accelerated bioremediation program (NABIR)—see http://www.lbl. gov/NABIR/. In 2000, the budget for this well-coordinated, comprehensive research program was $25 million. Along with the DOE’s efforts in furthering quality research, bioremediation scientists are searching for cost-effective technologies to improve current remediation methods to clean up DOE’s contaminated sites.

Conclusion
This research was conducted in 2001 and will continue into the future, leading to new discoveries for reliable methods of bioremediation of metals and radionuclides as well as organic pollutants in soils and groundwater. The NABIR program is unique in that it supports the basic research that’s needed to understand this technology and to more reliably develop the practical applications for cost-effective cleanup of pollutants at DOE sites. With this initiative by the DOE and increasing acceptance of these technologies, bioremediation is likely to have a promising future in the United States and around the world.

References

  1.  USEPA, “National Summary of Unregulated Contaminants in Public Water Systems,” EPA 815-P-00-002, January 2001, or website: http://www.epa.gov/safewater/standard/ucmr/draft_summary.pdf
  2. USEPA, “Factoids: Drinking Water and Ground Water Statistics for 2000,” June 2001 website: http://www.epa.gov/safewater/data/00factoids.pdf
  3. USEPA, “Burden and Cost Calculations for the Unregulated Contaminant Monitoring Regulation (2000-2005),” March 1999, website: http://www.epa.gov/safewater/standard/ucmr/ucmrc1.pdf

About the author
Karen Rasmussen is the industry manager of the Environmental Research Group at Frost & Sullivan and is responsible for business planning, strategy, development and implementation. Rasmussen graduated from Menlo College with a bachelor’s degree in business administration. If you would like more information about this article, please contact Cynthia Cabral at (210) 247-2440, (210) 348-1003 (fax) or email: ccabral@frost.com

Getting Ready for Spring: Water in an Emergency

Friday, April 19th, 2002

By Chris Floyd

Summary: The following article is reprinted here with the permission of the American Red Cross. It’s presented as something that water treatment dealers can pass on to their customers during the upcoming flooding, tornado and hurricane seasons. The original article, written last year, can be found at www.tallytown.com/redcross


If a hurricane, winter storm or other disaster strikes your community, you might not have access to food, water and electricity for days, even weeks. We all know that water is a survival priority and by taking time now to store an emergency supply, you can provide for your entire family in a disaster situation.

An ample supply
You must have an ample supply of clean water—at least one gallon per person per day. You should store, at minimum, a two-week supply for each member of your family. You will need this water for drinking, food preparation and hygiene. Store your water in thoroughly washed plastic, glass, fiberglass or enamel-lined metal containers. Never use a container that has held toxic substances. Plastic containers, such as soft drink bottles, are best. Seal water containers tightly, label them, and store in a cool, dark place. Rotate water every six months.

If, for some reason, disaster catches you without a stored supply of clean water, you can use the water in your pipes, hot-water tank and ice cubes. As a last resort, you can use water in the reservoir tank of your toilet (not the bowl). To use the water in your pipes, let air into the plumbing by turning on the faucet in your house at the highest level. A small amount of water will trickle out. Then obtain water from the lowest faucet in the house. To use the water in your hot-water tank, be sure electricity or gas is off, and open the drain at the bottom of the tank. Start water flowing by turning off the water intake valve and turning on a hot-water faucet. Do not turn on the gas or electricity when the tank is empty. If you have time before the event, you can also fill the bathtub and/or sink with water.

You can find water outside your home from the following sources—rainwater; streams, rivers and other moving bodies of water; ponds; lakes and natural springs. This water must be purified for drinking purposes. Avoid water with floating material, an odor or dark color. Use saltwater only if you distill it first. You shouldn’t drink floodwater.

How to purify water
You should purify all water of uncertain purity before using it for drinking, food preparation or hygiene. There are many ways to purify water. None is perfect. Often the best solution is a combination of methods. Boiling and disinfecting are two methods that will kill most microbes in water. Distillation is a more thorough method as it removes the microbes that resist boiling and disinfecting. It also removes heavy metals, salts and most other chemicals.

Boiling is the safest method of purifying water. Bring water to a rolling boil for 3-5 minutes, keeping in mind that some water will evaporate. Let the water cool before drinking. Boiled water will taste better if you put oxygen back into it by pouring the water back and forth between two clean containers. This will also improve the taste of stored water.

Disinfecting involves using household liquid bleach to kill microorganisms. Use only regular household liquid bleach that contains 5.25 percent sodium hypochlorite. Don’t use scented bleaches, color-safe bleaches or bleaches with added cleaners. Add 16 drops of bleach per gallon of water, stir and let stand for 30 minutes. If the water doesn’t have a slight bleach odor, repeat the dosage and let stand another 15 minutes. Again, the only agent used to purify water should be household liquid bleach. Other chemicals—such as iodine or water treatment products sold in camping or surplus stores that don’t contain 5.25 percent sodium hypochlorite as the only active ingredient—aren’t recommended and shouldn’t be used.

Distillation involves boiling water and then collecting the vapor that condenses back to water. The condensed vapor will not include salt and other impurities. To distill, fill a pot halfway with water. Tie a cup to the handle on the pot’s lid so that the cup will hang right side up when the lid is upside-down (make sure the cup is not dangling into the water) and boil the water for 20 minutes. The water that drips from the lid into the cup is distilled.

Conclusion
If supplies run low, never ration water. Drink the amount you need today, and try to find more for tomorrow. You can minimize the amount of water your body needs by reducing activity and staying cool.

About the author
Chris Floyd is disaster services director of the Capital Area Chapter of the American Red Cross in Tallahassee, Fla.

