Description
Utility experience under the Lead and Copper Rule was examined to provide improved insight into corrosion control. Average 90th percentile lead concentrations were highest in very low alkalinity water (<30 mg/L as CaCO3) at utilities that did not use inhibitors; lead release was significantly reduced at higher alkalinities. Average lead releases were 20-90 percent lower for utilities using phosphate inhibitors (orthophosphates, polyphosphates, and blended phosphates) in very low alkalinity waters than for utilities not using inhibitors. At alkalinities of 30-74 mg/L as CaCO3 and at pH values > 7.40, it appeared that polyphosphate inhibitors had adverse effects on average lead release. Utilities with pH < 7.40 and high alkalinity waters had the highest copper concentrations. Phosphate inhibitors were usually beneficial in mitigating copper release; however, most benefits were at utilities with pH < 7.80 and alkalinity > 90 mg/L as CaCO3. Inhibitors appeared to adversely affect average copper release in some pH and alkalinity categories. Includes 23 references, tables, figures.
Product Details
- Edition:
- Vol. 87 – No. 7
- Published:
- 07/01/1995
- Number of Pages:
- 12
- File Size:
- 1 file , 890 KB
- Note:
- This product is unavailable in Ukraine, Russia, Belarus
