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Six residential water meters were used in side-by-side testing to identify their potentiallead (Pb) and copper (Cu) contributions to water in first-draw stagnation samples. The metersranged in service age from new, never used units to one that had been in service for 40continuous years. Five of the meters were brass with up to 8% Pb content, and one was the new"no-lead" brass in which the Pb content is less than 0.2%, and bismuth (Bi) and selenium (Se) (aregulated element) are used in its place. Corrosion rates varied little between meters that hadbetween 4 and 26 years of use, but the new leaded-brass meters continued to release Pb atconcentrations above 15 g/L, the 90th percentile action level (AL), in a 250 mL sample evenafter 138 days of intermittent water flow. The new no-lead meter released approximately 1 g/LPb and Se, substantially less than leaded-brass meters, without other water quality impacts.Finally, the 40-year-old brass meter had been dropped prior to installation in the test rig.Subsequent testing found that the meter released up to 330 g/L Pb and 4.0 mg/L Cu. Theseelevated results were probably due to the physical jarring causing internal corrosion scales todislodge from the meter. After 57 days of exposure, both Pb and Cu were reduced to below theirrespective ALs, although elevated particulate metal concentrations were still detected afterwards. Includes references, tables, figures.

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Edition: Vol. - No. Published: 06/01/2006 Number of Pages: 20File Size: 1 file , 400 KB