What is the main objective of the Lead and Copper Rule?

• A. Control corrosiveness of the finished water
• B. Apply cathodic protection throughout the distribution system
• C. Make facilities increase source water treatment for preventative measure
• D. Apply enhanced coagulation if out of compliance

Answer: (A)

The main idea behind the Lead and Copper Rule is to protect people by reducing how much lead and copper can leach from pipes and plumbing into the drinking water. That happens by controlling how corrosive the finished water is. Utilities adjust water chemistry—such as pH, alkalinity, and corrosion inhibitors like orthophosphate—to form protective scales on the inside of pipes and minimize release of lead and copper. Regular monitoring at the tap detects whether levels are being kept in check, and corrosion control measures are implemented if they’re not.

The other options miss the focus. Cathodic protection targets external corrosion of metal pipes in the distribution system, not the chemical conditions of the water that drive lead and copper release. Increasing source water treatment shifts focus to treating contaminants before it reaches customers, rather than controlling corrosivity in the distribution system. Enhanced coagulation is a treatment strategy aimed at removing other constituents, not specifically about reducing lead and copper leaching at taps.