Effect of Phosphates Used for Corrosion Control at Drinking Water Treatment Plants - on POTW Effluent and Sludge

Alvin J. Salkind, Qizhong Guo, Charles Grun, and Ronald Lockwood
Final Report, NJDEP Division of Science and Research, 1996


Abstract

 A literature search of health effects of lead, lead solubility in water, inhibitors to lead solubility, and effect of zinc in waste water sludges when disposed in land applications has been conducted.

The quantity of corrosion control chemicals (Zinc and PO4) added to the NJ State Drinking Water Supply to meet the Lead Copper Rule (LCR) has been calculated at 83 Kg of Zinc and 288 Kg of PO4 per day, for the present list of installations permitted to add these chemicals to meet the LCR. This number should be recalculated and monitored as more installations are allowed to use these chemicals.

This quantity is 23.4% of Zinc and 5.2% of PO4 entering the corresponding POTWs.

The average Zinc content of sludge from POTWs with LCR corrosion control chemical input is 1,193 mg Zn/Kg sludge, which is 43% of 2,800 mg Zn/Kg limit for land application