Brothers Michael (left) and Timothy Martens inspect copper machine parts on the factory floor of M&H Engineering. The company has hired back some workers who were laid off during the recession.
Water fountains in Washington, D.C., were sealed for lead testing in 2004 after tap water was found to contain as much as 30 times the acceptable levels. Earlier, the utility switched from disinfecting water with chlorine to chloramine, but it caused lead in the pipes to leach out into the water supply.
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