To establish a moratorium on the promulgation and implementation of certain drinking water regulations promulgated under the Safe Drinking Water Act, to modify the definition of public water system, and for other purposes.

Prohibits the Administrator of the Environmental Protection Agency from implementing any national primary drinking water regulation under the Safe Drinking Water Act (the Act) or any similar regulation until this Act's requirements are met and legislation that extends the authorization of the Act is enacted. Requires the Administrator to study and report to the Congress on: (1) each final regulation promulgated under the Act and regulatory alternatives that reflect a range of levels of safety or direct health benefits; (2) any health effect an alternative would prevent and the system-level incremental cost of each alternative; (3) the contaminants listed pursuant to the Act for purposes of considering revisions to the list, taking into account anticipated adverse health effects of the contaminant, the risk or safety factors associated with the maximum contaminant level, and whether the contaminant may occur in public water systems; (4) compliance deadlines; (5) whether a regulation should apply exclusively to small public water systems; and (6) recommended alternatives to ensure that States and political subdivisions meet funding needs to carry out the Act. Directs the Administrator, if the implementation or promulgation of a primary drinking water regulation is justifiable to protect human health, to implement or promulgate such regulation without regard to the requirements of this Act. Amends the Safe Drinking Water Act to exclude from the definition of "public water system" any system which: (1) relies only on surface water supplies; (2) serves only seasonal rental residences; and (3) serves 100 or fewer individuals.