| Autor: |
Boyd, Glen R.1 gboyd@tulane.edu, Shetty, Prasad2, Sandvig, Anne M.3, Pierson, Gregory L.4 |
| Předmět: |
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| Zdroj: |
Journal of Environmental Engineering. Oct2004, Vol. 130 Issue 10, p1188-1197. 10p. |
| Abstrakt: |
The concentrations of total, colloidal, and truly dissolved lead (Pb) were investigated in tap water following laboratory simulations of partial lead pipe replacements. Old lead pipes were recovered from service in New Orleans, La and mounted horizontally in an experimental apparatus at Tulane Univ. Municipal water was diverted for two weeks at low flowrates of 0.2 or 1.1 L/min (0.05 or 0.3 gal/min) through two pipe trains operated continuously and two pipe trains operated intermittently. Samples were collected to determine relative concentrations and time needed for each form of Pb (total, colloidal, and truly dissolved) to stabilize below the U.S. Environmental Protection Agency action level (AL) of 15 μg/LPb. Results demonstrate that total Pb concentrations exceeded the AL immediately following simulated partial pipe replacements. In most cases, total Pb concentrations were reduced below the AL by flushing for 15–30 min but subsequent sampling revealed total Pb concentrations greater than the AL. Continuous flow pattern flushing was more effective at stabilizing total Pb concentrations below the AL than intermittent flows. Results also demonstrate that colloidal Pb concentrations were 38–54% of total Pb and truly dissolved Pb concentrations were 41–60% of total Pb concentrations after stabilization. [ABSTRACT FROM AUTHOR] |
| Databáze: |
GreenFILE |
| Externí odkaz: |
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