The EPA Administrator signed a final action on perchlorate on June 19, 2020 (85 FR 43990). Considering the best available science and the proactive steps that EPA, states and public water systems have taken to reduce perchlorate levels, the Agency determined that perchlorate does not meet the criteria for regulation as a drinking water contaminant under the Safe Drinking Water Act. Therefore, the agency withdrew the 2011 regulatory determination and made a final determination to not issue a national regulation for perchlorate at this time. EPA performed a new health impact analysis based on recommendations from the Science Advisory Board. The new analysis shows that the concentrations at which perchlorate may present a public health concern are higher than the concentrations considered in the 2011 regulatory determination. The updated occurrence information and the new health impact analysis are the best available information. Based on this updated data and analysis, EPA made a final determination that perchlorate is not found in drinking water with a frequency and at levels of public health concern to support a meaningful opportunity for health risk reduction through a national perchlorate drinking water regulation.