In response to the Flint, Michigan water crisis, EPA published a final rule on January 15, 2021 addressing testing, pipe replacement and related issues. The rule mandates additional requirements for sampling tap water, corrosion control, public outreach and testing water in schools. The rule continues the requirement for replacement of lead service lines (LSLs) when the action level is exceeded, but requires that a utility replace at least 3 percent of its lines annually, compared to 7 percent under the prior regulation. The EPA takes the position that although 3% is less than 7%, the new replacement program has fewer loopholes. Under the prior version, water systems were able to "test out" of the LSL replacement program, delay implementation because they did not have LSL inventories, or complete partial replacements and therefore, few water systems ever satisfied the full 7%. Several citizen and environmental groups immediately filed lawsuits challenging the rule. On March 12, 2021 EPA delayed the effective date of the rule to June 17, 2021.