In the Aquarium with Ozone: A Matter of Living Clearly?

Friday, April 19th, 2002

By John M. Overby

Summary: Unlike most water treatment applications, aquariums need to preserve the many living organisms existing in the water. Over the years, ozone has become a viable alternative to producing desired results. Some of the reasons are given here.


Ozone has been widely used for drinking water and wastewater applications for many years and has gained acceptance in the water industry as an alternative to chlorine. For some drinking water facilities, an ozone system can be produced with minimal problems. A wastewater ozone project can be designed as well with careful testing and planning. Aquarium water treatment requires both aspects of water treatment—drinking water and wastewater.

Water circulating around an aquarium facility is recycled through a series of treatment steps. These not only treat the influent wastewater but disinfect and clean the water prior to sending it back to the facility. The typical aquarium facility doesn’t have the luxury of using a flow-through system of municipal clean water. The typical aquarium facility can’t fill and dump the water based on its quality. If the waste was removed continuously via a flow to sewer, fresh water would have to be always flowing, causing great expense. Given that water in a typical aquarium facility is turned over every one-to-four hours, the amount of wastewater dumped down the drain would be astronomical. The aquarium facility tries to recycle the water through a life support system (LSS) with a 100 percent recovery rate. This total reuse of water requires careful attention to the water treatment equipment.

The life support system is a crucial element of all animal habitats. The LSS controls and balances the total water chemistry of a system and maintains its viability to sustain life for the fish and marine mammals. To do this, the LSS is designed to receive water (salt or fresh) from the aquarium facility through a series of surface skimmers and bottom drains, and deliver it to the LSS to transform the wastewater into pure water. The LSS for a multi-species marine system has to be designed to perform a number of functions. These functions are water flow dynamics, particulate waste removal (filtration—mechanical and chemical/biological), disinfection and temperature control.

Water flow dynamics
The water turnover rate of a typical aquarium facility varies depending on treatment objectives (primarily water quality). At 1-4 hours, this means that in a 100,000 gallon facility the water would get pumped at a rate of 1,666 gallons per minute (gpm). This is a constant rate that needs to be running 24 hours a day, 365 days a year. Energy cost to transport this volume of water is a critical concern and is factored into the design of a system.

The introduction of filtered system water into the exhibit(s) area is done in a manner that will ensure proper flow dynamics and is a very important part of the architectural design of the aquarium. It’s crucial that the marine life’s waste products are swept away from the system into the skimmers and bottom drains, and the return water is properly distributed back to the exhibit.

Mechanical filtration
Mechanical filtration in the LSS is designed to primarily remove particulate matter; sand pressure filters are most commonly used. These consist of closed vessel(s) containing a quantity of sand held above a supporting underdrain assembly. Water is normally pumped into the vessel passing through the sand, which strains and retains particulate matter (to about 20 microns). As the sand becomes clogged, an increase in pressure across the filter bed can be noted due to the build-up of particles. When the manufacturer’s prescribed level (pressure drop) for cleaning the filter bed has been reached, the filter flow is reversed and the dirt and water used for the cleaning operation are diverted to waste or collection for backwash reclaim. Once the water washing the filter bed appears to run clean, the system flow is returned to normal and continues to filter the pool’s water.

Chemical/biological filtration
In addition to removing particles, other water constituents need to be treated. Some of the main contaminants are ammonia, dissolved organic compounds and dissolved gases (CO2, O2, etc). Biological filtration takes care of ammonia (NH3) or nitrogen dioxide (NO2) and converts it into less toxic nitrogenous compounds such as nitrate (NO3) or nitrogen gas (N2). This is accomplished through the chemical action of bacteria living on a suitable substrate such as a gravel bed or plastic packing media. Dissolved organic compounds are typically removed with a carbon filter, ozone injection or a foam fractionator. The foam fractionator is a method in which foam is created by gas injection into the water while the foam carries away the waste.

Disinfection
Disinfection of LSS is generally found at the end of a filtration system to improve the quality of water. Ozone is typically introduced into a 10-15 percent side stream of the filtration water. The side stream percentage is determined based on the ozone-desired dosage and equipment of choice. The disinfected ozone side stream is carefully monitored and returned back to the filtration flow.

Ozone is utilized as the primary disinfectant in multi-species marine and freshwater systems. Ozone, with its high oxidation-reduction potential, is the most effective and efficient disinfectant that can be employed. Dissolved ozone inactivates cell membranes of a wide range of bacteria, viruses and protozoa. Its highly reactive nature guarantees that it’s short-lived and consumed within the treatment process. Deaeration equipment ensures that no harmful residual ozone is sent back to the systems and controls saturation of the gas in the water. This is how aquatic systems can allow the coexistence of mammals and fish in the same water. Without an active residual in the water, the health of the fish is maintained while the bacteria (from animal waste) is controlled.

Lightning storm in a can
Flowing clean, dry air or oxygen through high voltage corona discharge chambers produces ozone. Most high output ozone generators are equipped with enriched oxygen source gas equipment to increase the concentration of the ozone gas. Ozone gas is injected into the side stream through a venturi, which operates under negative pressure and dissolves the ozone in the water stream via the high surface area bubbles that are created in the venturi’s orifice. The gas and liquid mixing is done under pressure to ensure the high ozone dissolution.

In salt water systems there will be a significant amount of bromide ion present. Bromide reacts very quickly with ozone to form hypobromous acid and bromine by-products. This residual, if it’s high enough, could have a significant toxic effect on the fish. Careful design needs to be implemented to ensure against this. System design can prevent mortality by carefully monitoring ozone addition and by providing carbon filtration for removal of the potentially harmful bromine by-products. Water quality monitoring determines when the activated carbon has become exhausted and needs to be replaced.

