【国外标准】 Standard Guide for Using Publicly Available Data to Identify Schools and Vulnerable Communities at High Risk for Elevated Lead in Drinking Water

4.1 Lead can enter drinking water when service lines or plumbing fixtures that contain lead corrode, especially where the water has high acidity or low mineral content. According to the EPA, lead typically enters school drinking water as a result of interaction with lead-containing plumbing materials and fixtures within the building (EPA 2019 EPA 2018, (5)). Although lead pipes and lead solder were not commonly used after 1986, water fountains and other fixtures were allowed to have up to 8 percent lead until 2014 (GAO, 2018 (2)). Consequently, both older and newer school buildings can have lead in drinking water at concentrations that exceed the NPDWR.4.2 Following the reports in 2015 of elevated lead levels in the water in Flint, Michigan, Congress passed the Water Infrastructure Improvements for the Nation Act in 2016 (Public Law 114-322), which, among other things, amended the SDWA, to establish a grant program for states to assist school districts in voluntary testing for lead contamination in drinking water at schools. As a condition of receiving funds, school districts are required to test for lead using standards that are at least as stringent as those in federal guidance for schools.4.3 California’s State Water Resources Control Board’s Division of Drinking Water initiated an aggressive program of sampling and public water systems supplying water to schools in 2018. California Assembly Bill 746 published on October 12, 2017, effective January 1, 2018, requires community water systems to test lead levels, by July 1, 2019, in drinking water at all California public, K-12 school sites that were constructed before January 1, 2010.4.4 Lobo (2021) (6) reports that two factors predominantly control lead leaching into the drinking water: (1) the presence or absence of lead-bearing plumbing materials, and (2) water quality that promotes the formation of soluble or insoluble lead corrosion products. This guide provides a method of using publicly-available information to determine if the water supplied to schools presents an unacceptable lead exposure hazard.4.5 The procedures described in the guide are consistent with Sections 4, 5, and 6 of Guide E3032.1.1 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.