LEAD AND COPPER CORROSION CONTROL

EPA sponsored a three year project in which researchers at the Univers ity of South Carolina performed comprehensive treatment and distributi on system monitoring studies for several communities in South Carolina , The primary objective was to provide insight to state regulators and water suppliers on appropriate corrosion control strategies. This pap er presents: (1) a comparison of the use of a batch-mode (fill-and-dra w) system to a continuous flow pilot system in performing corrosion tr eatability studies, (2) an evaluation of a method for measuring corros ion rates in copper plumbing systems by gravimetric weight-loss, and ( 3) an evaluation of the treatment effectiveness of several chemical tr eatment alternatives. Two months were requires to establish relatively stable operation in the continuous-flow pilot system, after which ano ther two to three months were necessary to obtain reliable data from e valuation of treatment method efficiency. At lease one month was requi red to stabilize the operation in the batch-mode system. The pilot stu dies indicated that the most effective treatment alternatives for the dilute acidic ground water included pH adjustment to approximately 7.5 and orthophosphate addition to a 3 mg/L concentration. However, field studies conducted during the period of this research study indicated that municipal treatment systems could sufficiently meet the national primary drinking water for lead and copper by pH and alkalinity adjust ment only.