The temperature of the water may need to be regulated and controlled according to season. Chillers keep the water from becoming too warm during the summer months, while heaters can warm the water in the winter. Aquarists and life support operators control the temperature settings according to a yearly schedule that closely replicates temperatures in the natural environment.

The treatment of a water system in an aquarium environment is no easy task. The LSS needs to not only treat incoming wastewater but needs to produce a high quality disinfected water for return to the facility (24 hours a day). Careful system design and monitoring is therefore required. 


Ozone evolution in aquarium water treatment
Ozone for aquarium water treatment use was very limited in the ’60s and early ’70s. In the early ’70s, consulting engineers remained skeptical about its use—although based on European success—the attitude changed and ozone began gaining popularity. The main stumbling block was in limited knowledge of ozone applications and equipment durability. The time was right for market growth and the big problems were in equipment, materials of construction, and the general knowledge in design.

During the mid and late ’70s, there were many advances made in air preparation equipment, construction materials as well as understanding reactor kinetics of ozone for water treatment. This was a big breakthrough for ozonator manufacturers in that they could offer an ozone system rather than just an ozonator, and leaving the rest up to the design of the consulting engineers.

In the early ’80s, ozone came to fruition as the reagent of choice for maintaining healthy fish communities and vastly improving the water quality. Ozone systems required large footprint space and height requirements (typically 20 feet) while utilizing much of the limited valuable land.

In the early ’90s, the general population became conscious of the sharp decline of species and prompted the zoological parks and aquariums to move ahead. They had a good funding base and people were willing to pay the bill via gate receipts. Ozone manufacturers improved the design of their equipment and produced ozone through a lower cost per unit ($/lb) production. Ozone contacting was refined and allowed much higher ozone utilization for a given water treatment objective.

The late ’90s produced ozone equipment refinement and improvement in production capacity, cost and reliability. The ozone contacting kinetics was fine-tuned and provided 95 percent ozone utilization. The system space and height requirements were minimized and more valuable land was available to be used more effectively. The compactness and effectiveness of the conventional ozone system requires much higher safety monitoring than was previously required.

The knowledge of highly trained LSS design engineers must be utilized in any facility design or modification. Organizations such as the American Zoological Society offer accreditation for facility LSS operation and organizations such as the Aquatic Animal Life Support Organization (AALSO) offer an excellent exchange of information. Knowledge and communication are imperative to secure the future for ozone in the aquarium market.


Conclusion
Today, equipment is designed to produce ozone with concentrations of six-to-10 times greater ozone capacity than 10 years ago with ensured reliability. The use of ozone equipment in the aquarium market has advanced markedly in performance, reliability and capability for successful gas/liquid contacting. Still, the next five years will be a continued learning curve for the aquarium users of ozone systems. The more potent ozone gas production combined with oxygen feed gas requires important design reviews and constant monitoring of new and retrofitted systems. The ozone generation system design of years past is no longer valid and new criteria need to be established and closely monitored.

About the author
John M. Overby, of Phoenix-based Ozone Water Systems Inc., has been involved in the ozone industry for the past 10 years. He holds a bachelor’s degree in chemical engineering from Arizona State University. Overby can be reached at (480) 421-2400 or email: overby@ozonewatersystems.com

Meeting the New Arsenic Standard with a New Iron-Based Adsorbent Media: POU Applications

Friday, April 19th, 2002

By Gary L. Hatch

Summary: POU drinking water treatment units that utilize this new granular ferric hydroxide adsorbent can offer small community water systems an economical solution for effective removal of As III and As V to meet the new USEPA arsenic standard.


On Nov. 26, 2001, President George W. Bush signed legislation reaffirming the lowering of the arsenic maximum contaminant level (MCL) from 50 parts per billion (ppb) to 10 ppb. Many community water systems (CWSs) in the United States will now have until Jan. 23, 2006, to implement an economical treatment solution. The effective date of this rule1 was Feb. 22, 2002, and the effective date for purposes of compliance with the new consumer confidence rule reporting requirements for arsenic is the same. The U.S. Environmental Protection Agency (USEPA) estimates that of those CWSs in violation, 97 percent serve less than 10,000 people.

BAT and small systems
In anticipation of the lower MCL, many studies have been conducted in the last few years to evaluate various municipal treatment technologies. These studies have resulted in seven processes being selected by USEPA1 for designation as best available technologies (BATs) for removal of arsenic from drinking water. These include:

It’s significant to note that in order for these listed BATs to be optimally effective, arsenic must be in the +5 oxidation state (As V, pentavalent arsenic or arsenate). If arsenic is present in the +3 oxidation state (As III, trivalent arsenic or arsenite), it must be oxidized to As V utilizing an appropriate oxidant, e.g., free chlorine, permanganate or ozone2. The rule also states that CWSs aren’t required to use BATs to achieve compliance and states: “Any technology that is accepted by the State primacy agency and achieves compliance with the MCL is allowed.”

While these studies have focused principally on the above BAT technologies as applied to centralized municipal processes, some point-of-use (POU) treatment technologies (RO and activated alumina fixed-bed adsorbers) were also evaluated. This is in accordance with the 1996 reauthorization3 of the Safe Drinking Water Act (SDWA) that does allow use of POU and point-of-entry (POE) technologies to meet the arsenic MCL. The POU/POE devices, however, must be under the control of the CWS and it must be demonstrated to the primacy agency that the remedial program provide protection at least as well as centralized treatment. Small system compliance technologies (SSCTs) listed in the rule include undersink RO and activated alumina POU devices. The use of SSCTs vs. centralized BAT will depend on the cost of treatment per household as determined by the authorized technology provider and the primacy agency. Small systems are defined as those serving less than 10,000 people.

