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----------------------------------Leading the lead-free push
Rich Giani, water quality manager, Washington, D.C. Water and Sewer Authority (DC WASA)
Sometimes a “fix” creates more problems. Responding to a federal mandate, in 2001 DC WASA switched from a free-chlorine disinfectant to adding chloramines to purify its drinking water. The modification caused a jump in lead levels—which, in turn, caused a jump in head-scratching among water managers.
“Available research could not identify a cause or solution,” says Giani. “Literature indicated that lead levels should have been decreasing or, at a minimum, remaining stable under water-quality conditions provided to the distribution system.”
Springing into action, Giani formed a research team that included U.S. Environmental Protection Agency representatives, University of Washington experts, and consultants from Omaha, Neb.-based HDR Inc. and Millburn, N.J.-based Hatch Mott Mac-Donald. The crew engineered the concept of “lead profiling”: collecting sequential samples from a home tap to the main after a six-hour stagnation period, then testing the samples to measure dissolved-lead and particulate concentration. Applying this research, DC WASA brought lead concentrations back down below EPA action levels and calmed panicked citizens.
Thanks to Giani, drinking-water leaders across the country can now better understand how changing treatment chemicals can impact corrosion rates and the release of metals into drinking water supplies. Giani, in turn, learned from the process.
“Managing DC WASA's technical team and providing support on the research level, although extremely trying at times, was priceless,” he says. “To be part of a group of experts attempting to solve a complex problem during a public crisis provides you with respect for drinking water programs.”
— Jenni Spinner