1.1 As the General Accountability Office (GAO) reported in 2018 (2), the discovery of toxic levels of lead in drinking water in Flint, Michigan in 2015 renewed awareness about the risks that lead poses to public health. Exposure to lead can result in elevated blood lead levels and negative health effects. Children are at particular risk, because their growing bodies absorb more lead than adults, so protecting them from lead is important to lifelong good health. According to the Centers for Disease Control and Prevention (CDC), elevated blood lead levels have been linked to anemia, kidney and brain damage, learning disabilities, and decreased growth. As a result of widespread human use, lead is prevalent in the environment; for example, it can be found in paint (lead in paint was banned in the United States in 1978)4 and soil, and can leach into drinking water from lead-containing plumbing materials, such as faucets and drinking fountains.

1.2 Lead in school drinking water is a concern because it is a daily source of water for over 50 million children enrolled in public schools. The pattern of school schedules—including time off over weekends, holidays, and extended breaks—can contribute to standing water in the school’s plumbing system. If there is lead in the plumbing system, the potential for it to leach into water can increase the longer the water remains in contact with the plumbing. Estimating the risk of lead contamination of schools' drinking water at the State level is a complex and important challenge. Variable water quality among water systems and changes in water chemistry during distribution affect lead dissolution rates from pipes and fittings. In addition, the locations of lead-bearing plumbing materials are uncertain. EPA, 2002 (3), Triantafyllidou and Edwards, 2012 (4).

1.3 The US EPA is responsible for enforcement of the Safe Drinking Water Act (SDWA) on Tribal land; there is no delegation of this authority to the States.

1.4 Sections 50105 and 50110 of the Infrastructure Investment and Jobs Act (Public Law 117–58) (1) provides funding and directs the US EPA and the Department of Interior to address lead in drinking water systems that provide potable water to schools and on Tribal land. EPA has announced that in accordance with this statute, the Agency discourages partial lead service line replacements and encourages full replacement of deficient service lines. The legislation provided the US EPA with approximately $15 billion over a 5-year period to achieve this goal.

1.5 This guide describes steps to rapidly identify community and public water systems, as defined in the SDWA, at risk of lead concentrations exceeding the maximum contaminant level (MCL), using publicly available data. These steps augment and complement the records review activities that the US EPA encourages as part of the LSLR program.

1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.