Treatment options
As indicated from the aqueous chemistry of arsenic, the oxidation state of arsenic and the pH of the contaminated water must be known before an appropriate removal technology is selected. For instance, RO would best be utilized for As V removal over a wide pH range since the membrane would reject the negatively charged arsenate species (H2AsO4-1 and HAsO4-2). Conversely, As III—which exists as an uncharged species (H3AsO3)—would be poorly rejected since most RO membranes are poor at rejecting neutral molecules. Also, alumina, iron-doped alumina and ion exchange would be more effective for removing As V than As III (for an optimum bed size and flow rate) because the negatively charged species of As V are better complexed and retained by the adsorptive or ion exchange media. Arsenic speciation methods4,5 are available for determining which form(s) of arsenic are present in contaminated water.

Granular ferric hydroxide
A number of different granular adsorptive media were tested in this study for determining the most effective adsorbent for POU applications. Among these were several iron-doped alumina (natural and synthesized), iron-doped activated carbon and a specific form of granular ferric hydroxide. This study revealed that the new adsorbent far outperformed all the other media tested.

Proposed NSF Test Protocol
An arsenic reduction protocol for testing POU drinking water treatment devices is being developed by NSF International for incorporation into ANSI/NSF Standard 53: Drinking Water Treatment Units—Health Effects. Separate protocols are being developed for As V reduction and As III reduction. The proposed test parameters for these protocols are shown in Table 1.

The general background test parameters are based on data from the U.S. Geological Survey’s groundwater survey6 and the 50 ppb arsenic feed concentration represents the 97th-percentile arsenic occurrence level, which means that 50 ppb or less was found in 97 percent of the drinking water samples surveyed.

The proposed As III test conditions simulate groundwater at pH 6.5 with trace levels of soluble iron, manganese and dissolved oxygen (DO). Groundwater at pH 8.5 typically doesn’t have soluble iron and manganese. For a “total” arsenic reduction claim, the proposed standard would require testing for both As V and As III at pH 6.5 and 8.5. Testing at both pHs was necessary because of the potential effect of pH on arsenic adsorption for the various adsorptive media expected to be utilized. Also, testing at an arsenic feed concentration of 300 ppb or greater would be allowed. The 300 ppb concentration represents the level of arsenic found in a majority of the sources above 50 ppb in this survey.

The cartridge configuration chosen for this study is one that could easily be utilized for POU application. It’s a canister-type cartridge designed for an up-flow mode of operation. Table 2 lists the cartridge dimensions and the other operational parameters used in these tests.

Evaluating the results
Figures 1-4 show the results obtained and demonstrate the very efficient performance of the new granular ferric hydroxide adsorbent for removing As V and, somewhat surprisingly, also for As III with an empty bed contact time of only 10.6 seconds.

EBCT = Total Bed Volume of Empty Cartridge ÷ Volumetric Flow Rate
Example: Cartridge Bed Volume = 400 mL (0.106 gallons)
Volumetric Flow Rate = 0.6 gallons per minute
EBCT = 0.106 ÷ 0.6 = 0.176 minutes = 10.6 seconds

For As V removal at pH 8.5 in Figure 1, gradual breakthrough begins at about 300 gallons and a final breakthrough capacity (@ 10 ppb) is observed at about 700 gallons. Of all the other materials tested in this study, the highest capacity obtained under the same conditions was only 325 gallons. All feed concentrations in this study were targeted at 50 ppb. The feed and effluent samples containing As III were speciated4 to verify that oxidation of As III to As V hadn’t occurred.

The results in Figure 2 were obtained at pH 6.5 and note that all effluent samples were reported at less than 0.5 ppb As V. The capacity for this small cartridge (400 ml bed volume) at low pH appears to be far in excess of 1,000 gallons. This remarkable efficiency for As V removal by the new granular ferric hydroxide adsorbent at lower pH indicates that for larger scale removal processes, pH adjustment may be an option for achieving very high operating capacities.

Because of operational difficulties maintaining low dissolved oxygen (DO), Fe++ and Mn++ at pH 6.5, As III removal tests weren’t performed exactly to the proposed NSF protocol (low DO and with Fe+2 and Mn+2 at pH 6.5). Under the conditions utilized, however, the adsorbent was very effective for removing As III at both pH 8.5 and 6.5 (see Figures 3&4). The capacity (~1,000 gallons) at pH 8.5 shown in Figure 3 is only slightly less than the capacity obtained at pH 6.5 (~1,150-1,200 gallons in Figure 4). It’s important to note that the As III removal capacity at pH 8.5 is approximately 300 gallons greater than the As V removal capacity at pH 8.5. The effect of high pH on the adsorbent apparently doesn’t impact the adsorption mechanism of As III (as H3AsO3) as much as that for adsorbing As V (as H2AsO4-1 and HAsO4-2). The poorer adsorption of As V than As III at high pH is apparently caused by a more negative surface charge that exerts greater repulsion of the negatively charged H2AsO4-1 and HAsO4-2.

These results show that the new granular ferric hydroxide adsorbent:

  • Removes As V far better than all the other media tested,
  • Removes As V extremely well at pH 6.5,
  • Removes As III at pH 6.5 and 8.5 better than As V at pH 8.5, and
  • Exhibits minor pH dependency for As III removal.

The adsorbent’s high affinity for As III is significant since most other media and removal processes reduce As V more efficiently than As III, e.g., RO and ion exchange. These technologies would require pre-oxidation of As III to As V to be effective (e.g., USEPA BAT requirement mentioned above).

