In the Lead and Copper Rule, if a water system exceeds the 90th percentile for the lead action level, the system must also _______.

• A. Educate the affected public
• B. Provide point-of-use devices to the customers in the affected area
• C. Install or increase an existing process to raise the alkalinity in the finished water
• D. Provide bottled water to the affected public until the problem is solved

Answer: (A)

When the lead action level is exceeded at the 90th percentile, informing and educating the public becomes the mandated response. The Lead and Copper Rule uses the 90th percentile to gauge lead exposure risk; if that level is above the action level, the system must communicate with customers about the results, health risks, and steps they can take to reduce exposure. This public education helps ensure people know how to minimize lead intake (such as using cold water for consumption, flushing taps, and following any system-specific guidance) while the system works on longer-term fixes like corrosion control and lead service line replacements. The other options aren’t universal requirements of the rule in this context: providing point-of-use devices, strictly increasing finished-water alkalinity, or supplying bottled water aren’t the mandatory follow-up actions tied to this exceedance, though they may be considered or recommended in certain situations.