AWWA WQTC71626

Experimental studies documenting potential impacts of galvanic corrosion onlead release after partial lead service line replacements are limited. In order to providemore insights, long-term experiments of simulated partial lead service line replacementswere conducted, with emphasis on rigorously testing the longevity of galvaniccorrosion with respect to lead contamination, and on assessing the relative effects ofchloride and sulfate by measuring lead release into drinking water at two differentChloride to Sulfate Mass Ratios (CSMRs). The experimental apparatus was constructed to track leadleaching from simulated partial lead service line replacements. The test rigs consistedof a copper pipe section that was electrically connected to lead pipe, with a total riglength of three feet. Three distinct phases of experimentation were undertaken:all rigs were initially exposed to synthetic tap water with a low chloride to sulfatemass ratio (CSMR) of 0.2 ("low CSMR water");the test water was then switched to an aggressive synthetic tap water with a highCSMR of 16.2 ("high CSMR water"), and all other water parameters were kept the sameas in the "low CSMR water" of Phase 1; and finally, the rigs continued to be exposed to the "high CSMR water" as in Phase 2,but without direct galvanic corrosion between the lead and copper pipe due toremoval of the connecting strap wires.Throughout the experiment (i.e. in all three phases), water was completely changedinside the pipes three times per week, using a "dump and fill" protocol. The contributionof galvanic connection (or lack thereof) to lead release was assessed by measuring total lead concentration in water and galvanic current magnitude. Includes 3 references, tables, figures, extended abstract only.

Product Details

Edition:

Vol. - No.

Published:

11/01/2009

Number of Pages:

5

File Size:

1 file , 760 KB