Cost considerations
According to the results presented, an affordable undersink POU device with a cartridge similar to the one used in this study containing the adsorbent could provide a reasonable capacity³ (500-1,000 gallons) for arsenic reduction. Such units could consist of a single-housing unit with or without a flow capacity monitor or a two-housing unit without a monitor, depending on the desired claimed capacity. The cost of such devices would fall well within the $150-200 price range mentioned in a recent WC&P article.7

Conclusion
The new granular ferric hydroxide adsorbent far outperforms all other adsorbents studied.

  • Under equivalent background conditions, the adsorbent removes As III at both pH 6.5 and pH 8.5 better than As V at pH 8.5.
  • Overall, under the conditions studied, these data indicate that the adsorbent removes As V at pH 6.5 much better than As III at both pH 6.5 and pH 8.5, and As V at pH 8.5. The relative adsorp-tivity of arsenic can be expressed as:
  • As V @ pH 6.5 > As III @ pH 6.5 ≥ As III @ pH 8.5 > As V @ pH 8.5
  • Under the conditions studied, As III removal is less pH dependent than As V removal.
  • These observations suggest that when utilizing the adsorbent, pre-oxidation of As III to As V may not be necessary (depending on initial pH and competitive costs of pH adjustment vs. pre-oxidation).
  • The proposed NSF synthetic test water for As V was found to be stable relative to maintaining the As V feed concentration, relatively easy to make and gave repeatable test results within the parameters of these tests.
  • The proposed NSF synthetic test water for As III was unstable relative to maintaining dissolved oxygen (DO), pH @ 6.5, iron and manganese (data not presented). Further work is necessary to determine how these parameters can be added and/or controlled.

POU drinking water treatment units that utilize this adsorbent can offer small community water systems an economical POU solution to meeting the new USEPA arsenic standard for arsenic contamination up to 50 ppb as allowed by the 1996 Safe Drinking Water Act.

References

  1. Federal Register, 66 (14), January 22, 2001, pp. 6976-7066, “National Primary Drinking Water Regulations; Arsenic and Clarifications to Compliance and New Source Contaminants Monitoring-Final Rule.”
  2. Laboratory Study on the Oxidation of Arsenic III to Arsenic V, EPA/600/R-01/021, March 2001 (available online at http://www.epa.gov/ORD/publications/ordpubs.html)
    3. Safe Drinking Water Act, August 6, 1996, Sec. 105: [1412(b)(4)(E)]; http://www.epa. gov/safewater/sdwa/test.html
    4. Edwards, M., et al., “Considerations in As Analysis and Speciation,” Journal American Water Works Association, 90(3), March 1998.
    5. Clifford, D., and C.C. Lin, “Arsenic (III) and Arsenic (V) Removal from Drinking Water in San Ysidro, N.M.,” National Technical Information Service, Springfield, Va.; EPA/600/S2-91/011, Cincinnati, 1991.
    6. Personal Communication, NSF International, ANSI/NSF Standard 53-Arsenic Task Group Meeting, September 2000.
    7. Gilles, Greg, “Arsenic Reduction for POU—Undercounter Options,” WC&P, 43 (10), 96-101, October 2001.

About the author
Gary L. Hatch, Ph.D., is director of research and development for USFilter Consumer & Commercial Water Group, of Sheboygan, Wis. GFH™ (granular ferric hydroxide) is a trademark of Culligan International Corp., of Northbrook, Ill. He is responsible for new product R&D including the development of POU products utilizing the adsorbent described in the article. Hatch graduated from Kansas State University with a doctorate degree in analytical-inorganic chemistry and has been actively involved in water treatment for the past 28 years. He can be reached at (920) 451-9353, (920) 451-9384 (fax), email: ghatch@plymouthwater.com, or website: www.culligan.com or www.usfilter.com

Microbial Waterborne Disease: Are We at Risk?

Friday, April 19th, 2002

By Kristina D. Mena

Summary: Risk assessments for microbiological contamination in various water sources are vital to protect public health. Using USEPA’s recommended level of acceptable risk, different studies use different pathogens as central components. According to the author, this practice needs to continue to fully ensure public safety.


Despite current water treatment advancements, microbial waterborne disease continues to occur in the United States. This may be due to a temporary breakdown in water treatment or water contamination after treatment. Exposure to contaminated drinking water by a community may lead to a recognizable outbreak of disease; however, these cases represent only a fraction of the total associated with waterborne microorganisms. Often, such cases are undetected; the ill person may not seek medical treatment, for example, or perhaps the source pathogen isn’t identified. Epidemiological data—on the causes, distribution and control of disease in populations—obtained from waterborne outbreaks provide information on human health impacts of microbial-contaminated water. It is, however, difficult to understand the public health significance associated with frequent exposure to low levels of contamination. A risk assessment methodology (based on the framework developed by the National Academy of Sciences1) has been developed and applied to predict human health consequences from exposure to pathogens in the environment, including water.2-5 Policy makers can use information obtained from a risk assessment to establish guidelines that address microbial water quality issues, and the U.S. Environmental Protection Agency (USEPA) first used risk assessment to develop the Surface Water Treatment Rule for Giardia.6

Monitoring for coliform bacteria, as indicators of microbial water quality, has proven to be inadequate at assuring treatment efficacy for pathogens and preventing waterborne outbreaks.7 Laboratory studies show no correlation between absence of coliform bacteria in water and absence of other (potentially disease-causing) microorganisms, such as enteric viruses and protozoan parasites. Using available data on specific pathogens, risk assessment is used to predict their public health impact. There are four steps to the risk assessment process—hazard identification, dose-response assessment, exposure assessment and risk characterization. In the hazard identification step, a microorganism is investigated to characterize it as a pathogen. Laboratory data and any available epidemiological data are evaluated to determine the microorganism’s ability to cause disease as well as describe all possible health outcomes resulting from exposure. Other issues addressed here include microorganism transmission routes, and the role of host factors such as immunity and response to multiple exposures. Table 1 lists some waterborne microorganisms whose roles as “hazards” could be evaluated in a risk assessment.

