Office of Drinking Water Quality

Public Water Programs

Control of Lead & Copper for Small and Medium-Size Community Systems and Non-Transient Not-Community Systems

Lead & Copper Action Levels

• The lead action level is exceeded if the concentration of lead is greater than 0.015 mg/L in the 90th percentile.
• The copper action level is exceeded if the concentration of lead is greater than 1.3 mg/L in the 90th percentile.
• The 90th percentile is determined as follows:

• For a system with 20 samples, the 90th percentile is the 18th highest concentration sample.
• For a system with 10 samples, the 90th percentile is the 9th highest concentration sample.
• For a system with 5 samples, the 90th percentile is the average of the two highest concentration samples.

Initial Sampling

• Monitoring occurs during each six-month monitoring period until:

• The system exceeds lead and copper action levels and is therefore required to implement corrosion control treatment requirements (see corrosion control), or
• The system meets the lead and copper action levels during two consecutive six-month monitoring periods in which case the system may reduce the frequency of monitoring to once per year. If the system meets lead and copper action levels for three consecutive years, the system may reduce the frequency of monitoring from annually to once every three years.

• The number of samples is based upon the following table:

Corrosion Control

• Any small or medium-size water system that is required to complete the corrosion control steps may cease completing the treatment steps whenever the system meets both action levels during each of two consecutive monitoring periods.
• If a system thereafter exceeds the lead or copper action level, completion of the treatment steps, beginning with the first treatment step not completed, is required.
• For more information see Applicability of Corrosion Control Treatment Steps to Small, Medium-size and Large Water Systems

Public Education

• In the case that there are violations in the action levels of either lead or copper, it is required that the system informs the public of any violations, the health effects of lead or copper, and steps you can take in the home to reduce exposure to lead in drinking water.
• For more information see Public Education and Supplemental Monitoring Requirements or
• EPA's Lead in Drinking Water Regulation: Public Education Guidance

Tap Sample Collection Instructions:

• Directions for Homeowners
• Directions for Facilities

Other Information

• Fact Sheet for Public Water Systems that Serve 3300 or Fewer Persons
• Lead and Copper Rule: A Quick Reference Guide
• Ground Water and Drinking Water: Lead and Copper
• Lead in Drinking Water