Preamble to the final rule of Lead and Copper
Excerpt from 58 FR 26479, June 7, 1991
a. Action Level for Lead in School Drinking Water. In January 1989, EPA published a manual, "Lead in School's Drinking Water" [updated in 1994] to assist school officials in identifying whether a school had a problem with lead in drinking water, the steps to reduce or eliminate this problem, and information on training personnel in sampling and remedial programs. As a part of this program, EPA recommended that schools collect 250 ml first-draw samples from water fountains and outlets and that the water fountains and/or outlets be taken out of service if the lead level exceeded 0.020 mg/L. The sample was designed to pinpoint specific fountains and outlets that required remediation (e.g. water cooler replacement).
As discussed above, the final rule establishes a lead action level of 0.015 mg/L at the 90th percentile. The action level in the final rule is based on 1 liter first-draw samples collected from numerous targeted sampling sites throughout a distribution system and is designed to identify system-wide problems and not problems in single outlets. This is quite different from the sampling conducted in schools where EPA is concerned with locating individual outlets that require remediation. The school sampling protocol maximizes the likelihood that the highest concentrations of lead are found because the first 250 ml are analyzed for lead after overnight stagnation (usually much longer that the 6 hour minimum specified for this regulation).
Consequently, the two lead action levels differ because of the different problems they seek to detect and the different monitoring protocols used in the two situations.
EPA continues to recommend that schoolstake action at individual outlets with lead levels greater than 0.020 mg/L. EPA will make an effort to ensure that schools, laboratories, states, and consumers understand the distinction between the action level under the rule and the that applicable to public schools.