Using different studies
Dose-response assessment involves determining the relationship between dose of the microorganism (hazard) and the incidence or extent of the adverse health effect. This step may use data from animal or human studies (depending on what’s available) that may have used infection or illness as a health endpoint. If animal studies were used, extrapolation from animals to humans is required. It’s also necessary to extrapolate from high to low doses since relatively high concentrations of microorganisms are used in dose-response studies involving healthy human volunteers so high frequencies of infections can be observed with a minimum number of study participants. Mathematical models that may represent a microorganism-host interaction have been described elsewhere2 and two models in particular were shown to adequately reflect the infection process (see Table 2).

Several assumptions are made when using these models. It’s assumed a person is exposed to a random distribution of pathogenic microorganisms and one microorganism is capable of initiating infection. It’s also assumed each exposure is statistically independent of another. The appropriate model is selected using the method of maximum likelihood to determine which best fits the dose-response data for a particular microorganism. Parameters are subsequently defined.2 If illness and death are health endpoints in question, morbidity and mortality ratios (obtained through the hazard identification step) can be incorporated in the model to determine these probabilities. Annual risks can be determined (assuming a person is exposed to a constant amount of microorganisms daily) using the following equation:

Annual Risk of Infection (Pannual) = 1 – (1 – Pi)365

Setting the goal
The goal of exposure assessment is to determine the amount of water (such as drinking water) a person consumes as well as the number of microorganisms in the water. The USEPA uses a 2 liters per person per day (2 L/person/day) exposure for drinking water.8 To estimate exposure to microorganisms, a review of published literature describing occurrence studies of specific microorganisms in water can provide quantitative data. Unfortunately, this type of information is lacking for microorganisms in water. A microorganism’s ability to survive environmental stressors and its susceptibility to inactivation by water treatment are also considered here. Exposure assessment also distinguishes the population exposed, such as size and age distribution of population, for example.

Risk characterization uses information obtained from the previous steps to estimate health risks associated with exposure to a particular microbial hazard. All assumptions and uncertainties (such as dose, exposure frequency, population affected, etc.) that contributed to the risk assessment procedure are described here. The probability of becoming infected, ill or even dying after consuming various amounts of a particular pathogen can be estimated by using the appropriate model in Table 2.

Risk assessment has been conducted for specific waterborne microorganisms, such as rotavirus and Giardia.9,10 One study found rotavirus to be the most common cause of viral gastroenteritis worldwide and expressed the highest infectivity of any waterborne virus. Several waterborne outbreaks were associated with fecal contamination or inadequate water treatment. The beta-Poisson model with defined dose-response parameters for rotavirus was used in this assessment.4 Concentrations of rotavirus detected in drinking water and surface waters [assuming water treatment achieved 99.99 percent (4-log) reduction11] were obtained and used in calculating human health risks associated with drinking water exposure. The USEPA recommends annual risks of infection for waterborne microorganisms not exceed 1 in 10,000.12 When calculating risks for rotavirus in drinking water (assuming 2 L/person/day exposure) where polluted surface waters were the source and a 99.99 percent reduction of viruses was assumed, annual risk of infection didn’t meet this recommendation of infection greater than 1 in 1,000. The authors concluded that to meet USEPA’s 1 in 10,000 goal, 5 to 6 logs of virus removal would be necessary.

Determining acceptable risk
Another group developed a risk assessment model to estimate risk of infection after exposure to treated waters contaminated with different levels of Giardia cysts. Giardia is considered the most identifiable waterborne agent in the United States13,14 and is associated with a long duration of diarrhea in infected individuals. Using the exponential model (with defined dose-response parameters for Giardia) and survey data on occurrence of Giardia cysts in polluted and pristine waters, levels of water treatment necessary to achieve the acceptable level of risk of infection (1 in 10,000 annually) were determined. Assuming a water utility used those particular source waters, a 3- to 5-log removal/inactivation of cysts would have to occur to meet the USEPA’s recommendation.

The USEPA uses risk of infection rather than illness in its recommendation due to a variety of factors that contribute to probability of illness, such as host susceptibility and variation in virulence of strains of microorganisms. Using infection as the health endpoint of interest is therefore more protective of our immunocompromised populations—infants, the elderly, pregnant women, transplant recipients, among others—which are more likely to develop severe illness from an infection. Health risks may be overestimated for those who ingest less than the assumed amount of water (2 L/person/day) and those with pre-existing immunity to the particular pathogen of interest. Health risks, however, may be underestimated since infections can lead to secondary transmission, which can magnify the impact of exposure to waterborne microorganisms. Risk estimates have been compared to epidemiological data obtained from waterborne outbreaks, and results indicate the probability models can successfully predict health outcomes from exposure to microorganisms.5

Conclusion
The methodology described here can be applied to assess health risks for all types of populations as well as to evaluate microbial water quality for different sources of water (drinking water, recreational water, etc.). More data are needed on the occurrence of microorganisms in water. Plus, the application of sensitive laboratory detection techniques during surveillance studies of viruses and protozoa would lead to better estimates of exposure. Due to the great variability in occurrence, infectivity and pathogenicity of waterborne microorganisms, it’s pertinent that risk assessments are performed for specific microorganisms so the public health impact from microbial-polluted waters can be fully identified.

