Experimental studies documenting potential impacts of galvanic corrosion on
lead release after partial lead service line replacements are limited. In order to provide
more insights, long-term experiments of simulated partial lead service line replacements
were conducted, with emphasis on rigorously testing the longevity of galvanic
corrosion with respect to lead contamination, and on assessing the relative effects of
chloride and sulfate by measuring lead release into drinking water at two different
Chloride to Sulfate Mass Ratios (CSMRs). The experimental apparatus was constructed to track lead
leaching from simulated partial lead service line replacements. The test rigs consisted
of a copper pipe section that was electrically connected to lead pipe, with a total rig
length of three feet. Three distinct phases of experimentation were undertaken:
all rigs were initially exposed to synthetic tap water with a low chloride to sulfate
mass ratio (CSMR) of 0.2 ("low CSMR water");
the test water was then switched to an aggressive synthetic tap water with a high
CSMR of 16.2 ("high CSMR water"), and all other water parameters were kept the same
as 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 to
removal of the connecting strap wires.
Throughout the experiment (i.e. in all three phases), water was completely changed
inside the pipes three times per week, using a "dump and fill" protocol. The contribution
of 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.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 760 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 5 |
| Published : | 11/01/2009 |
