The 2007 National Academy of Engineering Grainger Challenge Prize competition sought innovative solutions for removing arsenic from drinking water that is slowly poisoning tens of millions of people in developing countries.

The winning systems had to be affordable with low life-cycle cost, robust, reliable, easy to maintain, socially acceptable and environmentally friendly. As sustainable technologies, they also had to be within the manufacturing capabilities of the countries where they would be deployed and could not degrade other water-quality characteristics or introduce pathogens. The prize winners are recognized for the development, in-field verification, and dissemination of effective techniques for reducing arsenic levels in water. All of the winning systems meet or exceed the local government guidelines for arsenic removal and require no electricity.

The National Academy of Engineering, with the generous support of The Grainger Foundation, will award gold, silver, and bronze Grainger Challenge Prizes of $1,000,000, $200,000, and $100,000, respectively, to the winning systems.

A significant aspect of reviewing the finalists for the Grainger Challenge Prize was physical testing of the candidate systems. NAE and The Grainger Foundation wish to express deep appreciation to the U.S. Environmental Protection Agency's Office of Research and Development for hosting the testing at its National Risk Management Research Laboratory in Cincinnati, as well as to the facility's contractor, Shaw Environmental & Infrastructure Inc., for conducting the tests under contract with the NAE.

GOLD AWARD WINNER

Abul Hussam, an associate professor in the department of chemistry and biochemistry at George Mason University, Fairfax, Va., receives the Grainger Challenge Gold Award of $1 million for his SONO filter, a household water treatment system. Hussam was born in Kushtia, Bangladesh. He graduated in Chemistry (B.S. Honors and M.S.) from the University of Dhaka and earned his Ph.D. in Analytical Chemistry from the University of Pittsburgh in Pennsylvania. He has published and presented more than 90 scientific papers in international journals, proceedings, and books. In collaboration with others, Hussam has established an environmental research laboratory in Kushtia and is actively engaged in educating the public on the nature of present and future environmental crises.

The Gold Award-winning SONO filter is a point-of-use method for removing arsenic from drinking water. A top bucket is filled with locally available coarse river sand and a composite iron matrix (CIM). The sand filters coarse particles and imparts mechanical stability, while the CIM removes inorganic arsenic. The water then flows into a second bucket where it again filters through coarse river sand, then wood charcoal to remove organics, and finally through fine river sand and wet brick chips to remove fine particles and stabilize water flow. The SONO filter is now manufactured and used in Bangladesh.

SILVER AWARD WINNER

Arup K. SenGupta, John E. Greenleaf, Lee M. Blaney, Owen E. Boyd, Arun K. Deb, and the nonprofit organization Water For People share the Grainger Challenge Silver Award of $200,000 for their community water treatment system. SenGupta is P.C. Rossin Senior Professor and a professor of chemical engineering and of civil and environmental engineering at Lehigh University in Bethlehem, Pa. Boyd is chief executive officer of SolmeteX Co. in Northborough, Mass. Deb is a retired vice president of Roy F. Weston Inc. (now Weston Solutions Inc.) in West Chester, Pa. Greenleaf is a Ph.D. candidate in civil and environmental engineering, and Blaney recently earned a bachelor's degree in environmental engineering; they performed laboratory research under SenGupta at Lehigh University.

The system developed by the Silver Award-winning team is applied at a community's well head. Each arsenic removal unit serves about 300 households. Water is hand-pumped into a fixed-bed column, where it passes through activated alumina or hybrid anion exchanger (HAIX) to remove the arsenic. After passing through a chamber of graded gravel to remove particulates, the water is ready to drink. This system has been used in 160 locations in West Bengal, India. The water treatment units, including the activated alumina sorbent, are being manufactured in India, and villagers are responsible for their upkeep and day-to-day operation. The active media are regenerated for re-use, and arsenic-laden sludge is contained in an environmentally safe manner with minimum leaching.

BRONZE AWARD WINNER

The Children's Safe Drinking Water Program at Procter & Gamble Co. (P&G), Cincinnati, receives the Grainger Challenge Bronze Award of $100,000 for the PUR™ Purifier of Water coagulation and flocculation water treatment system. The program consists of emergency relief work and establishing not-for-profit markets to provide P&G’s safe drinking-water technology to children and their families in the developing world. Greg Allgood, director of the Children's Safe Drinking Water Program, is accepting the prize for P&G.

The PUR™ technology combines chemicals for disinfection, coagulation, and flocculation in a sachet that can treat small batches of water in the home. It is simple, portable, and treats water from any source. First, the sachet contents are stirred into a 10 liter bucket of water for five minutes. As the water rests for another five minutes, arsenic and other contaminants separate out. The water is then poured through a clean cloth to filter out the contaminants. After another 20 minutes to complete the disinfection process, the water is safe to drink. As part of P&G's focal philanthropy program, the Children's Safe Water Drinking Program has worked with partners to provide 57 million sachets in more than 30 countries over the past three years, enough to purify more than 570 million liters of safe drinking water. In Bangladesh each sachet is about the cost of an egg.