References

  1. National Academy of Sciences, “Risk assessment in the federal government: managing the process,” National Academy Press, Washington, D.C., 1983.
  2. Haas, C.N., “Estimation of risk due to low doses of microorganisms: a comparison of alternative methodologies,” American Journal of Epidemiology, 118:573-582, 1983.
  3. Regli, S., et al., “Modeling the risk from Giardia and viruses in drinking water,” Journal of American Water Works Association, 83:76-84, 1991.
  4. Haas, C.N., et al., “Risk assessment of virus in drinking water,” Risk Analysis, 13:545-552, 1993.
  5. Haas, C.N., J.B. Rose and C.P. Gerba, Quantitative Microbial Risk Assessment, John Wiley & Sons Inc., New York, 1999.
  6. U.S. Environmental Protection Agency, “National primary drinking water regulations: filtration and disinfection; turbidity; Giardia lamblia, viruses, Legionella, and heterotrophic bacteria,” Federal Register, 54(124):27486-27541, 1989.
  7. Sobsey, M.D., et al., “Using a conceptual framework for assessing risks to health from microbes in drinking water,” Journal of American Water Works Association, 85:44-48, 1993.
  8. Macler, B.A., and S. Regli, “Use of microbial risk assessment in setting United States drinking water standards,” International Journal of Food Microbiology, 18:245-256, 1993.
  9. Gerba, C.P., et al., “Waterborne rotavirus: a risk assessment,” Water Research, 30:2929-2940, 1996.
  10. Rose, J.B., C.N. Haas and S. Regli, “Risk assessment and control of waterborne giardiasis,” American Journal of Public Health, 81:709-713, 1991.
  11. U.S. Environmental Protection Agency, Guidance Manual for Compliance with Filtration and Disinfection Requirements for Public Water Systems Using Surface Water Sources, EPA Report No. 570/9-88-018, USEPA, Washington, D.C., 1991.
  12. Macler, B.A., “Acceptable risk and U.S. microbial drinking water standards,” Safety of Water Disinfection, ed. by G.F. Craun, ILIS Press, Washington, D.C., pp. 619-626, 1993.
  13. Craun, G.F., “Cause of waterborne outbreaks in the United States,” Water Science and Technology, 24:17-20, 1991.
  14. Kramer, M.H., et al., “Surveillance for waterborne disease outbreaks: United States, 1993-1994,” Morbidity Mortality Weekly Report, 45(SS-1):1-15, 1996.

About the author
Dr. Kristina D. Mena is assistant professor of environmental sciences at the University of Texas Health Science Center at Houston School of Public Health. She earned a master of science in public health (MSPH) degree from the University of South Florida and a doctorate in environmental microbiology from the University of Arizona. Her research interests include laboratory detection of waterborne and foodborne pathogens, and application of microbial risk assessment to address related public health issues. She can be contacted at (915) 747-8514, (915) 747-8512 (fax) or email: kmena@utep.edu

Drinking Water Microbiology and Home Defense

Friday, April 19th, 2002

By Dale W. Griffin, MSPH, PhD

Most of us don’t give a second thought to drinking out of our home taps. Whether our source of water is a private well or a local water treatment facility, we assume that it poses little if any risk to our welfare. The reality is that there is risk. Water treatment plants utilize microbial water quality standards, which are set by the U.S. Environmental Protection Agency (USEPA) and are based on acceptable risk levels. In other words, a certain number of illnesses in the population, which are due to microbes being delivered through the distribution line, are acceptable. The current risk goal for drinking water plants is no more than 1 illness per 10,000 individuals served by the system per year. The key word here is “goal” and thus doesn’t reflect true risk. Those who utilize private wells for their water may have their water analyzed by local public health departments; however, most of these systems aren’t checked on a regular basis, if at all, as private wells aren’t regulated by state and federal drinking water standards.

Assessing risks
While there’s risk from drinking water sources, the populations at highest risk are the young, the old or the immunocompromised. Numerous cases are attributed to storm events where treatment facilities are overwhelmed by highly turbid waters containing microbial pathogens or wells contaminated by the transport of pathogens into the aquifer via recharge (movement of rainwater through soil and into the aquifer). Of the 548 waterborne outbreaks between 1948 and 1994, 51 percent followed precipitation events.1 One means of minimizing risk from our water sources is to install an additional barrier. As this industry understands, many point-of-use (POU) water treatment systems are available for home or office; and, if utilized and maintained as designed, are an effective “firewall” to the occasional pathogenic microbial contaminant.

Microbial pathogens of concern
Table 1 lists microorganisms that have been identified as the causative agent in numerous waterborne outbreak investigations. In 40-to-50 percent of the outbreaks that occur each year, the responsible agent is never identified. The organisms that have presented a unique challenge to water treatment facilities are those that are resistant to disinfectants. These disinfectant-resistant organisms typically have one thing in common—they move through the environment from host to host in a cyst or spore stage. The cyst or spore is an egg-like vesicle that protects the organism from physical stresses (desiccation, heat, etc.) that it may encounter outside of its host.

Giardia & Crypto
The protozoa Giardia and Cryptosporidium (see Figure 1) are prime examples of disease-causing agents and are identified in drinking water outbreaks each year (25 percent of outbreaks during 1997-8). When annual outbreak statistics are compiled, Giardia is often identified as causing the most waterborne outbreaks or cases of waterborne illness (see www.cdc.gov/epo/mmwr/preview/mmwrhtml/ss4907a1.htm)2 and this is due in part to its resistance, cyst form, and its prevalence in source waters. Although Giardia infections cause few deaths and, in most cases, are responsible for only a self-limiting gastroenteritis, it’s ironic that this organism is ignored by the research funding agencies given its impact on U.S. public health. Cryptosporidium, on the other hand, has received a lion’s share of research funds over the last several years for good reason, as it caused the largest waterborne outbreak in U.S. history when over 400,000 Milwaukee, Wis. residents were infected through the city’s public utility water distribution lines in 1993. The outbreak followed a storm. While most cases of cryptosporidiosis also are self-limiting—an illness that clears without treatment—symptoms such as gastroenteritis are typically severe and infection can be fatal, particularly to the very young and immuno-compromised.

Due to the resistant nature of Giardia cysts and Cryptosporidium oocysts, filtration is the recommended means of preventing these organisms from making it to the tap. Cryptosporidium oocysts are the smaller of the two and range in size from 4-to-8 microns (µm). Those choosing a POU water treatment system for their customers should keep the oocyst spore size and the recommendation of filtration over disinfection in mind when selecting a unit.

E. coli
Many organisms of concern, such as bacteria and viruses, aren’t spore formers yet still account for a number of drinking water outbreaks each year. E. coli O157:H7, which is mostly associated with foodborne outbreaks, has emerged as a concern for the water industry due to the severity of its illness and the fact that infections can be fatal. The groups at highest risk are the elderly and children under 5 years of age. Approximately 2-to-7 percent of outbreak cases lead to hemolytic uremic syndrome (the breakdown of red blood cells) and, even with intensive care, 3-5 percent of those are usually fatal (see www.cdc.gov/ncidod/dbmd/disease infor/escherichiacoli_g.htm). In 1993, an E. coli O157:H7 outbreak attributed to an unchlorinated drinking water supply in the Burdine Township of Missouri (population 3,132) resulted in 243 illnesses, four of which were fatal.

Another waterborne E. coli outbreak, which more recently received a significant amount of press, occurred in Walkerton, Ontario, Canada in May 2000. This event was attributed to a heavy rain and spread via the town’s municipal water supply. The contamination site was believed to be a supply well whose groundwater was vulnerable to surface contaminants. Over 1,300 cases of illness were documented with seven fatalities. While E. coli O157:H7 was identified as the primary microbial contaminate, Campylobacter spp., also was identified in a number of screened stool specimens and may have contributed to a number of the cases. In addition to E. coli O157:H7 and Campylobacter spp., other bacteria were encountered that are routinely identified in drinking water outbreaks, such as Shigella sonnei and a species of Salmonella.

Incidence occurrence data
Waterborne outbreaks attributed to contaminated groundwater accounted for 88.2 percent of all outbreaks during 1997-1998 (see www.cdc.gov/mmwr/preview/mmwrhtml/ss4904a1.htm).3 This groundwater outbreak data are based on the total number of outbreaks (community and non-community systems) and illustrate the susceptibility of our groundwater to contamination events.  

Systems particularly vulnerable are private ones where the water may not be routinely monitored and isn’t filtered or chlorinated before it reaches the tap. Systems such as these are particularly vulnerable to contamination by pathogenic human viruses in areas where septic tanks are utilized for sewage disposal (see Figure 3). The reason is the size of viruses (typically 10 times smaller than the average bacteria size of 0.75 µm), which allows them to pass through interstitial spaces—the gaps between soil particles—in dense soils that would trap larger pathogens (bacteria and protozoa).

One surveillance of a U.S. groundwater source (samples taken from various sites in different geological settings) found enterovirus genomes in 30 percent of 133 samples, Hepatitis A virus genome in 8.6 percent of 139 samples and Rotavirus genome in 13.8 percent of 130 samples.4 Viruses of concern are enteroviruses (a group consisting of the Polio, Coxsackie and Echoviruses), Hepatitis A viruses, Norwalk and Norwalk-like viruses and Rotaviruses. Most of these viruses produce self-limiting “cold-like” symptoms or diarrhea, but some can produce paralysis, meningitis and cause complication to developing fetuses.

Conclusion
Pathogenic microorganisms have a well-documented track record of contaminating our drinking water sources whether it’s surface or groundwater. Even when we utilize advanced water treatment techniques, pathogens can penetrate these barriers if equipment used in these applications isn’t closely monitored and maintained. As we’ve advanced in our understanding of water treatment, one thing is obvious—the more barriers, the lower the risk. The use of a properly installed, maintained and adequate POU device at home or office is an additional barrier that can protect your customers’ health, their family’s health, or their business personnel from a contamination event.

References

  1. Curriero, F.C., et al., “The Association Between Extreme Precipitation and Waterborne Disease Outbreaks in the United States, 1948–1994,” American Journal of Public Health, 91(8):1194-1199, August 2001.
  2. Furness, B.W., et al., “Giardiasis Surveillance — United States, 1992-1997,” Centers for Disease Control & Prevention, Morbidity & Mortality Weekly Report, 49(SS07);1-13, August 11, 2000.
  3. Barwick, R.S., et al., “Surveillance for Waterborne-Disease Outbreaks — United States, 1997-1998,” Centers for Disease Control & Prevention, MMWR, 49(SS04):1-35, May 26, 2000.
  4. Abbaszadegan, M., et al., “A Strategy for Detection of Viruses in Groundwater by PCR,” Applied & Environmental Microbiology, 65(2):444-449, February 1999.

About the author
Dale W. Griffin, Ph.D., MSPH, is a public health and environmental microbiologist with the U.S. Geological Survey, Center for Coastal Sciences, in St. Petersburg, Fla. He can be reached at (727) 803-8747 x3113, or email: dgriffin@usgs.gov

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